[en] Landscape Ecological Survey of the Bipindi-Akom II ... - ITTO
[en] Landscape Ecological Survey of the Bipindi-Akom II ... - ITTO
[en] Landscape Ecological Survey of the Bipindi-Akom II ... - ITTO
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<strong>Landscape</strong> ecological survey (1: 100,000) <strong>of</strong> <strong>the</strong> <strong>Bipindi</strong> - <strong>Akom</strong> <strong>II</strong> - Lolodorf region,<br />
Southwest Cameroon
LANDSCAPE ECOLOGICAL SURVEY (1:100,000) OF THE BIPINDI -<br />
AKOM 11 - LOLODORF REGION, SOUTHWEST CAMEROON<br />
B.S. B. S. van Gemerd<strong>en</strong><br />
G.W. Hazeu Hazeu<br />
Trop<strong>en</strong>bos-Cameroon Docum<strong>en</strong>ts 1<br />
The Trop<strong>en</strong>bos-Cameroon Programme, Kribi (Cameroon)<br />
DLO Winand Staring C<strong>en</strong>tre, Wag<strong>en</strong>ing<strong>en</strong> (The Ne<strong>the</strong>rlands)<br />
1999
ABSTRACT<br />
Gemerd<strong>en</strong>, van, B.S, G.W. Hazeu, 1999. <strong>Landscape</strong> <strong>Ecological</strong> <strong>Survey</strong> (1:100,000) o/<strong>the</strong> <strong>Bipindi</strong>-<strong>Akom</strong> lI-Lolodorf<br />
region, Southwest Cameroon. Wag<strong>en</strong>ing<strong>en</strong> (The Ne<strong>the</strong>rlands), Trop<strong>en</strong>bos-Cameroon Docum<strong>en</strong>ts 1,212 pp.; 13 Figs;<br />
14 Tables; 81 Refs; 6 Annexes.<br />
In Southwest Cameroon a reconnaissance reconnaissance scale survey <strong>of</strong> landforms, soils and vegetation was was carried carried out. The survey survey<br />
area covered some 167,000 ha. The altitudinal range was was 40 to 1,000 m.a.s.1. Landforms discerned are: mountains,<br />
complexes <strong>of</strong> hills, isolated hills, hilly and rolling uplands, dissected erosional plains, and floodplains. Four soil types<br />
were described, ranging from well drained drained very very clayey soils (in <strong>the</strong> mountain area) to to very poorly to poorly drained drained<br />
soils (on (on valley bottoms). The The sev<strong>en</strong> sev<strong>en</strong> main main vegetation types include include four types <strong>of</strong> primary to old secondary rain forest<br />
(bound to differ<strong>en</strong>t altitudinal zones), young secondary forest, swamp forest, and secondary shrubland. The patterns<br />
<strong>of</strong> landforms, soil types, and vegetation types are integrated into one 'landscape ecological' map (scale 1: 100,000). The<br />
leg<strong>en</strong>d has a hierarchical structure. It is based primarily on a subdivision in four altitudinal zones, secondly on<br />
landform, and finally on <strong>the</strong> degree <strong>of</strong> disturbance <strong>of</strong> <strong>the</strong> natural vegetation by shifting cultivation.<br />
Keywords: Africa, reconnaissance survey, rain forest, landforms, tropical soils, vegetation, altitudinal zonation.<br />
(1)1999 DLO Winand Staring C<strong>en</strong>tre for Integrated Land, Soil and Water Research (SC-DLO) and <strong>the</strong> Trop<strong>en</strong>bos<br />
Foundation<br />
ISSN: 1566-2152<br />
No part <strong>of</strong> this publication may be reproduced or published in any form or by any means, or stored in a data base or<br />
retrieval system, without <strong>the</strong> writt<strong>en</strong> permission <strong>of</strong> <strong>the</strong> DLO Winand Staring C<strong>en</strong>tre or <strong>the</strong> Trop<strong>en</strong>bos Foundation.<br />
The Trop<strong>en</strong>bos Foundation and SC-DLO assume no liability for any loss resulting from <strong>the</strong> use <strong>of</strong> this report.
CONTENTS<br />
page<br />
PREFACE .................................................... 9<br />
SUMMARy .................................................. 11<br />
1. INTRODUCTION ............................................ 13<br />
1.1 Forest Land Inv<strong>en</strong>tory and Land Evaluation Project (Lul) ............... 13<br />
1.2 Research objectives ........................................ 13<br />
1. 3 Course <strong>of</strong> <strong>the</strong> study ........................................ 13<br />
1.4 Report outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 14<br />
2. STUDY AREA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 15<br />
2.1 Location and infrastructure ................................... 15<br />
2.2 Climate ................................................ 15<br />
2.3 Hydrology ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 17<br />
2.4 Geology................................................ 18<br />
2.5 Geomorphology ........................................... 20<br />
2.6 Soils ....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 20<br />
2.7 Vegetation .............................................. 21<br />
2.8 Wildlife ................................................ 23<br />
2.9 Population .............................................. 23<br />
2.10 2.10 Land-use Land-use ............................................... 24<br />
3. METHODOLOGY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 27<br />
3.1 <strong>Landscape</strong> ecological approach . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 27<br />
3.2 Aerial photo interpretation .................................... 27<br />
3.3 Fieldwork............................................... 28<br />
3.3.1 G<strong>en</strong>eral ............................................ 28<br />
3.3.2 Landform and soil ..................................... 29<br />
3.3.3 Vegetation .......................................... 30<br />
3.4 Classification ...............................,............. .. ............................. ,............. 32<br />
3.5 Leg<strong>en</strong>d and map compilation .................................. 33<br />
4. LANDFORMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 35<br />
4.1 Literature review .......................................... 35<br />
4.2 Landform classification 35<br />
4.2.1 Dissected erosional plains (pd) ............................. 36<br />
4.2.2 Uplands (ul and u2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 36<br />
4.2.3 Hills (hI and h2) ...................................... 37<br />
4.2.4 Mountains (m) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 37<br />
4.2.5 Valley Bottoms (v) ..................................... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 38<br />
5. SOILS .................................................... 39<br />
5.1 Literature review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . 39<br />
5.2 Soil types and classification ., ................................. 40<br />
5.2.1 Nyangong soils ....................................... 41<br />
5.2.2 Ebom soils .......................................... 41<br />
5.2.3 Ebimimbang soils .................... -.................. 42<br />
5
5.2.4 Valley Bottom soils .................................... 42<br />
5.2.5 Soil classification ...................................... 43<br />
5.3 Soil physical characteristics ................................... 45<br />
5.3.1 Texture ............................................ 45<br />
5.3.2 Bulk d<strong>en</strong>sity ......................................... 46<br />
5.3.3 Water ret<strong>en</strong>tion ....................................... 47<br />
5.4 Soil chemical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47<br />
5.4.1 pH and exchangeable acidity .............................. 47<br />
5.4.2 Organic carbon and total nitrog<strong>en</strong> ........................... 48<br />
5.4.3 Available and total phosphorous ............................ 50<br />
5.4.4 Cation exchange capacity and exchangeable bases ................. 50<br />
5.4.5 Clay Clay mineralogy ...................................... 51<br />
5.4.6 Nutri<strong>en</strong>t cont<strong>en</strong>ts cont<strong>en</strong>ts ...................................... 52<br />
5.4.7 Conclusions ......................................... 53<br />
5.5 Soil-Iandform relationships and soil g<strong>en</strong>esis ......................... 53<br />
5.5.1 Soil and landform landform relations ............................... 53<br />
5.5.2 Soil g<strong>en</strong>esis .......................................... 55<br />
6. VEGETATION .............................................. 57<br />
6.1 6.1 Literature Literature review review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 57<br />
6.2 Botanical diversity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 59<br />
6.3 Vegetation classification ..................................... 59<br />
6.4 Plant Plant communities ......................................... 62<br />
6.4.1 6.4.1 Maran<strong>the</strong>s - Anisophyllea community (I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 62<br />
6.4.2 Podococcus - Polyalthia Polyalthia community community (<strong>II</strong>a) ...................... 64<br />
6.4.3 Strombosia - Polyalthia community (lib) ....................... 64<br />
6.4.4 Diospyros - Polyalthia community (<strong>II</strong>c) ........................ 65 65<br />
6.4.5 6.4.5 Carapa - Mitragyna community (Ill) ......................... 66<br />
6.4.6 Xylopia - Musanga community (IV) . . . . . . . . . . . . . . . . . . . . . . . . .. 67<br />
6.4.7 Macaranga - Chromola<strong>en</strong>a community (V) ..................... 67<br />
7. LANDSCAPE ECOLOGICAL MAP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 69<br />
7.1 Leg<strong>en</strong>d Leg<strong>en</strong>d ................................................ 69<br />
7.2 Land use ............................................... 69<br />
7.3 Land mapping units ........................................ 70<br />
7.3.1 Am: mountains above 700 m asl, well drained soils ............... 70<br />
7.3.2 Ahl: isolated hills above 700 m asl, well drained soils .............. 71<br />
7.3.3 Bh2: complex <strong>of</strong> hills betwe<strong>en</strong> 500 and and 700 m asl, well drain soils ...... 71<br />
7.3.4 Bh 1: isolated hills betwe<strong>en</strong> 500 and 700 m asl, well drained soils . . . . . .. 71<br />
7.3.5 Bu2: hilly uplands betwe<strong>en</strong> 500 and 700 m asl; well drained soils ...... 71<br />
7.3.6 Bul: rolling uplands betwe<strong>en</strong> betwe<strong>en</strong> 500 and 700 m m asl; well drained soils ..... 71<br />
7.3.7 ChI: isolated hills betwe<strong>en</strong> 350 and 500 m asl, well drained soils ...... 72<br />
7.3.8 Cu2: hilly uplands betwe<strong>en</strong> 350 and 500 m asl; well drained soils ...... 72<br />
7.3.9 7.3.9 CuI: rolling uplands uplands betwe<strong>en</strong> 350 and 500 m asl; well drained soils soils ..... 72<br />
7.3.10 7.3.10 Dhl: isolated hills below 350 m asl, moderately well drained soils . . . .. 73<br />
7.3. 11 Du2: hilly uplands below below 350 m asl; moderately well well drained soils soils . . . .. 73<br />
7.3.12 DuI: rolling uplands below 350 m asl; moderately well drained soils ... 73<br />
7.3.13 Dpd: dissected erosional plains below 350 m asl; moderately well well drained drained<br />
soils .............................................. 74<br />
7.3.14 Ev: Ev: valley valley bottom; poorly to very poorly drained soils ............. 74<br />
6
REFERENCES . ............................................... 75<br />
ANNEXES . .................................................. 79<br />
I <strong>Landscape</strong> ecological map <strong>of</strong> <strong>the</strong> <strong>Bipindi</strong> - <strong>Akom</strong> rr -Lolodorf region, southwest<br />
rr Cameroon (1: 100,000) (separate)<br />
List <strong>of</strong> aerial photographs 1983 - 1985, 1:20,000 series covering <strong>the</strong> TCP<br />
research area (Photo sur Inc.) .................................. 81<br />
<strong>II</strong>I Methods for chemical and physical soil analysis . . . . . . . . . . . . . . . . . . . . .. 83<br />
IV Soil pr<strong>of</strong>ile descriptions and data <strong>of</strong> analysis ........................ 89<br />
V Vegetation data ......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 139<br />
VI List <strong>of</strong> bird species observed in <strong>the</strong> TCP research area. . . . . . . . . . . . . . . .. 161<br />
7
PREFACE<br />
ABOUT TROPENBOS<br />
The Trop<strong>en</strong>bos Foundation was established in 1988 by <strong>the</strong> Governm<strong>en</strong>t <strong>of</strong> The Ne<strong>the</strong>rlands with<br />
<strong>the</strong> objectives to contribute to <strong>the</strong> conservation and wise use <strong>of</strong> tropical rain forest by g<strong>en</strong>erating<br />
knowledge and developing methodologies, and to involve and str<strong>en</strong>gth<strong>en</strong> local research<br />
institutions and capacity in relation to tropical rain forests.<br />
The Trop<strong>en</strong>bos Programme carries out research on moist tropical forest land at various locations<br />
around <strong>the</strong> world. At pres<strong>en</strong>t (semi-) perman<strong>en</strong>t research sites are located in Colombia, Guyana,<br />
Indonesia, Cote d'Ivoire and Cameroon. At <strong>the</strong> differ<strong>en</strong>t locations, research programmes follow<br />
an interdisciplinary and common overall approach, with <strong>the</strong> aim to exchange data and make<br />
results mutually comparable.<br />
ABOUT THE TROPENBOS-CAMEROON PROGRAMME AND <strong>ITTO</strong> PROJECT PD<br />
26/92<br />
The pres<strong>en</strong>t publication has be<strong>en</strong> produced in <strong>the</strong> framework <strong>of</strong> <strong>ITTO</strong> Project PD 26/92, which<br />
is an integral part <strong>of</strong> <strong>the</strong> Trop<strong>en</strong>bos-Cameroon Programme (TCP). The research on which this<br />
publication is based, was financed by <strong>the</strong> International Tropical Timber Organization (<strong>ITTO</strong>), <strong>the</strong><br />
Common Fund for Commodities (CFC), <strong>the</strong> Directorate G<strong>en</strong>eral for International Cooperation<br />
<strong>of</strong> The Ne<strong>the</strong>rlands' Ministry <strong>of</strong> Foreign Affairs (DGIS), <strong>the</strong> Trop<strong>en</strong>bos Foundation and <strong>the</strong><br />
implem<strong>en</strong>ting ag<strong>en</strong>cies m<strong>en</strong>tioned below.<br />
The Trop<strong>en</strong>bos-Cameroon 'Programme was established in 1992 by <strong>the</strong> Cameroonian Ministry <strong>of</strong><br />
Environm<strong>en</strong>t and Forests (MINEF) and <strong>the</strong> Trop<strong>en</strong>bos Foundation. The g<strong>en</strong>eral objective <strong>of</strong> TCP<br />
is to develop methods and strategies for natural forest managem<strong>en</strong>t directed at sustainable<br />
production <strong>of</strong> timber and o<strong>the</strong>r forest products and services. These methods have to be<br />
ecologically sound, socially acceptable and economically viable (Foahom and Jonkers, 1992).<br />
TCP consists <strong>of</strong> fourte<strong>en</strong> interrelated projects in <strong>the</strong> fields <strong>of</strong> ecology, forestry, economy, social<br />
sci<strong>en</strong>ces, agronomy and soil sci<strong>en</strong>ce. In 1994, <strong>ITTO</strong> and CFC decided to co-finance six <strong>of</strong> <strong>the</strong>se<br />
projects, which toge<strong>the</strong>r form <strong>ITTO</strong> project PD 26/92. The 'Office National de Developpem<strong>en</strong>t<br />
des Forets' (ONADEF) is <strong>the</strong> ag<strong>en</strong>cy responsible towards <strong>ITTO</strong> and CFC for <strong>the</strong> implem<strong>en</strong>tation<br />
<strong>of</strong> <strong>the</strong> Project PD 26/92.<br />
The implem<strong>en</strong>ting ag<strong>en</strong>cies involved in <strong>the</strong> pres<strong>en</strong>t study are <strong>the</strong> Winand Staring C<strong>en</strong>tre for<br />
Integrated land, Soil and Water Research (SC-DLO), <strong>the</strong> 'Institut de la Recherche Agricole pour<br />
le Developpem<strong>en</strong>t' (lRAD) and Wag<strong>en</strong>ing<strong>en</strong> Agricultural University (WAU).<br />
ACKNOWLEDGEMENTS<br />
The authors wish to thank those who have contributed to <strong>the</strong> overall land inv<strong>en</strong>tory <strong>of</strong> <strong>the</strong> TCP<br />
research area. We gratefully acknowledge <strong>the</strong> assistance <strong>of</strong> <strong>the</strong> Cameroonian Ministry <strong>of</strong><br />
Environm<strong>en</strong>t and Forests, <strong>the</strong> Trop<strong>en</strong>bos Foundation, <strong>the</strong> 'Office National de Developpem<strong>en</strong>t des<br />
Forets', <strong>the</strong> 'Institut de la Recherche Agricole pour le Developpem<strong>en</strong>t', <strong>the</strong> International Tropical<br />
Timber Organization, <strong>the</strong> Common Fund for Commodities, <strong>the</strong> Winand Staring C<strong>en</strong>tre for<br />
9
Integrated Land, Soil and Water Research, Wag<strong>en</strong>ing<strong>en</strong> Agricultural University and <strong>the</strong><br />
Directorate G<strong>en</strong>eral for for International Cooperation <strong>of</strong> The Ne<strong>the</strong>rlands' Ministry <strong>of</strong> Foreign<br />
Affairs.<br />
Moreover, we could could not go go on without without m<strong>en</strong>tioning <strong>the</strong> <strong>the</strong> following persons persons for <strong>the</strong>ir undisputed undisputed<br />
efforts. First <strong>of</strong> all we like to thank our supervisors Patrick Hommel and Arie van Kekem <strong>of</strong> sc<br />
DLO for <strong>the</strong>ir support, <strong>en</strong>couragem<strong>en</strong>t and valuable comm<strong>en</strong>ts in <strong>the</strong> differ<strong>en</strong>t stages <strong>of</strong> <strong>the</strong><br />
project.<br />
Messrs. Wim van Driel, Oscar Eyog Matig, Bernard Foahom, Wyb Jonkers and Jean-Paul<br />
M<strong>en</strong>douga Tsimi <strong>of</strong> <strong>the</strong> TCP managem<strong>en</strong>t team are acknowledged for <strong>the</strong>ir administrative,<br />
logistic and sci<strong>en</strong>tific support.<br />
Maurice Elad, Joseph Ohandza Minkoulou, Dieudonne 'Clindor' Ndoum, Prospere Mefane<br />
and B<strong>en</strong>jamin Nkolo formed <strong>the</strong> field crew without whom <strong>the</strong>se pages would have be<strong>en</strong> empty.<br />
We are greatly indebted to Tom Bakkum and Arnold Bregt (SC-DLO) for successfully<br />
initiating <strong>the</strong> GIS in Kribi. Ms. A. St<strong>of</strong>fers is specially m<strong>en</strong>tioned for surveying <strong>the</strong> nor<strong>the</strong>rn<br />
part <strong>of</strong> <strong>the</strong> area. 'Our' stud<strong>en</strong>ts Albert Abana, Bernard Tionjock, Martijn van Gilst, Ni<strong>en</strong>ke<br />
van Berkum and Fokke de Jong have helped to advance <strong>the</strong> project in many ways. All TCP<br />
researchers, technicians, drivers and administrative personnel are thanked for <strong>the</strong>ir cordial<br />
collaboration. Martin Zogo should should be m<strong>en</strong>tioned twice for dealing with all all administrative<br />
problems that would have kept us busy for years.<br />
The National Herbarium <strong>of</strong> Cameroon Cameroon (Dr. Onana, Dr. Achoungdong, Dr. Sonke Asongonyi<br />
and and Mr. Mezili), <strong>the</strong> <strong>the</strong> Limbe Botanic Botanic Gard<strong>en</strong> (Mr. Peguy Mbatchou), <strong>the</strong> Departm<strong>en</strong>t Departm<strong>en</strong>t <strong>of</strong> Plant<br />
Taxonomy <strong>of</strong> <strong>the</strong> Wag<strong>en</strong>ing<strong>en</strong> Wag<strong>en</strong>ing<strong>en</strong> Agricultural University (Dr. Breteler and and Dr. Dr. Jongkind) and Dr.<br />
Duncan Thomas have helped with with plant plant species id<strong>en</strong>tification. Mr. Mr. Tchu<strong>en</strong>teu <strong>of</strong> <strong>the</strong> IRAD IRAD<br />
Ekona soil laboratory has conducted <strong>the</strong> majority <strong>of</strong> soil analyses. Mr. van Reeuwijk <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong><br />
International Soil Refer<strong>en</strong>ce and and Information Information C<strong>en</strong>tre (ISRIC) carried out out <strong>the</strong> clay mineralogy<br />
and refer<strong>en</strong>ce analyses.<br />
10
SUMMARY<br />
This report pres<strong>en</strong>ts <strong>the</strong> results <strong>of</strong> <strong>the</strong> reconnaissance scale landscape ecological survey <strong>of</strong> <strong>the</strong><br />
Trop<strong>en</strong>bos-Cameroon Programme (TCP) research area in Southwest Cameroon conducted by<br />
<strong>the</strong> Forest Land Inv<strong>en</strong>tory and Land Evaluation project (Lul). The main objective <strong>of</strong> <strong>the</strong> Lul<br />
project is to provide a sci<strong>en</strong>tific framework for sustainable land use planning in <strong>the</strong> TCP<br />
research area. Moreover, <strong>the</strong> Lul project provides a basis for all ecologically ori<strong>en</strong>ted research<br />
activities within <strong>the</strong> TCP area and allows for <strong>the</strong> extrapolation <strong>of</strong> <strong>the</strong> research results from<br />
sample areas to larger areas in South Cameroon.<br />
In its first phase a survey <strong>of</strong> <strong>of</strong> landforms, soils and vegetation is conducted at scale 1: 100,000 <strong>of</strong><br />
<strong>the</strong> <strong>Bipindi</strong> - <strong>Akom</strong> 11 11- - Lolodorf region (167,000 ha). Some 250 soil augerings, 45 soil pits and<br />
125 vegetation releves have be<strong>en</strong> described, covering <strong>the</strong> most important landscapes. The results<br />
<strong>of</strong> <strong>the</strong> analysis <strong>of</strong> landform, soil and vegetation data are pres<strong>en</strong>ted in this report and on <strong>the</strong><br />
landscape ecological map. The second phase <strong>of</strong> <strong>the</strong> project <strong>en</strong>tails <strong>the</strong> developm<strong>en</strong>t <strong>of</strong> a land<br />
evaluation methodology for tropical moist forests in South Cameroon.<br />
Landforms discerned in <strong>the</strong> TCP research area are mountains, complexes <strong>of</strong> hills, isolated hills,<br />
hilly and rolling uplands, dissected erosional plains, and floodplains. They are classified on basis<br />
<strong>of</strong> slope steepness, slope l<strong>en</strong>gth, relief int<strong>en</strong>sity and number <strong>of</strong> interfluves. The mountains,<br />
complexes <strong>of</strong> hills and isolated hills have very steep slopes and high relief int<strong>en</strong>sities, whereas<br />
both <strong>the</strong> uplands and <strong>the</strong> dissected erosional plains have g<strong>en</strong>tle to moderately steep slopes and low<br />
relief int<strong>en</strong>sities. The first landform group is <strong>the</strong>refore more vulnerable to erosion than <strong>the</strong> latter.<br />
, The following four soil types are dominating in <strong>the</strong> research area:<br />
well drained drained very clayey soils: soils: Nyangong soils;<br />
well drained clayey soils: <strong>the</strong> Ebom soils;<br />
- moderately well to well drained sandy loam to sandy clay soils: <strong>the</strong> Ebimimbang soils;<br />
- very poorly to poorly drained soils: <strong>the</strong> Valley Bottom soils.<br />
The Nyangong and Ebom soils are deeply wea<strong>the</strong>red yellowish brown to strong brown tropical clay<br />
soils, low in wea<strong>the</strong>rable minerals and with cation exchange capacities in <strong>the</strong> (ferralic) B-horizons<br />
<strong>of</strong> less than 16 mell 00 g clay. Their dominant clay minerals are kaolinite. The Nyangong soils<br />
have 50-80% clay in <strong>the</strong> subsoils; <strong>the</strong> Ebom soils are less heavy with 35-60% clay. Moreover,<br />
topsoils <strong>of</strong> <strong>the</strong> latter are lighter (20-50% clay) than <strong>the</strong> subsoils. The Nyangong soils classify as<br />
Xanthic Ferralsols, <strong>the</strong> Ebom soils as Acri-xanthic Ferralsols. The Ebimimbang soils are<br />
moderately deep to very deep, yellowish brown, sandy clay loams to sandy clays with lighter<br />
textured topsoils. They are classified as Plinthudults and typic Paleudults. The very poorly to<br />
poorly drained soils are developed in unconsolidated, stratified, rec<strong>en</strong>t alluvium. They are<br />
characterized by high groundwater tables, periodic flooding and locally greyish colours. In <strong>the</strong><br />
FAO-Unesco classification <strong>the</strong>y are classified as Dystric Fluvisols and Gleyic Cambisols.<br />
All soils in <strong>the</strong> TCP research area have low pHs and are chemically poor. Their physical<br />
characteristics are good. Removal <strong>of</strong> <strong>the</strong> forest vegetation, e.g. by int<strong>en</strong>sive logging or<br />
agriculture, will result in <strong>the</strong> physical degradation <strong>of</strong> <strong>the</strong> soil (decrease in organic matter) and<br />
<strong>the</strong> loss <strong>of</strong> nutri<strong>en</strong>ts stored in <strong>the</strong> forest vegetation.<br />
Sev<strong>en</strong> distinct 'plant communities' have be<strong>en</strong> id<strong>en</strong>tified using a phytosociological approach; <strong>the</strong><br />
analysis <strong>of</strong> plot data was carried out with <strong>the</strong> computer programme TWINSPAN. All vegetation<br />
11
types are defined by floristic composition and <strong>the</strong> (external) foliage coverage <strong>of</strong> <strong>the</strong> species.<br />
Interpretation <strong>of</strong> successional status, overall physiognomy and g<strong>en</strong>eral site descriptors descriptors reveals<br />
a strong correlation <strong>of</strong> <strong>the</strong> plant communities with altitude and disturbance. The The communities<br />
discerned are: submontane forest (altitude> 700 m asl), three types <strong>of</strong> lowland evergre<strong>en</strong> forest<br />
« 350 m asl; 350-500 m asl; 500-700 m asl), swamp forest, young secondary forest and thicket<br />
on rec<strong>en</strong>tly abandoned agricultural fields.<br />
The leg<strong>en</strong>d <strong>of</strong> <strong>the</strong> 1: 100,000 landscape ecological map is based on altitude, landform, soil and and<br />
vegetation, and has a hierarchical hierarchical structure. A total <strong>of</strong> 14 main mapping units has be<strong>en</strong><br />
discerned. These These 14 units have be<strong>en</strong> fur<strong>the</strong>r fur<strong>the</strong>r subdivided according to vegetation characteristics<br />
brought about by human human influ<strong>en</strong>ces (shifting (shifting cultivation) into 34 units. The landscape ecological ecological<br />
map pres<strong>en</strong>ts <strong>the</strong> landscape in in its complexity <strong>of</strong> landforms, soils and vegetation. Cross refer<strong>en</strong>ce<br />
<strong>of</strong> <strong>the</strong> inv<strong>en</strong>tory data reveals a strong strong relationship betwe<strong>en</strong> vegetation, altitude and soils. This<br />
supports <strong>the</strong> notion that natural vegetation can be se<strong>en</strong> as a response variable to to <strong>en</strong>vironm<strong>en</strong>tal<br />
factors such as climate and soil. Since vegetation proves to be correlated with altitude, which<br />
is assumed to be related to climatic factors, <strong>the</strong> latter has be<strong>en</strong> tak<strong>en</strong> as <strong>the</strong> highest <strong>en</strong>try <strong>of</strong> <strong>the</strong><br />
map' leg<strong>en</strong>d. On this basis, <strong>the</strong> TCP research area is divided into five ecological zones (A-E).<br />
The overall ori<strong>en</strong>tation <strong>of</strong> <strong>the</strong> ecological zones is NNE-SSW and follows <strong>the</strong> g<strong>en</strong>eral ori<strong>en</strong>tation<br />
<strong>of</strong> <strong>the</strong> geological structures in Southwest Cameroon. The landscape <strong>of</strong> <strong>the</strong> TCP research area<br />
changes changes considerably from from west to east. east. Altitude rises from approximately 40 40 to over 1000 m<br />
as!. asl. Dissected erosional plains, hilly and rolling uplands dominate <strong>the</strong> western part <strong>of</strong> <strong>the</strong> area<br />
whereas complexes <strong>of</strong> hills and mountains are found solely in <strong>the</strong> east. Going from west to east<br />
<strong>the</strong> soils change from Ebimimbang to Ebom and Nyangong <strong>the</strong>reby increasing in clay cont<strong>en</strong>t.<br />
Valley bottoms are found throughout <strong>the</strong> area but are more frequ<strong>en</strong>t and wider in <strong>the</strong> west. The<br />
natural vegetation changes from low altitude evergre<strong>en</strong> forest with many littoral species to a<br />
submontane vegetation with characteristics <strong>of</strong> cloud forest. Human activities have influ<strong>en</strong>ced<br />
this gradi<strong>en</strong>t by logging and and shifting shifting cultivation. Along Along <strong>the</strong> main access roads roads and in <strong>the</strong> <strong>the</strong> vicinity<br />
<strong>of</strong> villages mosaics are found <strong>of</strong> actual actual fields, thickets on rec<strong>en</strong>tly abandoned fields, young young<br />
secondary forest and residual patches <strong>of</strong> tropical moist forest.<br />
12
1. INTRODUCTION<br />
1.1 FOREST LAND INVENTORY AND LAND EVALUATION PROJECT (LUl)<br />
The Trop<strong>en</strong>bos Cameroon Programme (TCP) coordinates fourte<strong>en</strong> interrelated projects in <strong>the</strong><br />
fields <strong>of</strong> ecology, forestry, economy, social sci<strong>en</strong>ces, agronomy and soil sci<strong>en</strong>ce. This report<br />
pres<strong>en</strong>ts <strong>the</strong> results <strong>of</strong> <strong>the</strong> reconnaissance scale land inv<strong>en</strong>tory carried out in <strong>the</strong> first phase <strong>of</strong><br />
<strong>the</strong> research project Lu1, titled 'Forest Land Inv<strong>en</strong>tory and Land Evaluation'.<br />
1.2 RESEARCH OBJECTIVES<br />
Detailed and up-to-date information on <strong>the</strong> abiotic and biotic <strong>en</strong>vironm<strong>en</strong>t <strong>of</strong> <strong>the</strong> TCP research<br />
area is a prerequisite for <strong>the</strong> formulation <strong>of</strong> a managem<strong>en</strong>t plan. This information, however, is<br />
ei<strong>the</strong>r non-exist<strong>en</strong>t (e.g. hydrology and erosion aspects) or not detailed <strong>en</strong>ough for <strong>the</strong> pres<strong>en</strong>t<br />
needs (e.g. climate, landforms, soils, land use, vegetation, and wildlife). The Lu1 Lu 1 project is<br />
aimed at filling those gaps, which is ess<strong>en</strong>tial for sound land use planning.<br />
The g<strong>en</strong>eral objective <strong>of</strong> Lu1 is to provide a sci<strong>en</strong>tific framework for sustainable land use<br />
planning for <strong>the</strong> TCP research area. This will be realized through <strong>the</strong> developm<strong>en</strong>t <strong>of</strong> a land<br />
evaluation methodology for tropical moist forests. Moreover, <strong>the</strong> Lul project provides a basis<br />
for all ecologically ori<strong>en</strong>ted research activities within <strong>the</strong> TCP and permits <strong>the</strong> extrapolation <strong>of</strong><br />
<strong>the</strong> results <strong>of</strong> TCP research to o<strong>the</strong>r areas in South Cameroon.<br />
The first phase <strong>of</strong> <strong>the</strong> Lul project <strong>en</strong>tails an integrated reconnaissance scale (1: 100,000) survey<br />
on landforms, soils and vegetation. The pres<strong>en</strong>t report is <strong>the</strong> result <strong>of</strong> this integrated survey,<br />
delimitating and describing <strong>the</strong> major landscape ecological units <strong>of</strong> <strong>the</strong> TCP area. In <strong>the</strong> second<br />
phase <strong>of</strong> <strong>the</strong> Lu1 project a qualitative ecological land evaluation will be conducted, investigating<br />
<strong>the</strong> suitability <strong>of</strong> each <strong>of</strong> <strong>the</strong> landscape ecological units for a number <strong>of</strong> relevant land-uses.<br />
1.3 COURSE OF THE STUDY<br />
Preliminary work on <strong>the</strong> interpretation <strong>of</strong> aerial photographs, including a five-week mission to<br />
<strong>the</strong> study area, was carried out by Mr. Luc Touber <strong>of</strong> <strong>the</strong> DLO- Winand Staring C<strong>en</strong>tre for<br />
Integrated Land, Soil and Water Research (SC-DLO) (Touber, 1993a; 1993b).<br />
The Directorate G<strong>en</strong>eral for International Cooperation <strong>of</strong> The Ne<strong>the</strong>rlands' Ministry <strong>of</strong> Foreign<br />
Affairs (DGIS) contracted two associate experts for <strong>the</strong> Lul project. Mr. G.W. Hazeu, soil<br />
sci<strong>en</strong>tist, started his work in Cameroon Cameroon in in March 1995. 1995. His contract expired in September 1997.<br />
In March 1995, DGIS appointed appointed Mr. Bar<strong>en</strong>d S. van Gemerd<strong>en</strong> as vegetation surveyor whose<br />
contract expired in December 1997.<br />
The fieldwork for <strong>the</strong> landform, soil and vegetation survey was carried out betwe<strong>en</strong> March 1995<br />
and May 1996. Ms. A. St<strong>of</strong>fels carried out <strong>the</strong> field survey <strong>of</strong> <strong>the</strong> nor<strong>the</strong>rn part in <strong>the</strong> period<br />
April-October 1997.<br />
Overall supervision <strong>of</strong> <strong>the</strong> Lu 1 project was provided by s<strong>en</strong>ior soil and vegetation experts <strong>of</strong> SC<br />
DLO. Additional assistance was giv<strong>en</strong> by a s<strong>en</strong>ior GIS expert <strong>of</strong> <strong>the</strong> same institute. A total <strong>of</strong><br />
13
four backstopping missions were carried out by SC-DLO during <strong>the</strong> first phase <strong>of</strong> <strong>the</strong> project<br />
(Bregt and van Kekem, 1995, Hommel, 1995; Hommel and van Kekem, 1996, 1997).<br />
<strong>Bipindi</strong><br />
100 10° 40" 40° E<br />
I<br />
1 I Lolodorf<br />
! •<br />
--)----:----t---'--1-3° --')---:----+----''---t1-3° 00" oooN N<br />
Alcom<strong>II</strong><br />
10 20lIm<br />
I !<br />
Figure 1.1 Location <strong>of</strong> TCP research area in Southwest Cameroon<br />
1.4 REPORT OUTLINE<br />
The climate, hydrology, geology, geomorphology, soils, vegetation and land use in South-West<br />
Cameroon are described in Chapter 2. The inforn.1ation pres<strong>en</strong>ted is mostly derived from national<br />
or regional studies and merely gives a g<strong>en</strong>eral overview <strong>of</strong> <strong>the</strong> physical <strong>en</strong>vironm<strong>en</strong>t <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> TCP<br />
area.<br />
To meet <strong>the</strong> needs needs <strong>of</strong> <strong>the</strong> qualitative ecological land evaluation more detailed information on<br />
landforms, soils and vegetation in <strong>the</strong> TCP area has be<strong>en</strong> collected. Chapter 3 describes <strong>the</strong><br />
methods used. Special emphasis is placed on <strong>the</strong> integration<br />
<strong>of</strong> <strong>the</strong> landform, soil and vegetation survey into what can be described as as a broad landscape<br />
ecological approach (e.g. Zonneveld, Zonneveld, 1995). In Chapters 4,5 4, 5 and 6 <strong>the</strong> results <strong>of</strong> <strong>of</strong> respectively<br />
<strong>the</strong> <strong>the</strong> landform, landform, soil and vegetation survey are pres<strong>en</strong>ted.<br />
In Chapter Chapter 7 <strong>the</strong> landscape ecological map <strong>of</strong> <strong>the</strong> TCP research area (Annex I) is discussed and<br />
its units are described as characteristic combinations <strong>of</strong> landforms, soils and vegetation types.<br />
14
2. STUDY AREA<br />
2.1 LOCATION AND INFRASTRUCTURE<br />
The TCP research area is situated in Southwest Cameroon at approximately 80 km East <strong>of</strong> Kribi,<br />
betwe<strong>en</strong> r47'-3°14' N, 10°24'-10°51' E. The area is delimitated by <strong>the</strong> villages <strong>of</strong> <strong>Bipindi</strong>,<br />
<strong>Akom</strong> <strong>II</strong> and Lolodorf (Fig. 1.1). From an administrative point <strong>of</strong> view <strong>the</strong> TCP research area<br />
is part <strong>of</strong> <strong>the</strong> South Province <strong>of</strong> <strong>the</strong> Republic <strong>of</strong> Cameroon and is subdivided into <strong>the</strong><br />
Departm<strong>en</strong>ts Ocean and Ntem. The TCP area covers about 1700 km2 The TCP research area is situated in Southwest Cameroon at approximately 80 km East <strong>of</strong> Kribi,<br />
betwe<strong>en</strong> r47'-3 ° 14' N, 10°24'-10°51' E. The area is delimitated by <strong>the</strong> villages <strong>of</strong> <strong>Bipindi</strong>,<br />
<strong>Akom</strong> <strong>II</strong> and Lolodorf (Fig. 1.1). From an administrative point <strong>of</strong> view <strong>the</strong> TCP research area<br />
is part <strong>of</strong> <strong>the</strong> South Province <strong>of</strong> <strong>the</strong> Republic <strong>of</strong> Cameroon and is subdivided into <strong>the</strong><br />
Departm<strong>en</strong>ts Ocean and Ntem. The TCP area covers about 1700 km which to a large ext<strong>en</strong>t<br />
coincides with a concession <strong>of</strong> <strong>the</strong> Dutch logging company <strong>of</strong>Wijma-Douala S.A.R.L. (GWZ).<br />
2 which to a large ext<strong>en</strong>t<br />
coincides with a concession <strong>of</strong> <strong>the</strong> Dutch logging company <strong>of</strong>Wijma-Douala S.A.R.L. (GWZ).<br />
All roads leading to and within <strong>the</strong> TCP area are dirt roads. Two governm<strong>en</strong>tal roads delimit <strong>the</strong><br />
TCP research area, <strong>the</strong> Kribi-<strong>Bipindi</strong>-Lolodorf-Ebolowa road in <strong>the</strong> northwest and <strong>the</strong> Kribi<br />
<strong>Akom</strong> <strong>II</strong>-Ebolowa road in <strong>the</strong> south. Within <strong>the</strong> area three principal roads are pres<strong>en</strong>t, two <strong>of</strong><br />
which having approximately a W-E direction and one a SW-NE direction. In addition many<br />
smaller exploitation roads have be<strong>en</strong> constructed. Accessibility <strong>of</strong> <strong>the</strong>se, however, is variable<br />
as maint<strong>en</strong>ance is carried out by <strong>the</strong> logging companies and ceases once <strong>the</strong>ir activities are<br />
transferred to o<strong>the</strong>r regions. Footpaths connecting villages are found throughout <strong>the</strong> area.<br />
Transport by boat over <strong>the</strong> rivers is not possible due to <strong>the</strong> pres<strong>en</strong>ce <strong>of</strong> rapids and waterfalls.<br />
2.2 CLIMATE<br />
The climate <strong>of</strong> Southwest Cameroon is equatorial. Although rainfall occurs throughout <strong>the</strong> year,<br />
two distinct minima and maxima can be distinguished in <strong>the</strong> annual pattern which are associated<br />
with <strong>the</strong> N-S movem<strong>en</strong>ts <strong>of</strong> <strong>the</strong> Intertropical Converg<strong>en</strong>ce Zone over <strong>the</strong> area. The humid<br />
seasons ext<strong>en</strong>d from September to November and from April to May, whereas <strong>the</strong> drier seasons<br />
ext<strong>en</strong>d from December to March and from June to August. According to <strong>the</strong> classification<br />
system <strong>of</strong>K6pp<strong>en</strong> (1936), <strong>the</strong> climate <strong>of</strong> <strong>the</strong> area is classified as humid tropical (Aw). Such a<br />
climate has a mean temperature in <strong>the</strong> coldest month above 18°C, an average annual temperature<br />
<strong>of</strong> around 25°C 25 ° C with little variation betwe<strong>en</strong> years, and at least one distinct dry season.<br />
Table 2.1 Summary <strong>of</strong> climatic data for selected stations in Southwest Cameroon (Olivry,<br />
1986)<br />
Climatic data Wea<strong>the</strong>r station<br />
Kribi Lolodorf Ebolowa<br />
Altitude (m asl) as!) 13 440 609<br />
Mean Mean annual annual temperature temperature Cc) 26.4 24.6 24.0<br />
Mean annual relative humidity (%) 73-94 n.a. 68-97<br />
Mean annual vapour pressure (mbar) 29.3 n.a. 24.6<br />
Mean annual rainfall (mm) 2836 (±393) 2096 (±286) 1719 (±195)<br />
Wind speed below 4 m S·I (% <strong>of</strong> time) 98 n.a. n.a.<br />
Main wind direction SW n.a. W<br />
Kribi n= 45 years; Lolodorf n= 25 years; Ebolowa n= 48 years; n.a. = data not available.<br />
A summary <strong>of</strong> climatic data <strong>of</strong> selected stations in <strong>the</strong> region is pres<strong>en</strong>ted in Table 2.1. The long<br />
term annual mean temperature decreases from West to East, corresponding with an increase in<br />
altitude altitude (Olivry, (Olivry, 1986).<br />
15
Long-term averages <strong>of</strong> monthly rainfall totals <strong>of</strong> <strong>the</strong> Kribi, Lolodorf and Ebolowa stations are<br />
pres<strong>en</strong>ted in Fig. 2.2. Due to <strong>the</strong> geographic position <strong>of</strong> <strong>the</strong> TCP research area, <strong>the</strong> rainfall<br />
pattern in <strong>the</strong> area is likely to resemble those at Lolodorf and Ebolowa, ra<strong>the</strong>r than that at Kribi.<br />
Wind speeds are g<strong>en</strong>erally low and <strong>the</strong> direction is predominantly W-SW throughout <strong>the</strong> year<br />
(Dolman and Waterloo, 1995).<br />
The duration <strong>of</strong> bright sunshine has not be<strong>en</strong> measured at any <strong>of</strong> <strong>the</strong> wea<strong>the</strong>r stations in South<br />
Cameroon. However, <strong>the</strong> mean daily value <strong>of</strong> 3.4 h day-! observed at <strong>the</strong> wea<strong>the</strong>r station in<br />
Douala is a fair approximation (Dolman and Waterloo, 1995).<br />
2.3 HYDROLOGY<br />
The hydrography <strong>of</strong> Southwest Cameroon is characterized by a high drainage d<strong>en</strong>sity as a result<br />
<strong>of</strong> a humid climate and <strong>the</strong> low permeability <strong>of</strong> <strong>the</strong> crystalline rock formations (Franqueville,<br />
1973). The main rivers draining <strong>the</strong> TCP research area are <strong>the</strong> Lokoundje, Tchangue, Ki<strong>en</strong>ke,<br />
Moungue, Biwome, Sonkwe and Messambe. Their flow direction is g<strong>en</strong>erally NNE-SSW,<br />
following <strong>the</strong> regional pattern <strong>of</strong> faulting. Smaller streams have a flow direction ess<strong>en</strong>tially<br />
perp<strong>en</strong>dicular to <strong>the</strong> main rivers, resulting in a drainage pattern that has both d<strong>en</strong>dritic and<br />
trellised characteristics.<br />
Swampy areas are commonly found in <strong>the</strong> valleys <strong>of</strong> <strong>the</strong> smaller rivers. The soils in <strong>the</strong>se areas<br />
, remain waterlogged ev<strong>en</strong> during dry periods due to a continuous supply <strong>of</strong> groundwater from<br />
<strong>the</strong> hill slopes and due to relatively thin valley soils underlain by massive rock <strong>of</strong> low<br />
permeability.<br />
;:Prior ;: Prior to 1995, hydrological studies have not be<strong>en</strong> carried out at any location within <strong>the</strong> TCP<br />
research area. Hydrometric stations <strong>of</strong> <strong>the</strong> 'C<strong>en</strong>tre de Recherches Hydrologiques' <strong>of</strong> <strong>the</strong><br />
'Institute de Recherche Geologique et Miniere' (CRH-IRGM) were located in Lolodorf in <strong>the</strong><br />
Lokoundje river (draining <strong>the</strong> area north <strong>of</strong> <strong>the</strong> TCP research area) and in <strong>the</strong> Ki<strong>en</strong>ke river<br />
(partly draining <strong>the</strong> TCP research area) and <strong>the</strong> Lobe river (draining <strong>the</strong> area south <strong>of</strong> <strong>the</strong> TCP<br />
research area) at Kribi. However, all stations in South Cameroon have be<strong>en</strong> abandoned since<br />
1987 (pers. comm. J.c. J.C. Ntonga, 1996).<br />
The discharge patterns <strong>of</strong> <strong>the</strong> rivers correspond to <strong>the</strong> seasonal rainfall pattern with maxima in<br />
October and May and minima in August and February (Olivry, 1986). Fig. 2.2 shows <strong>the</strong> monthly<br />
discharges <strong>of</strong> <strong>the</strong> Lokoundje, Ki<strong>en</strong>ke and Lobe rivers for <strong>the</strong> 1953 -1977 period.<br />
The average annual discharge <strong>of</strong> <strong>the</strong> Lokoundje river (at Lolodorf) amounted to 773 mm,<br />
whereas those <strong>of</strong> <strong>the</strong> Ki<strong>en</strong>ke and Lobe rivers amounted to 1082 mm and 1397 mm, respectively.<br />
Rainfall on <strong>the</strong> Lokoundje basin and <strong>the</strong> Ki<strong>en</strong>ke and Lobe basins could be estimated at 1880 mm<br />
and 2425 mm, respectively, resulting in run<strong>of</strong>f coeffici<strong>en</strong>ts varying betwe<strong>en</strong> 41 % for <strong>the</strong> Lokoundje<br />
basin and 45% and 58% for <strong>the</strong> Ki<strong>en</strong>ke and Lobe basins (Olivry, 1986).<br />
Annual evaporation rates obtained with <strong>the</strong> water balance method varied betwe<strong>en</strong> 1107 mm for<br />
<strong>the</strong> Lokoundje basin and 1345 mm and 1025 mm for <strong>the</strong> Ki<strong>en</strong>ke and Lobe basins (Olivry, 1986).<br />
The electric conductivity <strong>of</strong> stream water in <strong>the</strong> TCP research area is extremely low and varies<br />
betwe<strong>en</strong> 13 IlS cm-! and 28 IlS cm-! in <strong>the</strong> dry season (Dolman and Waterloo, 1995). On <strong>the</strong><br />
basis <strong>of</strong> data collected in one rainy season two EC zones can be discerned, <strong>the</strong> eastern part <strong>of</strong><br />
17
The Ntem complex is comparable to to <strong>the</strong> Calcium-magnesium complex. The The Nyong series consist<br />
<strong>of</strong> meta-sedim<strong>en</strong>tary rocks which are are composed <strong>of</strong> migmitates, gneiss, quartzites quartzites and<br />
amphibolites. In addition, in in <strong>the</strong> Lolodorf region, some small l<strong>en</strong>ses <strong>of</strong> ferro-magnesian rocks rocks<br />
are found, such as amphibolites, diorites and gabbros, forming discontinuous bands bands with a<br />
g<strong>en</strong>eral NE-SW direction.<br />
During <strong>the</strong> pres<strong>en</strong>t survey, mainly mainly gneisses <strong>of</strong> various composition were found, as well as locally<br />
granites, migmatites, migmatites, amphibolites, diorites and gabbros. Soils developed under a humid humid tropical<br />
climate climate on <strong>the</strong>se metamorphic metamorphic and igneous rocks will be composed <strong>of</strong> clay clay minerals (mainly<br />
kaolinite) with quartz quartz sand and iron(hydr)oxides. These soils soils are acid and have low nutri<strong>en</strong>t<br />
cont<strong>en</strong>ts.<br />
The overall tectonic direction in <strong>the</strong> Basem<strong>en</strong>t complex is NNE-SSW. Two synclinal zones and<br />
one anticlinal zone can be distinguished in South Cameroon. The first synclinal zone coincides<br />
ess<strong>en</strong>tially with <strong>the</strong> Sanaga valley, <strong>the</strong> second occupies Cameroon's sou<strong>the</strong>rn border and and<br />
disappears under <strong>the</strong> coastal coastal basins. The anticlinal structure is composed <strong>of</strong> <strong>the</strong> metamorphic<br />
complex <strong>of</strong>Ntem which forms an ext<strong>en</strong>sion <strong>of</strong> <strong>the</strong> Ebolowa-Ambam granite zone (Franqueville,<br />
1973).<br />
Mineral resources <strong>of</strong> <strong>the</strong> geological formations in this part <strong>of</strong> <strong>the</strong> country are not economically<br />
exploitable (Franqueville, 1973).<br />
2.5 GEOMORPHOLOGY<br />
The Atlantic coast <strong>of</strong> Southwest Cameroon is characterized by large swampy areas in <strong>the</strong> Douala<br />
basin while southwards a rocky coastline is pres<strong>en</strong>t. Going eastward, <strong>the</strong> landscape changes from<br />
low altitude sedim<strong>en</strong>tary plains to erosional plains and plateaus <strong>of</strong> <strong>the</strong> Precambrian shield with<br />
altitudes betwe<strong>en</strong> 600 and and 1000 m as!. The interface betwe<strong>en</strong> <strong>the</strong> sedim<strong>en</strong>tary plain and <strong>the</strong><br />
Precambrian shield is only revealed by a few rapids in <strong>the</strong> larger rivers. Within <strong>the</strong> Precambrian<br />
shield four erosional plateaus, corresponding with 100, 200-300, 400-500 and 600-800 m asl,<br />
can can be distinguished. The plateaus plateaus at 200-300 and 600-800 600-800 m asl respectively, correspond with<br />
<strong>the</strong> erosion surfaces African <strong>II</strong> and I (Franqueville, 1973).<br />
Fluvial processes have have shaped shaped <strong>the</strong> landforms in <strong>the</strong> rec<strong>en</strong>t past. Eolian, glacial or or periglacial<br />
processes did did not affect <strong>the</strong> <strong>the</strong> Cameroonian Precambrian shield.<br />
The TCP research area is on <strong>the</strong> transition betwe<strong>en</strong> <strong>the</strong> coastal coastal plain and <strong>the</strong> Precambrian Precambrian shield shield<br />
forming <strong>the</strong> interior plateau (Segal<strong>en</strong>, (Segal<strong>en</strong>, 1967). As a result <strong>the</strong> TCP TCP research area is<br />
geomorphologically geomorphologically diverse. In <strong>the</strong> western western part plains dominate dominate whereas whereas <strong>the</strong> eastern part is<br />
mountainous. The altitude ranges from 40 m asl in <strong>the</strong> western part to more than 1000 m asl in<br />
<strong>the</strong> eastern part. The c<strong>en</strong>tral area is intermediate in both landform and altitude. A more elaborate<br />
literature review on landforms in <strong>the</strong> TCP research area is pres<strong>en</strong>ted in section 4.1.<br />
2.6 SOILS<br />
The soils <strong>of</strong> Southwest Cameroon have be<strong>en</strong> described and mapped at scale 1 :2,000,000 and<br />
1: 1,000,000 (Segal<strong>en</strong>, 1957; Martin and Segal<strong>en</strong>, 1966). Three major soil types are<br />
distinguished. The deep, moderately well to well drained, yellowish brown tropical clay soils;<br />
'les sols ferrallitiquesjaunes sur les roches acides (gneiss)' in <strong>the</strong> original Fr<strong>en</strong>ch d<strong>en</strong>omination,<br />
20
Because <strong>of</strong> <strong>the</strong> various human activities m<strong>en</strong>tioned above, <strong>the</strong> vegetation in large parts <strong>of</strong><br />
Southwest Cameroon has changed drastically. Forests in differ<strong>en</strong>t stages <strong>of</strong> degradation are found<br />
close to towns and villages, along access roads, and in logged forest. The floristic composition <strong>of</strong><br />
<strong>the</strong> secondary vegetation is very distinct and incorporates many species which can be characterized<br />
as 'pioneer species' and which are found in disturbed vegetation throughout <strong>the</strong> Guineo-Congolian<br />
domain, e.g. Musanga cecropioides, Myrianthus arboreus and Homalium species. Large rec<strong>en</strong>t<br />
clearings are typically overgrown with <strong>the</strong> stout herb Chromola<strong>en</strong>a odorata. Moreover, dep<strong>en</strong>ding<br />
on <strong>the</strong> int<strong>en</strong>sity <strong>of</strong> clearing, many relicts <strong>of</strong> <strong>the</strong> previous forests are found reflecting <strong>the</strong><br />
characteristics <strong>of</strong> each <strong>of</strong> <strong>the</strong> phytogeographic districts.<br />
A more elaborate literature review on vegetation in <strong>the</strong> TCP research area is giv<strong>en</strong> in section 6.1.<br />
2.8 WILDLIFE<br />
The tropical moist forest area <strong>of</strong> Cameroon possesses high levels <strong>of</strong> <strong>en</strong>demic fauna and flora.<br />
The Lower Guinea c<strong>en</strong>tre <strong>of</strong> <strong>en</strong>demism (Gartlan, 1989) stretches from SE Nigeria in <strong>the</strong> north<br />
to Gabon in <strong>the</strong> south. A subdivision is made into <strong>the</strong> Cameroon refuge, c<strong>en</strong>tring around Mount<br />
Cameroon, and <strong>the</strong> West Equatorial refuge south <strong>of</strong> <strong>the</strong> Sanaga river. The two refuges are<br />
important with respect to <strong>the</strong> conservation <strong>of</strong> biodiversity.<br />
Approximately 132 species <strong>of</strong> mammals are found in <strong>the</strong> humid forests <strong>of</strong>Cameroon <strong>of</strong> Cameroon (Vivi<strong>en</strong>,<br />
1991), among which <strong>en</strong>dangered species like elephant (Loxodonta africana cyc/otis), cyclotis), western<br />
lowland gorilla (Gorilla gorilla gorilla), chimpanzee (Pan-troglodytes troglodytes), mandrill<br />
(Mandrillus sphinx), African leopard (Pan<strong>the</strong>ra pardus), forest buffalo (Synceras caffer nanus)<br />
and bongo (Tragelaphus eurycerus) (IUCN, 1988). No systematic c<strong>en</strong>sus <strong>of</strong> <strong>the</strong> mammals <strong>of</strong> <strong>the</strong><br />
;;rCP area has tak<strong>en</strong> place. Van Dijk (1997), in her study on non-timber forest products,<br />
. interviewed villagers on <strong>the</strong> use and pres<strong>en</strong>ce <strong>of</strong> <strong>of</strong>' 'bush bush meat'. Her survey reveals that, although<br />
<strong>the</strong> elephant has become extinct, <strong>the</strong> TCP research area still harbours gorillas, chimpanzees and<br />
mandrills. Bekhuis (1997) studied, within <strong>the</strong> framework <strong>of</strong> <strong>the</strong> Lu 1 project, <strong>the</strong> habitat<br />
:requirem<strong>en</strong>ts <strong>of</strong> some larger mammal species.<br />
Some 849 species <strong>of</strong> birds are found in Cameroon (Louette, 1981). A total <strong>of</strong>390 bird species<br />
are known to occur in <strong>the</strong> Korup National park and its surroundings in <strong>the</strong> South-West Province,<br />
Cameroon. Although <strong>the</strong> avifauna <strong>of</strong> this area is still incompletely known, it is already among<br />
<strong>the</strong> ornithologically most diverse lowland forest sites in Africa (Rodewald et et al., 1994). Some<br />
48 <strong>of</strong> <strong>the</strong>se species are considered globally threat<strong>en</strong>ed or near-threat<strong>en</strong>ed. The avifauna <strong>of</strong> <strong>the</strong><br />
TCP research area has nei<strong>the</strong>r be<strong>en</strong> studied int<strong>en</strong>sively nor systematically. The legacy <strong>of</strong> a few<br />
individuals has resulted in <strong>the</strong> drafting <strong>of</strong> a preliminary species list <strong>of</strong> <strong>the</strong> TCP research area.<br />
The total <strong>of</strong> id<strong>en</strong>tified species is at pres<strong>en</strong>t 96. In Annex VI all recorded species are listed.<br />
2.9 POPULATION<br />
The human population <strong>of</strong> Southwest Cameroon is conc<strong>en</strong>trated in a few urban c<strong>en</strong>tres like Edea,<br />
Kribi and Ebolowa, and in numerous villages along <strong>the</strong> main access roads. Population d<strong>en</strong>sity<br />
in <strong>the</strong> rural forest areas averages 5 habitants per km 2 The human population <strong>of</strong> Southwest Cameroon is conc<strong>en</strong>trated in a few urban c<strong>en</strong>tres like Edea,<br />
Kribi and Ebolowa, and in numerous villages along <strong>the</strong> main access roads. Population d<strong>en</strong>sity<br />
in <strong>the</strong> rural forest areas averages 5 habitants per km (Foahom and Jonkers, 1992).<br />
2 (Foahom and Jonkers, 1992).<br />
The ethnic composition <strong>of</strong> <strong>the</strong> population <strong>of</strong> <strong>the</strong> TCP research area is diverse. Approximately<br />
90% <strong>of</strong> <strong>the</strong> population are Bantus, belonging to <strong>the</strong> Bulu, Fang, Bassa and Ngumba tribes. They<br />
live in villages along <strong>the</strong> roads. The Bantus practice shifting cultivation, but o<strong>the</strong>r activities such<br />
23
as hunting, fishing and ga<strong>the</strong>ring <strong>of</strong> Non Timber Forest Products (NTFPs) are also important.<br />
Approximately five perc<strong>en</strong>t <strong>of</strong> <strong>of</strong><strong>the</strong> <strong>the</strong> population are Bakola (or Bagyeli) pygmies. They are mainly<br />
forest dwelling hunters and ga<strong>the</strong>rers, although <strong>the</strong>y seem to be in <strong>the</strong> process <strong>of</strong> sed<strong>en</strong>tarization.<br />
Shifting Shifting cultivation is practised by Bakola but is not not widespread. The The life style <strong>of</strong> <strong>the</strong> <strong>the</strong> Bakola Bakola is<br />
seriously threat<strong>en</strong>ed threat<strong>en</strong>ed by <strong>the</strong> ongoing logging and shifting cultivation activities in <strong>the</strong> <strong>the</strong> area.<br />
Traditionally Bantu and Bakola have all sorts <strong>of</strong> socio-economic relationships. Bakola groups<br />
have kinship ties with certain villages which arranges <strong>the</strong> mutual use <strong>of</strong> forest areas and protects<br />
it from outsiders. Bakola provide agricultural labour and bush meat to <strong>the</strong> Bantu farmers in<br />
return for agricultural products, like cassava and bananas, and increasingly for money. Bakola<br />
traditional doctors are regularly consulted by <strong>the</strong> Bantu villagers. In rec<strong>en</strong>t years <strong>the</strong> relation <strong>of</strong><br />
<strong>the</strong> Bakola with <strong>the</strong>ir Bantu kin is becoming less exclusive and Bakola are now known to sell<br />
NTFPs directly directly to traders traders outside <strong>the</strong> region (pers. comm., F. Tiayon, 1996).<br />
Traditionally Traditionally m<strong>en</strong> and wom<strong>en</strong> <strong>of</strong> rural rural communities <strong>of</strong> Southwest Cameroon have specific tasks<br />
with regard regard to land use. use. In Bantu Bantu villages, <strong>the</strong> wom<strong>en</strong> are responsible for <strong>the</strong> cultivation <strong>of</strong><br />
crops, <strong>the</strong> <strong>the</strong> preparation <strong>of</strong> food and <strong>the</strong> <strong>the</strong> g<strong>en</strong>eral housekeeping. M<strong>en</strong> are responsible for <strong>the</strong><br />
clearing clearing <strong>of</strong> forest and old forest fallow for agricultural fields, hunting and <strong>the</strong> cultivation <strong>of</strong> cash<br />
crops. Labour provision to logging and o<strong>the</strong>r companies is restricted to m<strong>en</strong>. The collection <strong>of</strong><br />
NTFPs in <strong>the</strong> vicinity <strong>of</strong> <strong>the</strong> village and fields is done by wom<strong>en</strong>, whereas those from <strong>the</strong> virgin<br />
forest are ga<strong>the</strong>red by m<strong>en</strong>.<br />
A gradual transformation <strong>of</strong> <strong>the</strong> rural communities communities from subsist<strong>en</strong>ce to (partially) market<br />
ori<strong>en</strong>ted ori<strong>en</strong>ted economy, economy, is taking place in <strong>the</strong> last last decade and is strongly influ<strong>en</strong>ced by <strong>the</strong> improved improved<br />
infrastructure. This This will trigger changes in <strong>the</strong> relation betwe<strong>en</strong> betwe<strong>en</strong> m<strong>en</strong> m<strong>en</strong> and wom<strong>en</strong> and as as a result<br />
<strong>the</strong> <strong>the</strong> dynamics <strong>of</strong> land utilization by <strong>the</strong> local population may change (pers. comm., I. Hijman,<br />
1996).<br />
2.10 LAND USE<br />
The main economic activity in <strong>the</strong> area is timber exploitation. Most <strong>of</strong> <strong>the</strong> forest within <strong>the</strong> TCP<br />
research area has at least twice be<strong>en</strong> selectively logged by national and international companies,<br />
among <strong>the</strong>m <strong>the</strong> Dutch GWZ. Logging concessions are granted for a one to three year period.<br />
The logging <strong>of</strong> <strong>the</strong> forest involves <strong>the</strong> construction <strong>of</strong> logging roads with bulldozers and graders.<br />
Log extraction from <strong>the</strong> forest is done by wheeled skidders and crawler tractors. Pres<strong>en</strong>t logging<br />
activities focus on three species; Azobe (Lophira alata), 60% <strong>of</strong> <strong>the</strong> extracted volume), Tali<br />
(Erythrophleum ivor<strong>en</strong>se) and Padouk (Pterocarpus soyauxii). Only trees with diameters at<br />
breast height (dbh) z 80 cm and straight boles <strong>of</strong> at least six meters are considered worthwhile.<br />
The resulting average logging int<strong>en</strong>sity is low, i.e. 10 m3 ha- l The main economic activity in <strong>the</strong> area is timber exploitation. Most <strong>of</strong> <strong>the</strong> forest within <strong>the</strong> TCP<br />
research area has at least twice be<strong>en</strong> selectively logged by national and international companies,<br />
among <strong>the</strong>m <strong>the</strong> Dutch GWZ. Logging concessions are granted for a one to three year period.<br />
The logging <strong>of</strong> <strong>the</strong> forest involves <strong>the</strong> construction <strong>of</strong> logging roads with bulldozers and graders.<br />
Log extraction from <strong>the</strong> forest is done by wheeled skidders and crawler tractors. Pres<strong>en</strong>t logging<br />
activities focus on three species; Azobe (Lophira alata), 60% <strong>of</strong> <strong>the</strong> extracted volume), Tali<br />
(Erythrophleum ivor<strong>en</strong>se) and Padouk (Pterocarpus soyauxii). Only trees with diameters at<br />
breast height (dbh) z 80 cm and straight boles <strong>of</strong> at least six meters are considered worthwhile.<br />
The resulting average logging int<strong>en</strong>sity is low, i.e. 10 m repres<strong>en</strong>ting 0.7 trees, compared<br />
with regions like Malaysia where on average 15 trees per hectare are removed. The felling and<br />
extraction <strong>of</strong> <strong>the</strong> logs from <strong>the</strong> stand are estimated to affect less than 15% <strong>of</strong> <strong>the</strong> surface (pers.<br />
comm. G.J.R. van Leersum, 1996).<br />
3 ha- l repres<strong>en</strong>ting 0.7 trees, compared<br />
with regions like Malaysia where on average 15 trees per hectare are removed. The felling and<br />
extraction <strong>of</strong> <strong>the</strong> logs from <strong>the</strong> stand are estimated to affect less than 15 % <strong>of</strong> <strong>the</strong> surface (pers.<br />
comm. G.J.R. van Leersum, 1996).<br />
Agriculture Agriculture is an an important land use in in <strong>the</strong> TCP research area. The traditional traditional shifting shifting cultivation<br />
system involves <strong>the</strong> clearing clearing and burning <strong>of</strong> primary and old secondary forest just before <strong>the</strong><br />
rainy season and <strong>the</strong> planting <strong>of</strong> cucumber, maize, cassava, cassava, coco-yam and plantain. With<br />
decreasing soil fertility, <strong>the</strong> t<strong>en</strong>ding and harvesting <strong>of</strong> a field gradually stops and <strong>the</strong> land is left<br />
fallow after a maximum <strong>of</strong> five years. The former agricultural fields are th<strong>en</strong> colonized by a<br />
forest vegetation. The biomass accumulation <strong>of</strong> <strong>of</strong> <strong>the</strong> secondary vegetation restores soil fertility.<br />
The traditional shifting shifting cultivation cultivation cycle is gradually being transformed by <strong>the</strong> introduction <strong>of</strong><br />
24
<strong>the</strong> chain saw, <strong>the</strong> limited amount <strong>of</strong> available labour and <strong>the</strong> scarcity <strong>of</strong> new land within reach<br />
<strong>of</strong> <strong>the</strong> village. More and more farmers are clearing young fallows for agricultural fields. They<br />
plant groundnut and cucumber in association with coco-yam, cassava and maize. The total<br />
surface <strong>of</strong> this rotational fallow system is less than t<strong>en</strong> hectares per farmer (pers. comm., M.<br />
Yemefack, 1996).<br />
NTFPs are a major source <strong>of</strong> food, construction materials, agricultural and household ut<strong>en</strong>sils,<br />
medicines and cash for <strong>the</strong> local population <strong>of</strong> Southwest Cameroon. The ga<strong>the</strong>ring <strong>of</strong>NTFPs is<br />
for <strong>the</strong> Bantu population supplem<strong>en</strong>tary to agriculture. For Bakola it is <strong>the</strong> mainstay. <strong>Survey</strong>s on<br />
NTFP collection have be<strong>en</strong> carried out in <strong>the</strong> neighbouring Campo-Ma'an area and in <strong>the</strong> TCP<br />
research area. Some 500 plant species were recorded in <strong>the</strong> TCP area alone that provided a total<br />
<strong>of</strong> nearly 1200 differ<strong>en</strong>t uses. The trade in NTFPs is an important source <strong>of</strong> income for <strong>the</strong> local<br />
population. The most traded NTFPs in <strong>the</strong> TCP area are for <strong>the</strong> Bantu population: oil palm (Elaeis<br />
guine<strong>en</strong>sis), bush mango (Irvingia gabon<strong>en</strong>sis) and <strong>the</strong> almond-like 'Njansang' (Ricinod<strong>en</strong>dron<br />
heudelotti). The Bakola collect and trade <strong>the</strong> fruits <strong>of</strong> <strong>the</strong> liana (Strophanthus gratus), honey and<br />
several oil containing nuts (e.g. Panda oleosa and Poga oleosa) (Dounias, 1993; pers. comm.<br />
J.F.W. van Dijk, 1996).<br />
Next to subsist<strong>en</strong>ce agriculture, cacao is cultivated for cash rev<strong>en</strong>ues by mainly Bantu farmers and<br />
small cacao plantations are found throughout <strong>the</strong> area. In g<strong>en</strong>eral <strong>the</strong>se plantations are not well<br />
maintained due to continuing low world market prices. The devaluation <strong>of</strong> <strong>the</strong> Franc CFA in 1994<br />
was an inc<strong>en</strong>tive for <strong>the</strong> production but still more than 50% <strong>of</strong> <strong>the</strong> cacao plantations remain<br />
abandoned. Rec<strong>en</strong>tly, industrial size oil palm, pineapple and banana plantations have be<strong>en</strong> created<br />
in <strong>the</strong> TCP area. Villagers who work and live in surrounding towns, appear to be <strong>the</strong> initiators <strong>of</strong><br />
this developm<strong>en</strong>t.<br />
25
3. METHODOLOGY<br />
3.1 LANDSCAPE ECOLOGICAL APPROACH<br />
The Trop<strong>en</strong>bos-Cameroon Programme aims at <strong>the</strong> developm<strong>en</strong>t <strong>of</strong> sustainable forms <strong>of</strong> land use<br />
in Southwest Cameroon. The specific objective <strong>of</strong> <strong>the</strong> first phase <strong>of</strong> <strong>the</strong> Lul project is to provide<br />
base line information on <strong>the</strong> biotic and abiotic <strong>en</strong>vironm<strong>en</strong>t <strong>of</strong> <strong>the</strong> TCP area. This information<br />
will be used for land evaluation and planning procedures and for more detailed ecological<br />
research in <strong>the</strong> area. Based on <strong>the</strong> size <strong>of</strong> <strong>the</strong> area and <strong>the</strong> need for detail for land evaluation, a<br />
landscape ecological survey at scale 1: 100,000 (reconnaissance scale) was carried out.<br />
Zonneveld (1995; after Schroevers, 1982) defines landscapes as 'a complex <strong>of</strong> relationships<br />
systems, toge<strong>the</strong>r forming ( ... ) a recognizable part <strong>of</strong> <strong>the</strong> earth's surface, which is formed and<br />
maintained by <strong>the</strong> mutual action <strong>of</strong> abiotic and biotic forces as well as human action'. The<br />
landscape can thus be se<strong>en</strong>, as is done in <strong>the</strong> pres<strong>en</strong>t study, as a fully integrated <strong>en</strong>tity that can<br />
and should be studied as a whole (e.g. Breimer et al., 1986; Hommel, 1987; Kiichler and<br />
Zonneveld, 1988; Zonneveld, 1995).<br />
Trop<strong>en</strong>bos has developed a Common Methodology for Land Inv<strong>en</strong>tory and Land Evaluation to<br />
contribute to a systematic and interdisciplinary research approach and subsequ<strong>en</strong>tly sound land<br />
use planning (Touber et al., 1989). This methodology focuses on <strong>the</strong> integrated description <strong>of</strong><br />
<strong>the</strong> <strong>en</strong>vironm<strong>en</strong>t and was used for <strong>the</strong> land unit surveys conducted in <strong>the</strong> Trop<strong>en</strong>bos sites in Cote<br />
d'Ivoire (de Rouw et al., 1990; de Rouw, 1991) and Colombia (Duiv<strong>en</strong>voord<strong>en</strong> and Lips, 1993;<br />
1995). The holistic nature <strong>of</strong> <strong>the</strong> landscape approach requires a multidisciplinary team <strong>of</strong><br />
surveyors.<br />
An almost indisp<strong>en</strong>sable tool in all landscape ori<strong>en</strong>ted studies is <strong>the</strong> use <strong>of</strong> remote s<strong>en</strong>sing<br />
materials. Dep<strong>en</strong>ding on <strong>the</strong> scale <strong>of</strong> <strong>the</strong> study and <strong>the</strong> objects to be mapped, satellite images and<br />
aerial photographs can be used. For <strong>the</strong> pres<strong>en</strong>t reconnaissance survey black & white aerial<br />
photographs have be<strong>en</strong> used. These images reveal <strong>the</strong> id<strong>en</strong>tity <strong>of</strong> <strong>the</strong> landscape and <strong>the</strong>ir<br />
systematic interpretation <strong>en</strong>ables <strong>the</strong> delineation <strong>of</strong> <strong>the</strong> differ<strong>en</strong>t land units. A land unit is 'a tract<br />
<strong>of</strong> land that is ecologically relatively homog<strong>en</strong>eous at <strong>the</strong> scale level concerned' (Zonneveld, (Zonneveld,<br />
1995). Aerial photo interpretation interpretation provides a basis for stratified sampling in <strong>the</strong> field.<br />
The aim <strong>of</strong> <strong>the</strong> fieldwork is to collect accurate and reliable materials to describe <strong>the</strong> photo<br />
interpretation units. In addition, <strong>the</strong> relevance <strong>of</strong> <strong>the</strong> boundaries <strong>of</strong> <strong>the</strong> photo interpretation units<br />
is studied. <strong>Ecological</strong> relevant data on soil, vegetation, geomorphology and land use, as well as<br />
geological, hydrological, zoological and o<strong>the</strong>r appropriate land attribute information are<br />
collected in selected sample sites. The land attributes are classified and a leg<strong>en</strong>d is compiled.<br />
The resulting landscape ecological map is an important tool for land evaluation. In <strong>the</strong> following<br />
sections, <strong>the</strong> methodological aspects <strong>of</strong> <strong>the</strong> pres<strong>en</strong>t survey are treated in more detail.<br />
3.2 AERIAL PHOTO INTERPRETATION<br />
Topographical base maps at scale 1 :50,000 were supplied by <strong>the</strong> CENADEFOR (1987) and are<br />
in fact <strong>en</strong>largem<strong>en</strong>ts <strong>of</strong> <strong>the</strong> 1 :200,000 topographic maps <strong>of</strong> <strong>the</strong> Institute Geographie Nationale<br />
(C6N, 1976). The sheets Edea NA-32-XX<strong>II</strong>I 1 lb, b, 2a and 2b and Nyabessan NA-32-XV<strong>II</strong> 3d, 4c<br />
27
and 4d were joint to make a single topographic map <strong>of</strong> <strong>the</strong> TCP area. The topographic map was<br />
updated as for <strong>the</strong> location <strong>of</strong> logging roads with <strong>the</strong> aid <strong>of</strong> a Global Positioning System (GPS).<br />
Black & white aerial photographs photographs <strong>of</strong> <strong>the</strong> TCP area were were tak<strong>en</strong> in 1963-66 1963-66 at a scale scale <strong>of</strong> 1 :50,000<br />
and in 1983-85 at a a scale <strong>of</strong> <strong>of</strong> 1 :20,000. The The 1963-66 series has insuffici<strong>en</strong>t contrast to to allow allow for<br />
stereoscopic vision. The much much better better quality photographs <strong>of</strong> <strong>the</strong> 1983-85 series have <strong>the</strong>refore<br />
be<strong>en</strong> used for photo interpretation in <strong>the</strong> pres<strong>en</strong>t survey. A list <strong>of</strong> <strong>the</strong> photographs is pres<strong>en</strong>ted<br />
in Annex Annex Ill. Ill.<br />
The interpretation interpretation <strong>of</strong> <strong>the</strong> aerial photographs resulted in <strong>the</strong> drafting <strong>of</strong> preliminary preliminary maps on<br />
landforms and vegetation at a scale 1 :50,000 (Touber, 1993a). The maps have have hierarchical<br />
leg<strong>en</strong>ds and discern a total total <strong>of</strong> 49 and 25 leg<strong>en</strong>ds units, respectively. A five week mission to <strong>the</strong><br />
TCP TCP research area was carried carried out out in 1993 and sites were selected for <strong>the</strong> effici<strong>en</strong>t sampling <strong>of</strong><br />
<strong>the</strong> most important land land units in <strong>the</strong> area (Touber, 1993b).<br />
3.3 FIELDWORK<br />
3.3.1 G<strong>en</strong>eral<br />
Observation sites were selected on <strong>the</strong> basis <strong>of</strong> <strong>the</strong> photo interpretation maps. Fieldwork<br />
involved <strong>the</strong> description <strong>of</strong> <strong>the</strong> attributes <strong>of</strong> <strong>the</strong> units discerned by photo-interpretation.<br />
Fieldwork was not merely a check check to verify verify <strong>the</strong> photo interpretation as it largely largely <strong>en</strong>tailed <strong>the</strong><br />
collection <strong>of</strong> new information.<br />
The land units sampled were considered <strong>the</strong> most important and widespread in <strong>the</strong> TCP area.<br />
The actual sample sites were selected on <strong>the</strong> basis <strong>of</strong> repres<strong>en</strong>tativ<strong>en</strong>ess repres<strong>en</strong>tativ<strong>en</strong>ess and accessibility.<br />
accessibility.<br />
Transects, or transverses, <strong>of</strong> one to two kilometres with a g<strong>en</strong>eral ori<strong>en</strong>tation perp<strong>en</strong>dicular to<br />
<strong>the</strong> contour lines, have have be<strong>en</strong> be<strong>en</strong> laid out. These transects provided access access to <strong>the</strong> land units units to to be be<br />
described and <strong>en</strong>abled <strong>the</strong> detection <strong>of</strong> possible cat<strong>en</strong>as or toposequ<strong>en</strong>tial processes. Within <strong>the</strong><br />
transect three to sev<strong>en</strong> observation points were selected for detailed description. The locations<br />
<strong>of</strong> <strong>the</strong> <strong>the</strong> observation observation points were determined by both <strong>the</strong> soil surveyor and <strong>the</strong> vegetation<br />
specialist. At each sampled locality, landform, soil and vegetation characteristics characteristics were<br />
described. In Fig. 3.1 <strong>the</strong> <strong>the</strong> distribution distribution <strong>of</strong> observation points in <strong>the</strong> TCP research research area is is giv<strong>en</strong>.<br />
During <strong>the</strong> field work <strong>the</strong> survey team consisted <strong>of</strong> <strong>of</strong> a soil surveyor, a vegetation surveyor, a field<br />
botanist (part-time), a local tree spotter and a local local soil survey assistant. The The transects were were laid laid<br />
out by a a 'compass man' and two line line cutters recruited from <strong>the</strong> nearest village. The distance distance<br />
along <strong>the</strong> <strong>the</strong> transects was measured measured with with a 'Top<strong>of</strong>yl' and each hundred hundred meter was (temporarily)<br />
marked with with a pole. The survey team covered approximately one kilometre per day day for normal<br />
sampling procedures. One or or two days extra were needed to dig and describe soil pits. pits.<br />
All transects and observation points have geographical coordinates and can be retraced on <strong>the</strong><br />
base map and <strong>the</strong> aerial photographs. Photo interpretation and fieldwork were not strictly<br />
separated in time; efforts have be<strong>en</strong> made to study <strong>the</strong> aerial photographs after each period <strong>of</strong><br />
fieldwork and to adjust <strong>the</strong> preliminary leg<strong>en</strong>ds and maps to <strong>the</strong> insights gained.<br />
The sampling procedures for landform, soil and vegetation aspects are discussed in in <strong>the</strong> sections<br />
3.3.2 and 3.3.3.<br />
28
The described land and soil related attributes are based on Touber et al. (1989), FAO (1990) and<br />
Touber et et al. (1993), and include: altitude, slope l<strong>en</strong>gth, slope steepness, slope form, exposition,<br />
landform, stone and rock coverage, erosion and stability characteristics, drainage drainage characteristics,<br />
groundwater groundwater level, biological activity and, humus form. Soil characteristics, described per horizon,<br />
are: colour, mottling, texture, structure, consist<strong>en</strong>cy, cutans, rooting characteristics and pores.<br />
Additionally, schematic sketches <strong>of</strong> <strong>the</strong> <strong>the</strong> transects were made, showing <strong>the</strong> variation in slope<br />
perc<strong>en</strong>tage, slope direction, slope l<strong>en</strong>gth, and exposition within within each each land unit.<br />
At least three auger hole observations per per transect were made. The auger holes were made with a<br />
standard standard type Edelman auger and and range in depth from 1.2 to 2.0 m. A total <strong>of</strong> <strong>of</strong> 207 soil and and landform<br />
observations were made. In Fig. Fig. 3.1 <strong>the</strong> distribution <strong>of</strong> observation points in <strong>the</strong> TCP area is<br />
pres<strong>en</strong>ted.<br />
After a first survey <strong>of</strong> <strong>the</strong> transects, about 60 sites repres<strong>en</strong>ting <strong>the</strong> differ<strong>en</strong>t differ<strong>en</strong>t landforms and and soil<br />
types <strong>of</strong> <strong>the</strong> TCP area were selected, soil pits were dug and soil characteristics were described in<br />
more detail. All soil pits have a minimum depth <strong>of</strong> 1.50 m. Samples <strong>of</strong> horizons were collected for<br />
chemical and physical analysis.<br />
Soil samples were chemically and physically analyzed at <strong>the</strong> IRA soil laboratory in Ekona.<br />
Duplicates <strong>of</strong> some 40 samples were analyzed as control at ISRIC, Wag<strong>en</strong>ing<strong>en</strong>. Chemical soil<br />
properties properties determined are organic carbon, total nitrog<strong>en</strong>, available and total phosphorous, pH H H20 20<br />
and KCI, exchangeable exchangeable bases (Na, K, Mg and Ca), Ca), aluminum aluminum and hydrog<strong>en</strong>, and cation exchange<br />
capacity capacity (CEC). Physical Physical parameters determined are are texture, water ret<strong>en</strong>tion characteristics (pF)<br />
and bulk d<strong>en</strong>sity. Additionally, <strong>the</strong> clay mineralogy <strong>of</strong> <strong>of</strong> some tw<strong>en</strong>ty-five samples were analyzed<br />
by ISRIC. The methods used for chemical and physical physical analyses analyses are described in in Annex IV.<br />
All field data concerning <strong>the</strong> site and soil characteristics <strong>of</strong> <strong>of</strong> <strong>the</strong> augerings augerings and and soil soil pr<strong>of</strong>ile<br />
descriptions were compiled compiled in in <strong>the</strong> <strong>the</strong> TROFOLIN Database Database (Touber et al., 1993). Data <strong>of</strong> chemical<br />
and physical analysis are stored stored in QUATTRO QUATTRO PRO.<br />
3.3.3 Vegetation<br />
The distribution <strong>of</strong> plant species in tropical forests is not random but reflects <strong>en</strong>vironm<strong>en</strong>tal<br />
conditions (Whitmore, 1984 and Zonneveld, 1995). Species which can successfully compete with<br />
one ano<strong>the</strong>r ano<strong>the</strong>r within <strong>the</strong> limits <strong>of</strong> a a particular combination <strong>of</strong> <strong>of</strong> <strong>en</strong>vironm<strong>en</strong>tal features can be be<br />
considered as a plant community. The mosaic <strong>of</strong> plant communities forms <strong>the</strong> vegetation in an area<br />
(Kuchler and Zonneveld, 1988). Moreover, <strong>the</strong> pattern <strong>of</strong> <strong>of</strong> vegetation vegetation types, defined defined as plantcommunities,<br />
may be used to assess <strong>the</strong> distribution patterns <strong>of</strong> distinct plant species.<br />
In <strong>the</strong> pres<strong>en</strong>t survey <strong>the</strong> vegetation was described on <strong>the</strong> basis <strong>of</strong> its structure and floristic<br />
composition, in <strong>the</strong> s<strong>en</strong>se <strong>of</strong> <strong>the</strong> <strong>the</strong> Fr<strong>en</strong>ch-Swiss school (phytosociological (phytosociological approach; approach; Braun Braun<br />
Blanquet, 1964). The method implies a classification <strong>of</strong> vegetation vegetation types by tabular tabular comparison<br />
<strong>of</strong> plot plot data, which leads leads to to <strong>the</strong> id<strong>en</strong>tification id<strong>en</strong>tification <strong>of</strong> communities, characterized by phytosociological<br />
groups (Touber et at., 1989).<br />
The localities described in <strong>the</strong> vegetation survey lie within <strong>the</strong> most common and widespread widespread photo<br />
interpretation units in <strong>the</strong> TCP research area (see 3.3.1). The stratification <strong>of</strong> sample points is based<br />
on <strong>the</strong> hypo<strong>the</strong>sis that altitude (Fig. 2.1) and disturbance disturbance (both anthropog<strong>en</strong>ic and and natural) cause<br />
most <strong>of</strong> <strong>the</strong> variation in <strong>the</strong> vegetation in <strong>the</strong> TCP research area. The observation points are are<br />
<strong>the</strong>refore ev<strong>en</strong>ly spread along <strong>the</strong>se two <strong>en</strong>vironm<strong>en</strong>tal gradi<strong>en</strong>ts gradi<strong>en</strong>ts (Table 3.1). Additionally, Additionally, in in<br />
relatively relatively undisturbed forest vegetation efforts have have be<strong>en</strong> be<strong>en</strong> made to to describe describe <strong>the</strong> <strong>the</strong> vegetation vegetation along along<br />
<strong>the</strong> toposequ<strong>en</strong>ce, comparable to <strong>the</strong> study <strong>of</strong> cat<strong>en</strong>a's in <strong>the</strong> soil survey.<br />
30
Next to to <strong>the</strong> detailed description <strong>of</strong> <strong>the</strong> sample points, <strong>the</strong> vegetation structure and land use along<br />
<strong>the</strong> transects was indicated on drawings. These drawings give insight in <strong>the</strong> mosaic <strong>of</strong> <strong>the</strong><br />
vegetation in <strong>the</strong> differ<strong>en</strong>t mapping units. In <strong>the</strong> second phase <strong>of</strong> <strong>the</strong> Lul project, will study <strong>the</strong>se<br />
mosaics are studied in more detail. Also some 20 incomplete or so-called 'quick releves' were<br />
described. These incomplete descriptions do not support <strong>the</strong> classification <strong>of</strong> <strong>the</strong> vegetation, but<br />
help to investigate <strong>the</strong> relations betwe<strong>en</strong> vegetation and abiotic factors. Moreover, <strong>the</strong>y are <strong>of</strong><br />
cartographic importance.<br />
All vegetation data have be<strong>en</strong> be<strong>en</strong> stored in in TURBOVEG, a s<strong>of</strong>tware package package for input, processing and<br />
pres<strong>en</strong>tation <strong>of</strong>phytosociological data (H<strong>en</strong>nek<strong>en</strong>s, 1995). The output <strong>of</strong> this package is, in contrast<br />
to TROFOLIN (Touber et al., 1993), compatible with vegetation classification programmes like<br />
TWINSPAN (Hill, 1979a), SHAKE SHAKE (Tonger<strong>en</strong>, unpubl.), unpubl.), DECORANA (Hill, (Hill, 1979b) and<br />
CANOCO (ter Braak, 1988).<br />
3.4 CLASSIFICATION<br />
Based on <strong>the</strong> variation observed within <strong>the</strong> TCP research area, preliminary classifications were<br />
drafted for landforms, soils and vegetation. To describe <strong>the</strong> landscape as a complex <strong>of</strong> <strong>the</strong>se<br />
attributes, <strong>the</strong> relations betwe<strong>en</strong> landforms, soils and vegetation types were studied by means <strong>of</strong><br />
cross-tables. cross-tables. The aim <strong>of</strong> <strong>of</strong> this exercise exercise was to trace trace <strong>the</strong> <strong>the</strong> parameters <strong>of</strong> <strong>the</strong> <strong>the</strong> abiotic <strong>en</strong>vironm<strong>en</strong>t <strong>en</strong>vironm<strong>en</strong>t which<br />
may best best explain <strong>the</strong> <strong>the</strong> variation variation in vegetation types. Based on on <strong>the</strong>se analysis, <strong>the</strong> landforms, soils<br />
and vegetation classifications classifications were slightly modified to attain an optimal 'ecological' 'ecological' fit.<br />
The classification classification <strong>of</strong> landforms is based on differ<strong>en</strong>ces in relief characteristics, i.e. slope l<strong>en</strong>gth,<br />
slope steepness, relief int<strong>en</strong>sity, and <strong>the</strong> number <strong>of</strong> interfluves. These characteristics are important<br />
in <strong>the</strong> light <strong>of</strong> land utilization. utilization.<br />
The classification <strong>of</strong> soils in <strong>the</strong> TCP research area is primarily based on soil drainage and soil<br />
texture. Soil depth and stoniness are o<strong>the</strong>r differ<strong>en</strong>tiating criteria but could not be used at this scale.<br />
Soil drainage and texture are found to have a correlation with vegetation in <strong>the</strong> TCP research area.<br />
As soil texture and soil drainage are indicators for moisture availability, <strong>the</strong>y are two <strong>of</strong> <strong>the</strong><br />
functional soil parameters for land evaluation as well.<br />
The classification <strong>of</strong> <strong>the</strong> vegetation <strong>of</strong> <strong>the</strong> area was done by means <strong>of</strong> 'tabular comparison' <strong>of</strong> <strong>the</strong><br />
releve data using <strong>the</strong> computer programme TWINSP AN (Hill, 1979a). The programme performs<br />
a multi-variate analysis <strong>of</strong> vegetation data and produces a hierarchical classification <strong>of</strong> both sample<br />
points and species. Manual refinem<strong>en</strong>t <strong>of</strong> this this classification included <strong>the</strong> reallotm<strong>en</strong>t <strong>of</strong> a limited<br />
number <strong>of</strong> borderline releves. Also some 11 releves were excluded from analysis because <strong>the</strong>y<br />
proved to repres<strong>en</strong>t ei<strong>the</strong>r intermediate situations on <strong>the</strong> highest level <strong>of</strong> classification, or<br />
repres<strong>en</strong>ted ecologically ecologically aberrant aberrant situations situations that were not not considered relevant to <strong>the</strong> <strong>the</strong> reconnaissance<br />
survey.<br />
The cover values <strong>of</strong> <strong>of</strong> <strong>the</strong> three structural layers, i.e. i.e. tree, shrub and and herb layer, layer, have be<strong>en</strong> combined combined<br />
into one value for each species. species. Four coverage classes were used, 0-5%, > 5-25%, > 25-50% and<br />
> > 50-100% cover, regardless <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> abundance <strong>of</strong> <strong>the</strong> species. For classification <strong>of</strong> vegetation on<br />
a reconnaissance scale, this is considered suffici<strong>en</strong>tly detailed.<br />
The classification by TWINSPAN is primarily based on <strong>the</strong> floristic composition <strong>of</strong> <strong>the</strong> sample<br />
plots. Next, a a synecological interpretation <strong>of</strong> <strong>the</strong> vegetation types discerned has be<strong>en</strong> carried out out<br />
on <strong>the</strong> basis basis <strong>of</strong> <strong>the</strong> <strong>en</strong>vironm<strong>en</strong>tal data collected at <strong>the</strong> differ<strong>en</strong>t plot sites.<br />
32
3.5 LEGEND AND MAP COMPILATION<br />
The final leg<strong>en</strong>d <strong>of</strong><strong>the</strong> landscape ecological map is based on <strong>the</strong> classification systems for <strong>the</strong><br />
individual attributes (landform, soil and vegetation), <strong>the</strong> study <strong>of</strong> correlations betwe<strong>en</strong> <strong>the</strong>se<br />
attributes and <strong>the</strong> annotated preliminary photo interpretation maps (Hommel, 1987; Kiichler and<br />
Zonneveld, 1988).<br />
The landscape ecological map (l: 100,000) is thus based on 256 landform and soil observations<br />
and 125 vegetation releves, and covers a total surface <strong>of</strong> 167,350 ha. Consequ<strong>en</strong>tly, <strong>the</strong><br />
observation d<strong>en</strong>sity for landform and soil attributes is one per 650 ha and one per 1150 ha for<br />
<strong>the</strong> vegetation attributes. These observation d<strong>en</strong>sities are <strong>the</strong>oretically just suffici<strong>en</strong>t (Landon,<br />
1991).<br />
The repres<strong>en</strong>tation <strong>of</strong> <strong>the</strong> id<strong>en</strong>tified vegetation, soil and landform types on a map map dep<strong>en</strong>ds<br />
largely on mapping scale. In <strong>the</strong> pres<strong>en</strong>t reconnaissance survey (scale 1: 100,000) most <strong>of</strong> <strong>the</strong><br />
units <strong>of</strong> <strong>the</strong> pres<strong>en</strong>t landscape ecological map contain mosaics <strong>of</strong> <strong>of</strong> soil and vegetation types.<br />
Map compilation has be<strong>en</strong> facilitated by <strong>the</strong> GIS package ArcInfo Arclnfo (ESRI, 1990; 1994). 1994). Digitized<br />
topographic topographic base base maps have be<strong>en</strong> made compatible with <strong>the</strong> land land attribute classification systems,<br />
<strong>en</strong>abling spatial analysis and <strong>the</strong> compilation <strong>of</strong> land attribute and evaluation maps (Bakkum,<br />
1996).<br />
33
4. LANDFORMS<br />
4.1 LITERATURE REVIEW<br />
The geomorphology <strong>of</strong> Southwest Cameroon is described by Martin and Segal<strong>en</strong> (1966) and by<br />
Franqueville (1973) at a scale <strong>of</strong> 1:1,000,000. The western part <strong>of</strong> <strong>the</strong> TCP area belongs to <strong>the</strong><br />
coastal lowland <strong>of</strong> late Tertiary-Quaternary age, whereas <strong>the</strong> eastern part belongs to <strong>the</strong> interior<br />
plateau <strong>of</strong> Eoc<strong>en</strong>e age. At <strong>the</strong> boundary <strong>of</strong> <strong>the</strong>se two zones a transitional complex is found (Segal<strong>en</strong>,<br />
1967). At this transition differ<strong>en</strong>t planation levels are pres<strong>en</strong>t. The planation levels at 200 to<br />
300 m and 600 to 800 m correspond with <strong>the</strong> erosion surfaces Africa <strong>II</strong> and I (Martin and Segal<strong>en</strong>,<br />
1966; Franqueville, 1973). The two erosion surfaces have a well pronounced relief. They are<br />
characterized by hills and dissected uplands with numerous small streams. The slopes <strong>of</strong> <strong>the</strong> hills<br />
and uplands have convex upper parts and concave lower parts. Laterite banks are <strong>of</strong> minor<br />
importance and <strong>the</strong> tropical clay soils are g<strong>en</strong>erally deep.<br />
We have subdivided <strong>the</strong> area into four altitude classes which party coincide with <strong>the</strong> m<strong>en</strong>tioned<br />
erosion surfaces. The altitude classes are < 350 m, 350-500 m, 500-700 m and> 700 m.<br />
Important processes leading to <strong>the</strong> formation <strong>of</strong> today's landforms have be<strong>en</strong> tectonic movem<strong>en</strong>ts<br />
<strong>of</strong> parts <strong>of</strong> <strong>the</strong> Precambrian shield, e.g. block faulting along NE - SW lines, climatic changes and<br />
erosion processes related to rapid changes <strong>of</strong> <strong>the</strong> erosion basis. These processes resulted in<br />
differ<strong>en</strong>t planation levels or erosion surfaces (Martin and Segal<strong>en</strong>, 1966; Buckle, 1978; Embleton<br />
and Thornes, 1979). The physiognomy <strong>of</strong> <strong>the</strong> landscape is still being 'reformed'. The most<br />
important process is water erosion resulting in <strong>the</strong> dissection <strong>of</strong> <strong>the</strong> area. The int<strong>en</strong>sity <strong>of</strong> this<br />
dissection is determined by <strong>the</strong> relative differ<strong>en</strong>ces in erodibility <strong>of</strong> both soil cover and underlying<br />
rock, and by <strong>the</strong> amount <strong>of</strong> rainfall. Differ<strong>en</strong>ces in erodibility <strong>of</strong> <strong>the</strong> rock are caused by differ<strong>en</strong>ces<br />
in d<strong>en</strong>sity <strong>of</strong> fractures and/or its mineral composition.<br />
Table 4.1 Relief characteristics <strong>of</strong> <strong>the</strong> differ<strong>en</strong>t landforms<br />
Landform units Slope l<strong>en</strong>gth Slope (%) Relief No. <strong>of</strong> Altitude Surface area<br />
(m) int<strong>en</strong>sity (m) interfluves<br />
perkm perkm2<br />
range (m) (km2)<br />
Dissected erosional<br />
plains (pd)<br />
50-200 5-15 20- 30 3-4 40-280 110<br />
Uplands (ul) 100-200 10-20 10- 40 3-4 120-700 480<br />
Uplands (u2) 150-300 10-30 30- 80 2-3 120-700 690<br />
Isolated hills (hi) 250-500 > 30 120-300 200-900 116<br />
Complex <strong>of</strong> hills (h2)<br />
Mountains (m)<br />
200-350 20-40 80-200 350-700 139<br />
- outside slopes > 400 > 30 >250 >500 100<br />
- inside slopes 250-400 30-60 120-250<br />
Valley bottoms (v) 0-2 30 120-300 200-900 116<br />
Complex <strong>of</strong> hills (h2)<br />
Mountains (m)<br />
200-350 20-40 80-200 350-700 139<br />
- outside slopes > 400 > 30 >250 >500 100<br />
- inside slopes 250-400 30-60 120-250<br />
Valley bottoms (v) 0-2
The moderately dissected uplands with rolling relief have slopes <strong>of</strong> 100 to 200 meters long;<br />
<strong>the</strong>se slopes are moderately steep (10-20%). The number <strong>of</strong> interfluves per kilometre ranges<br />
from three to four and <strong>the</strong> relief int<strong>en</strong>sities are betwe<strong>en</strong> 10 and 40 meters. This landform covers<br />
large surfaces in <strong>the</strong> c<strong>en</strong>tral and nor<strong>the</strong>rn parts <strong>of</strong> <strong>the</strong> TCP area, has altitudes betwe<strong>en</strong> 350 and<br />
500 m asl, and has a g<strong>en</strong>eral NE-SW direction. It has gradual boundaries with <strong>the</strong> dissected<br />
erosional plains and <strong>the</strong> strongly dissected uplands with hilly relief. Sharp transitions are found<br />
with <strong>the</strong> hills and <strong>the</strong> mountains. The 'rolling uplands' cover about 27% <strong>of</strong> <strong>the</strong> TCP research<br />
area.<br />
The strongly dissected uplands with hilly relief have two to three interfluves per kilometre,<br />
slopes <strong>of</strong> 150-300 meter long which are moderately steep (10-30%), and relief int<strong>en</strong>sities <strong>of</strong>30-<br />
80 meter. The overall relief is hilly. The 'hilly uplands' with an ext<strong>en</strong>t <strong>of</strong> 39% <strong>of</strong> <strong>the</strong> survey area<br />
are <strong>the</strong> most predominant landform in <strong>the</strong> TCP research area. They are confined to <strong>the</strong> 120-700<br />
meter altitude range. They have relatively sharp boundaries with <strong>the</strong> mountains, hills and<br />
complexes <strong>of</strong> hills, and gradual boundaries with <strong>the</strong> rolling uplands.<br />
4.2.3 Hills (hI and h2)<br />
Hills are natural elevations <strong>of</strong> <strong>the</strong> earth's surface. Hills occupy smaller areas, are lower and/or<br />
have lower relief int<strong>en</strong>sities than <strong>the</strong> mountains. Two types <strong>of</strong> hills are discerned in <strong>the</strong> pres<strong>en</strong>t<br />
reconnaissance survey: isolated hills (hI) and complexes <strong>of</strong> hills (h2). Both landforms are<br />
characterized by erosion, particularly sheet erosion (creep) and rockfalls.<br />
The isolated hills are characterized by steep (> 30%) long slopes (250-500 m) and relief<br />
int<strong>en</strong>sities <strong>of</strong> 120-300 meters. Rock outcrops are common and <strong>the</strong>y are frequ<strong>en</strong>tly <strong>en</strong>countered<br />
at <strong>the</strong> convex upper slopes. The isolated hills are steep-sided, isolated, residual and circumd<strong>en</strong>udated<br />
like inselbergs. They are scattered throughout <strong>the</strong> TCP area and are a characteristic<br />
aspect <strong>of</strong> <strong>the</strong> landscape, especially in <strong>the</strong> uplands <strong>of</strong> <strong>the</strong> c<strong>en</strong>tral region. The isolated hills are<br />
conspicuously pres<strong>en</strong>t in <strong>the</strong> landscape, ev<strong>en</strong> though <strong>the</strong>y cover only 9% <strong>of</strong> <strong>the</strong> total TCP area.<br />
The landform h2 is a complex <strong>of</strong> moderately steep to steep (20-40%) hills which are strongly<br />
dissected. The slopes are relatively short (200-350 m) and <strong>the</strong> relief int<strong>en</strong>sities (80-200 m) are<br />
relatively low, wh<strong>en</strong> compared to <strong>the</strong> isolated hills and mountains. The complex <strong>of</strong> hills are<br />
characterized by a large variation in summit and valley valley bottom levels. levels. Complexes Complexes <strong>of</strong> hills are are<br />
mainly situated in <strong>the</strong> transition zone betwe<strong>en</strong> <strong>the</strong> uplands <strong>of</strong> <strong>the</strong> c<strong>en</strong>tral region and <strong>the</strong><br />
mountains in <strong>the</strong> eastern part <strong>of</strong> <strong>the</strong> TCP area. They have a g<strong>en</strong>eral NE-SW direction. Altitudes<br />
vary betwe<strong>en</strong> 500 and 700 m asl. They are abs<strong>en</strong>t in <strong>the</strong> northwest <strong>of</strong> <strong>the</strong> TCP research area. The<br />
complexes <strong>of</strong> hills cover a surface <strong>of</strong> about 130 km2, which is 9% <strong>of</strong> <strong>the</strong> TCP research area.<br />
4.2.4 Mountains (m)<br />
Mountains are complex dissected plateaus or massifs which are isolated and rising above <strong>the</strong><br />
surrounding landscape. This landform is characterized by an abrupt rise in altitude to a higher<br />
level. Sheet erosion (creep) and rockfalls also occur in this landform. The outside slopes <strong>of</strong> <strong>the</strong><br />
mountains blocks are very long (> 400 m), very steep (30 to over 60%) with a relief int<strong>en</strong>sity<br />
higher than 250 meters. The inside slopes are moderately long (250-400 m), steep (30-60%) and<br />
have a relief int<strong>en</strong>sity <strong>of</strong> 120-250 meters. Rock outcrops are common and mainly occur on <strong>the</strong><br />
convex upper slopes. The mountains are restricted to <strong>the</strong> eastern part <strong>of</strong> <strong>the</strong> TCP area with altitudes<br />
above 500 m asl where <strong>the</strong>y cover about 100 km2, i.e. some 7% <strong>of</strong> <strong>the</strong> TCP research area.<br />
37
4.2.5 Valley Bottoms (v)<br />
Valley bottoms are poorly to very poorly drained, nearly flat to flat depressions betwe<strong>en</strong><br />
interfluves. They occupy ext<strong>en</strong>sive areas within <strong>the</strong> uplands and dissected erosional plains. Their<br />
widths are mainly 50-150 meters and are thus in g<strong>en</strong>eral too small to be mapped separately at<br />
1: 100,000 scale. The slope perc<strong>en</strong>tages are betwe<strong>en</strong> 0 and 2%. Stagnation <strong>of</strong> water is also an<br />
important characteristic. Soils are developed in unconsolidated, unspecified, stratified alluvium,<br />
which rec<strong>en</strong>tly has be<strong>en</strong> deposited.<br />
The The valley bottoms are found predominantly in <strong>the</strong> sou<strong>the</strong>ast sou<strong>the</strong>ast <strong>of</strong> <strong>the</strong> TCP research and and in <strong>the</strong> <strong>the</strong><br />
western lowlands. Large valley bottoms, i.e. wider than than 250 m, are separately mapped in <strong>the</strong><br />
pres<strong>en</strong>t reconnaissance survey. These large valley bottoms cover approximately one perc<strong>en</strong>t <strong>of</strong> <strong>the</strong><br />
TCP research area. However, this does not reflect <strong>the</strong> importance <strong>of</strong> <strong>the</strong> landform as <strong>the</strong> majority<br />
<strong>of</strong> valley bottoms are part <strong>of</strong> <strong>the</strong> dissected erosional plains, and uplands.<br />
38
5. SOILS<br />
5.1 LITERATURE REVIEW<br />
The' Atlas du Cameroun' (1 :2,000,000) and <strong>the</strong> 'Carte Pedologique du Cameroun Ori<strong>en</strong>tal'<br />
(1: (1:1,000,000) 1 ,000,000) provide information on <strong>the</strong> soils in <strong>the</strong> TCP research area. The scales <strong>of</strong> <strong>the</strong>se soil<br />
maps differ greatly from this reconnaissance inv<strong>en</strong>tory (1: 100,000). These maps with <strong>the</strong>ir<br />
explanatory notes (Segal<strong>en</strong>, 1957; Martin and Segal<strong>en</strong>, 1966), toge<strong>the</strong>r with <strong>the</strong>' Atlas Regional,<br />
Sud-ouest I' by Franqueville (1973) give a good indication <strong>of</strong> <strong>the</strong> main soils <strong>of</strong> Southwest<br />
Cameroon. The three main soil types <strong>of</strong> Southwest Cameroon, according to <strong>the</strong> above m<strong>en</strong>tioned<br />
studies, are are' 'les les sols ferrallitiques jaunes sur roches acides (gneiss)', 'les sols ferrallitiques<br />
rouges sur roches acides' and 'les sols alluviaux' (see also section 2.6).<br />
According to <strong>the</strong>' Atlas du Sud Cameroon, scale 1 :500,000 (MINREST and ORSTOM, 1995),<br />
<strong>the</strong>'sols ferralitiques fortem<strong>en</strong>t desaturees typiques jaunes ou rajeuni jaunes cl ocres' and 'les<br />
sols peu evolues ou bruts' are found around <strong>the</strong> city <strong>of</strong> Ebolowa east <strong>of</strong> <strong>the</strong> TCP study area.<br />
South <strong>of</strong> <strong>the</strong> line Ebemvok and <strong>Akom</strong> 11, a detailed soil study <strong>of</strong> 65 hectares has be<strong>en</strong> carried<br />
out by Roubain who paid special att<strong>en</strong>tion to <strong>the</strong> g<strong>en</strong>esis <strong>of</strong> soils. He reports that well drained<br />
yellowish brown clay soils dominate on gneisses, whereas <strong>the</strong> reddish brown soils occur on<br />
basaltic rocks. Laterite banks are exceptional in this region (ORSTOM - Roubain, pers. comm.,<br />
1995).<br />
Soil studies in <strong>the</strong> Mbalmayo area, situated nor<strong>the</strong>ast <strong>of</strong> <strong>the</strong> TCP research area, were carried out<br />
on inv<strong>en</strong>tory scale by Yemefack and Moukam (1995) and on detailed scale by Ndjib (1987) and<br />
Ngeh et al. (1995). The soils in this area have be<strong>en</strong> developed on (mica)schists, gneisses and<br />
granites <strong>of</strong> Precambrian age. Yemefack and Moukam (1995) classify <strong>the</strong> dominating well<br />
drained yellowish brown clay soils as Xanthic Ferralsols (low cation exchange capacity, low<br />
base saturation) with or without textural differ<strong>en</strong>tiation.<br />
Ndjib (1987) differ<strong>en</strong>tiates <strong>the</strong> strongly wea<strong>the</strong>red soils on <strong>the</strong> basis <strong>of</strong> texture, coarse fragm<strong>en</strong>t<br />
cont<strong>en</strong>t and colour. He relates <strong>the</strong>se differ<strong>en</strong>ces to par<strong>en</strong>t material (soils on schists have more<br />
coarse fragm<strong>en</strong>ts than <strong>the</strong> ones on gneiss) and physiographic positions (developm<strong>en</strong>t <strong>of</strong> argic<br />
properties on top positions and mid-slopes).<br />
Bilong (1992) reports that around Akongo, which is also east <strong>of</strong> <strong>the</strong> TCP research area, well<br />
drained yellowish brown clay soils are formed on all kinds <strong>of</strong> par<strong>en</strong>t materials. He relates <strong>the</strong><br />
yellowish colour to goethite, an iron hydroxide. hydroxide. Goethite, which can be formed under a soil<br />
climate climate with with suffici<strong>en</strong>t moisture in <strong>the</strong> dry seasons, gives a yellowish brown colour to <strong>the</strong> soil<br />
(Bilong, 1992).<br />
According to Touber (1993b) <strong>the</strong> soils in <strong>the</strong> TCP research are remarkably uniform throughout<br />
<strong>the</strong> area. They are well to moderately well drained, very deep, yellowish brown clay loams to<br />
light clays. Variations in depth, internal drainage, texture and gravel cont<strong>en</strong>t occur. Some<br />
patches <strong>of</strong> redder soils may occur and an altoge<strong>the</strong>r differ<strong>en</strong>t soil type is found in <strong>the</strong> valleys.<br />
39
The pres<strong>en</strong>t study confirms that deep, moderately well to well drained yellowish brown brown tropical<br />
clay soils predominate in <strong>the</strong> TCP research area. These soils also described as 'les sols<br />
ferrallitiques jaunes sur les roches acides (gneiss)' are characterized by Martin and Segal<strong>en</strong> (1966)<br />
as follows:<br />
topsoil (3-10 cm): 15 to 20% clay, ± 3.5% organic matter (CIN = 15), CEC < 8 meqllOO g, base<br />
saturation betwe<strong>en</strong> 12 and 20% and pH < 4.5;<br />
subsoil (> 10 cm): 35-50% clay, low in organic matter « 3.5%), CEC betwe<strong>en</strong> 5 and 7 meq/l00<br />
g and base saturation < 10%.<br />
Vertical clay movem<strong>en</strong>t is described. The mineralogical composition <strong>of</strong> <strong>the</strong> clay is: 50-60%<br />
kaolinite, 35-45% goethite and < 10% gibbsite and <strong>the</strong> Si02/Al203 ratio is betwe<strong>en</strong> 1.1 and 1.6.<br />
5.2 SOIL TYPES AND CLASSIFICATION<br />
The soils in <strong>the</strong> <strong>Bipindi</strong> - Lolodorf - <strong>Akom</strong> <strong>II</strong> area have be<strong>en</strong> subdivided into four main soil types.<br />
This subdivision is based on soil drainage and texture in both topsoil and subsoil (table 5.1).<br />
Well drained, deep deep to very deep deep1, 1, yellowish brown to strong brown clay clay soils, classified according<br />
to FAO-Unesco (1990) as Xanthic Ferralsols, are dominant in <strong>the</strong> area. These well drained soils<br />
are fur<strong>the</strong>r subdivided according to <strong>the</strong> clay cont<strong>en</strong>t in topsoil and subsoil into:<br />
Nyangong soils which which are very clayey soils soils with no or only a a gradual increase in in clay cont<strong>en</strong>t<br />
with depth. The clay cont<strong>en</strong>ts cont<strong>en</strong>ts <strong>of</strong> <strong>of</strong><strong>the</strong> <strong>the</strong> subsoils range betwe<strong>en</strong> 50 and 80%.<br />
- Ebom soils which are clay soils with a gradual to strong differ<strong>en</strong>tiation in clay cont<strong>en</strong>t betwe<strong>en</strong><br />
topsoils and subsoils. subsoils. The clay clay cont<strong>en</strong>ts <strong>of</strong> <strong>the</strong> subsoils range betwe<strong>en</strong> 35 and 60%.<br />
The moderately well drained soils are:<br />
Ebimimbang soils which are moderately deep to very deep clay soils with sandy topsoils. The<br />
clay cont<strong>en</strong>ts <strong>of</strong> <strong>the</strong> subsoils range betwe<strong>en</strong> 20 and 45%.<br />
The poorly to very poorly drained soils are:<br />
- Valley Bottom soils soils which which are moderately deep to very very deep soils, locally stratified and with<br />
variable textures in topsoils and subsoils.<br />
The first three soil types are named after villages in <strong>the</strong> TCP area in which regions <strong>the</strong>se<br />
corresponding soil types dominate. The Valley Bottom soils are, as <strong>the</strong> name implies, restricted<br />
to <strong>the</strong> valleys and occur all over <strong>the</strong> area.<br />
Soil depth, soil stoniness stoniness and and <strong>the</strong> occurr<strong>en</strong>ce occurr<strong>en</strong>ce <strong>of</strong> plinthite in <strong>the</strong> subsoils subsoils are are o<strong>the</strong>r criteria for fur<strong>the</strong>r fur<strong>the</strong>r<br />
subdivision <strong>of</strong> <strong>the</strong> soils. During <strong>the</strong> pres<strong>en</strong>t reconnaissance survey it has, however, not be<strong>en</strong><br />
possible to find systematic relationships betwe<strong>en</strong> <strong>the</strong>se factors and positions in <strong>the</strong> landscape.<br />
Therefore, <strong>the</strong>se criteria have not be<strong>en</strong> used to fur<strong>the</strong>r subdivide <strong>the</strong> four main soil types m<strong>en</strong>tioned<br />
above.<br />
Soil depths classes are as follows: shallow 0-50 cm; moderately deep 50-100 cm; deep 100-150 cm cm and very very deep<br />
>150 >150 cm.<br />
40
Table 5.1 Soil types <strong>of</strong> <strong>the</strong> TCP research area and <strong>the</strong>ir diagnostic criteria<br />
Soil type<br />
Drainage<br />
Nyangong<br />
Well drained<br />
Ebom<br />
Well drained<br />
Ebimimbang Moderately well drained<br />
Valley Bottom Poorly to very poorly drained<br />
Topsoil Topsoil = 0-10 0-10 cm; cm; subsoil subsoil = 20-60 20-60 cm cm<br />
Texture<br />
(% clay topsoil)<br />
35-70%, very clayey<br />
20-50%, clayey<br />
0-25%, sandy<br />
variable<br />
Texture<br />
(% clay subsoil)<br />
50-80% 50-80%<br />
35-60%<br />
20-45%<br />
variable variable<br />
5.2.1 Nyangong soils<br />
The Nyangong soils are deep to very deep, well drained, yellowish brown to strong brown, clays<br />
with dark yellowish brown to dark brown clay topsoils. They are developed on fine grained,<br />
pyrox<strong>en</strong>e rich gneisses and granites, or o<strong>the</strong>r igneous rocks. Soil depth <strong>of</strong> <strong>the</strong> deep soils (100 -<br />
150cm) is limited by <strong>the</strong> occurr<strong>en</strong>ce <strong>of</strong> ferruginated gravel, stones, boulders or wea<strong>the</strong>ring<br />
bedrock. Nyangong soils are characterised by a high clay cont<strong>en</strong>t which can reach 80% in <strong>the</strong><br />
subsoils. The topsoils are none to slightly less clayey than <strong>the</strong> subsoils whereby <strong>the</strong> increase in<br />
clay cont<strong>en</strong>t with depth is gradual.<br />
The topsoils are 10 to 20 cm thick with <strong>the</strong> first 5 to 10 cm having <strong>the</strong> darkest colours. They<br />
have dark yellowish brown to dark brown colours and 40 to 70% clay. The subsoils have<br />
yellowish brown to strong brown colours and clay cont<strong>en</strong>ts <strong>of</strong> 50 to 80%. In places few reddish<br />
mottles and/or laterite gravel is found in <strong>the</strong> deeper subsoils.<br />
Locally on summits, upper slopes or very steep mountain slopes, moderately deep to very deep,<br />
gravelly and stony soils occur as inclusions within <strong>the</strong> Nyangong soils. These have clay cont<strong>en</strong>ts<br />
in <strong>the</strong> subsoils <strong>of</strong> 40 to 50% and are less deeply and less int<strong>en</strong>sively wea<strong>the</strong>red than <strong>the</strong> typical<br />
Nyangong soils. At <strong>the</strong> pres<strong>en</strong>t scale <strong>of</strong> <strong>the</strong> survey, <strong>the</strong>se soils could not be mapped separately.<br />
The Nyangong soils are characteristic for altitudes above 500 m asl and are <strong>the</strong>refore found in<br />
<strong>the</strong> mountains and hills in <strong>the</strong> eastern part <strong>of</strong> <strong>the</strong> TCP area. The complexes <strong>of</strong> hills and isolated<br />
hills at altitudes above 500 m are also mainly covered with <strong>the</strong> Nyangong soils. The soils <strong>of</strong> <strong>the</strong><br />
eastern uplands form complexes <strong>of</strong>Nyangong and Ebom soils.<br />
Full pr<strong>of</strong>ile descriptions with analytical data <strong>of</strong> <strong>the</strong> Nyangong soils are giv<strong>en</strong> in Annex IV.<br />
5.2.2 Ebom soils<br />
The Ebom soils are deep to very deep, well drained brownish yellow to strong brown, clays with<br />
yellowish brown to dark brown sandy loam to sandy clay topsoils. They are developed on<br />
gneisses and migmatites. Soil depth <strong>of</strong> <strong>the</strong> deep soils (100-150 cm) is limited by plinthite,<br />
laterite and/or quartz gravel or bedrock. A relationship betwe<strong>en</strong> <strong>the</strong> occurr<strong>en</strong>ce <strong>of</strong> plinthite or<br />
limited soil depth within 150 cm and topographical position, could not be detected and <strong>the</strong>refore<br />
not mapped at <strong>the</strong> scale on <strong>the</strong> survey. The Ebom soils are characterized by <strong>the</strong>ir clayey subsoils<br />
with less clayey topsoils whereby an increase in clay cont<strong>en</strong>t with depth <strong>of</strong> about 10% g<strong>en</strong>erally<br />
occurs within 20 to 25 cm <strong>of</strong> <strong>the</strong> surface.<br />
The topsoils are 10 to 20 cm thick, have yellowish brown to dark brown colours (with <strong>the</strong> first<br />
5 cm having <strong>the</strong> darkest colours), and have 20 to 40% clay (sandy loam to sandy clay). The<br />
subsoils g<strong>en</strong>erally have 40 to 50% clay with an observed range <strong>of</strong>35 to 60% and have brownish<br />
yellow to strong brown colours, with yellowish brown dominating. In a majority <strong>of</strong> <strong>the</strong> soils<br />
41
eddish mottles mottles occur, occur, starting starting betwe<strong>en</strong> betwe<strong>en</strong> 20 20 and and 50 cm depth. depth. Iron Iron concretions occur in in <strong>the</strong> deeper<br />
subsoils, starting betwe<strong>en</strong> betwe<strong>en</strong> 50 to 100 cm depth. depth.<br />
Locally on summits, steep upper slopes or very steep hill slopes, moderately deep to very deep,<br />
gravelly and stony soils occur as inclusions within <strong>the</strong> Ebom soils. These have clay cont<strong>en</strong>ts in<br />
<strong>the</strong> <strong>the</strong> subsoils subsoils <strong>of</strong> 40 40 to to 50% and and are are less less deeply deeply and and less less int<strong>en</strong>sively wea<strong>the</strong>red wea<strong>the</strong>red than than <strong>the</strong> <strong>the</strong> typical typical<br />
Ebom Ebom soils. soils. At <strong>the</strong> pres<strong>en</strong>t scale scale <strong>of</strong> <strong>the</strong> survey, <strong>the</strong>se soils could not be mapped separately.<br />
The Ebom soils are typically found in <strong>the</strong> uplands and isolated hills in <strong>the</strong> c<strong>en</strong>tral and nor<strong>the</strong>rn<br />
regions regions <strong>of</strong> <strong>the</strong> TCP TCP area area at at altitudes altitudes betwe<strong>en</strong> betwe<strong>en</strong> 350 and and 500 m asl. asl. Complexes Complexes <strong>of</strong> <strong>the</strong> Ebom Ebom with with<br />
Nyangong Nyangong soils are found in <strong>the</strong> uplands above 500 m.<br />
Full pr<strong>of</strong>ile descriptions with analytical data <strong>of</strong> <strong>the</strong> Ebom soils are giv<strong>en</strong> in Annex IV.<br />
5.2.3 Ehimimhang Ebimimbang soils<br />
The Ebimimbang soils are are moderately moderately deep to very deep, moderately moderately well well to well well drained, drained,<br />
yellowish yellowish brown brown sandy clay clay loams to sandy clays with sand to sandy loam topsoils and with<br />
gravelly subsoils. They are developed on coarse grained gneisses and migmatites. They are<br />
characterized characterized by by sandy sandy topsoils topsoils and and a a clay clay increase increase with with depth depth <strong>of</strong> 15 to 20% 20% which which g<strong>en</strong>erally<br />
occurs occurs within within 20 20 cm cm <strong>of</strong> <strong>the</strong> surface. The The depth depth <strong>of</strong> <strong>the</strong> moderately moderately deep deep soils (50-100 cm) cm) is is<br />
limited by wea<strong>the</strong>ring bedrock, plinthite or high conc<strong>en</strong>trations <strong>of</strong> gravel (both iron concretions<br />
or or quartz quartz gravel).<br />
The topsoils are 5 to 10 cm thick, with colours in <strong>the</strong> range <strong>of</strong> dark greyish brown to black and<br />
g<strong>en</strong>erally with about 20% clay clay but clay perc<strong>en</strong>tages perc<strong>en</strong>tages as as low as 9% occur as well. well. The subsurface<br />
horizons horizons are 5 to to 10 cm thick, have yellowish brown to dark brown colours and have clay<br />
perc<strong>en</strong>tages perc<strong>en</strong>tages <strong>of</strong> 16 to 25 %, but in places less. As silt cont<strong>en</strong>ts are low, sand cont<strong>en</strong>ts <strong>of</strong> tops oils<br />
and and subsurface subsurface horizons horizons are high.<br />
Subsoils have yellowish brown colours with a range from light yellowish brown to strong brown<br />
and commonly have about 40% clay. Clay cont<strong>en</strong>ts ranges betwe<strong>en</strong> 30 and 64%. Reddish<br />
mottles start to appear appear betwe<strong>en</strong> about about 15 and 40 cm depth. In places plinthite occurs with in 150<br />
cm, cm, starting starting betwe<strong>en</strong> betwe<strong>en</strong> 75 and 140 cm cm depth. depth. Iron Iron concretions concretions occur occur in in <strong>the</strong> <strong>the</strong> deeper deeper subsoils, subsoils,<br />
starting starting at at irregular irregular depths, depths, appearing appearing betwe<strong>en</strong> betwe<strong>en</strong> 15 and 140 cm cm from from <strong>the</strong> <strong>the</strong> surface surface downwards. downwards. Next Next<br />
to <strong>the</strong>se concretions, quartz gravel and pieces <strong>of</strong> rott<strong>en</strong> rock occur in <strong>the</strong> deeper subsoils giving<br />
<strong>the</strong>m <strong>the</strong>m a texture <strong>of</strong> slightly gravelly to gravelly sandy clay loams to sandy clays.<br />
In In <strong>the</strong> <strong>the</strong> survey survey area, area, <strong>the</strong> <strong>the</strong> Ebimimbang soils typically typically occur occur at at altitudes below below 350 350 m and and are thus thus<br />
found found on on <strong>the</strong> <strong>the</strong> dissected erosional erosional plains, plains, uplands uplands and and isolated isolated hills hills in in this altitude zone. zone. Valley Valley<br />
bottom bottom soils occupy occupy up up to to 15% <strong>of</strong> <strong>the</strong>se areas but could usually not be mapped separately as<br />
most most valley valley bottoms bottoms are are narrow narrow « 250 250 m).<br />
Annex IV gives full pr<strong>of</strong>iles descriptions with analytical data <strong>of</strong> <strong>the</strong> Ebimimbang soils.<br />
5.2.4 Valley Bottom soils<br />
The valley bottoms are dominated by moderately deep to very deep, poorly to very poorly<br />
drained drained soils soils developed developed in unconsolidated rec<strong>en</strong>t rec<strong>en</strong>t alluvium. alluvium. The The soil soil pr<strong>of</strong>iles pr<strong>of</strong>iles are stratified<br />
showing showing alternations alternations <strong>of</strong> sand, loam and and clay clay layers. layers. Sand, Sand, however, however, is dominant. Flooding, Flooding, high high<br />
ground water water levels and and locally locally greyish greyish colours colours are characteristics characteristics <strong>of</strong> this soil soil type. type. Depth Depth <strong>of</strong><br />
groundwater level and soil texture could be used for fur<strong>the</strong>r subdivision <strong>of</strong> <strong>the</strong>se soils, although<br />
at reconnaissance scale scale this this is not feasible.<br />
42 42
have an udic moisture regime as explained above for <strong>the</strong> Oxisols. The Hapludults are <strong>the</strong> normal<br />
Udults. Ultisols with a kandic horizon have less that 40% clay in <strong>the</strong> top 18 cm and have a CEC<br />
clay in <strong>the</strong> subsoil <strong>of</strong> less than 16 meq/1 00 g: Kandiudults. The Paleudults are deeper than 150 cm<br />
and do not have a clay decrease with depth <strong>of</strong> more than 20%. Plintudults have 50% or more<br />
plinthite within 150 cm.<br />
The young Valley Bottom soils with high groundwater levels are classified as Aqu<strong>en</strong>ts. The sandy<br />
ones are <strong>the</strong> Psammaqu<strong>en</strong>ts and <strong>the</strong> loamy and clayey ones with irregular decrease in clay cont<strong>en</strong>ts<br />
with depth are <strong>the</strong> Fluvaqu<strong>en</strong>ts. Lithic Endoqu<strong>en</strong>ts are shallower than 50 cm. The valley bottom<br />
soils which are somewhat better drained are classified as Inceptisols. The Inceptisols <strong>of</strong> <strong>the</strong> tropics<br />
are <strong>the</strong> Tropepts and Dystropepts if <strong>the</strong>y have a base saturation <strong>of</strong> less than 50% in <strong>the</strong> subsoil. The<br />
Aquic Dystropepts have reduction and oxidation mottles within 100 cm.<br />
CPCS<br />
The three main soil types in <strong>the</strong> TCP research area can be placed in <strong>the</strong> 'Classe des Sols<br />
FerralIitiques'. These 'sols ferralIitiques' are developed in <strong>the</strong> humid tropics and are characterized<br />
by high cont<strong>en</strong>ts <strong>of</strong> <strong>the</strong> minerals kaolinite, gibbsite, goethite and hematite.<br />
The 'Classe des Sols Hydromorphes' is also found in <strong>the</strong> TCP research area. These soils are<br />
characterized by a zone <strong>of</strong> alternating oxidation-reduction conditions and/or a perman<strong>en</strong>t reduction<br />
zone (gley).<br />
The Nyangong soils and <strong>the</strong> majority <strong>of</strong> <strong>the</strong> Ebom soils meet <strong>the</strong> requirem<strong>en</strong>ts for <strong>the</strong> 'sous-classe<br />
des so Is ferrallitiques fortem<strong>en</strong>t desatures <strong>en</strong> (B)" which are soils with pH lower than 5 and base<br />
saturation lower than 20%. The Ebimimbang soils and some <strong>of</strong> <strong>the</strong> Ebom soils meet <strong>the</strong><br />
requirem<strong>en</strong>ts for <strong>the</strong> 'sous-classe des sols ferra<strong>II</strong>itiques moy<strong>en</strong>nem<strong>en</strong>t desatui'es <strong>en</strong> (B)" which are<br />
soils with pH around 5 and base saturation betwe<strong>en</strong> 20 and 40%. The majority <strong>of</strong> <strong>the</strong> Nyangong,<br />
Ebom and Ebimimbang pr<strong>of</strong>iles can be placed in <strong>the</strong> group 'groupe typique' and and'sous-groupe<br />
'sous-groupe<br />
jaune' <strong>of</strong> <strong>the</strong> system. In places <strong>the</strong>y are in <strong>the</strong> 'groupe remanie or rajeuni'. They are all developed<br />
on 'roches metamorphique' (Segal<strong>en</strong>, 1957).<br />
The Valley Bottom soils belong to <strong>the</strong> 'sous-classe des so Is hydromorphes mineraux ou peu<br />
humiferes' and <strong>the</strong>' groupes des so Is hydromorphes peu humiferes it gley'. The depth <strong>of</strong> <strong>the</strong> gley<br />
horizon determines <strong>the</strong> subgroup.<br />
5.3 SOIL PHYSICAL CHARACTERISTICS<br />
Several physical characteristics were measured to characterize <strong>the</strong> soils. In Annex <strong>II</strong>I <strong>the</strong> differ<strong>en</strong>t<br />
methods used for texture, bulk d<strong>en</strong>sity and water ret<strong>en</strong>tion (physical) analysis are pres<strong>en</strong>ted. Annex<br />
IV gives <strong>the</strong> analytical data <strong>of</strong> <strong>the</strong> sampled soil pr<strong>of</strong>iles. Table 5.3 pres<strong>en</strong>ts <strong>the</strong> ranges <strong>of</strong> clay, silt<br />
sand cont<strong>en</strong>ts and <strong>the</strong> average values <strong>of</strong> <strong>of</strong> bulk bulk d<strong>en</strong>sities and water ret<strong>en</strong>tions <strong>of</strong> <strong>the</strong> three three main soil soil<br />
types.<br />
5.3.1 Texture<br />
In Table 5.3 textures <strong>of</strong> <strong>the</strong> topsoils and subsoils <strong>of</strong> <strong>the</strong> most common soils are pres<strong>en</strong>ted. Clear<br />
clusters are pres<strong>en</strong>t: (i) Nyangong soils with topsoil clay cont<strong>en</strong>ts <strong>of</strong> about 45%, (ii) Ebom soils<br />
with intermediate clay and sand cont<strong>en</strong>ts <strong>of</strong> about 35% and 45% respectively in <strong>the</strong> topsoils and<br />
(iii) Ebimimbang soils with topsoil clay cont<strong>en</strong>ts <strong>of</strong> only 10%. Clay cont<strong>en</strong>ts increase with depth<br />
for all three soil types. The deeper subsoils (BC, CB or C horizons) show slightly lower clay<br />
cont<strong>en</strong>ts compared to <strong>the</strong> horizons directly above.<br />
45
Table 5.3 Soil physical physical characteristics <strong>of</strong> <strong>the</strong> Nyangong, Nyangong, Ebom and Ebimimbang soils<br />
Soil type type Depth Texture Texture Texture Texture Bulk Bulk d<strong>en</strong>sity AWe<br />
(clay%) (silt%) (silt%) (sand%) (g/cm3) (%)<br />
Nyangong I 35-70 10-20 10-40 1.03 10<br />
2 50-80 50-80 5-15 10-40 1.21 12<br />
3 1.26 7<br />
Ebom I 20-50 5-20 40-60 1.22 17<br />
2 35-60 35-60 5-15 30-50 1.37 16<br />
3 1.4 1.4 12<br />
Ebimimbang I 0-25 5-15 60-90 1.3 11<br />
2 20-45 5-15 40-80 1.55 15 15<br />
3 1.63 n.a.<br />
Soil depth classes: I = 0-20cm; 2 = 20-60 cm; 3 = 60-90cm. Bulk d<strong>en</strong>sity values are <strong>the</strong> average <strong>of</strong> at least 4<br />
observations. A AWC= WC= Available Water Cont<strong>en</strong>t (one or two observations per soil depth class).<br />
The Valley Bottom soils are dominated by a sandy texture, but in fact all all texture texture classes classes may may<br />
occur in in all possible possible sequ<strong>en</strong>ces. Stratification is characteristic for <strong>the</strong>se soils. In g<strong>en</strong>eral, g<strong>en</strong>eral, <strong>the</strong><br />
Valley Valley Bottom soils have have 5-30% clay and 40-90% sand sand in <strong>the</strong> topsoil. The subsurface horizons<br />
g<strong>en</strong>erally are more sandy.<br />
5.3.2 Bulk d<strong>en</strong>sity<br />
The ranges ranges in bulk bulk d<strong>en</strong>sities d<strong>en</strong>sities <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> soils soils in <strong>the</strong> TCP research research area area are 0.8 to lA g/cm3 in in <strong>the</strong><br />
topsoils topsoils (0-10 cm) and 1.0 to 1.7 g/cm g/cm 3 in <strong>the</strong> subsoils (20-90 cm) (Table 5.3). The bulk<br />
d<strong>en</strong>sities <strong>of</strong> all three three main soil soil types increase strongly with depth, depth, as as effects effects <strong>of</strong> cultivation cultivation and and<br />
organic matter matter cont<strong>en</strong>t decrease. decrease. The The increase <strong>of</strong> <strong>of</strong> <strong>the</strong> bulk d<strong>en</strong>sities with depth take place 'within<br />
25 25 cm from from <strong>the</strong> <strong>the</strong> surface. The The bulk d<strong>en</strong>sities <strong>of</strong> <strong>of</strong> <strong>the</strong> Nyangong/Ebom soils and <strong>the</strong> Ebimimbang<br />
soils are within <strong>the</strong> normal range <strong>of</strong> 1.0 to 1.6 g/cm g/cm3 3 and 1.2 to 1.8 g/cm g/cm 3 as giv<strong>en</strong> by Landon<br />
(1991) for clayey and sandy soils, respectively.<br />
3 as giv<strong>en</strong> by Landon<br />
(1991) for clayey and sandy soils, respectively.<br />
Average values <strong>of</strong> bulk d<strong>en</strong>sities for <strong>the</strong> Nyangong, Ebom and Ebimimbang soils at three depths<br />
(0-20 cm, 20-60 cm and 60-90cm) are giv<strong>en</strong> in Table 5.3. The Nyangong topsoils have bulk<br />
d<strong>en</strong>sities <strong>of</strong> around 1.0 g/cm3, and below 20 cm <strong>the</strong> bulk d<strong>en</strong>sities increase to values <strong>of</strong> 1.2 to<br />
1.3 g/cm3. The topsoils and subsurface horizons <strong>of</strong> <strong>the</strong> Ebom soils have bulk d<strong>en</strong>sities around<br />
1.2 and lA g/cm3 Average values <strong>of</strong> bulk d<strong>en</strong>sities for <strong>the</strong> Nyangong, Ebom and Ebimimbang soils at three depths<br />
(0-20 cm, 20-60 cm and 60-90cm) are giv<strong>en</strong> in Table 5.3. The Nyangong topsoils have bulk<br />
d<strong>en</strong>sities <strong>of</strong> around 1.0 g/cm3, and below 20 cm <strong>the</strong> bulk d<strong>en</strong>sities increase to values <strong>of</strong> 1.2 to<br />
1.3 g/cm<br />
, respectively. Bulk d<strong>en</strong>sities <strong>of</strong> <strong>the</strong> Ebimimbang soils are <strong>the</strong> highest <strong>of</strong> <strong>the</strong><br />
TCP research area, i.e. 1.3 g/cm 3 for <strong>the</strong> topsoils and 1.5 to 1.7 g/cm 3 for <strong>the</strong> subsoils. There is<br />
thus an increasing bulk d<strong>en</strong>sity with a decreasing clay cont<strong>en</strong>t.<br />
3 • The topsoils and subsurface horizons <strong>of</strong> <strong>the</strong> Ebom soils have bulk d<strong>en</strong>sities around<br />
1.2 and 1.4 g/cm3 , respectively. Bulk d<strong>en</strong>sities <strong>of</strong> <strong>the</strong> Ebimimbang soils are <strong>the</strong> highest <strong>of</strong> <strong>the</strong><br />
TCP research area, i.e. 1.3 g/cm3 for <strong>the</strong> topsoils and 1.5 to 1.7 g/cm3 for <strong>the</strong> subsoils. There is<br />
thus an increasing bulk d<strong>en</strong>sity with a decreasing clay cont<strong>en</strong>t.<br />
The Ebimimbang soils have less stable aggregates than <strong>the</strong> Ebom and Nyangong soils (Waterloo<br />
et al., 1997), resulting in vertical clay movem<strong>en</strong>t and lower permeability <strong>of</strong> <strong>the</strong> Ebimimbang<br />
soils. The higher bulk d<strong>en</strong>sities <strong>of</strong> <strong>the</strong> Ebimimbang Ebimimbang soils are explained by <strong>the</strong> lower aggregate<br />
stability and higher sand sand cont<strong>en</strong>ts <strong>of</strong> <strong>the</strong>se soils.<br />
Topsoils under agriculture have decreased organic matter cont<strong>en</strong>ts and less roots resulting in<br />
higher bulk d<strong>en</strong>sities d<strong>en</strong>sities compared to id<strong>en</strong>tical soils soils under forest (pers. comm. comm. Yemefack, 1996). 1996).<br />
46
The pH2 <strong>of</strong> <strong>the</strong> Nyangong Nyangong topsoils topsoils and subsoils subsoils is in <strong>the</strong> range <strong>of</strong> 3.5 to 4.5 (extremely (extremely acid).<br />
Khanna and Ulrich (1984) (I 984) define <strong>the</strong> pH range 3.8-4.2 as <strong>the</strong> aluminum buffer range, which<br />
means that aluminum is exchanged against hydrog<strong>en</strong> with decreasing pH.<br />
The pH <strong>of</strong> <strong>the</strong> Ebom soils is 3.5-5 in <strong>the</strong> topsoils and 4-5 in <strong>the</strong> subsurface horizons (very<br />
strongly to extremely acid). The pH values <strong>of</strong> <strong>the</strong> Ebom soils are only slightly higher than those<br />
<strong>of</strong> <strong>the</strong> Nyangong soils, and <strong>the</strong>y are intermediate betwe<strong>en</strong> <strong>the</strong> Nyangong and Ebimimbang soils.<br />
The pH values <strong>of</strong> <strong>the</strong> Ebimimbang topsoils are 1-1.5 units higher than those <strong>of</strong> <strong>the</strong> Nyangong<br />
and Ebom soils. The topsoil pH is 5-6 (medium to strongly acidic), and <strong>the</strong> subsurface soil pH<br />
is 4.5-5.5 (strongly to very strongly acid). This marked gradi<strong>en</strong>t in pH with depth is<br />
characteristic for soils in <strong>the</strong> cation exchange capacity buffer (4.2-5). Cations are exchanged<br />
against hydrog<strong>en</strong> to buffer changes in pH. Soils with pH values within this range are<br />
characterized by sharp differ<strong>en</strong>ces in chemical characteristics (Khanna and Ulrich, 1984), which<br />
is confirmed by <strong>the</strong> base saturation data <strong>of</strong> Ebimimbang topsoils and subsurface horizons.<br />
The Valley Bottom soil has pH values that resemble those <strong>of</strong> <strong>the</strong> Ebimimbang soil. The topsoil<br />
pH is betwe<strong>en</strong> 5 and 6 and <strong>the</strong> subsurface pH is betwe<strong>en</strong> 4.5 and 5.5.<br />
All subsoils have pH values betwe<strong>en</strong> 3.5 and 5.5. In <strong>the</strong>se pH ranges manganese (Mn),<br />
aluminum (AI), iron (Fe) and trace elem<strong>en</strong>ts as copper (Cu), zinc (Zn) and borium (B) are<br />
available for plant growth (Euroconsult, 1989; Landon, 1991). In g<strong>en</strong>eral <strong>the</strong> aluminum<br />
conc<strong>en</strong>trations <strong>of</strong> <strong>the</strong> soils in <strong>the</strong> TCP research area are high and exchangeable potassium (K),<br />
magnesium (Mg) and calcium (Ca) conc<strong>en</strong>trations are very low in <strong>the</strong> soil solution (see Table<br />
5.4b.). Crops grown on <strong>the</strong>se soils may experi<strong>en</strong>ce nutri<strong>en</strong>t defici<strong>en</strong>cies. High aluminum<br />
conc<strong>en</strong>trations in <strong>the</strong> soil solution are toxic to many crops. Low pH values as found in <strong>the</strong><br />
Nyangong soils, facilitate <strong>the</strong> formation <strong>of</strong> iron and phosphate aluminium compounds. This<br />
phosphate phosphate is not available to plants. The somewhat higher topsoil pH values might be explained<br />
by rec<strong>en</strong>t agricultural activities which include <strong>the</strong> burning <strong>of</strong> vegetation by which alkaline ashes<br />
are are formed. formed.<br />
5.4.2 Organic carbon and total nitrog<strong>en</strong><br />
The organic carbon and related total nitrog<strong>en</strong> cont<strong>en</strong>ts <strong>of</strong> <strong>the</strong> topsoils differ significantly<br />
betwe<strong>en</strong> betwe<strong>en</strong> <strong>the</strong> <strong>the</strong> four four soil soil types. types. The The observed observed organic organic carbon carbon range within within <strong>the</strong> survey survey area area is 2%-9% 2%-9%<br />
and <strong>the</strong> total nitrog<strong>en</strong> cont<strong>en</strong>ts range from 0.15%-0.5%. The topsoils have significantly higher<br />
organic organic carbon carbon and and total total nitrog<strong>en</strong> nitrog<strong>en</strong> cont<strong>en</strong>ts cont<strong>en</strong>ts than <strong>the</strong> subsoils. subsoils. Fig. 5.2. shows shows <strong>the</strong> <strong>the</strong> relation relation betwe<strong>en</strong> betwe<strong>en</strong><br />
organic carbon and total nitrog<strong>en</strong> conc<strong>en</strong>trations for for all all samples. The The CIN value calculated with<br />
regression regression analysis analysis on all data is 13 (R2 = 0.94).<br />
The Nyangong topsoils have organic carbon cont<strong>en</strong>ts betwe<strong>en</strong> 4% and 9% and total nitrog<strong>en</strong><br />
cont<strong>en</strong>ts betwe<strong>en</strong> 0.25% and 0.4%. The CIN values <strong>of</strong> <strong>the</strong> topsoils are betwe<strong>en</strong> 12 and 18. The<br />
subsurface horizons have organic carbon cont<strong>en</strong>ts betwe<strong>en</strong> 1 1% % and 3 3% % and total nitrog<strong>en</strong><br />
cont<strong>en</strong>ts betwe<strong>en</strong> 0.1 % and 0.15% (Table 5.4a.). In <strong>the</strong> subsoils <strong>the</strong> organic carbon cont<strong>en</strong>t drops<br />
rapidly to below 0.5%. The CIN values <strong>of</strong> <strong>the</strong> subsurface horizons are in <strong>the</strong> range <strong>of</strong> 10 to 14.<br />
2 With pH, we mean pH(H 20), 20), unless o<strong>the</strong>rwise indicated.<br />
48
The Valley Bottom soils have organic carbon cont<strong>en</strong>ts cont<strong>en</strong>ts <strong>of</strong> 2.5-6.5% 2.5-6.5% in <strong>the</strong> topsoils. The total<br />
nitrog<strong>en</strong> cont<strong>en</strong>ts <strong>of</strong> <strong>the</strong> topsoil are comparable with <strong>the</strong> o<strong>the</strong>r soils. The subsurface horizons<br />
show organic carbon and total nitrog<strong>en</strong> cont<strong>en</strong>ts similar to those <strong>of</strong> <strong>the</strong> Ebom and Ebimimbang<br />
soils.<br />
5.4.3 Available and total phosphorous<br />
The available phosphorous cont<strong>en</strong>t in <strong>the</strong> topsoils <strong>of</strong> <strong>the</strong> Nyangong soils ranges betwe<strong>en</strong> 4 and<br />
11 ppm (low), in <strong>the</strong> Ebom and Ebimimbang soils betwe<strong>en</strong> 10 and 26 ppm (moderate) and in <strong>the</strong><br />
Valley Bottom soils betwe<strong>en</strong> 30 and 60 ppm (moderate to high). With depth, available<br />
phosphorous cont<strong>en</strong>ts drop rapidly to values below 5 ppm and are invariably approaching 0 in<br />
all subsoils.<br />
Total phosphorous cont<strong>en</strong>ts <strong>of</strong> <strong>the</strong> topsoils are high in <strong>the</strong> Nyangong soils and range betwe<strong>en</strong><br />
400 and 600 ppm. With depth, <strong>the</strong>se values go down to 50-250 ppm. The Ebom and Ebimimbang<br />
soils have 150-400 ppm total phosphorous in <strong>the</strong> topsoils and 50-250 ppm in <strong>the</strong>ir subsoils. Total<br />
phosphorous cont<strong>en</strong>ts <strong>of</strong> <strong>the</strong> Valley Bottom soils are not available.<br />
Higher available phosphorous cont<strong>en</strong>ts coincide with higher pH values as at higher pH values<br />
phosphorous is less fixed in aluminium and iron complexes than at lower pH ranges. The higher<br />
available phosphorous cont<strong>en</strong>ts <strong>of</strong> <strong>the</strong> Valley Bottoms are explained by colluvial <strong>en</strong>richm<strong>en</strong>t.<br />
Table 5.4b 5.4b Ranges in some chemical chemical characteristics <strong>of</strong> <strong>the</strong> four soil types types in <strong>the</strong> TCP TCP research<br />
area<br />
Soil type Depth Depth K+ Mg++ Ca++ TEB Al+++ Al+++ ECEC ECEC CEC CEC BS<br />
(%)<br />
Nyangong 1 0.1-0.5 0.2-0.8 1-2 1.5-3.5 4-9 6-10 10-20 10-20<br />
2 0-0.1 0-0.5 0.2-0.6 0.5-1.2 2-6 5-7 6-9 5-15<br />
Ebom 1 0.1-0.9 0.4-1.6 0.5-4 2-5 0.5-6 4-9 12-25 10-50<br />
2 0-0.2 0-0.5 0-0.5 0.3-1 2-5 3-6 5-8 5-20<br />
Ebimimbang 1 0.1-0.7 0-1.5 1-8 3-7 0-3 3-10 4-12 50-100<br />
2 0-0.2 0-0.5 0-2 0.2-1.5 1-2.5 1.5-1 2-6 10-70<br />
Valley 0-0.5 0.3-1.5 0.5-4 4.5-6 0-3 5-7.5 7-17 15-50<br />
Bottom 2 0-0.1 0-0.2 0-0.5 0.5-0.8 0-1.5 0.5-2 1-8 20-40<br />
Soil depth: 1 = topsoil, g<strong>en</strong>erally 0-10 cm; 2 = subsurface horizon <strong>of</strong> about 20-60 cm depth. TEB = Total<br />
Exchangeable Bases. ECEC = Effective Cation Exchange Capacity. CEC = Cation Exchange Capacity. BS = Base<br />
Saturation. All values, except BS, in meq per 100 g.<br />
5.4.4 Cation exchange capacity and exchangeable bases<br />
The cation exchange capacities (CEC) <strong>of</strong> <strong>the</strong> topsoils in <strong>the</strong> study area are low to moderate with<br />
CEC values <strong>of</strong> 4-20 mellOO gr soil. With depth <strong>the</strong> CECs drop rapidly to low levels <strong>of</strong> 1 to 9<br />
me/lOO gr in <strong>the</strong> subsurface horizons to ev<strong>en</strong> lower levels in <strong>the</strong> subsoils. The relatively higher<br />
CEC values occur in <strong>the</strong> topsoils topsoils <strong>of</strong> <strong>the</strong> Nyangong Nyangong and Ebom soils and are betwe<strong>en</strong> betwe<strong>en</strong> 10 and 25<br />
mell me/lOO 00 g soil. These higher values are directly related to <strong>the</strong> higher organic matter levels <strong>of</strong><br />
<strong>the</strong>se soils.<br />
The exchange exchange complex complex is dominated dominated by aluminium aluminium (AI) and Al saturation saturation perc<strong>en</strong>tages perc<strong>en</strong>tages <strong>of</strong> 30 to<br />
80% are common. The highest saturation values occur in <strong>the</strong> soils with <strong>the</strong> lowest pH values,<br />
50
Next to kaolinite, <strong>the</strong> aluminum hydroxide gibbsite, is moderately abundant in <strong>the</strong> Nyangong<br />
and Ebom soils. Gibbsite forms in richer par<strong>en</strong>t material (Driess<strong>en</strong> and Dudal, 1989; 1989; Mohr et<br />
al., 1972; van Kekem et al., 1997). The drainage conditions <strong>of</strong> <strong>the</strong> Ebimimbang soils, are less<br />
good wh<strong>en</strong> compared to <strong>the</strong> two o<strong>the</strong>r soil types. This might be <strong>the</strong> explanation for <strong>the</strong><br />
differ<strong>en</strong>ce in gibbsite cont<strong>en</strong>ts <strong>of</strong> <strong>the</strong> differ<strong>en</strong>t soil types.<br />
Vermiculite, chlorite and smectite are clay minerals which are abs<strong>en</strong>t or only pres<strong>en</strong>t in<br />
relatively small amounts in <strong>the</strong> TCP research area. area. Micas (illite) are moderately abundant in<br />
some soil samples, but no relation relation is found with <strong>the</strong> differ<strong>en</strong>t soil types. Feldspars and quartz<br />
are abs<strong>en</strong>t or only pres<strong>en</strong>t in small amounts <strong>the</strong> clay fractions.<br />
The iron hydroxide goethite is moderately abundant in all soils, whereas whereas <strong>the</strong> iron oxide hematite<br />
is abs<strong>en</strong>t in <strong>the</strong> three main soil types <strong>of</strong> <strong>the</strong> TCP area. Goethite is formed under a soil climate<br />
with suffici<strong>en</strong>t moisture in <strong>the</strong> dry season season ev<strong>en</strong> if <strong>the</strong> soils are well drained. It gives <strong>the</strong> soil a<br />
yellowish brown colour (Bilong, 1992). Driess<strong>en</strong> and Dudal (1989) (1989) state that goethite is formed<br />
wh<strong>en</strong> <strong>the</strong> iron conc<strong>en</strong>tration is low, <strong>the</strong> organic matter cont<strong>en</strong>t is high, <strong>the</strong> temperature is low<br />
and/or soil pH is lower than 4.0.<br />
5.4.6 Nutri<strong>en</strong>t cont<strong>en</strong>ts<br />
Combining bulk d<strong>en</strong>sity data data and chemical chemical data makes it possible to calculate <strong>the</strong> total total amounts<br />
<strong>of</strong> nutri<strong>en</strong>ts pot<strong>en</strong>tially available for plant growth. The data give an indication <strong>of</strong> <strong>the</strong> fertility <strong>of</strong><br />
<strong>the</strong> differ<strong>en</strong>t soils. The calculated nutri<strong>en</strong>t cont<strong>en</strong>ts for <strong>the</strong> three main soil types are averages <strong>of</strong><br />
four four to six pr<strong>of</strong>iles. Table 5.5. 5.5. shows <strong>the</strong> <strong>the</strong> nutri<strong>en</strong>t cont<strong>en</strong>ts cont<strong>en</strong>ts in kg/ha for a soil column <strong>of</strong> 1 meter<br />
deep. The majority <strong>of</strong> <strong>the</strong>se nutri<strong>en</strong>ts, however, are conc<strong>en</strong>trated conc<strong>en</strong>trated in <strong>the</strong> upper 20 cm <strong>of</strong> <strong>the</strong> soil<br />
pr<strong>of</strong>ile. pr<strong>of</strong>ile.<br />
The Nyangong soil has a relatively high nitrog<strong>en</strong> cont<strong>en</strong>t (12.5 ton/ha), whereas whereas available<br />
phosphorous and potassium are pres<strong>en</strong>t in relatively relatively small amounts <strong>of</strong> 8 and 360 kg respectively<br />
(Table 5.5.). Magnesium and calcium amounts are 195 and 1065 kg/ha, respectively. The Ebom<br />
soil has less less total nitrog<strong>en</strong> (8900 (8900 kg/ha), but a moderate amount <strong>of</strong> phosphorous (28 kg/ha). The<br />
Ebimimbang soil also has a moderate amount <strong>of</strong> available phosphorous (24 (24 kg/ha) but <strong>the</strong> total<br />
nitrog<strong>en</strong> nitrog<strong>en</strong> amount is low (7000 kg/ha). The pot<strong>en</strong>tially available K, Mg and Ca amounts are in <strong>the</strong><br />
same order <strong>of</strong> magnitude for all three soils.<br />
Table 5.5 5.5 Average nutri<strong>en</strong>t cont<strong>en</strong>ts <strong>of</strong> <strong>the</strong> Nyangong, Ebom and Ebimimbang soils in kg/ha kg/ha<br />
(soil column <strong>of</strong> <strong>of</strong> 1m)<br />
Soil type Total Total N Available P K Mg Ca<br />
Nyangong soil (n=6) 12500 8 8 360 195 1065<br />
(7371-24338) (3-16) (168-805) (168-805) (86-336) (607-1876)<br />
Ebom soil soil (n=4) 8900 8900 28 755 175 1785<br />
(5616-13022) (5-59) (361-1601) (60-306) (867-3558)<br />
Ebimimbang soil soil (n=6) 7000 24 370 165 165 1810<br />
( 4963-8757) (11-42) (11-42) (176-395) (27-535) ( (1295-2088) 1295-2088)<br />
The nutri<strong>en</strong>t nutri<strong>en</strong>t cont<strong>en</strong>ts <strong>of</strong> <strong>the</strong> soils in <strong>the</strong> TCP research area area are comparable with data data from o<strong>the</strong>r<br />
studies on on humid tropical forest soils (Anderson and Sp<strong>en</strong>cer, 1991; Gillman et al., 1985).<br />
52
The combination <strong>of</strong> block faulting and <strong>the</strong> process <strong>of</strong> d<strong>en</strong>udation (mechanical (mechanical and and chemical<br />
erosion) have resulted in planation or erosion levels <strong>of</strong> differ<strong>en</strong>t age, which might be <strong>the</strong> <strong>the</strong><br />
explanation for <strong>the</strong> differ<strong>en</strong>ces differ<strong>en</strong>ces <strong>en</strong>countered in <strong>the</strong> landforms and soils in <strong>the</strong> TCP research area.<br />
The eastern eastern region <strong>of</strong> <strong>the</strong> TCP region has be<strong>en</strong> lifted upwards in relation relation to to <strong>the</strong> western lowlands lowlands<br />
along NE-SW ori<strong>en</strong>tated faults. The d<strong>en</strong>udation, d<strong>en</strong>udation, which can be be called (valley floor)<br />
pedim<strong>en</strong>tation (Zonneveld, 1981; Embrechts and Dapper, 1987), has resulted in almost flat<br />
erosional plains with inselbergs in <strong>the</strong> <strong>the</strong> western lowlands and in a very very dissected landscape in <strong>the</strong> <strong>the</strong><br />
mountainous eastern region. This dissected dissected landscape has be<strong>en</strong> developed originally from an old<br />
erosional plain. The progressive erosion (slope retreat) from West to East has resulted in very<br />
small differ<strong>en</strong>ces in altitude (Iow relief int<strong>en</strong>sity) int<strong>en</strong>sity) betwe<strong>en</strong> <strong>the</strong> western part <strong>of</strong> <strong>the</strong> TCP research<br />
area and and <strong>the</strong> Atlantic Ocean, i.e. <strong>the</strong> <strong>the</strong> erosion basis. It is concluded that <strong>the</strong> landscape in <strong>the</strong> <strong>the</strong><br />
western part <strong>of</strong> <strong>the</strong> TCP research area area is younger than than <strong>the</strong> <strong>the</strong> eastern one.<br />
The soil forming processes, which are m<strong>en</strong>tioned in section 5.5.2., may have be<strong>en</strong> causing<br />
spatial variations. A downward tr<strong>en</strong>d from West to East in rainfall and temperature may have<br />
caused differ<strong>en</strong>ces in int<strong>en</strong>sity and nature <strong>of</strong> <strong>the</strong> soil forming forming processes. This tr<strong>en</strong>d, however,<br />
is locally disturbed by <strong>the</strong> topography. Lower amounts <strong>of</strong> rain are observed around <strong>Bipindi</strong><br />
(Waterloo et al., 1997) and can be an additional explanation for richer and less deep soils in<br />
<strong>the</strong>se western lowlands.<br />
Additionally, <strong>the</strong> age <strong>of</strong> <strong>the</strong> landscapes within <strong>the</strong> TCP research area varies and as a result, <strong>the</strong><br />
soil forming processes differ in <strong>the</strong>ir periods <strong>of</strong> activity. Hydrolysis in <strong>the</strong> western lowlands is<br />
not in as advanced state as in <strong>the</strong> eastern region. Moreover, <strong>the</strong> importance <strong>of</strong> soil forming<br />
processes processes such as plinthite formation and clay illuviation decreases from West to East. Besides<br />
<strong>the</strong> variation in rainfall and temperature and <strong>the</strong> differ<strong>en</strong>t ages <strong>of</strong> <strong>the</strong> landscapes in <strong>the</strong> research<br />
area, <strong>the</strong> spatial distribution <strong>of</strong> <strong>the</strong> soil forming processes is also influ<strong>en</strong>ced by topographical<br />
position. All <strong>the</strong>se factors result in in differ<strong>en</strong>ces in soil drainage, drainage, texture and soil depth. depth.<br />
The soils are relatively uniform in colour but differ differ in texture, depth or drainage. The variation<br />
in texture seems to be related to to differ<strong>en</strong>ces in <strong>the</strong> age <strong>of</strong> <strong>the</strong> landscape. Perhaps small, during<br />
<strong>the</strong> <strong>the</strong> survey not noticed, differ<strong>en</strong>ces in texture and mineralogical composition <strong>of</strong> par<strong>en</strong>t material<br />
could also be important. Younger areas like <strong>the</strong> western lowlands have less wea<strong>the</strong>red soils,<br />
resulting in coarser textured textured soils (Ebimimbang soils), soils), whereas whereas <strong>the</strong> deeply wea<strong>the</strong>red soils in <strong>the</strong><br />
eastern region region have a predominant predominant clayey clayey texture. The less wea<strong>the</strong>red soils are richer in in<br />
nutri<strong>en</strong>ts, have higher pHs and clear clay cutans (evid<strong>en</strong>ce <strong>of</strong> active clay clay movem<strong>en</strong>t to <strong>the</strong><br />
subsoils) and are less deep deep than than <strong>the</strong> <strong>the</strong> clayey textured textured Nyangong soils formed in an older<br />
landscape.<br />
Drainage differ<strong>en</strong>ces are especially related to topographical positions. The valleys have poorly<br />
to very poorly drained soils, whereas on <strong>the</strong> o<strong>the</strong>r topographical positions, moderately well to<br />
well drained soils occur.<br />
The variability in soil depth may be large at small distances for which relative resistance to<br />
wea<strong>the</strong>ring <strong>of</strong> <strong>the</strong> <strong>the</strong> par<strong>en</strong>t rock and <strong>the</strong> <strong>the</strong> degree <strong>of</strong> fracturing may may be an explanation.<br />
Fur<strong>the</strong>r research (e.g. clay mineralogy, geomorphological processes, geology) is needed to<br />
elaborate <strong>the</strong>se <strong>the</strong>ories. <strong>the</strong>ories. Also, research on <strong>the</strong> variation <strong>of</strong> soil depth with topographic topographic position<br />
(cat<strong>en</strong>a) (cat<strong>en</strong>a) will will be very useful for a better understanding <strong>of</strong> processes which are active in <strong>the</strong> TCP<br />
research area.<br />
54
5.5.2 Soil g<strong>en</strong>esis<br />
The following soil forming processes have be<strong>en</strong> contributing to soil formation in <strong>the</strong> TCP<br />
research area: formation A-horizon, hydrolysis, ferralitization, kaolinitization, plinthite and<br />
laterite formation, eluvation and illuvation <strong>of</strong> clay and oxidation/reduction processes.<br />
Accumulation <strong>of</strong> litter which is decomposed by soil flora and fauna in <strong>the</strong> mineral topsoils<br />
results in <strong>the</strong> formation <strong>of</strong> an A-horizon. Mineralization <strong>of</strong> organic matter releases nutri<strong>en</strong>ts<br />
which can be tak<strong>en</strong> up by <strong>the</strong> surrounding vegetation. The process <strong>of</strong> decomposition,<br />
mineralization and uptake by <strong>the</strong> vegetation is relatively quick, <strong>the</strong>refore A-horizons are thin.<br />
Low pH levels, however, will retard <strong>the</strong> decomposition and organic matter may accumulate<br />
(Mohr et al., 1972). The chemical fertility <strong>of</strong> <strong>the</strong> tropical soil is strongly related to <strong>the</strong> pres<strong>en</strong>ce<br />
<strong>of</strong> organic matter in <strong>the</strong> topsoil because <strong>of</strong> its storage and release capacity <strong>of</strong> nutri<strong>en</strong>ts. In <strong>the</strong><br />
TCP area <strong>the</strong>re are significant differ<strong>en</strong>ces in organic carbon cont<strong>en</strong>ts betwe<strong>en</strong> <strong>the</strong> differ<strong>en</strong>t<br />
topsoils (section 5.4.2.).<br />
The main soil forming process in <strong>the</strong> TCP area has be<strong>en</strong> hydrolysis (cations in <strong>the</strong> primary<br />
silicate structures <strong>of</strong> minerals are exchanged against H+-ions). The hydrog<strong>en</strong> ion weak<strong>en</strong>s <strong>the</strong><br />
mineral structure, facilitating <strong>the</strong> dissolution <strong>of</strong> Si and Al from <strong>the</strong> clay lattices. Ferralitization<br />
or desilication is hydrolysis in an advanced stage. A combination <strong>of</strong> slow release and subsequ<strong>en</strong>t<br />
leaching <strong>of</strong> cations and silica keeps <strong>the</strong> conc<strong>en</strong>tration in <strong>the</strong> soil solution low. If <strong>the</strong> soil<br />
temperature is high and percolation is int<strong>en</strong>se, ultimately all wea<strong>the</strong>rable primary minerals will<br />
be removed from <strong>the</strong> soil mass. Less soluble compounds such as iron and aluminum oxides and<br />
hydroxides, as well as coarse quartz grains, remain behind (Driess<strong>en</strong> and Dudal, 1989; Mohr et<br />
al., 1972). A low pH, low conc<strong>en</strong>trations <strong>of</strong> dissolved wea<strong>the</strong>ring products in <strong>the</strong> soil solution<br />
(low EC - values) and geomorphic stability over prolonged periods <strong>of</strong> time are conditions which<br />
accelerate <strong>the</strong> process <strong>of</strong> ferralitization (Driess<strong>en</strong> and Dudal, 1989). All <strong>the</strong>se conditions are<br />
pres<strong>en</strong>t in <strong>the</strong> TCP area. Due to <strong>the</strong> pres<strong>en</strong>ce <strong>of</strong> gneiss (acid rock) with few easily wea<strong>the</strong>rable<br />
minerals and much quartz, ferralitization proceeds much slower. Although much silica<br />
disappears through leaching (desilication), silica cont<strong>en</strong>ts remain higher than in soils formed on<br />
basic material. This silica combines with aluminum to <strong>the</strong> 1: 1 clay mineral kaolinite, which is<br />
called <strong>the</strong> kaolinitization process. Gibbsite is normally abs<strong>en</strong>t. It is however, formed under<br />
freely drained conditions and from richer rocks. The dominant minerals in <strong>the</strong> soils in <strong>the</strong> TCP<br />
research area are kaolinite, goethite (FEO(OH» and gibbsite (AI(OH)3)' The colour <strong>of</strong> <strong>the</strong> soils,<br />
orange to yellowish brown, is determined mainly by <strong>the</strong> pres<strong>en</strong>ce <strong>of</strong> goethite (section 5.4.5.).<br />
Hematite (FeP3)' (Fe20 3), which gives <strong>the</strong> soil a bright-red colour, is not observed in <strong>the</strong> TCP research<br />
area.<br />
Plinthite is an iron-rich, humus-poor mixture <strong>of</strong> clay and quartz. It is formed by <strong>the</strong> (relative<br />
and/or absolute) accumulation <strong>of</strong> sesquioxides (i.e. removal <strong>of</strong> silica and bases by ferralitization<br />
and/or <strong>en</strong>richm<strong>en</strong>t from outside) and <strong>the</strong> segregation <strong>of</strong> iron mottles (alternating reduction and<br />
oxidation). In <strong>the</strong> TCP research area plinthite is regularly found on <strong>the</strong> lower slopes betwe<strong>en</strong> 40<br />
and 500 meters altitude (uplands and dissected erosional plains). Within <strong>the</strong> Ebimimbang soils,<br />
a subtype can be distinguished with plinthite in <strong>the</strong> upper 125 cm. Laterite formation is <strong>the</strong><br />
hard<strong>en</strong>ing <strong>of</strong> plinthite to laterite. The main processes are <strong>the</strong> crystallization <strong>of</strong> amorphous iron<br />
compounds to aggregates <strong>of</strong> iron oxide minerals and <strong>the</strong> dehydration <strong>of</strong> <strong>of</strong> goethite to hematite hematite and<br />
<strong>of</strong> gibbsite to boehmite (Aleva, 1994; Driess<strong>en</strong> and Dudal, 1989). Laterite gravels are pres<strong>en</strong>t<br />
in limited amounts in <strong>the</strong> TCP research area. The laterite gravels are remnants <strong>of</strong> old eroded<br />
surfaces. Ferruginated rock fragm<strong>en</strong>ts are more common.<br />
55
Clay eluviationlilluviation is <strong>the</strong> redistribution <strong>of</strong> clay in <strong>the</strong> pr<strong>of</strong>ile, resulting in an increase in<br />
clay cont<strong>en</strong>t with depth. Mobilized clay is transported downward and deeper in <strong>the</strong> pr<strong>of</strong>ile where<br />
it is immobilized (Driess<strong>en</strong> and Dudal, 1989). Cutans <strong>of</strong> clay on <strong>the</strong> structural elem<strong>en</strong>ts in <strong>the</strong><br />
subsoil subsoil are evid<strong>en</strong>ce for rec<strong>en</strong>t illuviation. Biological activity may destruct <strong>the</strong>se clay cutans. cutans.<br />
These cutans are mainly found in <strong>the</strong> Ebimimbang soils in <strong>the</strong> western lowlands in <strong>the</strong> TCP<br />
research area (40-350 m as!). All soils in <strong>the</strong> TCP research area have a clay increase with depth,<br />
but cutans are rarely found in <strong>the</strong> eastern part. Clay movem<strong>en</strong>t is probably related to <strong>the</strong> past<br />
wh<strong>en</strong> <strong>the</strong> soil was still less wea<strong>the</strong>red and soil pH was somewhat higher than at pres<strong>en</strong>t (van<br />
Kekem et al., 1997).<br />
In <strong>the</strong> oxidation phase, <strong>the</strong> pres<strong>en</strong>ce <strong>of</strong> oxyg<strong>en</strong> leads to <strong>the</strong> transformation <strong>of</strong> soluble ferrous<br />
compounds to ferric compounds. These precipitate on soil particles, giving <strong>the</strong> soil its reddish<br />
colour. The reverse occurs during <strong>the</strong> <strong>the</strong> reduction phase. The lack <strong>of</strong> oxyg<strong>en</strong> oxyg<strong>en</strong> causes causes dissolution<br />
<strong>of</strong> ferric compounds, giving <strong>the</strong> soil <strong>the</strong> colour colour <strong>of</strong> non-ferrous minerals, forming its matrix (grey, (grey,<br />
olive or blue matrix matrix colours). This soil soil forming process <strong>of</strong> oxidation-reduction is associated with<br />
<strong>the</strong> fluctuation <strong>of</strong> <strong>the</strong> groundwater table. In <strong>the</strong> zone with alternating oxidizing and reducing<br />
conditions, mottles are <strong>of</strong>t<strong>en</strong> formed (Driess<strong>en</strong> and Dudal, 1989). This soil forming process is<br />
important in <strong>the</strong> Valley Bottom soils.<br />
56
6. VEGETATION<br />
6.1 LITERATURE REVIEW<br />
Flora and vegetation <strong>of</strong> Cameroon are relatively well known. The most relevant studies for <strong>the</strong><br />
pres<strong>en</strong>t vegetation inv<strong>en</strong>tory are Letouzey's 'Etude Phytogeographique du Cameroun' (1968) and<br />
his 'Carte Phytogeographique du Cameroun au 1 :500,000' (1985).<br />
The TCP research area is part <strong>of</strong> <strong>the</strong> Guineo-Congolian domain <strong>of</strong> d<strong>en</strong>se humid evergre<strong>en</strong> forests<br />
(see 2.7) and for <strong>the</strong> greater part belongs to <strong>the</strong> Biafran Atlantic district (low and medium altitude).<br />
Only along <strong>the</strong> fringes elem<strong>en</strong>ts <strong>of</strong> <strong>the</strong> low and medium altitude Littoral Atlantic district may be<br />
found. Individual small summit areas belong to <strong>the</strong> submontane zone <strong>of</strong> <strong>the</strong> Guineo-Congolian<br />
domain (Letouzey, 1968, 1985).<br />
In Table 6.1, <strong>the</strong> original fr<strong>en</strong>ch d<strong>en</strong>ominations <strong>of</strong> <strong>the</strong> districts are pres<strong>en</strong>ted, toge<strong>the</strong>r with <strong>the</strong> in<br />
<strong>the</strong> TCP area repres<strong>en</strong>ted formations. In Figure 6.1 <strong>the</strong> area relevant to <strong>the</strong> pres<strong>en</strong>t survey <strong>of</strong><br />
Letouzey's (1985) phytogeographical map is reproduced. In <strong>the</strong> following a brief description <strong>of</strong><br />
<strong>the</strong> differ<strong>en</strong>t vegetational zones is giv<strong>en</strong>.<br />
Table 6.1 Forest types <strong>of</strong> <strong>the</strong> TCP research area and its surrounding; 1 :500,000<br />
phytogeographical map (Letouzey, 1985)<br />
Region Guineo-Congolaise<br />
Etage submontagnard (800-2 200 m)<br />
Forets submontagnardes 800-2 200 m (n° 117)<br />
Etage de basse et moy<strong>en</strong>ne altitude (0 - 800 m)<br />
District atlantique biajre<strong>en</strong><br />
Forets atlantiques biafre<strong>en</strong>nes a Caesalpiniaceae (nO 228)<br />
Forets atJantiques atIantiques biafre<strong>en</strong>nes it a Caesalpiniaceae <strong>en</strong>core abondantes, avec Saccoglottis gabon<strong>en</strong>sis et autres indices<br />
Iittoraux (nO 231)<br />
Forets mixtes, toujours vertes atlantiques et semi-caducifoliees, avec predominance d'elem<strong>en</strong>ts de forets toujours<br />
vertes atlantiques (nO 233)<br />
Facies de degradation prononcee des forets toujours vertes (n° 234 = n° 251)<br />
District atlantique littoral<br />
Forets atlantiques littorales a Caesalpiniaceae relativem<strong>en</strong>t rares, avec Saccoglottis gabon<strong>en</strong>sis (nO 247)<br />
Facies de degradation prononcee des forets toujours vertes (n° 251 = n° 234)<br />
The majority <strong>of</strong> <strong>the</strong> TCP research area lies within <strong>the</strong> Atlantic Biafran forests zone rich in<br />
Caesa/piniaceae (n° 228 in Letouzey, 1985). The vegetation can be characterized as evergre<strong>en</strong><br />
tropical moist forest with many species <strong>of</strong> <strong>the</strong> Caesalpiniaceae family. Of <strong>the</strong> total <strong>of</strong> 130-140<br />
species <strong>of</strong> shrubs and trees <strong>of</strong> this family recorded in Cameroon, more than half appear to be<br />
conc<strong>en</strong>trated in <strong>the</strong> Biafran Atlantic forests. Many Caesa/piniaceae species are gregariously<br />
distributed. The range in altitude <strong>of</strong> this forest type is (100) 200-500 m as!.<br />
The mixed evergre<strong>en</strong> Atlantic and semi-deciduous forest (n° 233) is restricted to <strong>the</strong> mountainous<br />
region in <strong>the</strong> East <strong>of</strong> <strong>the</strong> TCP research area. This vegetation type is a transition betwe<strong>en</strong> <strong>the</strong><br />
evergre<strong>en</strong> forests <strong>of</strong> <strong>the</strong> Biafran district and <strong>the</strong> semi-deciduous forest <strong>of</strong> <strong>the</strong> C<strong>en</strong>tral/Ori<strong>en</strong>tal<br />
Atlantic district. Characteristic families are Caesa/piniaceae, Sterculiaceae and Ulmaceae. The<br />
zone is confined to altitudes higher than 500 m as!.<br />
57
and <strong>the</strong> vegetation resembles 'cloud forests' with many epiphytes and a canopy that reaches only<br />
20-30 m. Ano<strong>the</strong>r striking characteristic is <strong>the</strong> near complete abs<strong>en</strong>ce <strong>of</strong> members <strong>of</strong> <strong>the</strong><br />
Caesalpiniaceae family, apart from typical mountain species like Monopetalanthus spp.,<br />
Plagiosiphon sp., Hym<strong>en</strong>ostegia sp. and Anthonotha cf. cladantha.<br />
Along <strong>the</strong> main access routes and in <strong>the</strong> vicinity <strong>of</strong> <strong>the</strong> larger villages strongly degraded remnants<br />
<strong>of</strong> evergre<strong>en</strong> forests (nOS 234 and 251) are found. In g<strong>en</strong>eral <strong>the</strong> degraded vegetation is<br />
characterized by <strong>the</strong> abs<strong>en</strong>ce <strong>of</strong> a tree layer, except for a few residual forest trees, and <strong>the</strong><br />
abundance <strong>of</strong> pioneer species such as Haumania danckelmanniana, Harungana madagascari<strong>en</strong>sis,<br />
Megaphrynium macrostachyum, Xylopia aethiopica, and Musanga cecropioides. According to<br />
Letouzey's map, <strong>the</strong> degraded areas are not differ<strong>en</strong>tiated by phytogeographical zone, i.e. littoral<br />
Atlantic district and Biafran Atlantic district.<br />
6.2 BOTANICAL DIVERSITY<br />
A total surface <strong>of</strong> approximately 20 ha was inv<strong>en</strong>toried during <strong>the</strong> pres<strong>en</strong>t vegetation survey. A<br />
total <strong>of</strong> 490 taxa have be<strong>en</strong> id<strong>en</strong>tified to <strong>the</strong> species level, be longing to 76 families. The most<br />
species rich families are: Euphorbiaceae (47 species), Caesalpiniaceae (43 species), Rubiaceae (29<br />
species) and Annonaceae (18 species). All id<strong>en</strong>tified species are listed in Annex Va.<br />
Id<strong>en</strong>tification in <strong>the</strong> field proved to distinguish some 530 'species', including several (small)<br />
0" /. .groups ,groups <strong>of</strong> botanical species. The basis for <strong>the</strong> vegetation classification is <strong>the</strong> field id<strong>en</strong>tification.<br />
The number <strong>of</strong> plant species <strong>en</strong>countered will surely increase with time wh<strong>en</strong> collecting is<br />
continued and <strong>the</strong> skill <strong>of</strong> <strong>the</strong> collectors grows. It is <strong>the</strong>refore difficult to indicate <strong>the</strong> plant diversity<br />
<strong>of</strong> <strong>the</strong> TCP area on <strong>the</strong> basis <strong>of</strong> <strong>the</strong>se results. A large and species rich area like ours, needs<br />
int<strong>en</strong>sive collection to properly reveal species number, rarity and <strong>en</strong>demics. The second phase <strong>of</strong><br />
<strong>the</strong> Lul project will give some indications in this respect, while <strong>the</strong> forthcoming Ecoll project is<br />
will be properly equipped to address <strong>the</strong> question <strong>of</strong> plant diversity.<br />
6.3 VEGETATION CLASSIFICATION<br />
The vegetation <strong>of</strong> <strong>the</strong> TCP research area can be divided into sev<strong>en</strong> distinct plant communities.<br />
Information ga<strong>the</strong>red during <strong>the</strong> reconnaissance vegetation survey clearly indicates that within<br />
each <strong>of</strong> <strong>the</strong> plant communities two or three variants can be distinguished.<br />
A d<strong>en</strong>drogram repres<strong>en</strong>ting <strong>the</strong> hierarchical vegetation classification is pres<strong>en</strong>ted in Figure 6.2. The<br />
hierarchy is based on similarities in species composition as giv<strong>en</strong> by <strong>the</strong> TWINSPAN analysis. A<br />
division at a high level coincides with major differ<strong>en</strong>ces in floristic composition. A division at a<br />
lower level coincides with more subtle differ<strong>en</strong>ces in species composition.<br />
Not surprisingly, a distinction is made on <strong>the</strong> highest level betwe<strong>en</strong> <strong>the</strong> floristic composition <strong>of</strong><br />
forest and shrub land. Of more interest is <strong>the</strong> distinction at <strong>the</strong> second level betwe<strong>en</strong> <strong>the</strong> forest at<br />
low altitudes and those on high altitudes. The flora <strong>of</strong> mountain forests (> 700 m above sea level)<br />
proves to deviate strongly from that <strong>of</strong> lowland forests, appar<strong>en</strong>tly regardless <strong>of</strong> soil type and<br />
former disturbances.<br />
In Table 6.2 an overview <strong>of</strong> <strong>the</strong> vegetation types is pres<strong>en</strong>ted. Each community is named after a<br />
characteristic combination <strong>of</strong> occurring g<strong>en</strong>era.<br />
59
Plant communities communities<br />
Ha<br />
lIb<br />
lIe <strong>II</strong>I IV ·V··<br />
Differ<strong>en</strong>tiating Maran<strong>the</strong>s -<br />
Podococcus<br />
Strombosia -Diospyros - Diospyros" " Carapa- Xylopia- Xylopia- Macaranga-<br />
Macaranga-<br />
species:<br />
AnisophyUea<br />
- PolyalthiaPolyalthia Polyalthia Polyalthia<br />
community<br />
community<br />
community<br />
Polyalthia . MitragynaMusangaChroni.OI!i<strong>en</strong>a<br />
Mitragyna Musanga Chroni.ol!i<strong>en</strong>a<br />
community<br />
• commullity commUllity ..• , community ,. cOmmunity<br />
Elaeis guine<strong>en</strong>sis<br />
+<br />
<strong>II</strong>I ... 11 <strong>II</strong>I<br />
Mitragyna stipulosa<br />
Carapa 'species I'<br />
<strong>II</strong>I<br />
Trichillia heudelotii<br />
+<br />
+<br />
<strong>II</strong>I<br />
Xylopia 'group l'<br />
+<br />
11<br />
<strong>II</strong><br />
IV<br />
11 <strong>II</strong><br />
Fagara macrophylla +<br />
11<br />
11 11 <strong>II</strong> 11 IV<br />
<strong>II</strong>I<br />
Thaumantoc. 'group l'<br />
I<br />
IV IV<br />
11 <strong>II</strong><br />
Eribroma 'group l'<br />
+<br />
.IlI + <strong>II</strong> <strong>II</strong><br />
Terminalia superba<br />
11 +<br />
11<br />
Myrianthus arboreus<br />
n<br />
<strong>II</strong><br />
Musanga cecropioides +<br />
+<br />
<strong>II</strong> 11<br />
IV<br />
Funtumia elastica<br />
<strong>II</strong>I<br />
Rauvolfia macrophylla<br />
+<br />
U'<br />
Macaranga 'group l'<br />
Chromola<strong>en</strong>a odorata<br />
Milicia excelsa<br />
Rauvolfia vomitoria<br />
Ceiba p<strong>en</strong>tandra<br />
Trifolium 'species l'<br />
Anchom. 'species l'<br />
Manihot escul<strong>en</strong>ta<br />
+<br />
<strong>II</strong> <strong>II</strong><br />
+<br />
+<br />
+ +<br />
+<br />
IV····· IV···'··<br />
IV·· IY'<br />
Ill"· n.I.·.· ..<br />
(<strong>II</strong>1) (Ill) .. '.<br />
m· In<br />
(!HY UIl)·· .. i ••.<br />
Frequ<strong>en</strong>cy classes: classes: . . = abs<strong>en</strong>t; r = occurring occurring once; + + = pres<strong>en</strong>t in 1-9% <strong>of</strong> <strong>the</strong> releves; releves; 1= 1= 10-19%; 11 <strong>II</strong> = 20-39%; <strong>II</strong>I = 40-59%; IV =<br />
60-79% and V = 80-100% () = cultivated.<br />
6.4 PLANT COMMUNITIES<br />
In this section <strong>the</strong> floristic composition, <strong>the</strong> physiognomy and <strong>the</strong> distribution <strong>of</strong> <strong>the</strong> sev<strong>en</strong> plant<br />
communities are described. A A t<strong>en</strong>tative comparison comparison with <strong>the</strong> vegetation types described described by<br />
Letouzey (1968, 1985) and UNESCO (1981), and an ecological interpretation is included.<br />
6.4.1 Marantbes Marantbes - Anisopbyllea community (I)<br />
The Maran<strong>the</strong>s-Anisophyllea community includes submontane primary and old secondary forests;<br />
its distribution within <strong>the</strong> TCP research area is restricted to hill and mountain tops surpassing 700<br />
m m asl. asl. Differ<strong>en</strong>tiating species species <strong>of</strong> this community are Drypetes Drypetes 'group 1', Anisophyllea polyneura,<br />
Maran<strong>the</strong>s glabra, Scorodophloeus z<strong>en</strong>keri, Gambeya 'group l' Cola atti<strong>en</strong>sis, Garcinia lucida<br />
and Diospyros hoyleana.<br />
In g<strong>en</strong>eral, <strong>the</strong> physiognomy <strong>of</strong> this forest is characterized by <strong>the</strong> abs<strong>en</strong>ce <strong>of</strong> emerg<strong>en</strong>ts. Three<br />
structural structural layers can be be distinguished. The tree layer forms an an irregular canopy at a height <strong>of</strong> 15-20<br />
m, occasionally reaching 35 m, with an external foliage cover cover <strong>of</strong> 70-80 %. The canopy is is <strong>of</strong>t<strong>en</strong><br />
climber infested and <strong>the</strong> pres<strong>en</strong>ce <strong>of</strong> epiphytic mosses is is characteristic. The broad-leaved broad-leaved trees, trees,<br />
probable both evergre<strong>en</strong> and deciduous, are branched at low heights and may have a a crooked form.<br />
Stilt roots are common. Scorodophloeus z<strong>en</strong>keri, Carapa 'group 1', Monopethalanthus spp.,<br />
Uapaca guine<strong>en</strong>sis, Santira trim era, Allanblackia kisonghi, Anisophyllea polyneura, Baphia<br />
lepitobotryx, Coelycaryon preussi, Maran<strong>the</strong>s glabra and Tetraberlinia bifoliata are relatively<br />
common in <strong>the</strong> canopy. canopy. In some some localities palms palms (Raphia (Raphia 'species 1 ') are pres<strong>en</strong>t. The shrub layer<br />
(3-7 (3-7 m), sometimes replacing <strong>the</strong> tree tree layer layer as canopy, varies from closed to very op<strong>en</strong>. The shrub<br />
layer layer is mainly composed <strong>of</strong> saplings <strong>of</strong> forest trees. Only a few shrub species are pres<strong>en</strong>t.<br />
62<br />
IV<br />
·V·'
Climbers such as Haumania danckelmanniana and Ancistrophyllium secundijlorum are frequ<strong>en</strong>tly<br />
found. Treculia obovoides, Scorodophloeus z<strong>en</strong>keri, Baphia lepitobotryx, Garcinia lucida,<br />
Garcinia mannii, Mammea africana and Drypetes 'group I '. are <strong>the</strong> most common species <strong>of</strong> <strong>the</strong><br />
shrub layer. The herb layer is closed and may reach a height <strong>of</strong> one meter. This layer is dominated<br />
ei<strong>the</strong>r by seedlings <strong>of</strong> forest trees or by herbs. Diospyros hoyleana, Scaphopetalum thonneri,<br />
Halopegia spp, Mapania amplivaginata and Palisotha mannii are frequ<strong>en</strong>tly found.<br />
The forests <strong>of</strong> this type appear to be highly dynamic. Many traces <strong>of</strong> uprooted and brok<strong>en</strong> trees are<br />
found. The gaps thus created are <strong>of</strong>t<strong>en</strong> infested by climbers that may reach down to <strong>the</strong> herb layer.<br />
Pioneer species like Musanga cecropioides are found in <strong>the</strong> larger gaps. Possible explanations for<br />
<strong>the</strong> dynamic nature <strong>of</strong> this vegetation are exposure to wind and instable steep slopes, <strong>of</strong>t<strong>en</strong> with<br />
rock outcrops.<br />
The submontane forest <strong>of</strong> <strong>the</strong> Maran<strong>the</strong>s - Anisophyllea community covers major parts <strong>of</strong> <strong>the</strong><br />
Bingalanda mountain range in <strong>the</strong> sou<strong>the</strong>astern part <strong>of</strong> <strong>the</strong> TCP area. The predominating landforms<br />
are mountains and isolated hills. The soils <strong>of</strong> <strong>the</strong>se areas belong to <strong>the</strong> Nyangong type, i.e. very<br />
clayey soils with 40 to 80% clay in <strong>the</strong> B horizon.<br />
The structure <strong>of</strong> this forest type resembles 'cloud forests'. As <strong>the</strong> elevation surpasses <strong>the</strong> average<br />
height <strong>of</strong> <strong>the</strong> cloud layer, <strong>the</strong> vegetation is regularly <strong>en</strong>gulfed in mist and drizzle (Hommel, 1985).<br />
A characteristic growth form <strong>of</strong> such forests is beard moss. In <strong>the</strong> UNESCO classification <strong>of</strong><br />
vegetation (1981), this vegetation can be typified as Tropical ombrophilous submontane forest.<br />
'The distribution <strong>of</strong> this community coincides with <strong>the</strong> forest types n° 117, n° 233 and partly with<br />
n° 228 <strong>of</strong> <strong>the</strong> phytogeographic map <strong>of</strong> Letouzey (1985, see Figure 6.1). Structurally, it resembles<br />
Letouzey's Forets submontagnardes (nO 117) although species composition is distinctly differ<strong>en</strong>t.<br />
Quite a number <strong>of</strong> species characteristic for <strong>the</strong> Maran<strong>the</strong>s - Anisophyllea community are typical<br />
for Letouzey's Semi-deciduous forest with Sterculiaceae and Ulmaceae (nOS 160 and 161). Also<br />
many repres<strong>en</strong>tatives <strong>of</strong> <strong>the</strong> Atlantic Biafran forest with Caesalpiniaceae (n° 228) are found. The<br />
Maran<strong>the</strong>s - Anisophyllea community appar<strong>en</strong>tly is a transitional vegetation betwe<strong>en</strong> <strong>the</strong> moist<br />
Atlantic forest zone and <strong>the</strong> drier Guineo-Congolian semi-deciduous forest zone.<br />
Mbatchou (1995) studied <strong>the</strong> vegetation <strong>of</strong> <strong>the</strong> proposed Etinde Rainforest reserve on <strong>the</strong> slopes<br />
<strong>of</strong>Mt Cameroon (4095 m asl) in <strong>the</strong> South-West Province <strong>of</strong>Cameroon.<br />
The submontane forest described by Mbatchou is divided in closed canopy submontane forest,<br />
discontinuous canopy submontane forest and submontane scrub. It is found betwe<strong>en</strong> 800 and 1,700<br />
m as!.. The submontane forests appears to be <strong>the</strong> transition betwe<strong>en</strong> <strong>the</strong> lowland forest and <strong>the</strong><br />
lower montane forest, and <strong>the</strong> species composition is a mixture <strong>of</strong> Guineo-Congolian and<br />
afromontane species. In structure and floristic composition, <strong>the</strong> Maran<strong>the</strong>s-Anisophyllea<br />
community resembles <strong>the</strong> closed canopy submontane forest <strong>of</strong> Mount Cameroon, although it is<br />
found in <strong>the</strong> TCP research area at much lower altitudes. The 'telescope-effect', i.e. <strong>the</strong> vegetation<br />
<strong>of</strong> <strong>the</strong> highest summits in a giv<strong>en</strong> area more or less imitates <strong>the</strong> physiognomy and species<br />
composition <strong>of</strong> forest types g<strong>en</strong>erally bound to far higher altitudes elsewhere (Hommel, 1987),<br />
could possibly be an explanation for <strong>the</strong> differ<strong>en</strong>ce in altitude range.<br />
63
6.4.2 Podococcus Podococcus - Polyalthia Polyalthia community (lIa)<br />
The Podococcus - Polyalthia community is a primary and old secondary lowland forest type; it is<br />
found at at altitudes betwe<strong>en</strong> 500 and 700 m as!. Differ<strong>en</strong>tiating species are are Hym<strong>en</strong>ostegia ajzeilii,<br />
Podococcus barteri, Crotonogyne preussii, Tabernaemontana 'species 1', Culcasia dinklagei, dinklagei,<br />
Duboscia macrocarpa and Petersianthus africana.<br />
At least four principal strata characterize <strong>the</strong> physiognomy <strong>of</strong> <strong>the</strong> Podococcus - Polyalthia<br />
community, although <strong>the</strong>ir boundaries are <strong>of</strong>t<strong>en</strong> difficult to establish. establish. Large trees, <strong>of</strong>t<strong>en</strong> surpassing<br />
55 meters in height, form <strong>the</strong> op<strong>en</strong> (20 -30% cover) emerg<strong>en</strong>t layer. Klainedoxa microphylla and<br />
Monopethalanthus spp. frequ<strong>en</strong>tly dominate this stratum. The tree layer forms a canopy at 25 to<br />
40 meters. The external foliage coverage is 60-80 %. Large trees are <strong>the</strong> most common growth<br />
form and lianas appear to be be restricted restricted to <strong>the</strong> canopy and larger gaps. In In g<strong>en</strong>eral <strong>the</strong> trees have a<br />
smooth bark and only few have buttresses surpassing one one meter in height. The most common<br />
species are are Pycnanthus angol<strong>en</strong>sis, Uapaca guine<strong>en</strong>sis, Strombosia 'group 1', Dichostemma<br />
glaucesc<strong>en</strong>s, Plagiostyles africana, Santira trim era, era, Alstonia cong<strong>en</strong>sis, Hym<strong>en</strong>ostegia Hym<strong>en</strong>ostegia ajzeilii,<br />
Desbord<strong>en</strong>sia glaucesc<strong>en</strong>s and Scyphocephalium mannii. The shrub layer is relatively op<strong>en</strong>,<br />
covering 40-60% and betwe<strong>en</strong> two and t<strong>en</strong> meters high. Shrubs and saplings <strong>of</strong> forest trees are<br />
most common. Palms (Raphia 'species 1 ' and Podococcus barteri) are frequ<strong>en</strong>tly pres<strong>en</strong>t but never<br />
dominate. Frequ<strong>en</strong>tly found species <strong>of</strong> <strong>the</strong> shrub layer are Ptycopetalum petiolanum, Polyalthia<br />
suaveol<strong>en</strong>s, Scaphopetalum thonneri, thonneri, Scaphopetalum blackii, Plagiostyles africana, africana, Voacanga<br />
'group 'group 1', 1', Dialium 'group 1', C<strong>of</strong>fea 'group 1 l' ' and Grossera 'group 1'. The herb layer is relatively<br />
op<strong>en</strong>, covering 40-50%, 40-50%, and <strong>of</strong>t<strong>en</strong> low. Broad leaved herbs, seedlings <strong>of</strong> trees, palms and lianas<br />
are <strong>the</strong> major compon<strong>en</strong>ts. Frequ<strong>en</strong>tly occurring species include Haumania danckelmannia,<br />
Palisota mannii, Halopegia 'group 1', Calamus deeratus, Scaphopetalum thonneri, Rektophyllium<br />
'group 1', Cercestis ivor<strong>en</strong>sis, Trachyprhrynium braunianum and Podococcus barteri.<br />
The Podococcus - Polyalthia community is found at altitudes altitudes betwe<strong>en</strong> 500 500 and 700 m m as!. as!. It It is is<br />
found found mainly in <strong>the</strong> sou<strong>the</strong>astern zone <strong>of</strong> <strong>the</strong> TCP research area covering <strong>the</strong> slopes <strong>of</strong> <strong>the</strong><br />
Bingalanda mountain range. The soils soils are are mostly <strong>of</strong> <strong>the</strong> Nyangong type, i.e. very clayey soils with<br />
40 to 80% clay in <strong>the</strong> B horizon. Land forms <strong>en</strong>countered are, in desc<strong>en</strong>ding order <strong>of</strong> importance:<br />
hilly uplands, complexes <strong>of</strong> hills, rolling uplands and isolated hills.<br />
According to <strong>the</strong> UNESCO classification (1981) this community is a Tropical ombrophilous<br />
lowland forest. The distribution <strong>of</strong> Podococcus - Polyalthia community in <strong>the</strong> TCP area coincides<br />
with <strong>the</strong> eastern part <strong>of</strong> Letouzey's Atlantic Biafran forest with Caesalpiniaceae (no. 228) <strong>of</strong> which<br />
<strong>the</strong> physiognomy and species composition composition indeed resemble <strong>the</strong> Podococcus - Polyalthia<br />
community.<br />
6.4.3 Strombosia Strombosia - Polyalthia community (lib)<br />
The primary and old secondary lowland forest <strong>of</strong> <strong>the</strong> Strombosia - Polyalthia community is found<br />
betwe<strong>en</strong> 350 and 500 m as!. as!. On <strong>the</strong> <strong>the</strong> basis <strong>of</strong> <strong>the</strong> <strong>the</strong> pres<strong>en</strong>t vegetation vegetation survey only two (weakly) (weakly)<br />
differ<strong>en</strong>tiating differ<strong>en</strong>tiating species have have be<strong>en</strong> be<strong>en</strong> id<strong>en</strong>tified, id<strong>en</strong>tified, i.e. Grewia coriacea coriacea and Saccoglottis gabon<strong>en</strong>sis. The<br />
community is intermediate in both altitude and floristic composition betwe<strong>en</strong> <strong>the</strong> two o<strong>the</strong>r primary<br />
to old secondary lowland forest communities: <strong>the</strong> Podococcus - Polyalthia community (Ha) and<br />
<strong>the</strong> Diospyros - Polyalthia community (<strong>II</strong>c). (<strong>II</strong>c).<br />
The physiognomy physiognomy <strong>of</strong> <strong>the</strong> Strombosia - Polyalthia community is similar to that that <strong>of</strong> <strong>of</strong> <strong>the</strong> Podococcus<br />
Podococcus<br />
Polyalthia community. The complex structure <strong>of</strong> <strong>the</strong> forest has has four principal strata, including an<br />
emerg<strong>en</strong>t layer, a tree layer, a shrub shrub layer and a herb layer. The height <strong>of</strong> <strong>the</strong> differ<strong>en</strong>t strata varies<br />
and <strong>the</strong> boundaries are <strong>of</strong>t<strong>en</strong> difficult to establish. The emerg<strong>en</strong>t layer is op<strong>en</strong> (external foliage<br />
cover < 20%) and reaches a height <strong>of</strong> 45-55 meters. The floristic composition composition is heterog<strong>en</strong>eous<br />
64
although Erythrophleum ivor<strong>en</strong>sis appears to be <strong>the</strong> most common species. The external foliage<br />
cover <strong>of</strong> <strong>the</strong> tree layer is g<strong>en</strong>erally 60 - 70 %. The tree layer is found at <strong>the</strong> height <strong>of</strong> 25 to 35<br />
meters. Broad-leaved evergre<strong>en</strong> trees are <strong>the</strong> dominant growth form Lianas are relatively rare and<br />
no palms have be<strong>en</strong> observed. The most common species are Plagiostyles africana, Coula edulis,<br />
Staudtia kamerun<strong>en</strong>sis, Treculia obovoides, Coelecaryon preussii, Polyalthia suaveol<strong>en</strong>s,<br />
Strombosia pistulata and Erythrophleum ivor<strong>en</strong>sis. The shrub layer is d<strong>en</strong>se (70-80%) and variable<br />
in height. In g<strong>en</strong>eral it reaches from three to eight meters. It consists mainly <strong>of</strong> saplings <strong>of</strong> trees<br />
and shrubs. Lianas are scarce. The floristic composition <strong>of</strong> <strong>the</strong> shrub layer is heterog<strong>en</strong>ous. The<br />
most frequ<strong>en</strong>tly observed species are Treculia obovoides, Scaphopetaleum blackii, Ptycopetalum<br />
petiolanum, Carapa 'group 1', Dialium 'group 1', Grossera 'group 1', Polyalthia suaveol<strong>en</strong>s,<br />
Strombosia pistulata, Coelocaryon preussii, Staudtia kamerun<strong>en</strong>sis and Calpocalyx dinklagei. The<br />
herb layer is relatively op<strong>en</strong> (40%) and is in g<strong>en</strong>eral 0.4 to 0.7 meters high. Broad leaved herbs<br />
(e.g. Rektophyllium 'group 1', Palisota mannii, Halopegia 'group 1', Cercestis ivor<strong>en</strong>sis,<br />
Stylochiton z<strong>en</strong>keri), seedlings <strong>of</strong> shrubs and trees (e.g. P<strong>en</strong>taclethra macrophylla, Treculia<br />
obovoides, Dialium 'group 1', Scaphopetaleum blackii, Scaphopetalum thonneri) and thorny lianas<br />
(e.g. Calamus deeratus, Haumannia danckelmanniana) are <strong>the</strong> most important compon<strong>en</strong>ts.<br />
The Strombosia - Polyalthia community is found in <strong>the</strong> c<strong>en</strong>tral part <strong>of</strong> <strong>the</strong> TCP area forming a band<br />
<strong>of</strong> 10 to 15 km wide with a g<strong>en</strong>eral southwest to nor<strong>the</strong>ast direction. The altitude range is 350 to<br />
500 m as!. Rolling and hilly uplands are <strong>the</strong> most important land forms in this zone. The soils are<br />
classified as 'Ebom', i.e. clayey soils with 30 to 60% clay in <strong>the</strong> B horizon.<br />
According to <strong>the</strong> UNESCO classification (1981) this community is a tropical ombrophilous<br />
. lowland forest. The distribution <strong>of</strong> <strong>the</strong> Strombosia - Polyalthia community is strictly confined to<br />
Letouzey's Atlantic Biafran forest with Caesalpiniaceae (n° 228, 1985, see Figure 6.1). Letouzey's<br />
description <strong>of</strong> <strong>the</strong> physiognomy and floristic composition <strong>of</strong> <strong>the</strong> Atlantic Biafran forest with<br />
Caesalpiniaceae corresponds with <strong>the</strong> Strombosia - Polyalthia community.<br />
6.4.4 Diospyros - Polyalthia community (lIe)<br />
The Diospyros - Polyalthia community is a primary to old secondary forest <strong>of</strong> altitudes below 350<br />
m as!. Differ<strong>en</strong>tiating species <strong>of</strong> this community are Diospyros suaveol<strong>en</strong>s, Draceana 'group l'<br />
and Picralima nitida.<br />
The physiognomy <strong>of</strong> <strong>the</strong> vegetation again is very similar to <strong>the</strong> structure <strong>of</strong> <strong>the</strong> o<strong>the</strong>r two<br />
communities <strong>of</strong> <strong>the</strong> Polyalthia community group. The forest structure is characterized by four<br />
principal strata. The emerg<strong>en</strong>t stratum is very irregular and its coverage varies betwe<strong>en</strong> 0 and 30%.<br />
The average height <strong>of</strong> this layer is 45 meters. Among <strong>the</strong> most common species are Desbord<strong>en</strong>sia<br />
glaucesc<strong>en</strong>s, Klain<strong>en</strong>doxa gabon<strong>en</strong>sis and Distamonanthus b<strong>en</strong>thamianus. The tree layer is d<strong>en</strong>se<br />
(70-80%) and is, in g<strong>en</strong>eral, 20 to 35 meters in height. Trees are <strong>the</strong> sole important growth form<br />
in <strong>the</strong> canopy, except for <strong>the</strong> numerous gaps which are infested with thorny lianas. The most<br />
frequ<strong>en</strong>tly occurring species <strong>of</strong> <strong>the</strong> tree layer are Plagiostyles africana, Coelocaryon preussii,<br />
Staudtia kamerun<strong>en</strong>sis, Pycnanthus angol<strong>en</strong>sis, Desbord<strong>en</strong>sia glaucesc<strong>en</strong>s, Eribroma 'group 1',<br />
Hylod<strong>en</strong>dron 'group l' and Distamonanthus b<strong>en</strong>thamianus. The shrub layer is relatively op<strong>en</strong><br />
where <strong>the</strong> canopy is closed, but can be very d<strong>en</strong>se in <strong>the</strong> vicinity <strong>of</strong> gaps. Its height is variable but<br />
g<strong>en</strong>erally ranges from three to eight meters. Shrubs, small trees and saplings are <strong>the</strong> most important<br />
compon<strong>en</strong>ts. The most common species are Rinorea kamerun<strong>en</strong>sis, Diospyros suaveol<strong>en</strong>s,<br />
Calpocalyx dinklagei, Scaphopetaleum blackii, Anthonotha macrophylla, Grossera 'group 1',<br />
Ptycopetaleum petiolanum, Polyalthia suaveol<strong>en</strong>s and Tabernaemontana crassa. The herb layer<br />
is relatively op<strong>en</strong> (40%), again with <strong>the</strong> exception <strong>of</strong> gaps where it is very d<strong>en</strong>se. The average<br />
height is 0.5 meters and it consists <strong>of</strong> broad leaved herbs, lianas, ferns, grasses and tree seedlings.<br />
65
Most common species in <strong>the</strong> herb layer layer are are Haumannia danckelmanniana, Rektophyllium 'group<br />
I', Gauduella spp., Cercestis ivor<strong>en</strong>sis, Stylochiton z<strong>en</strong>keri and Palisota ambigua.<br />
The Diospyros - Polyalthia community is found at low altitudes « 3 50 m asl) in <strong>the</strong> northwest <strong>of</strong><br />
<strong>the</strong> TCP area. The most important land forms are dissected plains, rolling uplands and hilly<br />
uplands. The soils in <strong>the</strong>se regions are classified as 'Ebimimbang' type, i.e. moderately well<br />
drained soils with sandy top soils and less than 40% clay in <strong>the</strong> sub soil.<br />
The dissected plains in <strong>the</strong> northwest are relatively int<strong>en</strong>sively used for shifting cultivation<br />
practices. Moreover, <strong>the</strong> area has be<strong>en</strong> repeatedly logged. As a result <strong>the</strong> vegetation in this area is<br />
a mosaic <strong>of</strong> agricultural fields and more or less secondary forest and only small patches <strong>of</strong><br />
relatively undisturbed forest <strong>of</strong> <strong>the</strong> Diospyros - Polyalthia community.<br />
According to <strong>the</strong> UNESCO classification (1981) this community is a tropical ombrophilous<br />
lowland forest. The distribution <strong>of</strong> <strong>the</strong> Diospyros - Polyalthia community within <strong>the</strong> TCP area<br />
includes <strong>the</strong> area designated by Letouzey (1985, see Figure 6.1) for <strong>the</strong> Biafran Atlantic forest rich rich<br />
in Caesalpiniaceae (n° 228) and Biafran Atlantic forest with Caesalpiniaceae still abundant (n°<br />
231). Although <strong>the</strong> physiognomy is similar, <strong>the</strong> species composition <strong>of</strong> <strong>the</strong> tree and shrub layer <strong>of</strong><br />
<strong>the</strong> Diospyros - Polyalthia community community is quite differ<strong>en</strong>t from <strong>the</strong> two Letouzey types. In fact, fact, none<br />
<strong>of</strong> <strong>the</strong> Letouzey forest types is similar to this community nei<strong>the</strong>r in physiognomy nor in species<br />
composition. A possible explanation could be that <strong>the</strong> floristic composition <strong>of</strong> <strong>the</strong> forest has<br />
changed quite rec<strong>en</strong>tly due to repetitive logging operations, while Letouzey bases his classification<br />
on more or less primary vegetation.<br />
6.4.5 Carapa - Mitragyna community (Ill)<br />
The Carapa - Mitragyna community is a swamp forest. Differ<strong>en</strong>tiating species for this community<br />
are Mitragyna stipulosa, Carapa 'species I', Trichillia heudelotii, Diospyros Diospyros preussii Cya<strong>the</strong>a Cya<strong>the</strong>a<br />
'species I' and Curcuma longa.<br />
The Carapa - Mitragyna community has three principal structural layers. The tree layer forms an<br />
op<strong>en</strong> (60% (60% cover) canopy at 35-40 m. Lianas like Ancistrophrynium secundiflorum, Haumania<br />
danckelmaniana and Calamus deeratus are abundant. The trees are <strong>of</strong>t<strong>en</strong> <strong>of</strong>t<strong>en</strong> stilt rooted, rooted, crooked and and<br />
branching at low heights. Mosses and epiphytes are found found all along <strong>the</strong> stems. Common species species<br />
<strong>of</strong> <strong>the</strong> tree layer are Coelycaryon preussi, Mitragyna stipulosa, Strombosia 'group 1', Uapaca<br />
guine<strong>en</strong>sis, Uapaca v<strong>en</strong>hussii, Carapa 'species I' ('<strong>en</strong>gang osoe') and Raphia 'species 2'. The<br />
shrub layer (2-7 m) is <strong>of</strong>t<strong>en</strong> op<strong>en</strong> and is composed <strong>of</strong> saplings, lianas, palms, shrubs and tree ferns.<br />
Anthonotha macrophylla, Elaeis guine<strong>en</strong>sis, Carapa 'species 1', Diospyros preussii, Trichillia<br />
heudelotii and Raphia 'species 2' 2' are <strong>the</strong> most common species. In some localities <strong>the</strong> abundance<br />
<strong>of</strong> Draceana spp. is remarkable. The distribution <strong>of</strong> herbaceous plants is very irregular. Very d<strong>en</strong>se<br />
patches patches alternate with with stretches stretches with with virtually no terrestrial terrestrial plants. plants. Palisotha mannii, mannii, Ha/opegia<br />
azurea and Sarcophrynium prionogonium grow gregariously and <strong>of</strong>t<strong>en</strong> dominate <strong>the</strong> herb layer.<br />
O<strong>the</strong>r frequ<strong>en</strong>tly occurring species are are Curcuma longa, Stylochiton z<strong>en</strong>keri, Draceana phrynioides<br />
and Rektophylium m irabiles.<br />
The community is found in valley bottoms and along creeks and rivers throughout <strong>the</strong> TCP<br />
research area. It covers fair surfaces <strong>of</strong> <strong>the</strong> dissected plains <strong>of</strong><strong>the</strong> western part <strong>of</strong> <strong>the</strong> study area.<br />
Forests <strong>of</strong> <strong>the</strong> Carapa -- Mitragyna community are found found betwe<strong>en</strong> 40-700 m m asl. asl. The vegetation vegetation<br />
is restricted to <strong>the</strong> soil type 'valley bottoms', which are poorly to imperfectly drained soils which<br />
t<strong>en</strong>d to to be shallow and having a thin organic layer.<br />
66
The vegetation <strong>of</strong> this community group are broad-leaved tropical ombrophilous swamp forests<br />
and broad-leaved tropical ombrophilous alluvial forests (UNESCO, 1981). Due to <strong>the</strong> small scale<br />
<strong>of</strong> Letouzey' Letouzey's s phytogeographic map, i.e. 1:500,000, I :500,000, <strong>the</strong> small areas covered by swamp vegetation<br />
have not be<strong>en</strong> accounted for individually. They appear as complexes with <strong>the</strong> surrounding forest<br />
types.<br />
6.4.6 Xylopia - Musanga community (IV)<br />
The Xylopia - Musanga community is a young secondary forest. Differ<strong>en</strong>tiating species <strong>of</strong> this<br />
community are Xylopia 'group 1', Fagara macrophylla, Palisota ambigua, Thaumantococcus<br />
'group 1', Megaphrynium secundiflorum and Ancistrophyllum 'group 1'.<br />
In g<strong>en</strong>eral, <strong>the</strong> vegetation consists <strong>of</strong> three distinct strata: tree, shrub and herb layer. Oft<strong>en</strong> relics<br />
<strong>of</strong> <strong>the</strong> undisturbed forest are pres<strong>en</strong>ts. In g<strong>en</strong>eral <strong>the</strong> external foliage cover <strong>of</strong> <strong>the</strong>se emerg<strong>en</strong>ts is<br />
less than t<strong>en</strong> perc<strong>en</strong>t. The tree layer is op<strong>en</strong> (40-50%) and is only 15-25 m high. Dominant growth<br />
forms are evergre<strong>en</strong> broad-leaved trees and palms. The most common species are Musanga<br />
cecropioides, Pycnanthus angol<strong>en</strong>sis, Coelocaryum preussii, Funtumia elastica, Xylopia 'group<br />
I', Tabernaemontana crassa, Rauvolfia macrophylla and Ricinod<strong>en</strong>dron heudelotti. O<strong>the</strong>r<br />
frequ<strong>en</strong>tly occurring species are Fagara macrophylla, Vitex grandifolia and Macaranga 'group<br />
I'. The shrub layer is 2-7 m high and <strong>of</strong>t<strong>en</strong> merges into <strong>the</strong> tree layer. It is closed and infested with<br />
thorny Iianas such as Ancistrophrynium secundiflorum and Haumania danckelmanniana. The trees<br />
in this layer <strong>of</strong>t<strong>en</strong> have thorns, e.g. Fagara macrophylla. Stilt roots are abundant. Xylopia 'group<br />
I " Alchornea floribunda, Anthonotha macrophylla, Megaphrynium secundiflorum and Ouratea<br />
flava are <strong>the</strong> most common species. The herb layer is ra<strong>the</strong>r op<strong>en</strong> and has an average height <strong>of</strong> 50<br />
cm. Broad-leaved herbs t<strong>en</strong>d to dominate. Characteristic species are Stylochiton z<strong>en</strong>keri,<br />
Thaumantococcus 'group I', Haumannia danckelmanniana, Palisotha ambigua, Rektophylium<br />
'group I' and Stipularia africana.<br />
This community is <strong>the</strong> typical fallow vegetation in shifting cultivation areas and is found near<br />
villages and along <strong>the</strong> main access roads, throughout <strong>the</strong> TCP area. To a lesser ext<strong>en</strong>t it is found<br />
in logged-over forests. It is induced by human activity and appears to be ra<strong>the</strong>r ins<strong>en</strong>sitive to soil<br />
, and landform variation. The Xylopia - Musanga community forms a transitional stage betwe<strong>en</strong> <strong>the</strong><br />
Macaranga - Chromola<strong>en</strong>a community (V) and old secondary forest types (<strong>II</strong>a, llb, <strong>II</strong>c and Ill; all<br />
p.p.). It develops some five years after fallow.<br />
The vegetation can be typified as evergre<strong>en</strong> broad-leaved woodland in <strong>the</strong> UNESCO classification<br />
<strong>of</strong> vegetation (UNESCO, 1981). The distribution <strong>of</strong> <strong>the</strong> Xylopia - Musanga community within <strong>the</strong><br />
TCP research area coincides with Letouzey's type n° 251, i.e. remnants <strong>of</strong> strongly degraded<br />
evergre<strong>en</strong> forests. Physiognomy and species composition is also comparable although some<br />
elem<strong>en</strong>ts <strong>of</strong> Letouzey's 'strongly degraded remnants <strong>of</strong> semi-deciduous forest' (type nO 169) are<br />
also pres<strong>en</strong>t.<br />
6.4.7 Macaranga - Chromola<strong>en</strong>a community (V)<br />
The Macaranga - Chromola<strong>en</strong>a community forms thickets on rec<strong>en</strong>tly abandoned fields and in<br />
cacao plantations. The differ<strong>en</strong>tiating species <strong>of</strong> this community are Macaranga 'group I',<br />
Chromola<strong>en</strong>a odorata, Albyzia zygia, Costus violaceus, Milicia excelsa, Rauvolfia vomitoria and<br />
Ceiba p<strong>en</strong>tandra. In addition, some cultivated species are still pres<strong>en</strong>t, e.g. Trifolium 'species I'<br />
(groundnut), Manihot escul<strong>en</strong>ta (cassava), Colocasia 'species l' (coco-yam) and Musa 'species<br />
I' (plantain).<br />
67
In <strong>the</strong> shrub like vegetation <strong>of</strong> <strong>of</strong> <strong>the</strong> Macaranga - Chromola<strong>en</strong>a community three three (sometimes (sometimes only<br />
two) structural layers can be be discerned. The tree layer is very op<strong>en</strong> (20-40%) and is very low (8-15<br />
m). The canopy is formed by trees and palms. The most frequ<strong>en</strong>t species are, in desc<strong>en</strong>ding order,<br />
Musanga cecropioides, Albyzia zygia, Pycnanthus angol<strong>en</strong>sis, Antocleista vogelii and Elaeis<br />
guine<strong>en</strong>sis. The most characteristic feature <strong>of</strong> <strong>the</strong> vegetation <strong>of</strong> this community is <strong>the</strong> very d<strong>en</strong>se<br />
and high shrub layer (up to to five five meters) meters) in which which broad-leaved robust herbs are by far <strong>the</strong> dominant<br />
growth form. Additionally, broad-leaved trees, palms, lianas are also also pres<strong>en</strong>t. The vegetation is<br />
literally overgrown by Chromola<strong>en</strong>a odorata. O<strong>the</strong>r non-woody species are Costus violaceus,<br />
Aframomum alboviolaceum, Megaphrynium Megaphrynium secundiflorum, Thaumantococcus daniellii daniellii and<br />
Palisota ambigua. Characteristic woody species <strong>of</strong> <strong>the</strong> shrub layer are Funtumia elastica,<br />
Macaranga 'group 1', Rauvolfia macrophylla, Eleais gui<strong>en</strong><strong>en</strong>s is and F agara agara macrophylla. macrophylla. Also<br />
many residual agricultural crops are pres<strong>en</strong>t, e.g. Musa parodisiaca, Manihot escul<strong>en</strong>ta, Colocasia<br />
sp. and Carica papaya. Underneath <strong>the</strong> d<strong>en</strong>se shrub layer, a very op<strong>en</strong> (20%) and low herb layer<br />
(20-40 cm) can be distinguished. Here, herbs, ferns and seedlings form <strong>the</strong> majority <strong>of</strong> <strong>the</strong> plant<br />
life <strong>en</strong>countered. Oft<strong>en</strong> Trifolium sp. is abundant.<br />
The Macaranga - Chromola<strong>en</strong>a community is found in <strong>the</strong> vicinity <strong>of</strong> villages and roads and is<br />
strongly related to rec<strong>en</strong>t agricultural activities. It is most common on on <strong>the</strong> dissected plains in in <strong>the</strong> <strong>the</strong><br />
western part <strong>of</strong> <strong>of</strong> <strong>the</strong> TCP TCP area, and in <strong>the</strong> surroundings <strong>of</strong> <strong>Akom</strong> H. It does not occur (yet) at<br />
altitudes above above 600 600 m asl..<br />
The vegetation is typical for rec<strong>en</strong>tly abandoned abandoned fields, approximately betwe<strong>en</strong> betwe<strong>en</strong> one and and five years years<br />
after cultivation. Also Cacao Cacao (Theobroma cacao) plantations plantations with a lush understorey <strong>of</strong> broadleavedleaved<br />
herbs are part <strong>of</strong> this community group. Many transitions betwe<strong>en</strong> this community and<br />
young secondary forests (community IV) are found.<br />
The Macaranga-Chromola<strong>en</strong>a community can be classified as an evergre<strong>en</strong> broad-leaved thicket<br />
according to <strong>the</strong> UNESCO UNESCO vegetation classification (1981). Because <strong>of</strong> <strong>the</strong> small scale <strong>of</strong> his<br />
phytogeographic map, Letouzey (1985, (1985, see Figure 6.1) incorporates <strong>the</strong>se <strong>the</strong>se rec<strong>en</strong>tly abandoned<br />
agricultural fields in type n° 251, i.e. remnants <strong>of</strong> strongly degraded evergre<strong>en</strong> forest. Physiognomy<br />
and species composition correspond closely closely to what he describes describes as 'ultimate degraded remnants<br />
<strong>of</strong> evergre<strong>en</strong> and semi-deciduous forest' (type nO 170).<br />
68 68
7. LANDSCAPE ECOLOGICAL MAP<br />
7.1 LEGEND<br />
Four altitude zones, sev<strong>en</strong> differ<strong>en</strong>t landforms, four main soil types and sev<strong>en</strong> broadly defined<br />
plant communities form <strong>the</strong> basis <strong>of</strong> <strong>the</strong> reconnaissance landscape ecological map <strong>of</strong> <strong>the</strong> TCP<br />
research area (Annex I.) The leg<strong>en</strong>d <strong>of</strong> <strong>the</strong> <strong>the</strong> landscape ecological map is based on altitude, landform,<br />
soil and vegetation, and has a hierarchical structure. A total <strong>of</strong> 14 main land mapping units is<br />
discerned. These units are fur<strong>the</strong>r subdivided based on vegetation characteristics, resulting in 34<br />
mapping units. Each mapping unit is repres<strong>en</strong>ted by a code, which is a combination <strong>of</strong> <strong>the</strong><br />
ecological zone (A to E) and <strong>the</strong> predominant landform (v, pd, ul, u2, hI, h2 and m). The leg<strong>en</strong>d<br />
is pres<strong>en</strong>ted on <strong>the</strong> landscape ecological map (Annex 1).<br />
Five ecological zones are id<strong>en</strong>tified and form <strong>the</strong> highest level <strong>of</strong> division <strong>of</strong> <strong>the</strong> leg<strong>en</strong>d. Soil<br />
drainage and altitude are <strong>the</strong> differ<strong>en</strong>tiating criteria on this level. Four <strong>of</strong> <strong>the</strong> ecological zones have<br />
well to moderately well drained soils. The altitude ranges <strong>of</strong> <strong>the</strong>se four ecological zones are: > 700<br />
m asl (zone A), 500-700 m asl (zone B), 350-500 m asl (zone C) and < 350 m asl (zone D). The<br />
fifth ecological zone (zone E) comprises swamp forests forests on poorly to very poorly drained soils. soils.<br />
Altitude is not differ<strong>en</strong>tiating for this zone. Although Although swamp <strong>en</strong>vironm<strong>en</strong>ts are found found locally<br />
throughout <strong>the</strong> study area, only those <strong>of</strong> suffici<strong>en</strong>t size to be mapped individually on<br />
reconnaissance scale are considered part <strong>of</strong> this ecological zone. Small swamp areas occur as part<br />
<strong>of</strong> <strong>the</strong> vegetation and soil complexes within <strong>the</strong> zones B, C and D.<br />
Landform has be<strong>en</strong> introduced at <strong>the</strong> second level <strong>of</strong> <strong>the</strong> leg<strong>en</strong>d. Sev<strong>en</strong> landforms are discerned:<br />
valley bottom (v), dissected erosional plain (pd), rolling upland (ul), hilly upland (u2), isolated hill<br />
(hI), complex <strong>of</strong> hills (h2) and mountain (m). Their characteristics are discussed in chapter 4.<br />
At <strong>the</strong> third level <strong>of</strong> <strong>the</strong> leg<strong>en</strong>d <strong>the</strong> characteristics <strong>of</strong> soils and vegetation <strong>of</strong> each landform unit<br />
within a particular ecological zone are giv<strong>en</strong>. These aspects are described in <strong>the</strong> chapters 5 and 6.<br />
7.2 LANDUSE<br />
The aerial photographs, on which <strong>the</strong> pres<strong>en</strong>t landscape ecological map is based, were tak<strong>en</strong> in<br />
1983-1985. Rec<strong>en</strong>t changes in vegetation cover can <strong>the</strong>refore not be accounted for. Field<br />
observations suggest that especially dynamic forms <strong>of</strong> land use such as shifting cultivation and<br />
commercial logging have affected <strong>the</strong> vegetation to a considerable ext<strong>en</strong>t during <strong>the</strong> last t<strong>en</strong> years.<br />
The natural vegetation <strong>of</strong> <strong>the</strong> above described landscape ecological units has be<strong>en</strong> affected by<br />
agricultural practices. Based on <strong>the</strong> 1983-1985 aerial photographs a subdivision <strong>of</strong> <strong>the</strong> land<br />
mapping mapping units into 'relatively 'relatively undisturbed undisturbed areas', 'Iow int<strong>en</strong>sity int<strong>en</strong>sity shifting cultivation cultivation areas' and<br />
'high int<strong>en</strong>sity shifting cultivation areas' is made. The degree <strong>of</strong> disturbance in each unit<br />
determines <strong>the</strong> composition <strong>of</strong> <strong>the</strong> vegetation. Relatively undisturbed areas are characterized by<br />
<strong>the</strong> (near complete) abs<strong>en</strong>ce <strong>of</strong> agricultural fields. These areas cover about 70% <strong>of</strong> <strong>the</strong> TCP area<br />
or 116,170 ha. Within <strong>the</strong> Iow int<strong>en</strong>sity shifting cultivation areas actual and rec<strong>en</strong>tly abandoned<br />
agricultural fields cover less than 20% <strong>of</strong> <strong>the</strong> unit. Young secondary vegetation accounts for<br />
ano<strong>the</strong>r ano<strong>the</strong>r 20%. 20%. The The Iow Iow int<strong>en</strong>sity shifting cultivation covers about 18% 18% or 29,800 ha. In <strong>the</strong> high<br />
int<strong>en</strong>sity shifting cultivation areas actual fields and rec<strong>en</strong>tly abandoned agricultural fields cover<br />
more than 40% Additionally, more than 20% <strong>of</strong> <strong>the</strong> unit is young secondary forest. The high<br />
69
int<strong>en</strong>sity shifting cultivation takes up about 13% <strong>of</strong><strong>the</strong> TCP area or 21,360 ha. ha. Within <strong>the</strong> shifting shifting<br />
cultivation areas patches <strong>of</strong> forest are found, both undisturbed and disturbed.<br />
Unlike shifting cultivation activities, which are strongly conc<strong>en</strong>trated in specific areas, <strong>the</strong> impact<br />
<strong>of</strong> <strong>of</strong> logging on <strong>the</strong> forest vegetation could not be mapped accurately. This is primarily due to scale<br />
problems. Moreover, with time <strong>the</strong> <strong>the</strong> differ<strong>en</strong>ces betwe<strong>en</strong> ext<strong>en</strong>sively ext<strong>en</strong>sively logged-over forest and and 'virgin'<br />
forest stands stands become quite quite subtle, whereas whereas <strong>the</strong> <strong>the</strong> sev<strong>en</strong> plant communities giv<strong>en</strong> in in <strong>the</strong> <strong>the</strong> leg<strong>en</strong>d are<br />
broadly defined. Each <strong>of</strong> <strong>the</strong> five types <strong>of</strong> relatively undisturbed forest (1, lIa, llb, lIc and Ill) in in<br />
fact comprise both virgin stands and various reg<strong>en</strong>eration reg<strong>en</strong>eration stages <strong>of</strong> old secondary forest. During<br />
<strong>the</strong> second phase <strong>of</strong><strong>the</strong> LUl-project <strong>the</strong> <strong>the</strong> distribution and floristic composition <strong>of</strong> <strong>the</strong>se <strong>the</strong>se 'variants'<br />
are studied in more detail.<br />
7.3 LAND MAPPING UNITS<br />
The The characteristics <strong>of</strong> <strong>the</strong> fourte<strong>en</strong> main land mapping units <strong>of</strong> <strong>the</strong> landscape landscape ecological map are are<br />
pres<strong>en</strong>ted in <strong>the</strong> following section. For more elaborate descriptions <strong>of</strong> <strong>the</strong> landforms, soil types and<br />
plant communities refer<strong>en</strong>ce is made to <strong>the</strong> chapters 4,5 and 6. The two table below summarize<br />
<strong>the</strong> spatial coverages <strong>of</strong> each main mapping unit.<br />
Table 7.1a Surface Surface areas in ha <strong>of</strong> <strong>of</strong> <strong>the</strong> main land mapping mapping units<br />
Main mapping unit Surface Surface area in in ha. ha.<br />
Ahl 880<br />
Am 10,060<br />
Bhl 3,820<br />
Bh2 13,890<br />
Bul 5,400<br />
Bu2 19,700 19,700<br />
ChI ChI 4,520<br />
CuI 31,270<br />
Cu2 25,070<br />
Dhl 3,310<br />
Dpd 11,260<br />
DuI 12,620<br />
Du2 23,950<br />
Ev 1,600<br />
Total TCP 167,350<br />
Table 7.1b Ext<strong>en</strong>t <strong>of</strong> <strong>of</strong> <strong>the</strong> areas influ<strong>en</strong>ced by shifting cultivation<br />
Int<strong>en</strong>sity <strong>of</strong> shifting cultivation<br />
No to hardly any (u)<br />
Low int<strong>en</strong>sity (I)<br />
High int<strong>en</strong>sity (h)<br />
Ext<strong>en</strong>t Ext<strong>en</strong>t (ha)<br />
116,170<br />
29,820<br />
21,360<br />
% <strong>of</strong> total<br />
0.5<br />
6.0 6.0<br />
2.3<br />
8.3 8.3<br />
3.2<br />
11.8<br />
2.7<br />
18.7<br />
15.0<br />
2.0<br />
6.7<br />
7.5<br />
14.3<br />
1.0<br />
100.0<br />
% % <strong>of</strong> total<br />
7.3.1 Am: mountains above 700 m as), well drained soils<br />
The Am land mapping units coincide with <strong>the</strong> Bingalanda mountain range in <strong>the</strong> eastern part <strong>of</strong><br />
<strong>the</strong> TCP area, with altitudes betwe<strong>en</strong> 700 and 1,000 m asl. They cover a surface area <strong>of</strong> 10,000<br />
ha. The mountainous mountainous area is strongly strongly dissected dissected and has steep steep outer outer slopes. Valley bottoms are are<br />
narrow and cover only very limited surfaces. The soils are very very clayey and belong belong to <strong>the</strong><br />
70<br />
69.4<br />
17.8<br />
12.8
Nyangong type. The predominant forest type is <strong>the</strong> submontane Maran<strong>the</strong>s-Anisophyllea<br />
community (I). In g<strong>en</strong>eral, <strong>the</strong> vegetation is not affected by human activity.<br />
7.3.2 Ah1: isolated hills above 700 m asl, well drained soils<br />
These mapping units are found along <strong>the</strong> fringes <strong>of</strong> <strong>the</strong> Bingalanda massive in <strong>the</strong> eastern part<br />
<strong>of</strong> <strong>the</strong> TCP area where <strong>the</strong>y cover some 880 ha. The altitude <strong>of</strong> <strong>the</strong> isolated hills vary from 700<br />
to 900 m as!. Valley bottoms are not included in this unit. The soils are very clayey (Nyangong).<br />
The predominant forest type is <strong>the</strong> submontane Maran<strong>the</strong>s - Anisophyllea community (I).<br />
Human activities have not altered <strong>the</strong> vegetation in <strong>the</strong>se units.<br />
7.3.3 Bh2: complex <strong>of</strong> hills betwe<strong>en</strong> 500 and 700 m asl, well drained soils<br />
Mapping units Bh2 are complexes <strong>of</strong> hills betwe<strong>en</strong> 500 and 700 m asl, and are found in <strong>the</strong><br />
strongly dissected eastern part <strong>of</strong> <strong>the</strong> TCP research area. They cover large surfaces just west <strong>of</strong><br />
<strong>the</strong> Bingalanda mountain range and have a g<strong>en</strong>eral SW-NE ori<strong>en</strong>tation. In addition, Bh2 units<br />
are found in <strong>the</strong> southwestern part <strong>of</strong> <strong>the</strong> TCP research area, where <strong>the</strong>y form <strong>the</strong> foothills <strong>of</strong> <strong>the</strong><br />
mountain range that is situated west <strong>of</strong> <strong>the</strong> TCP research area. The total surface area <strong>of</strong> <strong>the</strong>se<br />
mapping units is some 13,890 ha. The dominant soils are very clayey (Nyangong). Valley<br />
bottoms are narrow and cover only limited surfaces. The vegetation is predominantly primary<br />
and old secondary lowland forest <strong>of</strong> <strong>the</strong> Podococcus-Polyalthia community (Ha). Human<br />
activities have not altered <strong>the</strong> vegetation <strong>of</strong> <strong>the</strong>se units.<br />
7.3.4 Bh1: isolated hills betwe<strong>en</strong> 500 and 700 m asl, well drained soils<br />
These mapping units are found scattered as small patches in <strong>the</strong> eastern part <strong>of</strong> <strong>the</strong> TCP area.<br />
Although <strong>the</strong>ir total area does not cover more than 3,820 ha, <strong>the</strong> isolated hills form a<br />
characteristic aspect <strong>of</strong> <strong>the</strong> landscape. The elevation <strong>of</strong> <strong>the</strong> hills is betwe<strong>en</strong> 500 to 700 m as!.<br />
The soils are very clayey and belong to <strong>the</strong> Nyangong type. Valley bottoms are almost<br />
completely abs<strong>en</strong>t. The vegetation is predominantly primary and old secondary lowland forest<br />
<strong>of</strong> <strong>the</strong> Podococcus-Polyalthia community (Ha). Human activities have not altered <strong>the</strong> vegetation<br />
<strong>of</strong> <strong>the</strong>se <strong>the</strong>se units.<br />
7.3.5 Bu2: hilly uplands betwe<strong>en</strong> 500 and 700 m asl; well drained soils<br />
The hilly uplands <strong>of</strong> <strong>the</strong> Bu2 units cover some 19,700 ha. They are located at <strong>the</strong> foot <strong>of</strong> <strong>the</strong><br />
Bingalanda mountain range in <strong>the</strong> eastern part <strong>of</strong> <strong>the</strong> TCP area and in <strong>the</strong> nor<strong>the</strong>astern part <strong>of</strong><br />
<strong>the</strong> area. The uplands are strongly dissected and valley bottoms are estimated to cover betwe<strong>en</strong><br />
5 and 10% <strong>of</strong> <strong>the</strong>ir surface. The soils are an association <strong>of</strong> very clayey Nyangong soils and <strong>the</strong><br />
clayey Ebom ones. The predominant vegetation type <strong>of</strong> <strong>the</strong>se units is <strong>the</strong> primary and old<br />
secondary lowland forest <strong>of</strong> <strong>the</strong> Podococcus - Polyalthia community (Ha). The valley bottoms<br />
are characterized by poorly drained soils and by <strong>the</strong> swamp forest <strong>of</strong> <strong>the</strong> Carapa - Mitragyna<br />
community (<strong>II</strong>I).<br />
The units are to a limited ext<strong>en</strong>t affected by agricultural practices. Only along <strong>the</strong> roads some<br />
low int<strong>en</strong>sity <strong>en</strong>croachm<strong>en</strong>t is visible on <strong>the</strong> 1984-1985 air photo's. photo'S. In <strong>the</strong>se areas, especially<br />
near <strong>the</strong> villages Nyangong and Ebemvok, <strong>the</strong> composition <strong>of</strong> <strong>the</strong> vegetation has gradually be<strong>en</strong><br />
changing into a mosaic <strong>of</strong> thicket <strong>of</strong> <strong>the</strong> Macaranga - Chromola<strong>en</strong>a community (V), young<br />
secondary forest <strong>of</strong> <strong>the</strong> Xylopia - Musanga community (IV), and lowland forest <strong>of</strong> <strong>the</strong><br />
Podococcus - Polyalthia community (Ha).<br />
7.3.6 Bu1: rolling uplands betwe<strong>en</strong> 500 and 700 m asl; well drained soils<br />
Rolling uplands betwe<strong>en</strong> 500 and 700 m asl are only found in <strong>the</strong> most eastern part <strong>of</strong> <strong>the</strong> TCP<br />
area, where <strong>the</strong>y cover a total surface area <strong>of</strong> 5,400 ha. The rolling uplands are moderately<br />
dissected and valley bottoms are estimated to cover 10 to 15% <strong>of</strong> <strong>the</strong>se mapping units. In places,<br />
71
<strong>the</strong>se valley bottoms are suffici<strong>en</strong>tly large to be mapped individually. The soils form an<br />
association <strong>of</strong>Nyangong and Ebom types. The valley bottoms are typically poorly to very poorly<br />
drained and are occupied by swam forest <strong>of</strong> <strong>the</strong> Carapa - Mitragyna community (Ill).<br />
The Bul units are affected by human activities especially near <strong>the</strong> village <strong>of</strong>Nyangong a large<br />
area with low int<strong>en</strong>sity shifting cultivation area has be<strong>en</strong> discerned. Primary and old secondary<br />
lowland forest <strong>of</strong> <strong>the</strong> Podococcus-Polyalthia (lIa) community is <strong>the</strong> predominant vegetation <strong>of</strong><br />
<strong>the</strong> relatively undisturbed areas. The shifting cultivation areas are characterized by a vegetation<br />
mosaic that contains obviously disturbed lowland forest forest <strong>of</strong> <strong>the</strong> Podococcus -Polyalthia<br />
community, young secondary forest <strong>of</strong> <strong>the</strong> Xylopia - Musanga community (IV) and thicket <strong>of</strong><br />
<strong>the</strong> Macaranga - Chromola<strong>en</strong>a community (V).<br />
7.3.7 ChI: isolated hills betwe<strong>en</strong> 350 and 500 m asl, well drained soils<br />
The isolated hills form a characteristic aspect <strong>of</strong> <strong>the</strong> c<strong>en</strong>tral and nor<strong>the</strong>rn region <strong>of</strong> <strong>the</strong> TCP area,<br />
which is mainly composed <strong>of</strong> uplands. The characteristically scattered hills cover a total surface<br />
area <strong>of</strong> 4,520 ha. Within <strong>the</strong> Ch 1 units no valley bottoms are found. The soils are predominantly<br />
clayey and are classified classified as Ebom soils. The vegetation is primary and old secondary forest <strong>of</strong><br />
<strong>the</strong> Strombosia - Polyalthia community (lIb). Human activities have not affected <strong>the</strong> vegetation<br />
<strong>of</strong> <strong>the</strong>se units, most likely because <strong>of</strong> <strong>the</strong> steep slopes,<br />
7.3.8 Cu2: hilly uplands betwe<strong>en</strong> 350 and 500 m asl; well drained soils<br />
These mapping units occupy considerable surface areas, i.e., 25,070 ha, in <strong>the</strong> c<strong>en</strong>tral and<br />
nor<strong>the</strong>rn regions <strong>of</strong> <strong>the</strong> TCP area. The g<strong>en</strong>eral ori<strong>en</strong>tation <strong>of</strong> <strong>the</strong>se mapping units is SW-NE. The<br />
uplands are strongly dissected and an estimated 5 to 10% <strong>of</strong> <strong>the</strong>ir surface are covered by valley<br />
bottoms. The soils <strong>of</strong> <strong>the</strong> higher parts are clayey (Ebom type) and those <strong>of</strong> <strong>the</strong> valley bottoms<br />
are typically poorly to very very poorly poorly drained. The vegetation <strong>of</strong> <strong>the</strong> well well drained part part <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Cu2<br />
units is primary primary and old secondary lowland <strong>of</strong> <strong>the</strong> Strombosia - Polyalthia community (lIb).<br />
Swamp forest <strong>of</strong> <strong>the</strong> Carapa - Mitragyna community (Ill) covers <strong>the</strong> valley bottoms.<br />
Shifting cultivation is restricted to <strong>the</strong> sou<strong>the</strong>rn edge <strong>of</strong> <strong>the</strong> unit near <strong>the</strong> villages <strong>of</strong> Adjab and<br />
<strong>Akom</strong> 1I <strong>II</strong> and to <strong>the</strong> nor<strong>the</strong>rn parts and is g<strong>en</strong>erally <strong>of</strong> low int<strong>en</strong>sity. The vegetation in <strong>the</strong>se areas<br />
is a mosaic <strong>of</strong> obviously disturbed lowland forest <strong>of</strong> <strong>the</strong> Strombosia - Polyalthia community<br />
(lIb), and young secondary vegetation <strong>of</strong> <strong>the</strong> Xylopia - Musanga community (IV), and and <strong>the</strong><br />
Macaranga - Chromola<strong>en</strong>a Chromola<strong>en</strong>a community (V). Fur<strong>the</strong>rmore it is observed that most <strong>of</strong> <strong>the</strong> forest<br />
has be<strong>en</strong> logged in <strong>the</strong> rec<strong>en</strong>t past. past.<br />
7.3.9 CuI: rolling uplands betwe<strong>en</strong> 350 and 500 m asl; well drained soils<br />
The rolling uplands betwe<strong>en</strong> 350 and 500 m asl also occupy considerable surface areas, i.e.<br />
31,270 ha, in <strong>the</strong> c<strong>en</strong>tral and nor<strong>the</strong>rn regions <strong>of</strong> <strong>the</strong> TCP area. With <strong>the</strong> mapping units Cu2<br />
(hilly uplands) <strong>the</strong>y form <strong>the</strong> major land mapping units <strong>of</strong> this regions. Both units have a similar<br />
SW to NE direction and are found to alternate. Some 10 to 15% <strong>of</strong> <strong>the</strong> rolling uplands are<br />
occupied by valley bottoms. The dominating soils <strong>of</strong> <strong>the</strong> slope and summit areas are clayey<br />
Ebom soils, whereas <strong>the</strong> soils <strong>of</strong> <strong>the</strong> valley bottoms are typically poorly to very poorly drained.<br />
The well drained areas are covered by primary and old secondary lowland forest <strong>of</strong> <strong>the</strong><br />
Strombosia - Polyalthia community (lIb), whereas <strong>the</strong> vegetation <strong>of</strong> <strong>the</strong> valley bottoms belongs<br />
to <strong>the</strong> Carapa - Mitragyna community (Ill).<br />
Near villages and roads considerable parts <strong>of</strong> <strong>the</strong> Cu rolling uplands are occupied by high<br />
int<strong>en</strong>sity shifting cultivation. The vegetation in <strong>the</strong>se areas is characterized by patches <strong>of</strong><br />
obviously disturbed lowland forest <strong>of</strong> <strong>the</strong> Strombosia - Polyalthia community (lIb) and by a<br />
mosaic <strong>of</strong> young secondary vegetation: <strong>the</strong> Xylopia - Musanga community (IV), and <strong>the</strong><br />
72
Within <strong>the</strong> shifting cultivation areas <strong>the</strong> vegetation is a mosaic <strong>of</strong> actual fields, thickets <strong>of</strong> <strong>the</strong><br />
Macaranga - Chromola<strong>en</strong>a community CV) on rec<strong>en</strong>tly abandoned fields, young secondary<br />
forest <strong>of</strong> <strong>the</strong> Xylopia - Musanga community (IV), and patches <strong>of</strong> lowland forest <strong>of</strong> <strong>the</strong> Diospyros<br />
- Polyalthia community (<strong>II</strong>c).<br />
7.3.13 Dpd: dissected erosional plains below 350 m asl; moderately well drained soils<br />
The dissected erosional plains plains are found found in <strong>the</strong> <strong>the</strong> northwest <strong>of</strong> <strong>of</strong> <strong>the</strong> TCP area. The The low relief relief<br />
int<strong>en</strong>sity and low altitude (40 to to 200 m asl) are a characteristic characteristic features <strong>of</strong> <strong>the</strong> landscape. These<br />
units cover a surface area <strong>of</strong> 11,260 ha and an estimated 10-15% <strong>of</strong> <strong>the</strong>m are valley bottoms.<br />
The soils are an association <strong>of</strong> Ebimimbang and Valley Bottom soils.<br />
No significant stretch <strong>of</strong> natural forest is found within <strong>the</strong>se units which are <strong>the</strong> core <strong>of</strong> <strong>the</strong><br />
shifting cultivation area <strong>of</strong> <strong>the</strong> TCP area. These units have at least three times be<strong>en</strong> logged for<br />
commercial timber. The units have be<strong>en</strong> id<strong>en</strong>tified as high int<strong>en</strong>sity shifting cultivation areas<br />
and <strong>the</strong> vegetation is a mosaic <strong>of</strong> actual fields, rec<strong>en</strong>tly abandoned fields with <strong>the</strong> Macaranga -<br />
Chromola<strong>en</strong>a community (V), (V), young young secondary forest (Xylopia - Musanga community (IV» and<br />
obviously disturbed lowland lowland forest (Diospyros - Polyalthia community (<strong>II</strong>c».<br />
7.3.14 Ev: valley bottom; poorly poorly to very poorly drained soils<br />
Valley bottoms occur throughout <strong>the</strong> TCP area. The majority however is too small to be mapped<br />
individually at reconnaissance scale and appears as inclusions in o<strong>the</strong>r mapping units. Some<br />
large valley bottom areas, however, do exist throughout <strong>of</strong> <strong>the</strong> TCP research area. The total<br />
surface <strong>of</strong> <strong>the</strong>se units is only 1,600 ha.<br />
Because <strong>of</strong> <strong>the</strong> high ground water table and water stagnation, <strong>the</strong> vegetation structure and<br />
composition are very distinct. The soils are typically poorly to very poorly drained, are shallow<br />
to moderately deep and stratified, i.e. alternation <strong>of</strong> sand and clay. The swamp forest is<br />
characterized by <strong>the</strong> Carapa - Mitragyna (Ill) community. The Ev units appear not to be<br />
affected by by human activity.<br />
74
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for Eburnian and Pan-African high-grade metamorphism in cratonic rocks <strong>of</strong> sou<strong>the</strong>rn<br />
Cameroon. Precambrian Research 67: 67: 321-347.<br />
Touber, Touber, L. (1993a). Air photo interpretation for overall land inv<strong>en</strong>tory <strong>of</strong> <strong>the</strong> research area<br />
(TCP, LUJ). Explanatory note. Internal docum<strong>en</strong>t, SC-DLO, Wag<strong>en</strong>ing<strong>en</strong>, <strong>the</strong> Ne<strong>the</strong>rlands.<br />
Touber, L. (1993b). Report on a mission in support <strong>of</strong> <strong>the</strong> Land Inv<strong>en</strong>tory Project in <strong>the</strong><br />
Trop<strong>en</strong>bos Cameroon Programme. International Activities Report 32. SC-DLO, Wag<strong>en</strong>ing<strong>en</strong>,<br />
<strong>the</strong> Ne<strong>the</strong>rlands.<br />
Touber, L., Rand<strong>en</strong>, Y. van and Gijs<strong>en</strong>, N. (1993). Tr<strong>of</strong>olin database. User manual. Trop<strong>en</strong>bos<br />
Docum<strong>en</strong>ts 4. The Trop<strong>en</strong>bos Foundation, Wag<strong>en</strong>ing<strong>en</strong>, <strong>the</strong> Ne<strong>the</strong>rlands.<br />
Touber, L., Smaling, E.M.A., Andriesse, W. and Hakkeling, R.T.A. (1989). Inv<strong>en</strong>tory and<br />
evaluation <strong>of</strong> tropical forest land. Guidelines for a common methodology. Trop<strong>en</strong>bos<br />
Technical Series 4. The The Trop<strong>en</strong>bos Foundation, Ede, <strong>the</strong> Ne<strong>the</strong>rlands.<br />
UNESCO. (1981). Carte de la vegetation d'Amerique du Sud. Recherches sur les resources<br />
natureUes N. 17. Unesco, Paris, France.<br />
Vivi<strong>en</strong>, J. (1991). Faune du Cameroun: guide des mammiflres et poissons. GlCAM & Ministere<br />
de la Cooperation et du Developpem<strong>en</strong>t, Yaounde, Cameroon.<br />
Waterloo, M.J., Ntonga, J.C., Dolman, Dolman, A.J. and Ayangma, A.B. (1997). Studies on <strong>the</strong> impact<br />
<strong>of</strong> land use on <strong>the</strong> hydrology and erosion <strong>of</strong> rain forest land in South Cameroon. DLO<br />
Winand Staring C<strong>en</strong>tre Report 134. SC-DLO, Wag<strong>en</strong>ing<strong>en</strong>, <strong>the</strong> Ne<strong>the</strong>rlands.<br />
Whitmore, T.C. (1984). Tropical rainforests <strong>of</strong> <strong>the</strong> far east. Clar<strong>en</strong>don Press, Oxford, United<br />
Kingdom.<br />
Yemefack, M. and Moukam, A. (1995). Biophysical Land Resources Inv<strong>en</strong>tory and<br />
Characterization <strong>of</strong> ASB Forest Margin B<strong>en</strong>chmark sites <strong>of</strong>Cameroon. Report <strong>of</strong> <strong>the</strong> field<br />
tour carried out out from 13 13 to 18 18 November 1995. IRA/ ASB ASB Project, Yaounde, Yaounde, Cameroon.<br />
Zonneveld, J.I.S. (1981). Vorm<strong>en</strong> in het landschap. Ho<strong>of</strong>dlijn<strong>en</strong> van de geomorfologie. Het<br />
Spectrum, Utrecht/ Antwerp<strong>en</strong>, <strong>the</strong> Ne<strong>the</strong>rlands/Belgium.<br />
Zonneveld, I.S. (1995). Land Ecology. An introduction to landscape ecology as a base for land<br />
evaluation, land land managem<strong>en</strong>t and conservation. SPB SPB Academic Publishing, Amsterdam, Amsterdam, <strong>the</strong><br />
Ne<strong>the</strong>rlands.<br />
78
00<br />
o
ANNEX <strong>II</strong> List <strong>of</strong> aerial photographs 1983-1985, 1 :20,000 series covering <strong>the</strong><br />
TCP research area (Photo sur Inc.)<br />
Line Line number Photo numbers<br />
40 CAM - 84040 L-40 58- 60<br />
38 CAM- 84044 L-38 46- 53<br />
37 CAM CAM-- 84040 L-37 33- 42<br />
36 CAM - 84039 L-36 74- 87<br />
35 CAM- 84040 L-35 05- 11<br />
35 CAM - 84039 L-35 49- 68<br />
34 CAM - 84039 L-34 171-198<br />
33 CAM -- 85007 L-33 112-137 112-137<br />
32 CAM- 84029 L-32 34- 44<br />
32 CAM - 85019 L-32 58- 65<br />
32 CAM- CAM- 84046 L-32 65- 75<br />
31 CAM- 84046 L-31 88- 96<br />
31 CAM - 85023 L-31 57- 62<br />
31 CAM - 84046 L-31 99-101<br />
30 CAM - 85023 L-30 141-150<br />
30 CAM - 85025 L-30 142-154<br />
29 CAM - 85023 L-29 126-139<br />
29 CAM - 85023 L-29 63- 75<br />
29 CAM - 85025 L-29 163-167<br />
28 CAM - 85008 L-28 203-217<br />
27 CAM - 84041 L-27 99-118<br />
26 CAM - 84041 L-26 163-180<br />
24 CAM - 85010 L-24 23- 26<br />
81
ANNEX <strong>II</strong>I METHODS FOR CHEMICAL AND PHYSICAL SOIL ANALYSIS<br />
IlIA Laboratory <strong>of</strong> 'Institute de la Recherche Agricole pour le<br />
Developpem<strong>en</strong>t', D6veloppem<strong>en</strong>t', station Ekona<br />
IlIB Comparison <strong>of</strong> soil data analysed in duplo (IRAD, Ekona, Cameroon<br />
and ISRIC, Wag<strong>en</strong>ing<strong>en</strong>, The Ne<strong>the</strong>rlands)<br />
83
IlIA Laboratory <strong>of</strong> 'Institut de la Recherche Agricole pour le Developpem<strong>en</strong>t',<br />
station Ekona<br />
The analytical methods used are ess<strong>en</strong>tially those described in 'Soil and Plant Analysis, a series<br />
<strong>of</strong> syllabi. Part 5, Soil Analysis Procedures', published by <strong>the</strong> Departm<strong>en</strong>t <strong>of</strong> Soil Sci<strong>en</strong>ce and<br />
Plant Nutrition (Houba et al., 1989) and in 'Procedures for soil analysis'. Techn. Pap. No. 9 (5th<br />
ed.), published by by Int. Soil Ref. and and Info. C<strong>en</strong>tre (ISRIC) (Reeuwijk, 1995).<br />
Texture<br />
Air-dry samples are sieved through a 2 mm sieve, and <strong>the</strong> material retained is crushed and sieved<br />
again. The material> 2 mm is indicated as coarse fraction.<br />
The soil material finer than than 2 2 mm mm is is used used for particle size analysis analysis by <strong>the</strong> sieve and pipette method<br />
after treatm<strong>en</strong>t with H H20 20 2 to destroy organic matter, and HCI to dissolve carbonates, if pres<strong>en</strong>t, and<br />
o<strong>the</strong>r cem<strong>en</strong>ting ag<strong>en</strong>ts. The fractions obtained were < 2 Ilm (clay), 2-20 Ilm and 20-50 Ilm (silt),<br />
and 50-100 Ilm, 100-250 Ilm, 250-500 Ilm and 500-2000 Ilm. These fractions repres<strong>en</strong>t <strong>the</strong> USDA<br />
classes <strong>of</strong> very fine, fine, medium + coarse and very coarse sand respectively.<br />
Moisture cont<strong>en</strong>t (105 C)<br />
Air-dry samples are dried 24 hrs at 105°C to give <strong>the</strong> moisture cont<strong>en</strong>t.<br />
pH H 20 20 and KCl KCl<br />
The pH is is measured pot<strong>en</strong>tiometrically in <strong>the</strong> soil susp<strong>en</strong>sion susp<strong>en</strong>sion after after equilibrium on 24 24 hours. hours. The The<br />
soil to liquid ratio was 1:2.5. The liquid liquid was ei<strong>the</strong>r distilled water (pH-HP) or 1 M potassium<br />
chloride (pH-KCI).<br />
Organic carbon (Walkley-Black) %<br />
After <strong>the</strong> carbonization <strong>of</strong> soil organic matter with conc. conc. H H2S0 2S0 4 , carbon was oxidized oxidized by<br />
dichromate. The gre<strong>en</strong> chromium solution is read colorimetrically on Technicon Auto-Analyzer<br />
H. The method had a recovery <strong>of</strong> 75% <strong>of</strong> <strong>the</strong> total organic C, which is about 58% <strong>of</strong> <strong>the</strong> total<br />
organic matter.<br />
Total N (Kjeldahl) % %<br />
Catalytic oxidation <strong>of</strong> organic and chemically combined N and subsequ<strong>en</strong>t alteration to NH4<br />
(except N0 3 + N0 2 ) by <strong>the</strong> Kjeldahl process (Hesse, 1971). Nitrog<strong>en</strong> is measured on Technicon<br />
AAH.<br />
Available P (Bray-<strong>II</strong>) ppm<br />
The The soil is extracted extracted by a solution solution <strong>of</strong> 0.03 M NH4F and 0.1 0.1 M HCI. In this way, way, acid-soluble P, a<br />
major part <strong>of</strong> <strong>the</strong> calcium phosphates, and part <strong>of</strong> <strong>the</strong> aluminium and iron phosphates are extracted.<br />
NH4F dissolves aluminium and iron phosphates by formation <strong>of</strong> complexes with <strong>the</strong>se metal ions<br />
in acid solutions, th<strong>en</strong> measured on Technicon AA <strong>II</strong> (Ascorbic-Molybdate blue coloration).<br />
Total P (with H 2S0 2S0 4 and HN0 HN03 3 )<br />
The soil soil sample is is treated with with a a 1: 1 mixture <strong>of</strong> H 2S04 and RN0 RN0 3 • The catalyzer catalyzer is CuS04 CuS04 -Se -Se<br />
mixture (10: 1). In this step <strong>the</strong> larger part <strong>of</strong> <strong>the</strong> organic matter is oxidized. After decomposition<br />
<strong>of</strong> <strong>the</strong> excess and evaporation <strong>of</strong> water (boiling at 360°C for 3-5 hours), <strong>the</strong> digestion is finished<br />
by conc. H H2S0 2S0 4 • The molybd<strong>en</strong>um blue method is used to measure spectrophotometrically <strong>the</strong><br />
conc<strong>en</strong>tration <strong>of</strong> phosphates.<br />
84
CEC and exchangeable bases (with 1 M NH NH40Ac 40Ac pH 7)<br />
The soil is leached with a 1 M ammonium acetate solution (pH 7). The total amount <strong>of</strong> ammonium<br />
retained by <strong>the</strong> soil after washing it free <strong>of</strong> excess ammonium acetate is an estimate <strong>of</strong> <strong>the</strong> cation<br />
exchange capacity. The absorbed ammonium is released by leaching with acidified potassium<br />
chloride solution (pH 2.5) and subsequ<strong>en</strong>tly determined colorimetrically on Technicon AA H. In<br />
<strong>the</strong> first leachate Na, K, Ca and Mg are determined by spectrophotometry (Na, K and Ca with <strong>the</strong><br />
flame photometer and Mg colorimetrically by titan yellow method).<br />
AP+ and H+ (with KCI)<br />
Leaching with 1 M KCI and titration <strong>of</strong> exchangeable Al + H by 0.1 M NaOH.<br />
Moisture ret<strong>en</strong>tion (pF)<br />
The pF is measured with <strong>the</strong> help <strong>of</strong> moisture plates. pF is measured at 0 I / 0.1,0.3,1 and 15 bar<br />
(respectively pF 0/2,2.5,3.5 0 I 2,2.5,3.5 and 4.2).<br />
Bulk d<strong>en</strong>sity<br />
Soil samples tak<strong>en</strong> with <strong>the</strong> 100 cc pF rings are dried for 24 hours at 105 QC. The dry weight<br />
divided by 100 gives <strong>the</strong> bulk d<strong>en</strong>sity (g/cm3).<br />
divided by 100 gives <strong>the</strong> bulk d<strong>en</strong>sity (g/cm 3 ).<br />
X-ray diffraction <strong>of</strong> clay<br />
The clay fraction was separated from <strong>the</strong> fine-earth and deposited in an ori<strong>en</strong>tated fashion on<br />
porous ceramic plates to be analyzed on an X-ray diffractometer (Philips PW 182011710<br />
assembly). Various treatm<strong>en</strong>ts (e.g. glycerol, K-saturation, heating) were applied for id<strong>en</strong>tification<br />
oqhe various clay mineral species.<br />
85
<strong>II</strong>IB Comparison <strong>of</strong> soil data analyses in duplo (IRA, Ekona, Cameroon and<br />
ISRIC, Wag<strong>en</strong>ing<strong>en</strong>, The Ne<strong>the</strong>rlands)<br />
The comparison <strong>of</strong> soil data analyses at IRA, Ekona and ISRIC, Wag<strong>en</strong>ing<strong>en</strong>, The Ne<strong>the</strong>rlands is<br />
based based on Hommel Hommel & van Kekem's Kekem's mission mission report report (1996). (1996).<br />
Conditions<br />
All soil samples were analyses at IRA Ekona. Some samples were analyses in duplo. Also a<br />
selected set <strong>of</strong> soil samples were analysed at ISRIC, Wag<strong>en</strong>ing<strong>en</strong>, The Ne<strong>the</strong>rlands.<br />
Interpretation<br />
Interpretation<br />
First <strong>of</strong> all <strong>the</strong> course with depth <strong>of</strong> all elem<strong>en</strong>ts analyses were interpreted. The original data were<br />
compared with <strong>the</strong> duplo analysis <strong>of</strong> Ekona and ISRIC.<br />
Results<br />
Texture analysis do not show large variation comparing <strong>the</strong> data sets <strong>of</strong> Ekona and ISRIC. The<br />
texture with depth is becoming more clayey. The Ekona gravel data are higher as consequ<strong>en</strong>ce consequ<strong>en</strong>ce <strong>of</strong><br />
<strong>the</strong>ir method <strong>of</strong> sieving.<br />
The pH H H20 20 and pH KCI are in g<strong>en</strong>eral a little higher in <strong>the</strong> Ekona case. However <strong>the</strong> differ<strong>en</strong>ces<br />
betwe<strong>en</strong> <strong>the</strong> two data sets are always smaller than 0.5 unit.<br />
Organic matter conc<strong>en</strong>tration is sometimes a little higher in <strong>the</strong> surface horizons <strong>of</strong> <strong>the</strong> Ekona data<br />
set. The differ<strong>en</strong>t nitrog<strong>en</strong> conc<strong>en</strong>trations (Ekona and ISRIC) are comparable. C/N values are<br />
<strong>the</strong>refore higher, in <strong>the</strong> surface horizons <strong>of</strong> <strong>the</strong> Ekona data. The nitrog<strong>en</strong> and organic carbon<br />
conc<strong>en</strong>trations decrease with depth.<br />
Available Available and total total phosphorous phosphorous can not not be be compared compared as as consequ<strong>en</strong>ce consequ<strong>en</strong>ce <strong>of</strong> <strong>of</strong> differ<strong>en</strong>t differ<strong>en</strong>t methods methods used.<br />
Both data sets decrease also with depth.<br />
The The exchangeable bases sodium sodium (Na) (Na) and and potassium potassium (K) (K) are are exchangeable exchangeable within within <strong>the</strong> <strong>the</strong> data data sets. The The<br />
data do not differ more than 0.2 unit.<br />
Magnesium and calcium have sometimes large differ<strong>en</strong>ces (> 0.2 unit). The methods used in Ekona<br />
are susceptible to errors if <strong>the</strong> conc<strong>en</strong>trations <strong>of</strong> magnesium and calcium in <strong>the</strong> soil samples are<br />
low. Two third <strong>of</strong> <strong>the</strong> Ekona data is more than 0.2 unit (mainly) too high. Never<strong>the</strong>less <strong>the</strong><br />
differ<strong>en</strong>ces in total exchangeable bases betwe<strong>en</strong> <strong>the</strong> data sets are mostly smaller than 1 unit (in<br />
meq/lOO g).<br />
Aluminium (AP+) and hydrog<strong>en</strong> (H+) data differ not more than 1.5 and 0.4 unit, respectively. The<br />
hydrog<strong>en</strong> data have proportional large differ<strong>en</strong>ces (> 20%). Never<strong>the</strong>less <strong>the</strong> differ<strong>en</strong>ces in<br />
effective cation exchangeable capacity betwe<strong>en</strong> <strong>the</strong> data sets are in majority smaller than 2 units.<br />
In g<strong>en</strong>eral <strong>the</strong> Ekona data are higher than <strong>the</strong> ISRIC data.<br />
The Cation Exchange Capacity (CEC) is largely <strong>of</strong> <strong>the</strong> same order for <strong>the</strong> data sets « 2 units).<br />
Differ<strong>en</strong>ces occur mainly in <strong>the</strong> surface horizons. The surface horizon CEC values <strong>of</strong> Ekona are<br />
mainly lower than those <strong>of</strong>lSRIC.<br />
86
Conclusions<br />
The majority <strong>of</strong> original Ekona data I can be trusted as real values. The differ<strong>en</strong>ce betwe<strong>en</strong> <strong>the</strong><br />
original datal and <strong>the</strong> duplos and/or ISRIC data were small. Sometimes differ<strong>en</strong>ces were larger,<br />
but <strong>the</strong>y are ambiguous. Never<strong>the</strong>less this differ<strong>en</strong>ces were not that big that chemical<br />
characteristics <strong>of</strong> <strong>the</strong> pr<strong>of</strong>iles differ differ really betwe<strong>en</strong> <strong>the</strong> data sets <strong>of</strong> Ekona and ISRIC.<br />
The data used in <strong>the</strong> description <strong>of</strong> chemical and physical properties <strong>of</strong> <strong>the</strong> differ<strong>en</strong>t soil pr<strong>of</strong>iles<br />
were original Ekona datal. Exceptions were noted down in <strong>the</strong> descriptions <strong>of</strong> <strong>the</strong> analysis data.<br />
Original Ekona data concerning a certain sample are data <strong>of</strong> that sample which was first analysed.<br />
87
00<br />
00
ANNEX IV Soil pr<strong>of</strong>ile descriptions and data <strong>of</strong> analysis<br />
IV.A Nyangong soil type<br />
IV.B Ebom soil type<br />
IV.C Ebimimbang soil type<br />
IV.D Valley bottom soil type<br />
89
'"<br />
PROFILE 22<br />
Leg<strong>en</strong>d unit:<br />
Soil classification:<br />
Description:<br />
Location:<br />
Elevation:<br />
Landform and slope:<br />
Par<strong>en</strong>t material:<br />
Vegetation:<br />
Drainage:<br />
Soil:<br />
Depth (cm) Hor.<br />
0- 6 Ah<br />
6- 29 BA<br />
29- 60 Bwsl<br />
60-170 Bws2<br />
Bu2<br />
Xanthic Ferralsol (FAO)<br />
Typic Hapludox (Soil Taxonomy)<br />
On 22-03-95 by Gerard Hazeu and Arie van Kekem<br />
About 2 km E <strong>of</strong> Nko'Adjap village<br />
590 m<br />
Rolling to hilly uplands; middle slope 15%<br />
Gneisses <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Secondary forest<br />
Well drained<br />
Very deep, yellowish brown to strong brown clay<br />
Description<br />
brown to dark brown (7.5YR4/4); clay; strong, fme granular to subangular<br />
blocky; friable, slightly sticky and slightly plastic; abundant very fine to<br />
medium roots; clear and smooth transition to<br />
strong brown (7.5YR4/6); clay; moderate fine subangular blocky; friable,<br />
slightly sticky and slightly plastic; few to common, fine to medium roots;<br />
diffuse and smooth transition to<br />
strong brown (7.5YR5/6); clay; weak to moderate, fme subangular blocky;<br />
friable, slightly sticky and slightly plastic; patchy thin clay cutans; very<br />
few to few, fine to medium roots; diffuse and smooth transition to<br />
strong brown (7.5YR5!7); clay; weak fine subangular blocky; friable,<br />
slightly sticky and slightly plastic; patchy thin clay cutans; few very fine<br />
to fine roots.<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Bws2<br />
Horizon<br />
Ah<br />
BA<br />
BwsI<br />
Bws2<br />
Bws2<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Bws2<br />
Depth (cm)<br />
Protile 22<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in J.lm pH<br />
-..0<br />
w<br />
PROFILE 71<br />
Leg<strong>en</strong>d unit:<br />
Soil classification:<br />
Description:<br />
Location:<br />
Elevation:<br />
Landform and slope:<br />
Parem material:<br />
Vegetation:<br />
Drainage:<br />
Soil:<br />
Depth (cm) Hor.<br />
0- 3 Ah<br />
3- 8 BA<br />
8- 42 Bwsl<br />
42- 135 Bcl<br />
135- 195 Bc2<br />
Am<br />
Xanthic Ferralsol (FAO)<br />
Typic Hapludox (Soil Taxonomy)<br />
On 26-04-95 by Gerard Hazeu<br />
About 4 km SE <strong>of</strong>Bityili village; 2"56'06 Nand 10°49'55 E<br />
720 m<br />
Mountains; middle slope 30%<br />
Gneisses and/or diorite <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Forest<br />
Well drained<br />
Very deep, yellowish brown to strong brown clay<br />
Description<br />
dark yellowish brown (IOYR3/6); clay; weak to moderate, very fine to fine<br />
crumb to subangular blocky; friable, slightly sticky and slightly plastic;<br />
common to many, very fine to fine roots; clear and smooth transition to<br />
dark yellowish brown (IOYR4/6); clay; weak to moderate, fine subangular<br />
blocky; friable, slightly sticky and slightly plastic; few to common, very<br />
fine to fine roots; clear and smooth transition to<br />
yellowish brown (IOYR5/6); clay; weak fine to medium subangular<br />
blod:y; fim1, slightly sticky and slightly plastic; few to common, very fine<br />
to fine roots; clear and wavy transition to<br />
yellowish brown (IOYR5/6); very gravelly, slightly stony clay; few to<br />
frequ<strong>en</strong>t, small to large, hard irregular to spherical iron concretions; weak<br />
fine to medium subangular blocky; firm, slightly sticky and slightly plastic;<br />
few to many, fine to medium roots; gradual and smooth transition to<br />
strong brown (7.5YR5/8); very gravelly, slightly stony clay; few (5%)<br />
medium faint diffuse 5YR5/8 monies; few to very frequ<strong>en</strong>t, small to large,<br />
hard irregular to angular iron concretions; weak fine subangular blocky;<br />
firm, slightly sticky and slightly plastic; no roots.<br />
Horizon<br />
Ah<br />
BA<br />
Bws<br />
Bel<br />
Bel<br />
Be2<br />
Horizon<br />
Ah<br />
BA<br />
Bws<br />
Bel<br />
Bel<br />
Be2<br />
Horizon<br />
Ah<br />
BA<br />
Bws<br />
Bel<br />
Bel<br />
Be2<br />
Depth (cm)<br />
Pr<strong>of</strong>ile 71<br />
Particle size distribution % <strong>of</strong> fine<br />
earth; in I'm<br />
pH<br />
PROFILE 76<br />
Leg<strong>en</strong>d unit:<br />
Soil classification:<br />
Description:<br />
Location:<br />
Elevation:<br />
Landform and slope:<br />
Par<strong>en</strong>t material:<br />
Vegetation:<br />
Drainage:<br />
Soil:<br />
Depth (cm)<br />
0- 7<br />
7- 16<br />
16- 42<br />
42-250<br />
Am<br />
Xanthic Ferralsol (FAO)<br />
Typic Hapludox (Soil Taxonomy)<br />
On 27-04-95 by Gerard Hazeu<br />
About 4 km SE <strong>of</strong> Bityili village; 2°56'06 Nand 10°49'55 E<br />
800 m<br />
Mountains; upper slope 30%<br />
Gneisses and/or diorite <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Forest<br />
Well drained<br />
Very deep, yellowish brown to strong brown clay<br />
Hor.<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Description<br />
dark brown (7.5YRJ/3); clay; strong fine granular to subangular<br />
bloc!,:y; friable, slightly sticky and slightly plastic; common very<br />
fine to fine roots; clear and smooth transition to<br />
dark brown to brown (7.5YR4/3); clay; strong fine granular to<br />
subangular blocky; friable, slightly sticky and slightly plastic;<br />
common fine to medium roots; clear and smooth transition to<br />
strong brown (7.5YR5/6); clay; moderate fine to medium<br />
subangular bloc!,:y; friable, slightly stick), and slightly plastic; few<br />
to common, fine to medium roots; diffuse and smooth transition<br />
to<br />
strong brown (7.5YR517); clay; very few «5%) fine faint diffuse<br />
5YR5/8 mottles; moderate, fine to medium subangular blocky;<br />
friable, slightly sticky and slightly plastic; few very fine to fine<br />
roots.<br />
Horizon Depth (cm)<br />
Pr<strong>of</strong>ile 76<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in J.lm<br />
pH<br />
PROFILE 123<br />
Leg<strong>en</strong>d unit: Bh2<br />
Soil classification: Xanthic Ferralsol (FAO)<br />
Typic lIapludox (Soil Taxonomy)<br />
Description:<br />
On 16-06-95 by Gerard Hazeu<br />
Location:<br />
About 400 m N <strong>of</strong> Mebanga village; 2°48'64 Nand 10°37'87 E<br />
Elevation:<br />
590 m<br />
Landforrn and slope: Complex <strong>of</strong> hills; upper slope 40%<br />
Par<strong>en</strong>t material: Gneisses <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Secondary forest<br />
Drainage:<br />
Well drained<br />
Soil:<br />
Very deep, yellowish brown to strong brown clay<br />
Depth (cm)<br />
0- S<br />
5- 16<br />
16- 54<br />
54-119<br />
119-210<br />
Hor.<br />
Description<br />
Ah dark yellowish brown (I OYR3/4); clay; strong, very fine to fine crumb to<br />
subangular blocky; friable, slightly sticky and slightly plastic; common<br />
very fine to fine roots; clear and smooth transition to<br />
BA dark yellowish brown (I OYR4/6); clay; strong very fine to fine subangular<br />
blocky; friable, slightly sticky and slightly plastic; patchy thick clay<br />
cutans; few to common, very fine to medium roots; gradual and smooth<br />
transition to<br />
Bwsl strong brown (7.SYR5/6); clay; moderate very fine to fine subangular<br />
blocky; friable, slightly sticky and slightly plastic; patchy thick clay<br />
cutans; few to common, fine to medium roots; gradual and smooth<br />
transition to<br />
Bws2 strong brown (7.SYRS/8); clay; weak to moderate, very fine to fine<br />
subangular blocky; friable, slightly sticky and slightly plastic; very few to<br />
few, fine to medium roots; diffuse and smooth transition to<br />
Bws3 strong brown (7.SYRS/8); clay; very few «2%) very fine fresh gravels;<br />
weak to moderate, very fine to fine subangular blocky; friable, slightly<br />
sticky and slightly plastic; very few fine to medium roots.<br />
Horizon Depth (cm)<br />
Pr<strong>of</strong>ile 123<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in flm<br />
pH<br />
-.0<br />
00<br />
PROFILE 132<br />
Leg<strong>en</strong>d unit: Bh2<br />
Soil classification: Acri-xanthic Ferralsol (FAO)<br />
Typic Kandiudox (Soil Taxonomy)<br />
Description:<br />
On 16-06-95 by Gerard Hazeu<br />
Location:<br />
About 300 m N <strong>of</strong> Mebanga village; Z048'64 Nand 10°37'87 10°37'87 E<br />
Elevation:<br />
540 540 m<br />
Landfoml and slope: Complex <strong>of</strong> hills; middle slope 25%<br />
Par<strong>en</strong>t material: Gneisses <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Secondary forest<br />
Drainage:<br />
Well drained<br />
Soil:<br />
Very deep, yellowish brown to strong brown clay<br />
Depth (cm)<br />
0- 5<br />
5- 12<br />
12- 12- 27<br />
27- 84<br />
84-122 84-122<br />
122-190 122-190<br />
Ilor.<br />
Description<br />
Ah dark yellowish brown (lOYR3/4); sandy clay; weak to moderate, very fine<br />
to fine crumb to subangular blocky; friable, slightly sticky and and slightly<br />
plastic; many very fine to fine roots; clear and smooth transition to<br />
BA dark yellowish brown (lOYR3/6); clay; weak to moderate, very fine to fine<br />
sub angular blocky; friable, slightly sticky and slightly plastic; few to many,<br />
very fine to fine line roots; clear and smooth transition to<br />
Bwsl strong brown (7.5YR517); clay; weak to moderate, very fine to fine<br />
sub angular blocky; friable, slightly stick), and slightly plastic; patchy thick<br />
clay cutans; few fine to medium roots; gradual and smooth transition to<br />
Bws2 strong brown (7.5YR5/8); clay; weak to moderate, very fine to fine<br />
subangular blocky; friable, slightly sticky and slightly plastic; patchy thick<br />
clay cutans; very few to few, very fine to fine roots; diffuse and smooth<br />
transition to<br />
Bws3 strong brown (7.5YR5/8); clay; very few «5%) fine fine faint diffuse 5YR5/6<br />
mottles; mottles; weak very fine to fine fine subangular blocky; friable, slightly slightly sticky<br />
and slightly plastic; patchy thick clay cutans; very few very fine to fine<br />
roots; diffuse and smooth transition to<br />
Bws4 strong brown (7.5YR5/8); (7.5YR5/8); clay; many fine faint diffuse 2.5YR5/6 mottles;<br />
very few «2%) very fine fresh gravels; weak very fine to fine subangular<br />
blocky; friable, slightly sticky and slightly plastic; very few very fine to<br />
fine roots.<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Bws3<br />
Bws4<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Bws3<br />
Bws4<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Bws3<br />
Bws4<br />
Depth (cm)<br />
Pr<strong>of</strong>ile 132<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in Ilm<br />
pH<br />
PROFILE 134<br />
Leg<strong>en</strong>d unit:<br />
Soil classification:<br />
Description:<br />
Location:<br />
Elevation:<br />
Landfonn and slope:<br />
Par<strong>en</strong>t material:<br />
Vegetation:<br />
Drainage:<br />
Soil:<br />
Depth (cm) Hor.<br />
0- 6 Ah<br />
\0 6- 14 BA<br />
\0<br />
14- 50 Bwsl<br />
50- 651120 Bws2<br />
65/120-175 BC<br />
Bhl<br />
Ferralic Cambisol (FAO)<br />
Oxic Dystropept (Soil Taxonomy)<br />
On 24-06-95 by Gerard Hazeu<br />
About 3 km N <strong>of</strong> Ess<strong>en</strong>g village; 2°49'75 N and 10°39'53 E<br />
690 m<br />
Isolated hill; summit 0-5%<br />
Gneisses <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Forest<br />
Well drained<br />
Very yellowish brown to strong brown clay<br />
Description<br />
dark brown (7.5YR3/4); clay; moderate to strong, fine crumb to subangular<br />
blocJ.,;y; very friable, slightly stid.), and slightly plastic; abundant very fine<br />
to fine roots; clear and smooth transition to<br />
strong brown (7.5YR5/6); clay; moderate to strong, fine crumb to<br />
subangular block)'; friable, slightly sticky and slightly plastic; common to<br />
many, fine to medium roots; gradual and smooth transition to<br />
strong brown (10-7 .5YR5/8); clay; weak to moderate, fine subangular<br />
blocky; friable, slightly sticky and slightly plastic; very few to common,<br />
fine to medium roots; gradual and smooth transition to<br />
strong brown (1O-7.5YR5/8); very gravelly, stony clay; frequ<strong>en</strong>t small hard<br />
angular to spherical iron concretions; weak to moderate, fine to medium<br />
subangular blocky; friable, slightly sticky and slightly plastic; very few to<br />
common, very fine to fine roots; gradual and brok<strong>en</strong> transition to<br />
strong brown (1O-7.SYRS/8); stony, very bouldery clay; weak fine<br />
subangular blocky; friable, slightly sticky and slightly plastic; no roots.<br />
Horizon<br />
Ab<br />
BA<br />
Bwsl<br />
Bws2<br />
BC<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
BC<br />
Horizon<br />
Ab<br />
BA<br />
Bwsl<br />
Bws2<br />
BC<br />
Depth (cm)<br />
Pr<strong>of</strong>ile 134<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in I'm<br />
pH<br />
o<br />
o<br />
PROFILE 214<br />
Leg<strong>en</strong>d unit: Bh2<br />
Soil classification: Ferralic Cambisol (FAO)<br />
Oxic Dystropept (Soil Taxonomy)<br />
Description:<br />
On 12-08-95 by Gerard Hazeu<br />
Location:<br />
About I km S <strong>of</strong>Ma'am<strong>en</strong>yin village; 3°03'58 Nand 10°46'42 E<br />
Elevation:<br />
580 m<br />
Landforrn and slope: Complex <strong>of</strong> hills; summit, upper slope 25 - 30%<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material: Gneisses Gneisses <strong>of</strong> <strong>the</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Forest<br />
Drainage:<br />
Well drained<br />
Soil:<br />
Moderately deep, yellowish brown clay with sandy clay clay loam to to<br />
sandy clay topsoil<br />
Depth (cm)<br />
0- 6<br />
6-17<br />
17-55/63<br />
Hor.<br />
Description<br />
Ah dark brown (lOYR3/3); sandy clay; moderate to strong, very fine to fine<br />
crumb to subangular blocky; very friable, slightly sticky and slightly<br />
plastic; common to many, fine to medium roots; clear and smooth<br />
transition to<br />
BA dark yellowish brown (lOYRJ/6); clay; moderate to strong, very fine<br />
subangular blocky; friable, slightly sticky and slightly plastic; few to<br />
common, very fine to fine roots; clear and smooth transition to<br />
Bws yellowish brown (lOYR5/6); clay; moderate very fine to fine subangular<br />
blocky; friable, slightly sticky and slightly plastic; common very fine to<br />
fine roots.<br />
Horizon<br />
Ah<br />
BA<br />
Bws<br />
C<br />
Horizon<br />
Ah<br />
BA<br />
Bws<br />
C<br />
Horizon<br />
Ah<br />
BA<br />
Bws<br />
C<br />
Depth (cm)<br />
Pr<strong>of</strong>ile 214<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in J.lm<br />
pH<br />
o<br />
PROFILE 215<br />
Leg<strong>en</strong>d unit: Bh2<br />
Soil classification: Acri·xanthic Ferralsol (FAO)<br />
Typic Kandiudox (Soil Taxonomy)<br />
Description:<br />
On 12·08·95 by Gerard Hazeu<br />
Location:<br />
About I km S <strong>of</strong> Ma'am<strong>en</strong>yin village; 3°03'58 Nand 10°46'42 E<br />
Elevation:<br />
545 m<br />
Landfonn and slope: Complex <strong>of</strong> hills; upper slope 35 ·40%<br />
Par<strong>en</strong>t material: Gneisses <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Forest<br />
Drainage:<br />
Well drained<br />
Soil:<br />
Very deep, yellowish brown clay with sandy clay loam to sandy clay<br />
topsoil<br />
Depth (cm)<br />
o· 7<br />
7· 22<br />
22· 98<br />
98·200<br />
Hor.<br />
Description<br />
Ah dark yellowish brown (lOYRJ/4); sandy clay; moderate very fine crumb<br />
to sub angular block)'; very friable, slightly sticky and slightly plastic; very<br />
few to many, tine to coarse roots; clear and smooth transition to<br />
BA dark yellowish brown (IOYR4/6); sandy clay; moderate very fine to fine<br />
subangular blocky; friable, slightly sticky and slightly plastic; few to<br />
common, very fine to medium roots; clear and smooth transition to<br />
Bwsl yellowish brown (lOYR5/7); clay; many (20%) fine to medium, distinct<br />
diffuse 5YR5/8 mottles; weak to moderate, very fine to fine subangular<br />
blocky; friable, slightly sticky and slightly plastic; few to common, very<br />
fine to fine roots; gradual and smooth transition to<br />
Bws2 yellowish brown (IOYR5/8); clay; many (50%) fine to medium, distinct<br />
diffuse 5YR5/8 mottles; weak to moderate, very fine subangular blocky;<br />
friable, slightly sticky and slightly plastic; few very fine roots.<br />
Horizon<br />
Ah<br />
BA<br />
Bws1<br />
Bws2<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Depth (cm)<br />
Pr<strong>of</strong>ile 215<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in Ilm pH<br />
o<br />
N<br />
PROFILE 253<br />
Leg<strong>en</strong>d unit: Am<br />
Soil classification: Ferralic Cambisol (FAO)<br />
Oxic Dystropept (Soil Taxonomy)<br />
Description:<br />
On 11-01-96 by Gerard Hazeu<br />
Location:<br />
About 8 km S <strong>of</strong> Meka'all village; 2°56'91 Nand 10°41'59 E<br />
Elevation:<br />
Unknown<br />
Landforrn and slope: Mountains; summit, upper slope 10%<br />
Par<strong>en</strong>t material: Gneisses and/or diorite <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Forest<br />
Drainage:<br />
Well drained<br />
Soil:<br />
Very deep, yellowish brown to strong brown clay<br />
Depth (cm)<br />
0- 5<br />
5- 13<br />
13- 55<br />
55-185<br />
1I0r.<br />
Description<br />
Ah dark brown dark yellowish brown (IOYRJ/6); clay loam; moderate to<br />
strong, very fine to fine crumb to subangular blod:y; loose, friable, slightly<br />
stid.,), and slightly plastic; many to abundant, very fine to fine roots; clear<br />
and smooth transition to<br />
BA dark yellowish brown (IOYR4/6); (I OYR4/6); sandy clay; moderate to strong, very fine<br />
to fine crumb to subangular blocky; s<strong>of</strong>t, friable, slightly sticky and<br />
slightly plastic; common to many, fine to medium roots; clear and smooth<br />
transition to<br />
Bwsl yellowish brown (lOYR5/8); (lOYR5/8); clay; very few «5%) small hard spherical<br />
iron concretions; moderate to strong, very fine to fine subangular blocky;<br />
friable, slightly sticky and slightly plastic; few, medium to coarse roots;<br />
gradual and smooth transition to<br />
Bws2 strong brown (7.5YR5/8); (7.5YR5/8); clay; moderate to strong, very fine to fine<br />
subangular blocky; friable, slightly sticky and slightly plastic; few very<br />
fine to fine roots.<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Bws2<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Bws2<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Bws2<br />
Depth (cm)<br />
Pr<strong>of</strong>ile 253<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in pm<br />
pH<br />
PROFILE 254<br />
Leg<strong>en</strong>d unit:<br />
Soil classification:<br />
Description:<br />
Location:<br />
Elevation:<br />
Landform and slope:<br />
Par<strong>en</strong>t material:<br />
Vegetation:<br />
Drainage:<br />
Soil:<br />
Depth (cm) /lor.<br />
0- 7 Ah<br />
0 7- 44 BA<br />
w<br />
44-132 Bwsl<br />
132- 210 Bws2<br />
Am<br />
Ferralic Cambisol (FAO)<br />
Oxic Dystropept (Soil Taxonomy)<br />
On 11-01-96 by Gerard Hazeu<br />
About 8 km S <strong>of</strong> Meka'all village; r56'91 Nand 10°41'59 E<br />
Unknown<br />
Mountains; upper slope 70 - 80%<br />
Gneisses and/or diorite <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Forest<br />
Well drained<br />
Very deep, yellowish brown to strong brown sandy clay<br />
Description<br />
strong brown (7.5YR4/6); sandy clay loam; moderate to strong, medium<br />
crumb to granular; loose, friable, slightly sticky and slightly plastic;<br />
common to abundant, fine to medium roots; clear and smooth transition to<br />
strong brown (7.5YR516); sandy clay; moderate to strong, medium crumb<br />
to subangular block],; loose, friable, slightly stick], and slightly plastic; few<br />
to common, fine to coarse roots; gradual and irregular transition to<br />
strong brown (7.5YR5/8); sandy clay; moderate fine to medium crumb to<br />
subangular blocky; friable, slightly sticky and slightly plastic; few, very<br />
fine to fine roots; gradual and smooth transition to<br />
strong brown (7.5YR5/8); siightly gravelly clay; few small hard spherical<br />
iron concretions; moderate fine to medium subangular blocky; friable,<br />
slightly sticky and slightly plastic; few very fine to fine roots.<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Depth (cm)<br />
Pr<strong>of</strong>ile 254<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in pm<br />
pH<br />
o<br />
+>-<br />
PROFILE 255 255<br />
Leg<strong>en</strong>d unit: Am<br />
Soil classification: Ferric Acrisol (FAO)<br />
Typic Typic Hapludult (Soil Taxonomy) Taxonomy)<br />
Description:<br />
On 11-01-96 by Gerard Hazeu<br />
Location:<br />
About 8 km S <strong>of</strong> Meka'all village; 2"S6'91 Nand 10041'S9 E<br />
Elevation:<br />
Unknown<br />
Landforrn and slope: Mountains; middle slope 30 - 40%<br />
Par<strong>en</strong>t material: Gneisses and/or diorite <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Forest<br />
Drainage:<br />
Moderately well drained<br />
Soil:<br />
Deep, yellowish brown to strong brown<br />
Depth (cm)<br />
0- 7<br />
7-18<br />
18-40<br />
40-60/80<br />
60/80-125<br />
Hor.<br />
Description<br />
All dark yellowish brown (IOYR3/6); (I0YR3/6); slightly gravelly loam; moderate fine<br />
crumb to angular blocky; loose, friable, slightly sticky and slightly plastic;<br />
lew few to common, fine fine to medium roots; clear and smooth transition to<br />
BA dark yellowish brown (IOYR4/6); clay loam; weak to moderate, fine<br />
angular to subangular blocky; friable, slightly sticky and slightly plastic;<br />
few fine to medium roots; gradual and smooth transition to<br />
Bwsl yellowish brown (IOYRS/6); (I0YRS/6); slightly gravelly clay loam; few small hard<br />
spherical iron concretions; weak to moderate fine angular to subangular<br />
bloc).,.]'; blod:y; friable, slightly sticky and slightly plastic; very few to few, fine to<br />
coarse roots; gradual and smooth transition to<br />
Bc yellowish brown (IOYRS/6); gravelly clay loam; few to frequ<strong>en</strong>t, small to<br />
large, s<strong>of</strong>t to hard, irregular to spherical iron concretions; weak to moderate<br />
fine angular to sub angular blocky; friable, slightly sticky and slightly<br />
plastic; very few very fine roots; gradual and irregular transition to<br />
BC yellowish brown (IOYRS/8); gravelly, slightly stony, slightly bouldery clay<br />
loam; few (S%) fine distinct clear SYRS/8 mottles; frequ<strong>en</strong>t small s<strong>of</strong>t<br />
irregular to angular iron concretions; weak fine angular to subangular<br />
blocky; friable, slightly sticky and slightly plastic; no roots.<br />
Horizon Depth (cm)<br />
Pr<strong>of</strong>ile 255<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in I'm<br />
pH<br />
e><br />
0\<br />
IV.B Ebom soil type<br />
PROFILE 133<br />
Leg<strong>en</strong>d unit:<br />
Soil classification:<br />
Description:<br />
Location:<br />
Elevation:<br />
Landfonn and slope:<br />
Par<strong>en</strong>t material:<br />
Vegetation:<br />
Drainage:<br />
Soil:<br />
Depth (cm) Hor.<br />
0- 0- 10 Ah<br />
10- 21 BA<br />
21- 50 Bwsl<br />
50- 78 Bws2<br />
78-114 BC<br />
Cui<br />
Acri-xanthic Ferralsol (FAO)<br />
Typic Kandiudult (Soil Taxonomy)<br />
On 16-06-95 by Gerard Hazeu<br />
About About 100 m N <strong>of</strong> Mebanga village; r48'64 Nand 10°37'87 E<br />
500 m<br />
Undulating to rolling uplands; lower slope 5%<br />
Gneisses <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Agricultural field<br />
Well drained<br />
Deep, yellowish brown clay with sandy loam topsoil<br />
Description<br />
dark yellowish brown (IOYR3/4); sandy loam; weak very fine crumb;<br />
loose, non sticky and slightly plastic; many very fine to fine roots; clear<br />
and smooth transition to<br />
dark yellowish brown (IOYR4/6); sandy clay; weak to moderate, very fine<br />
to fine sub angular blocky; friable, slightly sticky and slightly plastic;<br />
common very fine to fine roots; gradual and smooth transition to<br />
yellowish brown (IOYR5/6); slightly gravelly clay; weak to moderate, very<br />
fine to fine fine subangular blocky; friable, slightly sticky and and slightly plastic;<br />
few very fine to fine roots; clear and and smooth transition to<br />
yellowish brown (I0YRS/6); gravelly clay; few small to large, hard<br />
irregular iron concretions; weak to moderate, very fine to fine subangular<br />
blocky; friable, slightly slightly sticky and slightly plastic; no roots; gradual and<br />
smooth transition to<br />
yellowish brown (I (IOYR5/6); OYR5/6); gravelly to very gravelly clay; frequ<strong>en</strong>t small<br />
to large, s<strong>of</strong>t to hard hard irregular iron concretions; weak to moderate, very fine<br />
to fine subangular blocky; friable, slightly sticky and slightly plastic; no<br />
roots.<br />
Horizon Depth (cm)<br />
Pr<strong>of</strong>ile 133<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in I'm<br />
pH<br />
0<br />
-...l<br />
PROFILE 135<br />
Leg<strong>en</strong>d unit:<br />
Soil classification:<br />
Description:<br />
Location:<br />
Elevation:<br />
Landform and slope:<br />
Par<strong>en</strong>t material:<br />
Vegetation:<br />
Drainage:<br />
Soil:<br />
Depth (cm) Bor.<br />
0- 7 Ah<br />
7- 25 BA<br />
25-40/130 BwsI<br />
40-130 Bws2<br />
Bhl<br />
Acri-xanthic Ferralsol (FAO)<br />
Typic Kandiudult (Soil Taxonomy)<br />
On 24-06-95 by Gerard Hazeu<br />
About 3 km N <strong>of</strong>Ess<strong>en</strong>g village; 2°49'75 Nand 10°39'53 E<br />
5S0 m<br />
Isolated hill; lower slope 25%<br />
Gneisses <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Forest<br />
Well drained<br />
Moderately deep to deep, yellowish brown to strong brown clay with sandy<br />
clay loam to sandy clay topsoil<br />
Description<br />
dark yellowish brown (I OYR4/4); sandy clay loam; strongly coher<strong>en</strong>t; very<br />
friable, slightly sticky and slightly plastic; few very fine roots; clear and<br />
smooth transition to<br />
yellowish brown (I0YR4/6); clay; weak to moderate, fine subangular<br />
block)'; friable, slightly sticky and slightly plastic; common to many, very<br />
fine to fine roots; clear and smooth transition to<br />
yellowish brown (IOYR5/S); clay; weak, fine subangular blocky; friable,<br />
slightly stick), and slightly plastic; very few to few, fine to medium roots;<br />
abrupt and brok<strong>en</strong> transition to C and gradual and smooth to Bws2<br />
yellowish brown (IOYR5/S); slightly gravelly clay; few (5%) fine distinct<br />
clear 7.5YR5/S mottles; weak fine subangular blocky; friable, slightly<br />
sticky and slightly plastic; very few to few, fine to medium roots.<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
C(B)<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
C(B)<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
C(B)<br />
Depth (cm)<br />
Pr<strong>of</strong>ile 135<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in i'm pH<br />
o o<br />
00 00<br />
PROFILE PROFILE 140 140<br />
Leg<strong>en</strong>d unit:<br />
Soil classification: Plinthic Axrisol (FAO)<br />
Typic PlinthuduIt (Soil Taxonomy)<br />
Description:<br />
Location:<br />
About S km NE <strong>of</strong> Adjap village; 2°55'99 Nand 10°37'29 E<br />
Elevation:<br />
Landform and slope: Undulating to rolling uplands; upper slope 5 - 10%<br />
Par<strong>en</strong>t material: Gneisses and/or migmatites <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Forest<br />
Drainage:<br />
Moderately well drained<br />
Soil:<br />
clay loam topsoil<br />
Leg<strong>en</strong>d unit: DuI<br />
Soil classification: Plinthic Axrisol (FAO)<br />
Typic PlinthuduIt (Soil Taxonomy)<br />
Description:<br />
On 27-06-95 by Gerard Hazeu<br />
Location:<br />
About 8 km NE <strong>of</strong> Adjap village; 2°55'99 Nand 10°37'29 E<br />
Elevation:<br />
Landform and slope: Undulating to rolling uplands; upper slope 5 - 10%<br />
Par<strong>en</strong>t material: Gneisses and/or migmatites <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Forest<br />
Drainage:<br />
Moderately well drained<br />
Soil:<br />
Very deep, yellowish brown sandy clay to clay with sandy loam to sandy<br />
clay loam topsoil<br />
Depth (cm)<br />
Depth (cm)<br />
0- 0- 7 7<br />
7- 17<br />
7- 17<br />
17- 35<br />
17- 35<br />
35- 72<br />
35- 72<br />
72-170<br />
72-170<br />
Hor.<br />
Hor.<br />
Ah<br />
Ah<br />
DuI<br />
On 27-06-95 by Gerard Hazeu<br />
350m 350m<br />
Very deep, yellowish brown sandy clay to clay with sandy loam to sandy<br />
Description<br />
Description<br />
dark brown to brown (IOYR4/3); sandy loam; weak to moderate, very fine<br />
dark brown to brown (IOYR4/3); sandy loam; weak to moderate, very fine<br />
to fine crumb to subangular blocky; very friable, slightly sticky and<br />
slightly plastic; few to common, fine to coarse roots; clear and smooth<br />
transition to<br />
to fine crumb to subangular blocky; very friable, slightly sticky and<br />
slightly plastic; few to common, fine to coarse roots; clear and smooth<br />
transition to<br />
BA BA dark dark yellowish yellowish brown brown (IOYR4/6); (I0YR4/6); sandy sandy clay clay loam; loam; weak weak fine fine subangular subangular<br />
blod:y; friable, slightly stick]' and slightly plastic; few to common, fine to<br />
medium roots; clear and smooth transition to<br />
Bwsl yellowish brown (IOYR5/6); slightly gravelly sandy clay loam; very few<br />
bloc!,.-y; friable, slightly stic!"-y and slightly plastic; few to common, fine to<br />
medium roots; clear and smooth transition to<br />
Bwsl yellowish brown (I0YR5/6); slightly gravelly sandy clay loam; very few<br />
small hard spherical iron concretions; weak to moderate, very fine to fine<br />
subangular blocky; friable, slightly sticky and slightly plastic; few to<br />
common, very fine to fine roots; gradual and smooth transition to<br />
Bws2 brownish yellow (I OYR6/6); gravelly sandy clay; very few to few, small<br />
small hard spherical iron concretions; weak to moderate, very fine to fine<br />
subangular blocky; friable, slightly sticky and slightly plastic; few to<br />
common, very fine to fine roots; gradual and smooth transition to<br />
Bws2 brownish yellow (I OYR6/6); gravelly sandy clay; very few to few, small<br />
to to large, large, hard hard angular angular to to spherical spherical iron iron concretions; concretions; weak weak to to moderate, moderate, very very<br />
fine to fine subangular blocky; friable, slightly stick], and slightly plastic;<br />
fine to fine subangular blocky; friable, slightly stic!,.-y and slightly plastic;<br />
few very fine to fine roots; gradual and irregular transition to<br />
Bv yellow (2.5Y7/8); very gravelly sandy clay; many (25%) medium<br />
promin<strong>en</strong>t diffuse IOYR4/8 and I OYR 7 18 mottles; few small to large, s<strong>of</strong>t<br />
few very fine to fine roots; gradual and irregular transition to<br />
Bv yellow (2.5Y7/S); very gravelly sandy clay; many (25%) medium<br />
promin<strong>en</strong>t diffuse IOYR4/S and IOYR7/S mottles; few small to large, s<strong>of</strong>t<br />
to to hard, hard, angular angular to to spherical spherical iron iron concretions; concretions; weak weak very very fine fine subangular subangular<br />
blocky and moderately coher<strong>en</strong>t structure; friable, slightly sticky and<br />
slightly plastic; few very fine to fine roots.<br />
blocky and moderately coher<strong>en</strong>t structure; friable, slightly sticky and<br />
slightly plastic; few very fine to fine roots.<br />
Horizon<br />
Horizon<br />
Ah<br />
Ah<br />
BA BA<br />
Bws1 Bws1<br />
Bws2<br />
Bws2<br />
Bv Bv<br />
Bv Bv<br />
Horizon<br />
Horizon<br />
Ah<br />
Ah<br />
BA<br />
Bws1<br />
Bws2<br />
BA<br />
Bws1<br />
Bws2<br />
Bv Bv<br />
Bv Bv<br />
Horizon<br />
Horizon<br />
Ah Ah<br />
BA<br />
Bws1<br />
Bws2<br />
Bv<br />
Bv<br />
BA<br />
Bws1<br />
Bws2<br />
Bv<br />
Bv<br />
Pr<strong>of</strong>ile 140<br />
Particle size distribution<br />
Depth (cm) % <strong>of</strong> fine earth; in J.lm pH<br />
Pr<strong>of</strong>ile 140<br />
Particle size distribution<br />
Depth (cm) % <strong>of</strong> fine earth; in J.lm pH<br />
0<br />
\0<br />
PROFILE 141<br />
Leg<strong>en</strong>d unit: DuI<br />
Soil classification: Acri-xanthic Ferralsol (FAO)<br />
Typic Kandiudult (Soil Taxonomy)<br />
Description:<br />
On 27-06-95 by Gerard Hazeu<br />
Location:<br />
About S km NE <strong>of</strong> Adjap village; 2°55'99 Nand 10°37'29 E<br />
Elevation:<br />
350 m<br />
Landform and slope: Undulating to rolling uplands; lower slope 10 - 15%<br />
Par<strong>en</strong>t material: Gneisses and/or migmatites <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Forest<br />
Drainage:<br />
Well drained<br />
Soil:<br />
Very deep, yellowish brown sandy clay to clay with loamy sand to sandy<br />
clay loam topsoil<br />
Depth (cm)<br />
0- 5<br />
5- 15<br />
15- 55<br />
55-136<br />
136-167<br />
167-185<br />
Hor.<br />
Description<br />
Ah dark yellowish brown (IOYRJ/4); sandy loam; weak fine crumb; very<br />
friable, non sticky and slightly plastic; common to many, very fine to<br />
medium roots; clear and smooth transition to<br />
BA dark yellowish brown (I OYRJ/6); sandy clay loam; weak to moderate, very<br />
fine to fine crumb to subangular blocky; friable, slightly sticky and slightly<br />
plastic; few very fine to fine roots; gradual and smooth transition to<br />
Bwsl yellowish brown (I OYR5/6); sandy clay; moderate very fine to fine<br />
subangular blocky; friable, slightly sticky and slightly plastic; common<br />
fine to medium roots; gradual and smooth transition to<br />
Bws2 yellowish brown (IOYR5/S); slightly gravelly sandy clay; very few (2%)<br />
fine faint diffuse 7.5YR5/S mottles; moderate very fine to fine subangular<br />
blocky; friable, slightly sticky and slightly plastic; few to common, fine to<br />
medium roots; gradual and irregular transition to<br />
Bws3 yellowish brown (IOYR5/S); gravelly sandy clay; few (10%) fine faint<br />
diffuse 7.5YR5/S mottles; few small hard spherical iron concretions; weak<br />
to moderate, very fine to fine subangular blocky; friable, slightly sticky<br />
and slightly plastic; few fme to medium roots; clear and smooth transition<br />
to<br />
Bv yellowish brown (IOYR5/8); gravelly sandy clay; many (15%) fine distinct<br />
clear 2.5YR4/S mottles; frequ<strong>en</strong>t small to large, hard angular to spherical<br />
iron concretions; weak to moderate, very fine to fine subangular blocky;<br />
friable, slightly sticky and slightly plastic; very few very fine to fine roots.<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Bws3<br />
Bv<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Bws3<br />
Bv<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
Bws3<br />
Bv<br />
Pr<strong>of</strong>ile 141<br />
Particle size distribution<br />
Depth (cm) % <strong>of</strong> fme earth; in pm<br />
pH<br />
o<br />
PROFILE 147<br />
Leg<strong>en</strong>d unit: Cui<br />
Soil classification: Acri-xanthic Ferralsol (FAO)<br />
Typic Kandiudult (Soil Taxonomy)<br />
Description:<br />
On 28-06-95 by Gerard Hazeu<br />
Location:<br />
About 8 km NE <strong>of</strong> Adjap village; 2°55'99 Nand 10°37'29 E<br />
Elevation:<br />
380 m<br />
Landform and slope: Undulating to rolling uplands; summit 0 - 5%<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: Gneisses <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Forest<br />
Drainage:<br />
Well drained<br />
Soil:<br />
Very deep, yellowish brown clay with sandy clay loam topsoil<br />
Depth Depth (cm) (cm)<br />
0- 10<br />
10- 10- 21<br />
21- 87<br />
87-160<br />
160-220<br />
Bor. Description<br />
Ah dark yellowish brown (IOYR3/4); (IOYR3/4); sandy clay loam; weak to moderate, very very<br />
fine to to fine fine subangular blocky; very very friable, slightly sticky and slightly slightly<br />
plastic; very few few to many, very fine to coarse roots; clear and smooth smooth<br />
transition to<br />
BA dark dark yellowish brown brown (IOYR3/6); (IOYR3/6); sandy clay loam; weak very fine fine to to fine<br />
subangular block}'; friable, slightly stick}' and slightly plastic; few to to many,<br />
very fine to fine fine roots; gradual and smooth transition to<br />
Bwsl yellowish brown (I0YR5/8); sandy clay; moderate very fine to fine crumb<br />
to subangular blocky; friable, slightly sticky and slightly plastic; few to<br />
common, very fine to fine roots; gradual and smooth transition to<br />
Bws2 brownish yellow (IOYR6/8); sandy clay; weak to moderate, very fine to<br />
fine crumb to sub angular blocky; friable, slightly sticky and slightly<br />
plastic; few to common, fine to medium roots; gradual and smooth<br />
transition to<br />
Bws3 brownish yellow (I0YR6/8); slightly gravelly sandy clay; weak very fine<br />
to fine crumb to subangular blocky; friable, slightly sticky and slightly<br />
plastic; few very fine to fine roots.<br />
Horizon Depth (cm)<br />
Pr<strong>of</strong>ile 147<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in I'm<br />
pH<br />
PROFILE 152<br />
Leg<strong>en</strong>d unit: Du2<br />
Soil classification: Acri-xanthic Ferralsol (FAO)<br />
Typic Kandiudult (Soil Taxonomy)<br />
Description:<br />
On 12-07-95 by Gerard Hazeu<br />
Location:<br />
About 900 m SW <strong>of</strong>Mel<strong>en</strong> village; 3°02'80 Nand 10°31'64 E<br />
Elevation:<br />
900 m<br />
Landform and slope: Rolling uplands; summit 5%<br />
Par<strong>en</strong>t material: Gneisses <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Secondary forest<br />
Drainage:<br />
Well drained<br />
Soil:<br />
Deep, yellowish brown to strong brown clay with sandy clay loam to sandy<br />
clay topsoil<br />
Depth (cm)<br />
0-3<br />
3-16<br />
16-45/65<br />
45/65-101<br />
101-130<br />
1I0r. Description<br />
Ah dark yellowish brown (IOYR4/4); sandy clay loam; strong to moderate,<br />
fine crumb to subangular blocky; slightly hard, friable, slightly sticky and<br />
slightly plastic; common very fine to fine roots; abrupt and smooth<br />
transition to<br />
BA yellowish brown (I0YR5/6); sandy clay; moderate fine subangular blocky;<br />
hard, friable, slightly sticky and slightly plastic; few to common, very fine<br />
to medium roots; gradual and smooth transition to<br />
Bwsl strong brown (7.5YR5/8); slightly gravelly clay; few (2%) fine distinct<br />
diffuse 2.5YR5/8 mottles; very few small s<strong>of</strong>t irregular iron concretions;<br />
weak to moderate, fine to medium subangular blocky; slightly hard, friable,<br />
slightly sticky and slightly plastic; very few to few, very fine to coarse<br />
roots; gradual and wavy transition to<br />
Bws2 strong brown (7.5YR5/8); gravelly clay; few (10%) fine distinct diffuse<br />
2.5YR5/8 mottles; few small hard spherical iron concretions; weak to<br />
moderate, fine angular to subangular blocky; friable, slightly sticky and<br />
slightly plastic; very few very fine roots; gradual and brok<strong>en</strong> transition to<br />
BC yellow (I0YR7/8); gravelly, bouldery clay; many (25%) medium distinct<br />
diffuse 2.5YR5/8 mottIes; few small s<strong>of</strong>t to hard, irregular to spherical iron<br />
concretions; weak to moderate, medium angular to subangular blocky;<br />
firm, slightly sticky and slightly plastic; very few very fine roots.<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
BC<br />
."<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
BC<br />
Horizon<br />
Ab<br />
BA<br />
Bwsl<br />
Bws2<br />
BC<br />
Pr<strong>of</strong>ile 152<br />
Particle size dislribulion<br />
Depth (cm) % <strong>of</strong> fine earth; in ,"m<br />
pH<br />
N<br />
PROFILE PROFILE 153<br />
Leg<strong>en</strong>d unit:<br />
Soil classification:<br />
Description:<br />
Location:<br />
Elevation:<br />
Landform and slope:<br />
Par<strong>en</strong>t material:<br />
Vegetation:<br />
Drainage:<br />
Soil:<br />
Depth (cm) 1I0r.<br />
0- 7 Ah<br />
7- 32 BA<br />
32-112 Bwsl<br />
112-150 Bws2<br />
ISO-ISO BC<br />
Du2<br />
Haplic Acrisol (FAO)<br />
Typic Kandiudult (Soil Taxonomy)<br />
On 12-07-95 by Gerard Hazeu<br />
About 900 900 m m SW <strong>of</strong> Mel<strong>en</strong> village; 3 °02'80 N and 10°31 '64 E<br />
700 m<br />
Rolling uplands; uplands; middle slope 70%<br />
Gneisses Gneisses <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Secondary forest<br />
Well drained<br />
Very deep, yellowish brown clay with sandy clay loam to sandy clay<br />
topsoil<br />
Description<br />
dark brown (lOYR3/3); clay loam; strong to moderate, fine crumb to<br />
subangular blocky; friable, slightly sticky and slightly plastic; common<br />
fine to medium roots; clear and smooth transition to<br />
dark yellowish brown (IOYR4/6); clay loam; moderate to strong, fine to<br />
medium, angular to subangular blocky; firm, slightly sticky and slightly<br />
plastic; few to many, fine to medium roots; gradual and wavy transition to<br />
yellowish brown (lOY5/8); slightly gravelly clay; moderate fine to medium<br />
angular to subangular blocky; firm, slightly sticky and slightly plastic;<br />
common very fine to fine roots; gradual and smooth transition to<br />
brownish yellow (IOYR6/8); slightly gravelly clay loam; weak very fine<br />
to fine, angular to subangular block)' and strongly coher<strong>en</strong>t porous massive<br />
structure; friable, slightly sticky and slightly plastic; very few to to few, very<br />
fine to fine roots; gradual and smooth transition to<br />
brownish yellow (IOYR6/S); sandy clay loam; weak fine subangular<br />
blocky and strongly coher<strong>en</strong>t porous massive; friable, slightly sticky and<br />
slightly plastic; no roots.<br />
Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
BC<br />
Horizon<br />
Ah Ah<br />
BA<br />
Bwsl<br />
Bws2<br />
BC<br />
Pr<strong>of</strong>ile 153<br />
Horizon Depth (cm)<br />
Particle size distribution<br />
% <strong>of</strong> fine earth; in I'm<br />
pH<br />
.j::>.<br />
PROFILE PROFILE 167<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit:<br />
Soil classification:<br />
classification:<br />
Description: Description:<br />
Location: Location:<br />
Elevation: Elevation:<br />
Landform Landform and slope: slope:<br />
Par<strong>en</strong>t material: material:<br />
Vegetation: Vegetation:<br />
Drainage: Drainage:<br />
Soil:<br />
Depth (cm) Hor.<br />
0- 6 Ah<br />
6- IS AB<br />
15- 28 BA<br />
28-118 Bwsl<br />
118-200 118-200 Bws2<br />
Cui<br />
Xanthic Xanthic Ferralsol Ferralsol (FAO)<br />
Typic Hapludox (Soil Taxonomy) Taxonomy)<br />
On 22-07-95 22-07-95 by Gerard Gerard Hazeu Hazeu<br />
About About I I km S <strong>of</strong> Ebom Ebom 11 village; village; 3"04'05 3°04'05 Nand Nand 10°42'59 10°42'59 E E<br />
370 m<br />
Undulating Undulating to rolling uplands; uplands; lower slope 10 - 15%<br />
Gneisses <strong>of</strong> <strong>the</strong> Precambrian Precambrian shield<br />
Forest<br />
Well drained<br />
Very deep, yellowish yellowish brown clay with sandy clay topsoil<br />
Description Description<br />
dark yellowish yellowish brown (lOYRYR4/4); (IOYRYR4/4); sandy clay; moderate to strong, very<br />
fine crumb to subangular subangular blocky; loose, very friable, slightly sticky and<br />
slightly plastic; common to abundant, fine to medium roots; clear and<br />
smooth transition transition to<br />
dark yellowish yellowish brown brown (IOYR4/6); (I OYR4/6); sandy sandy clay; moderate moderate very fine to fine<br />
subangular subangular blocky; friable, slightly sticky and slightly plastic; few to<br />
common, common, fine to medium medium roots; gradual gradual and smooth smooth transition transition to to<br />
yellowish yellowish brown (IOYRs/6); (lOYRs/6); clay; moderate moderate very fine to fine subangular subangular<br />
blocky; friable, slightly sticky and slightly plastic; few few to many, fine to<br />
coarse roots; gradual and smooth transition to<br />
yellowish yellowish brown (IOYRs/8); (lOYR5/8); clay; weak to moderate, very fine to fine<br />
subangular subangular blocky; friable, slightly sticky and slightly plastic; few to many,<br />
very fine to fine roots; gradual and smooth transition transition to<br />
yellowish yellowish brown brown (IOYR5/8); (IOYR5/8); clay; few (15%) (15%) fine faint diffuse diffuse 2.sYR4/8 2.5YR4/8<br />
mottles; mottles; weak to moderate, moderate, very fine to fine subangular subangular blocky; blocky; friable, friable,<br />
slightly sticky and slightly plastic; few very fine to fine roots.<br />
Horizon<br />
Ah<br />
AB<br />
BA<br />
Bwsl<br />
Bws2<br />
Horizon<br />
Ah<br />
AB<br />
BA<br />
Bwsl<br />
Bws2<br />
Horizon<br />
Ah<br />
AB<br />
BA<br />
Bwsl<br />
Bws2<br />
Pr<strong>of</strong>ile Pr<strong>of</strong>ile 167<br />
Particle size distribution distribution<br />
Depth Depth (cm) % <strong>of</strong> fine earth; in J.lm<br />
pH<br />
VI VI<br />
PROFILE PROFILE 181 181<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: unit:<br />
Soil Soil classification:<br />
classification:<br />
Description: Description:<br />
Location: Location:<br />
Elevation: Elevation:<br />
Landform Landform and and slope: slope:<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material:<br />
Vegetation: Vegetation:<br />
Drainage: Drainage:<br />
Soil: Soil:<br />
Depth Depth (cm) (cm) Hor. Hor.<br />
0- 0- 3 3 Ah Ah<br />
3- 3- 15 15 BA BA<br />
15- 15- 30 30 Bwsl Bwsl<br />
30- 30- 71 71 Bws2 Bws2<br />
71-145 71-145 Bws3 Bws3<br />
145-175 145-175 Bv Bv<br />
Cu2IDul Cu2IDul<br />
Acri-xanthic Acri-xanthic Ferralsol Ferralsol (FAO) (FAO)<br />
Typic Typic Kandiudult Kandiudult (Soil (Soil Taxonomy) Taxonomy)<br />
On On 26-07-95 26-07-95 by by Gerard Gerard Hazeu Hazeu<br />
About About 2 2 km km NE NE <strong>of</strong>Obo'otomba <strong>of</strong>Obo'otomba village; village; 3°04'11 3°04'11 Nand Nand 10°35'68 10°35'68 E E<br />
Unknown Unknown<br />
Rolling Rolling uplands; uplands; summit, summit, upper upper slope slope 10% 10%<br />
Gneisses Gneisses and/or and/or migmatites migmatites <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Precambrian Precambrian shield shield<br />
Forest Forest<br />
Well Well drained drained<br />
Deep, Deep, yellowish yellowish brown brown clay clay with with sandy sandy clay clay loam loam to to sandy sandy clay clay topsoil topsoil<br />
Description Description<br />
dark dark brown brown (IOYR3/3); (IOYR3/3); sandy sandy clay clay loam; loam; moderate moderate very very fine fine to to fine fine crumb crumb<br />
to to subangular subangular blod:y; blod:y; very very friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; few few<br />
to to abundant, abundant, very very fine fine to to medium medium roots; roots; abrupt abrupt and and smooth smooth transition transition to to<br />
dark dark yellowish yellowish brown brown (IOYR4/6); (IOYR4/6); sandy sandy clay clay loam; loam; weak weak to to moderate, moderate, fine fine<br />
angular angular to to sub sub angular angular blocky; blocky; friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic;<br />
very very few few to to common, common, fine fine to to medium medium roots; roots; gradual gradual and and wavy wavy transition transition to to<br />
yellowish yellowish brown brown (IOYR5/6); (IOYR5/6); sandy sandy clay clay to to clay; clay; moderate moderate fine fine subangular subangular<br />
blod:y; blod:y; firm, firm, slightly slightly sticky sticky and and slightly slightly plastic; plastic; very very few few to to common, common, fine fine<br />
to to medium medium roots; roots; gradual gradual and and smooth smooth transition transition to to<br />
yellowish yellowish brown brown (I0YR5/8); (I0YR5/8); slightly slightly gravelly gravelly clay; clay; very very few few small small s<strong>of</strong>t s<strong>of</strong>t<br />
irregular irregular iron iron concretions; concretions; weak weak to to moderate, moderate, fine fine subangular subangular blocky; blocky; firm, firm,<br />
slightly slightly sticky sticky and and slightly slightly plastic; plastic; few few to to common, common, fine fine to to medium medium roots; roots;<br />
gradual gradual and and smooth smooth transition transition to to<br />
yellowish yellowish brown brown (IOYR5/8); (IOYR5/8); gravelly gravelly to to very very gravelly, gravelly, slightly slightly stony stony clay; clay;<br />
few few (5%) (5%) fine fine faint faint diffuse diffuse 7.5YR5/8 7.5YR5/8 mottles; mottles; very very few few to to few, few, small small s<strong>of</strong>t s<strong>of</strong>t<br />
to to hard, hard, irregular irregular to to spherical spherical iron iron concretions; concretions; weak weak very very fine fine to to fine fine<br />
sub sub angular angular blocky; blocky; friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; few few very very<br />
fine fine roots; roots; diffuse diffuse and and smooth smooth transition transition to to<br />
yellowish yellowish brown brown (I (I OYR5/8); OYR5/8); gravelly gravelly clay; clay; few few to to frequ<strong>en</strong>t, frequ<strong>en</strong>t, small small s<strong>of</strong>t s<strong>of</strong>t to to<br />
hard, hard, irregular irregular to to spherical spherical iron iron concretions; concretions; weak weak very very fine fine to to fine fine<br />
subangular subangular blocky; blocky; friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; few few very very<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bws3 Bws3<br />
Bv Bv<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bws3 Bws3<br />
Bv Bv<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bws3 Bws3<br />
Bv Bv<br />
Pr<strong>of</strong>ile Pr<strong>of</strong>ile 181 181<br />
Particle Particle size size distribution distribution<br />
Depth Depth (cm) (cm) % % <strong>of</strong> <strong>of</strong> fine fine earth; earth; in in I'm I'm<br />
pH pH<br />
0\<br />
PROFILE PROFILE 182<br />
Leg<strong>en</strong>d unit: Cu2/Dul<br />
Soil classification: Haplic Acrisol (FAO)<br />
Typic Paleudult (Soil Taxonomy)<br />
Description:<br />
Location:<br />
About 2 km NE <strong>of</strong>Obo'otomba village; 3°04'11 Nand 10°35'68 E<br />
Elevation:<br />
Unknown<br />
Landform and slope: Undulating to rolling uplands; middle slope 20 - 25%<br />
Par<strong>en</strong>t material: Gneisses and/or migmatites <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Forest<br />
Drainage:<br />
Moderately well drained<br />
Soil:<br />
Very deep, yellowish brown clay with sandy clay loam to sandy clay<br />
topsoil<br />
Leg<strong>en</strong>d unit: Cu2/Dul<br />
Soil classification: Haplic Acrisol (FAO)<br />
Typic Paleudult (Soil Taxonomy)<br />
Description:<br />
On 26-07-95 by Gerard Hazeu<br />
Location:<br />
About 2 km NE <strong>of</strong>Obo'otomba village; 3°04'11 Nand 10°35'68 E<br />
Elevation:<br />
Unknown<br />
Landform and slope: Undulating to rolling uplands; middle slope 20 - 25%<br />
Par<strong>en</strong>t material: Gneisses and/or migmatites <strong>of</strong> <strong>the</strong> Precambrian shield<br />
Vegetation:<br />
Forest<br />
Drainage:<br />
Moderately well drained<br />
Soil:<br />
Very deep, yellowish brown clay with sandy clay loam to sandy clay<br />
topsoil<br />
Depth (cm)<br />
Depth (cm)<br />
0- 2<br />
2- 12<br />
2- 12<br />
12- 32<br />
12- 32<br />
32-130<br />
32-130<br />
130-170<br />
130-170<br />
Hor.<br />
Hor.<br />
On 26-07-95 by Gerard Hazeu<br />
Description<br />
Description<br />
Ah brown brown (I (I OYR5/3); OYR5/3); 10anlY 10anlY sand; sand; weakly weakly coher<strong>en</strong>t coher<strong>en</strong>t single single grain; grain; loose loose to to very very<br />
friable, non sticky and slightly plastic; few fine to medium roots; clear and<br />
smooth transition to<br />
friable, non sticky and slightly plastic; few fine to medium roots; clear and<br />
smooth transition to<br />
BA yellowish yellowish brown brown (lOYR5/6); (IOYR5/6); sandy sandy clay clay loam; loam; weak weak very very fine fine to to fine fine<br />
subangular blocky; very friable, slightly sticky and slightly plastic; few<br />
subangular blocky; very friable, slightly sticky and slightly plastic; few<br />
fine to medium roots; clear and smooth transition to<br />
Bwsl brownish yellow (lOYR6/8); very gravelly sandy clay; many (15%) fine<br />
faint diffuse 7.5YR5/8 mottles; frequ<strong>en</strong>t small to large, hard irregular to<br />
angular iron concretions; weak very fine to fine subangular blocky; friable,<br />
slightly sticky and slightly plastic; few fine to medium roots; diffuse and<br />
irregular transition to<br />
fine to medium roots; clear and smooth transition to<br />
Bwsl brownish yellow (lOYR6/8); very gravelly sandy clay; many (15%) fine<br />
faint diffuse 7.5YR5/8 mottles; frequ<strong>en</strong>t small to large, hard irregular to<br />
angular iron concretions; weak very fine to fine subangular blocky; friable,<br />
slightly sticky and slightly plastic; few fine to medium roots; diffuse and<br />
irregular transition to<br />
Bv brownish brownish yellow yellow (IOYR6/8); (lOYR6/8); gravelly, gravelly, slightly slightly stony stony clay; clay; many many (25%) (25%) fine fine<br />
distinct diffuse 7.5.YR5/8 monies; few to frequ<strong>en</strong>t, small to large, s<strong>of</strong>t to<br />
hard, irregular to angular iron concretions; weak very fine to fine<br />
subangular blocky; friable, slightly sticky and slightly plastic; few very<br />
fine to fine roots; gradual and smooth transition to<br />
distinct diffuse 7.5.YR5/8 mottles; few to frequ<strong>en</strong>t, small to large, s<strong>of</strong>t to<br />
hard, irregular to angular iron concretions; weak very fine to fine<br />
subangular block)'; friable, slightly sticky and slightly plastic; few very<br />
fine to fine roots; gradual and smooth transition to<br />
BC brownish yellow (lOYR6/8); gravelly, slightly stony clay; many (25%)<br />
medium distinct diffuse 7.5YR5/8 mottles; few to frequ<strong>en</strong>t, small to large,<br />
s<strong>of</strong>t to hard, irregular to angular iron concretions; weak very fine<br />
subangular blocky and strongly coher<strong>en</strong>t porous massive structure; friable,<br />
slightly sticky and slightly plastic; few very fine to fine roots.<br />
BC brownish yellow (IOYR6/8); gravelly, slightly stony clay; many (25%)<br />
medium distinct diffuse 7.5YR5/8 monies; few to frequ<strong>en</strong>t, small to large,<br />
s<strong>of</strong>t to hard, irregular to angular iron concretions; weak very fine<br />
subangular blocky and strongly coher<strong>en</strong>t porous massive structure; friable,<br />
slightly sticky and slightly plastic; few very fine to fine roots.<br />
Horizon<br />
Horizon<br />
Ah<br />
BA<br />
Bws<br />
Bv<br />
Bv<br />
Bv<br />
Bc<br />
Horizon<br />
Horizon<br />
Ah<br />
Ah<br />
BA<br />
Bws<br />
Bws<br />
Bv<br />
Bv<br />
Bc<br />
Horizon<br />
Horizon<br />
Ah<br />
BA<br />
Bws<br />
Bws<br />
Bv<br />
Bv<br />
Bc<br />
Bc<br />
Pr<strong>of</strong>ile 182<br />
Pr<strong>of</strong>ile 182<br />
Particle size distribution<br />
Particle size distribution<br />
Depth (cm) % <strong>of</strong> fine earth; in I'm<br />
Depth (cm) % <strong>of</strong> fine earth; in "m<br />
pH<br />
PROFILE PROFILE 201 201<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: unit: Cu2 Cu2<br />
Soil Soil classification: classification: Acri-xanthic Acri-xanthic Ferralsol Ferralsol (FAO) (FAO)<br />
Typic Typic Kandiudox Kandiudox (Soil (Soil Taxonomy) Taxonomy)<br />
Description: Description:<br />
Location: Location:<br />
About About 1.5 1.5 km km S S <strong>of</strong>Engomba <strong>of</strong>Engomba village; village; 3°04'84 3°04'84 Nand Nand 10°39'45 10°39'45 E E<br />
Elevation: Elevation:<br />
Landforrn Landforrn and and slope: slope: Rolling Rolling uplands; uplands; summit, summit, upper upper slope slope 10 10 -- 15% 15%<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material: Gneisses Gneisses <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Prccambrian Prccambrian shield shield<br />
Vegetation: Vegetation:<br />
Forest Forest<br />
Drainage: Drainage:<br />
Soil: Soil:<br />
Very Very deep, deep, yellowish yellowish brown brown clay clay with with sandy sandy clay clay loam loam to to sandy sandy clay clay<br />
topsoil topsoil<br />
Depth Depth (cm) (cm)<br />
0- 0- 5 5<br />
5- 5- 18 18<br />
18- 18- 61 61<br />
61- 61- 95 95<br />
95-152 95-152<br />
152-185 152-185<br />
Hor. Hor.<br />
On On 10-08-95 10-08-95 by by Gerard Gerard Hazeu Hazeu<br />
390m 390m<br />
Well Well drained drained<br />
Description Description<br />
Ah Ah very very dark dark brown brown (7.5YR2.5/3); (7.5YR2.5/3); sandy sandy clay clay loam; loam; moderate moderate to to strong, strong, very very<br />
fine fine to to fine fine crumb crumb to to subangular subangular blocky; blocky; very very friable, friable, slightly slightly sticky sticky and and<br />
slightly slightly plastic; plastic; common common to to many, many, very very fine fine to to fine fine roots; roots; clear clear and and smooth smooth<br />
transition transition to to<br />
BA BA dark dark yellowish yellowish brown brown (I (I OYR4/6); OYR4/6); sandy sandy clay clay to to clay; clay; moderate moderate to to strong, strong,<br />
very very fine fine to to fine fine crumb crumb to to subangular subangular blocky; blocky; friable, friable, slightly slightly sticky sticky and and<br />
slightly slightly plastic; plastic; few few to to common, common, fine fine to to coarse coarse roots; roots; clear clear and and smooth smooth<br />
transition transition to to<br />
Bws Bws I I yellowish yellowish brown brown (IOYR5/6); (IOYR5/6); clay; clay; moderate moderate very very fine fine to to fine fine subangular subangular<br />
blod;y; blod;y; friable, friable, slightly slightly stick), stick), and and slightly slightly plastic; plastic; few few to to common, common, fine fine to to<br />
medium medium roots; roots; gradual gradual and and wavy wavy transition transition to to<br />
Bws2 Bws2 yellowish yellowish brown brown (IOYR5/8); (IOYR5/8); slightly slightly gravelly gravelly clay; clay; few few small small hard hard<br />
spherical spherical iron iron concretions; concretions; weak weak to to moderate, moderate, fine fine to to medium medium subangular subangular<br />
blocky; blocky; friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; very very few few to to few, few, very very<br />
fine fine to to fine fine roots; roots; gradual gradual and and wavy wavy transition transition to to<br />
Bws3 Bws3 yellowish yellowish brown brown (IOYR5/8); (IOYR5/8); slightly slightly gravelly gravelly clay; clay; very very few few «5%) «5%) fine fine<br />
distinct distinct diffuse diffuse 2.5YR4/8 2.5YR4/8 mottles; mottles; few few small small hard hard spherical spherical iron iron<br />
concretions; concretions; weak weak fine fine to to medium medium subangular subangular blocky; blocky; friable, friable, slightly slightly<br />
stick), stick), and and slightly slightly plastic; plastic; very very few few to to few, few, fine fine to to medium medium roots; roots; gradual gradual<br />
and and smooth smooth transition transition to to<br />
Bws4 Bws4 yellowish yellowish brown brown (I0YR5/8); (I0YR5/8); gravelly gravelly clay; clay; many many (25%) (25%) fine fine to to medium, medium,<br />
distinct distinct diffuse diffuse 2.5YR4/8 2.5YR4/8 mottles; mottles; few few small small to to large, large, hard hard irregular irregular to to<br />
spherical spherical iron iron concretions; concretions; weak weak fine fine to to medium medium subangular subangular blocky; blocky;<br />
friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; very very few few very very fine fine to to fine fine roots. roots.<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bws3 Bws3<br />
Bws4 Bws4<br />
Horizoo Horizoo<br />
Ab Ab<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bws3 Bws3<br />
Bws4 Bws4<br />
Horizoo Horizoo<br />
Ab Ab<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bws3 Bws3<br />
Bws4 Bws4<br />
Pr<strong>of</strong>ile Pr<strong>of</strong>ile 201 201<br />
Particle Particle size size distribution distribution<br />
Depth Depth (cm) (cm) % % <strong>of</strong> <strong>of</strong> fine fine earth; earth; in in I'm I'm<br />
pH pH<br />
00<br />
PROFILE PROFILE 202<br />
Leg<strong>en</strong>d unit: Cu2<br />
Soil classification: classification: Acri-xanthic Acri-xanthic Ferralsol (FAO)<br />
Typic Kandiudult Kandiudult (Soil Taxonomy) Taxonomy)<br />
Description:<br />
Description:<br />
On 10-08-95 by Gerard Hazeu<br />
Location: Location:<br />
About 1.5 km km S <strong>of</strong> Engomba Engomba village; 3°04'84 Nand 10°39'45 E<br />
Elevation: Elevation:<br />
360 m m<br />
Landform and slope: Rolling uplands; lower slope 15 - 20%<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material: Gneisses <strong>of</strong> <strong>the</strong> Precambrian Precambrian shield<br />
Vegetation: Vegetation:<br />
Forest<br />
Drainage:<br />
Well drained<br />
Soil:<br />
Very deep, yellowish brown clay with sandy clay loam to to sandy clay<br />
topsoil<br />
Depth Depth (cm)<br />
0- 9<br />
9- 20<br />
20- 57<br />
57-160<br />
160-200<br />
On 10-08-95 by Gerard Hazeu<br />
Hor. Description Description<br />
Ah dark brown (lOYR3/3); (lOYR3/3); sandy clay loam; moderate moderate fine crumb to<br />
subangular subangular blocky; very friable, slightly sticky and slightly plastic;<br />
common fine to medium roots; clear and smooth transition to<br />
BA dark yellowish brown (lOYR4/4); (lOYR4/4); sandy clay loam; moderate fine<br />
subangular subangular blocky; blocky; friable, friable, slightly slightly sticky sticky and slightly slightly plastic; plastic; very few to to<br />
common, common, fine to medium roots; clear and wavy transition transition to<br />
Bwsl yellowish yellowish brown (lOYR5/6); (IOYR5/6); sandy clay; few (5%) medium medium faint to<br />
distinct, diffuse 5YR5/8 5YR5/8 mottles; weak to moderate, moderate, very fine to fine<br />
subangular subangular blocky; blocky; friable, friable, slightly slightly sticky sticky and slightly slightly plastic; plastic; patchy patchy thin<br />
clay and humus humus cutanS; cutanS; very few to common, common, fme to coarse roots; gradual gradual<br />
and wavy transition transition to<br />
Bws2 yellowish yellowish brown brown (lOYR5/8); (lOYR5/8); slightly slightly gravelly gravelly clay; few medium medium faint<br />
diffuse 5YR5/8 5YR5/8 mottles; very few « 5 %) %) small hard spherical iron<br />
concretions; concretions; weak very fine to fine subangular subangular blocky; friable, slightly<br />
sticky and slightly slightly plastic; plastic; patchy patchy thin clay and humus humus cutans; cutans; few to to<br />
common, very fine to fine roots; gradual and smooth transition transition to<br />
Bv yellowish yellowish brown (lOYR5/8); (IOYR5/8); gravelly gravelly clay; many (35%) medium medium faint<br />
diffuse 2.5YR4/8 2.5YR4/8 mottles; frequ<strong>en</strong>t small s<strong>of</strong>t irregular iron concretions;<br />
concretions;<br />
weak very fine to fine subangular subangular blocky; friable, slightly sticky and<br />
slightly plastic; very few to common, common, very fine to medium roots.<br />
Horizon Horizon<br />
Ah<br />
BA<br />
Bwsl Bwsl<br />
Bws2<br />
Bv<br />
Horizon Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2 Bws2<br />
Bv<br />
Horizon Horizon<br />
Ah<br />
BA<br />
Bwsl<br />
Bws2 Bws2<br />
Bv<br />
Pr<strong>of</strong>ile 202<br />
Particle Particle size distribution distribution<br />
Depth (cm) % % <strong>of</strong>fine earth; in J.lm<br />
pH<br />
PROFILE PROFILE 204 204<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: unit: Cu2 Cu2<br />
Soil Soil classification: classification: Acri-xanthic Acri-xanthic Ferralsol Ferralsol (FAO) (FAO)<br />
Typic Typic kandiudult kandiudult (Soil (Soil Taxonomy) Taxonomy)<br />
Description:<br />
Description:<br />
On On 10-08-95 10-08-95 by by Gerard Gerard Hazeu Hazeu<br />
Location: Location:<br />
About About I I km km S S <strong>of</strong> <strong>of</strong> Engomba Engomba village; village; 3°04'84 3°04'84 Nand Nand 10°39'45 10°39'45 E E<br />
Elevation: Elevation:<br />
390 390 m m<br />
Landform Landform and and slope: slope: Rolling Rolling uplands; uplands; upper upper slope slope 10- 10- 15% 15%<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material: Gneisses Gneisses <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Precambrian Precambrian shield shield<br />
Vegetation: Vegetation:<br />
Forest Forest<br />
Drainage: Drainage:<br />
Well Well drained drained<br />
Soil: Soil:<br />
Very Very deep, deep, yellowish yellowish brown brown clay clay with with sandy sandy clay clay loam loam to to sandy sandy clay clay<br />
topsoil topsoil<br />
Depth Depth (cm) (cm)<br />
0- 0- 6 6<br />
6- 6- 16 16<br />
16- 16- 47 47<br />
47-200 47-200<br />
1I0r. 1I0r. Descri Descri ption ption<br />
Ah Ah dark dark yellowish yellowish brown brown (IOYR3/4); (IOYR3/4); sandy sandy clay clay loam; loam; moderate moderate to to strong, strong,<br />
very very fine fine crumb crumb to to subangular subangular blocky; blocky; very very friable, friable, slightly slightly sticky sticky and and<br />
slightly slightly plastic; plastic; common common to to many, many, very very fine fine to to fine fine roots; roots; clear clear and and smooth smooth<br />
transition transition to to<br />
BA BA yellowish yellowish brown brown (lOYR5/6); (lOYR5/6); sandy sandy clay; clay; weak weak to to moderate, moderate, very very fine fine to to<br />
fine fine subangular subangular blocky; blocky; friable, friable, slightly slightly stick,), stick,), and and slightly slightly plastic; plastic; few few to to<br />
common, common, very very fine fine to to fine fine roots; roots; clear clear and and smooth smooth transition transition to to<br />
Bwsl Bwsl yellowish yellowish brown brown (lOYR5/8); (lOYR5/8); clay; clay; few few (5%) (5%) fine fine to to medium, medium, faint, faint, diffuse diffuse<br />
7.5YR6/8 7.5YR6/8 mottles; mottles; weak weak very very fine fine to to fine fine subangular subangular blocky; blocky; friable, friable,<br />
slightly slightly sticky sticky and and slightly slightly plastic; plastic; patchy patchy thin thin clay clay cutans; cutans; few few to to<br />
common, common, fine fine to to coarse coarse roots; roots; diffuse diffuse and and smooth smooth transition transition to to<br />
Bws2 Bws2 yellowish yellowish brown brown (lOYR5/8); (lOYR5/8); clay; clay; few few (10%) (10%) medium medium distinct distinct diffuse diffuse<br />
7.5YR6/8 7.5YR6/8 mottles; mottles; weak weak very very fine fine to to fine fine subangular subangular blocky; blocky; friable, friable,<br />
slightly slightly sticky sticky and and slightly slightly plastic; plastic; few few very very fine fine to to fine fine roots. roots.<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bws2 Bws2<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bws2 Bws2<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bws2 Bws2<br />
Pr<strong>of</strong>ile Pr<strong>of</strong>ile 204 204<br />
Particle Particle size size distribution distribution<br />
Depth Depth (cm) (cm) % % <strong>of</strong> <strong>of</strong> fine fine earth; earth; in in J.Im J.Im<br />
pH pH<br />
N N<br />
PROFILE PROFILE 216 216<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: unit:<br />
Soil Soil classification:<br />
classification:<br />
Description: Description:<br />
Location: Location:<br />
Elevation: Elevation:<br />
Landform Landform and and slope: slope:<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material:<br />
Vegetation: Vegetation:<br />
Drainage: Drainage:<br />
Soil: Soil:<br />
Depth Depth (cm) (cm) 1I0r. 1I0r.<br />
0- 0- 6 6 Ah Ah<br />
6- 6- 20 20 BA BA<br />
20- 20- 45 45 Bwsl Bwsl<br />
45-120 45-120 Bws2 Bws2<br />
120-200 120-200 BC BC<br />
Bh2 Bh2<br />
Acri-xanthic Acri-xanthic Ferralsol Ferralsol (FAO) (FAO)<br />
Typic Typic Kandiudult Kandiudult (Soil (Soil Taxonomy) Taxonomy)<br />
On On 12-08-95 12-08-95 by by Gerard Gerard Hazeu Hazeu<br />
About About I I km km S S <strong>of</strong> <strong>of</strong> Ma'am<strong>en</strong>yin Ma'am<strong>en</strong>yin village; village; 3°03'58 3°03'58 Nand Nand 10°46'42 10°46'42 E E<br />
450m 450m<br />
Complex Complex <strong>of</strong> <strong>of</strong> hills; hills; lower lower slope slope 25 25 -- 35% 35%<br />
Gneisses Gneisses <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Precambrian Precambrian shield shield<br />
Forest Forest<br />
Well Well drained drained<br />
Very Very deep, deep, yellowish yellowish brown brown clay clay with with sandy sandy clay clay loam loam to to sandy sandy clay clay<br />
topsoil topsoil<br />
Description Description<br />
very very dark dark brown brown (7.5YR2.5/3); (7.5YR2.5/3); sandy sandy clay clay loam loam to to sandy sandy clay; clay; moderate moderate<br />
very very fine fine to to fine fine crumb crumb to to subangular subangular blocky; blocky; friable, friable, slightly slightly sticky sticky and and<br />
slightly slightly plastic; plastic; few few to to many, many, fine fine to to coarse coarse roots; roots; clear clear and and smooth smooth<br />
transition transition to to<br />
dark dark yellowish yellowish brown brown (IOYR4/6); (IOYR4/6); sandy sandy clay; clay; moderate moderate very very fine fine to to fine fine<br />
subangular subangular blocky; blocky; friable, friable, slightly slightly stick), stick), and and slightly slightly plastic; plastic; few few to to many, many,<br />
fine fine to to medium medium roots; roots; gradual gradual and and smooth smooth transition transition to to<br />
yellowish yellowish brown brown (I (I OYR5/6); OYR5/6); clay; clay; weak weak to to moderate, moderate, very very fine fine subangular subangular<br />
block)'; block)'; friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; very very few few to to many, many, fine fine<br />
to to coarse coarse roots; roots; clear clear and and smooth smooth transition transition to to<br />
yellowish yellowish brown brown (IOYR5/8); (IOYR5/8); clay; clay; very very few few (2%) (2%) fine fine faint faint diffuse diffuse 5YR5/8 5YR5/8<br />
mottles; mottles; weak weak to to moderate, moderate, very very fine fine subangular subangular blocky; blocky; friable, friable, slightly slightly<br />
sticky sticky and and slightly slightly plastic; plastic; few few to to common, common, very very fine fine to to fine fine roots; roots; clear clear<br />
and and wavy wavy transition transition to to<br />
yellowish yellowish brown brown (IOYR5/8); (IOYR5/8); gravelly, gravelly, slightly slightly stony stony clay; clay; many many (15%) (15%) fine fine<br />
faint faint diffuse diffuse 5YR5/8 5YR5/8 mottles; mottles; few few small small to to large, large, hard hard irregular irregular to to angular angular<br />
iron iron concretions; concretions; weak weak very very fine fine subangular subangular blocky; blocky; friable, friable, slightly slightly sticky sticky<br />
and and slightly slightly plastic; plastic; very very few few very very fine fine to to fine fine roots. roots.<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
BC BC<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
BC BC<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
BC BC<br />
Pr<strong>of</strong>ile Pr<strong>of</strong>ile 216 216<br />
Particle Particle size size distribution distribution<br />
Depth Depth % % <strong>of</strong> <strong>of</strong> fine fine earth; earth; in in J.lnI J.lnI<br />
(cm) (cm)<br />
pH pH<br />
PROFILE PROFILE 137 137<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: unit:<br />
Soil Soil classification:<br />
classification:<br />
Description:<br />
Description:<br />
Location: Location:<br />
Elevation: Elevation:<br />
Landform Landform and and slope: slope:<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material:<br />
Vegetation: Vegetation:<br />
Drainage: Drainage:<br />
Soil: Soil:<br />
Depth Depth (cm) (cm) Hor. Hor.<br />
0- 0- 6 6 Ah Ah<br />
6- 6- 22 22 BA BA<br />
IV IV 22- 22- 74 74 Bwsl Bwsl<br />
VI VI<br />
74-127 74-127 Bws2 Bws2<br />
127-170 127-170 Bvl Bvl<br />
170-200 170-200 Bv2 Bv2<br />
DuI DuI<br />
Ferrali Ferrali ferric ferric Acrisol Acrisol (FAO) (FAO)<br />
Typic Typic Kandiudult Kandiudult (Soil (Soil Taxonomy) Taxonomy)<br />
On On 26-06-95 26-06-95 by by Gerard Gerard Hazeu Hazeu<br />
About About 2 2 km km NW NW <strong>of</strong>Toko <strong>of</strong>Toko village; village; 2°57'28 2°57'28 Nand Nand 10°29'02 10°29'02 E E<br />
<strong>II</strong>0m <strong>II</strong>0m<br />
Undulating Undulating to to rolling rolling uplands; uplands; middle middle slope slope 5 5 -- 10% 10%<br />
Gneisses Gneisses <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Precambrian Precambrian shield shield<br />
Forest Forest<br />
Moderately Moderately well well drained drained<br />
Vel)' Vel)' deep, deep, yellowish yellowish brown brown sandy sandy clay clay to to clay clay with with loamy loamy sand sand to to sandy sandy loam loam topsoil topsoil<br />
Description<br />
Description<br />
dark dark yellowish yellowish brown brown (I (I OYR4/4); OYR4/4); loamy loamy sand sand to to sandy sandy loam; loam; weak weak vel)' vel)' fine fine granular granular<br />
and and weakly weakly coher<strong>en</strong>t coher<strong>en</strong>t slructure; slructure; loose loose 10 10 vel)' vel)' friable, friable, non non slicky slicky and and slighlly slighlly plastic; plastic;<br />
common, common, vel)' vel)' fine fine 10 10 fine fine roots; roots; clear clear and and smooth smooth Iransition Iransition to to<br />
yellowish yellowish brown brown (IOYR5/6); (IOYR5/6); sandy sandy clay clay loam; loam; weak weak to to moderate, moderate, vel)' vel)' fine fine 10 10 fine fine<br />
subangular subangular bloc).:y; bloc).:y; friable, friable, slighlly slighlly slicky slicky and and slighlly slighlly plastic; plastic; few few 10 10 common, common, fine fine to to<br />
coarse coarse rools; rools; gradual gradual and and smoolh smoolh Iransilion Iransilion 10 10<br />
yellowish yellowish brown brown (IOYR518); (IOYR518); sandy sandy clay clay loam; loam; few few (10%) (10%) fine fine faint faint diffuse diffuse 7.5YR518 7.5YR518<br />
mOllles; mOllles; weak weak to to moderate, moderate, vel)' vel)' fine fine to to fine fine subangular subangular blocky; blocky; friable, friable, slighlly slighlly sticky sticky<br />
and and slightly slightly plastic; plastic; few few to to many, many, fine fine to to medium medium roots; roots; gradual gradual and and smooth smooth transition transition<br />
to to<br />
yellowish yellowish brown brown (IOYR5/8); (IOYR5/8); vel)' vel)' gravelly, gravelly, stony stony sandy sandy clay clay loam; loam; few few (15%) (15%) fine fine faint faint<br />
diffuse diffuse 7.5YR5/8 7.5YR5/8 monIes; monIes; few few to to frequ<strong>en</strong>l, frequ<strong>en</strong>l, small small to to large, large, s<strong>of</strong>t s<strong>of</strong>t 10 10 hard, hard, irregular irregular to to<br />
spherical spherical iron iron concretions; concretions; weak weak to to moderate, moderate, vel)' vel)' fine fine to to fine fine subangular subangular blocky; blocky;<br />
friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; few, few, vel)' vel)' fine fine to to fine fine roots; roots; gradual gradual and and<br />
smooth smooth transition transition to to<br />
yellowish yellowish brown brown (I (I OYR518); OYR518); slightly slightly gravelly gravelly clay clay loam; loam; many many (20%) (20%) medium medium<br />
promin<strong>en</strong>l promin<strong>en</strong>l clear clear 5YR5/8 5YR5/8 monIes; monIes; vel)' vel)' few few 10 10 few, few, small small s<strong>of</strong>t s<strong>of</strong>t to to hard, hard, spherical spherical iron iron<br />
concretions; concretions; weak weak fine fine subangular subangular blocky; blocky; friable, friable, slightly slightly slicky slicky and and slightly slightly plastic; plastic;<br />
vel)' vel)' few few vel)' vel)' fine fine 10 10 fine fine roots; roots; gradual gradual and and smooth smooth transition transition to to<br />
yellowish yellowish brown brown (IOYRS/8); (IOYRS/8); gravelly gravelly clay clay loam; loam; many many (35%) (35%) medium medium promin<strong>en</strong>t promin<strong>en</strong>t clear clear<br />
2.5YR4/8 2.5YR4/8 monIes; monIes; vel)' vel)' few few to to frequ<strong>en</strong>t, frequ<strong>en</strong>t, small small s<strong>of</strong>t s<strong>of</strong>t to to hard, hard, irregular irregular to to spherical spherical iron iron<br />
concretions; concretions; weak weak fine fine subangular subangular blocky; blocky; friable, friable, slightly slightly sticky sticky and and slighlly slighlly plastic; plastic;<br />
no no roots. roots.<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bvl Bvl<br />
Bv2 Bv2<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bvl Bvl<br />
Bv2 Bv2<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bvl Bvl<br />
Bv2 Bv2<br />
Pr<strong>of</strong>ile Pr<strong>of</strong>ile 137 137<br />
Particle Particle size size distribulion distribulion<br />
Deplh Deplh (cm) (cm) % % <strong>of</strong> <strong>of</strong> fine fine earth; earth; in in !lm !lm<br />
pH pH<br />
t-.J<br />
0\<br />
PROFILE 139<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: unit: DuI<br />
Soil classification: Acri-xanthic Ferralsol (FAO)<br />
Typic Kandiudult (Soil Taxonomy)<br />
Description:<br />
On 26-06-95 by Gerard Hazeu<br />
Location:<br />
About About I I km km NW NW <strong>of</strong>Toko <strong>of</strong>Toko village; village; Z056'59 Z056'59 Nand Nand 10°29'84 10°29'84 E E<br />
Elevation:<br />
140m<br />
Landform and slope: Undulating to rolling uplands; lower slope 10%<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material: Gneisses Gneisses <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Precambrian Precambrian shield shield<br />
Vegetation:<br />
Forest Forest<br />
Drainage: Drainage:<br />
Moderately Moderately well well to to well well drained drained<br />
Soil:<br />
Very deep, deep, yellowish yellowish brown brown sandy sandy clay clay to to clay clay with with loamy loamy sand sand to to sandy sandy<br />
loam topsoil<br />
Depth Depth (cm) (cm)<br />
0- 0- 7<br />
7- 7- 17 17<br />
17- 42<br />
42- 82<br />
82-157 82-157<br />
157-205 157-205<br />
1I0r. 1I0r.<br />
Description<br />
Ah Ah dark brown brown (lOYR3/3); (lOYR3/3); sandy loam; loam; moderate moderate very fine fine to to fine fine crumb crumb to to<br />
subangular subangular blocky; blocky; very very friable, friable, non non sticky, sticky, slightly slightly plastic plastic and and weakly weakly<br />
smeary; smeary; common common to to many, many, very very fine fine to to fine roots; roots; clear and and smooth smooth<br />
transition transition to to<br />
BA BA dark dark yellowish yellowish brown brown (IOYR4/6); (lOYR4/6); sandy sandy clay clay loam; loam; weak weak to to moderate, moderate, very very<br />
fine fine to fine subangular subangular blocky; friable, friable, slightly slightly sticky and and slightly slightly plastic; plastic;<br />
very very few, fine to medium medium roots; roots; clear clear and smooth transition to<br />
Bwsl Bwsl yellowish brown (IOYR5/6); sandy clay loam; moderate very fine to fine<br />
sub sub angular block],; block]'; friable, slightly sticky and slightly plastic; very few to<br />
few, few, very fine fine to to fine fine roots; gradual gradual and and smooth smooth transition transition to to<br />
Bws2 yellowish brown (lOYR5/8); sandy sandy clay; clay; few (2-5%) (2-5%) fine faint diffuse<br />
7.5YR5/8 monies; weak to moderate, very fine to fine subangular blocky;<br />
friable, slightly sticky and slightly plastic; few very fine to fine roots;<br />
gradual gradual and and smooth smooth transition transition to to<br />
Bws3 yellowish brown (IOYR5/8); sandy clay to clay; clay; few (10%) fine faint<br />
diffuse 5YR5/8 monies; weak to moderate, very fine to fine subangular<br />
block]'; block],; friable, friable, slightly slightly stick], stick], and and slightly slightly plastic; plastic; very very few few very very fine fine roots; roots;<br />
gradual gradual and and smooth smooth transition transition to to<br />
Bv Bv yellowish yellowish brown brown (lOYR5/8); (lOYR5/8); slightly slightly gravelly gravelly sandy sandy clay clay to to clay; clay; many many<br />
(25%) (25%) medium medium distinct distinct clear clear 2.5YR4/8 monies; monies; very very few few to to few, few, small small s<strong>of</strong>t s<strong>of</strong>t<br />
to hard, hard, spherical spherical to to irregular irregular iron iron concretions; concretions; weak weak fine fine subangular subangular<br />
blocky; friable, friable, slightly slightly sticky and slightly plastic; plastic; no roots.<br />
Horizon Horizon Depth (cm)<br />
Pr<strong>of</strong>ile 139<br />
Particle size distribution<br />
% % <strong>of</strong> <strong>of</strong> fine fine earth; earth; in in J.lm J.lm<br />
pH<br />
PROFILE PROFILE ISO ISO<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: unit: Dpd Dpd<br />
Soil Soil classification: classification: Acri-plinthic Acri-plinthic Ferralsol Ferralsol (FAO) (FAO)<br />
Plinthudult Plinthudult (Soil (Soil Taxonomy) Taxonomy)<br />
Description:<br />
Description:<br />
On On 11-07-95 11-07-95 by by Gerard Gerard Ilazeu Ilazeu<br />
Location: Location:<br />
About About 300 300 m m NE NE <strong>of</strong> <strong>of</strong> Mel<strong>en</strong> Mel<strong>en</strong> village; village; 3 3 °02'80 °02'80 Nand Nand 10°31'64 10°31'64 E E<br />
Elevation: Elevation:<br />
Landfarm Landfarm and and slupe: slupe: Undulating Undulating dissech:d dissech:d erosional erosional plain; plain; lower lower slope slope 0 0 -- 5% 5%<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material: Gneisses Gneisses and/or and/or migmatites migmatites <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Precambrian Precambrian shield shield<br />
Vegetation: Vegetation:<br />
Cacao Cacao plantation plantation<br />
Drainage: Drainage:<br />
Moderately Moderately well well drained drained<br />
Soil: Soil:<br />
Deep, Deep, yellowish yellowish brown brown sandy sandy clay clay to to clay clay with with loamy loamy sand sand to to sandy sandy loam loam<br />
topsoil topsoil<br />
Depth Depth (cm) (cm)<br />
0- 0- 6 6<br />
6- 6- 17 17<br />
17- 17- 48 48<br />
48- 48- 78 78<br />
78-160 78-160<br />
Hor. Hor.<br />
120m 120m<br />
Description Description<br />
Ah Ah dark dark greyish greyish brown brown (lOYR4/1); (lOYR4/1); loamy loamy sand; sand; weakly weakly coher<strong>en</strong>t coher<strong>en</strong>t single single grain; grain;<br />
loose, loose, loose, loose, non non sticky sticky and and non non plastic; plastic; very very few few to to few, few, fine fine to to medium medium<br />
roots; roots; abrupt abrupt and and smooth smooth transition transition to to<br />
BA BA very very pale pale brown brown (IOYR8/3); (IOYR8/3); slightly slightly gravelly gravelly loamy loamy sand sand to to sandy sandy loam; loam;<br />
moderately moderately coher<strong>en</strong>t coher<strong>en</strong>t single single grain grain and and porous porous massive; massive; loose, loose, loose, loose, non non<br />
sticky sticky and and non non plastic; plastic; few few very very fine fine to to fine fine roots; roots; clear clear and and smooth smooth<br />
transition transition to to<br />
Bws Bws yellow yellow (lOYR7/8); (lOYR7/8); very very gravelly gravelly sandy sandy clay; clay; many many (20%) (20%) fine fine faint faint diffuse diffuse<br />
5YR5/8 5YR5/8 mottles; mottles; few few small small hard hard spherical spherical iron iron concretions; concretions; weak weak fine fine<br />
subangular subangular blocky blocky and and strongly strongly coher<strong>en</strong>t coher<strong>en</strong>t porous porous massive; massive; friable, friable, slightly slightly<br />
sticky sticky and and slightly slightly plastic; plastic; very very few few very very fine fine to to fine fine roots; roots; gradual gradual and and<br />
smooth smooth transition transition to to<br />
Bv Bv I I yellow yellow (I (I OYR OYR 7/6); 7/6); very very gravelly gravelly clay; clay; many many (20%) (20%) medium medium distinct distinct diffuse diffuse<br />
2.5YR4/8 2.5YR4/8 mottles; mottles; very very few few to to frequ<strong>en</strong>t, frequ<strong>en</strong>t, small small to to large, large, s<strong>of</strong>t s<strong>of</strong>t to to hard, hard,<br />
irregular irregular to to spherical spherical iron iron concretions; concretions; weak weak very very fine fine to to fine fine subangular subangular<br />
blocky; blocky; friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; very very few few fine fine roots; roots;<br />
diffuse diffuse and and smooth smooth transition transition to to<br />
Bv2 Bv2 light light yellowish yellowish brown brown (IOYR6/4); (IOYR6/4); gravelly gravelly clay; clay; many many (20%) (20%) medium medium<br />
promin<strong>en</strong>t promin<strong>en</strong>t diffuse diffuse 2.5YR4/8 2.5YR4/8 mottles; mottles; few few to to frequ<strong>en</strong>t, frequ<strong>en</strong>t, small small to to large, large, s<strong>of</strong>t s<strong>of</strong>t<br />
to to hard, hard, irregular irregular to to spherical spherical iron iron concretions; concretions; weak weak very very fine fine to to fine fine<br />
subangular subangular blocky; blocky; friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; very very few few<br />
fine fine roots. roots.<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bws Bws<br />
Bvl Bvl<br />
Bv2 Bv2<br />
Bv2 Bv2<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bws Bws<br />
Bvl Bvl<br />
Bv2 Bv2<br />
Bv2 Bv2<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bws Bws<br />
Bvl Bvl<br />
Bv2 Bv2<br />
Bv2 Bv2<br />
Pr<strong>of</strong>ile Pr<strong>of</strong>ile 150 150<br />
Particle Particle size size distribution distribution<br />
Depth Depth (cm) (cm) % % <strong>of</strong> <strong>of</strong> fine fine earth; earth; inllm inllm<br />
pH pH<br />
10<br />
00<br />
PROFILE PROFILE ISI ISI<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: Dpd<br />
Soil classification: classification: Ferrali Ferrali haplic haplic Acrisol Acrisol (FAO) (FAO)<br />
Typic Kandiudult Kandiudult (Soil Taxonomy) Taxonomy)<br />
Description:<br />
Description:<br />
On 11-07-95 11-07-95 by Gerard Gerard Hazeu Hazeu<br />
Location: Location:<br />
About 200 m SW <strong>of</strong> Mel<strong>en</strong> village; 3 °02'80 Nand 10°31 '64 E<br />
Elevation: Elevation:<br />
Landform and slope: Undulating Undulating dissected erosional plain; lower slope 0 - 5%<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material: Gneisses Gneisses and/or and/or migmatites migmatites <strong>of</strong> <strong>the</strong> Precambrian Precambrian shield shield<br />
Vegetation: Vegetation:<br />
Secondary Secondary forest lorest<br />
Drainage: Drainage:<br />
Well drained<br />
Soil:<br />
Deep, yellowish yellowish brown sandy clay loam with loamy sand to sand topsoil<br />
Depth (cm)<br />
0- 7<br />
7- 15<br />
15- 38<br />
38- 80<br />
80-\20 80-\20<br />
120m<br />
1I0r. Description Description<br />
Ah dark greyish greyish brown (IOYR4/1); (IOYR4/I); loamy sand; weakly weakly coher<strong>en</strong>t coher<strong>en</strong>t single grain;<br />
loose, loose, non sticky and non plastic; plastic; many very fine to fine roots; roots; clear<br />
and smooth smooth transition transition to<br />
AB brown (IOYR5/3); (IOYR5/3); sand; moderately moderately coher<strong>en</strong>t porous massive; loose, non<br />
sticky and slightly plastic; few to common, fine fine to to medium roots; clear and<br />
smooth smooth transition transition to<br />
BA pale yellow (2.5Y7/4); (2.5Y7/4); 10anlY sand; weak very fine subangular subangular blocky and<br />
moderately moderately coher<strong>en</strong>t coher<strong>en</strong>t porous massive; massive; very friable, non sticky and non<br />
plastic; plastic; few to common, common, fine to medium medium roots; roots; gradual gradual and smooth smooth<br />
transition transition to<br />
Bwsl brownish yellow (lOYR6/6); (iOYR6/6); slightly gravelly sandy clay loam; few (2%)<br />
fine faint diffuse 5YR5/8 mottles; weak very fine to fine subangular subangular<br />
blocky; very friable, slightly sticky and slightly plastic; few very fine to<br />
fine roots; clear and wavy transition transition to<br />
Bws2 brownish brownish yellow (I0YR6/6); (IOYR6/6); very gravelly, gravelly, stony sandy sandy clay loam; few<br />
(5%) fine faint diffuse 5YR5/8 mottles; few small to large, hard irregular<br />
iron concretions; concretions; weak fine subangular subangular blocky; friable, slightly sticky and<br />
slightly plastic; few very fine to fine roots.<br />
Horizon<br />
Ah<br />
AB<br />
BA<br />
Bwsl<br />
Bws2<br />
Horizon Horizon<br />
Ah<br />
AB<br />
BA<br />
Bwsl<br />
Bws2<br />
Horizon<br />
Ah<br />
AB<br />
BA<br />
Bwsl<br />
Bws2 Bws2<br />
Bwsl<br />
Pr<strong>of</strong>ile 151 151<br />
Particle Particle size distribution distribution<br />
Depth (cm) % <strong>of</strong>fine earth; in ).101 J.Im<br />
pH<br />
PROFILE PROFILE 217 217<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: unit: Du2 Du2<br />
Soil Soil classification: classification: lIaplic lIaplic Acrisol Acrisol (FAO) (FAO)<br />
Typic Typic Paleudult Paleudult (Soil (Soil Taxonomy) Taxonomy)<br />
Description:<br />
Description:<br />
On On 14-08-95 14-08-95 by by Gerard Gerard Hazeu Hazeu<br />
Location: Location:<br />
Elevation: Elevation:<br />
Landform Landform and and slope: slope: Rolling Rolling uplands; uplands; lower lower slope slope 20% 20%<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material: Gneisses Gneisses and/or and/or migmatites migmatites <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Precambrian Precambrian shield shield<br />
Vegetation: Vegetation:<br />
Forest Forest<br />
Drainage: Drainage:<br />
Moderately Moderately well well drained drained<br />
Soil: Soil:<br />
Very Very deep, deep, yellowish yellowish brown brown sandy sandy clay clay to to clay clay with with sandy sandy loam loam to to loamy loamy<br />
sand sand topsoil topsoil<br />
Depth Depth (cm) (cm)<br />
0- 0- 4 4<br />
4- 4- 16 16<br />
16- 16- 36 36<br />
36-100 36-100<br />
100-160 100-160<br />
Hor. Hor.<br />
About2.S About2.S km km SW SW <strong>of</strong>Mel<strong>en</strong> <strong>of</strong>Mel<strong>en</strong> village; village; 3°02'80 3°02'80 Nand Nand 10°31'64 10°31'64 E E<br />
170m 170m<br />
Description Description<br />
Ah Ah very very dark dark brown brown (lOYR2/2); (lOYR2/2); sandy sandy loam; loam; weak weak very very fine fine crumb crumb and and<br />
weakly weakly coher<strong>en</strong>t coher<strong>en</strong>t single single grain; grain; loose, loose, non non sticky sticky and and slightly slightly plastic; plastic;<br />
common common to to many, many, fine fine to to medium medium roots; roots; clear clear and and smooth smooth transition transition to to<br />
AE AE yellowish yellowish brown brown (lOYRS/4); (lOYRS/4); loamy loamy sand; sand; weak weak very very fine fine subangular subangular<br />
blocky blocky and and weakly weakly coher<strong>en</strong>t coher<strong>en</strong>t single single grain; grain; very very friable, friable, non non sticky sticky and and non non<br />
plastic; plastic; few few to to common, common, very very fine fine to to fine fine roots; roots; gradual gradual and and smooth smooth<br />
transition transition to to<br />
Bwsl Bwsl yellowish yellowish brown brown (IOYRS/6); (IOYRS/6); sandy sandy loam; loam; few few (5 (5 -10%) -10%) fine fine distinct distinct diffuse diffuse<br />
7.5YR5/8 7.5YR5/8 moUles; moUles; weak weak fine fine subangular subangular blocky blocky and and weakly weakly coher<strong>en</strong>t coher<strong>en</strong>t<br />
single single grain; grain; very very friable, friable, non non sticky sticky and and slightly slightly plastic; plastic; few few very very fine fine to to<br />
fine fine roots; roots; gradual gradual and and wavy wavy transition transition to to<br />
Bws2 Bws2 yellowish yellowish brown brown (lOYRS/8); (lOYRS/8); gravelly gravelly sandy sandy clay clay loam; loam; few few (10%) (10%) fine fine to to<br />
medium, medium, distinct distinct diffuse diffuse 7.SYR5/8 7.SYR5/8 mottles; mottles; few few small small hard hard spherical spherical iron iron<br />
concretions; concretions; weak weak to to moderate, moderate, very very fine fine to to fine fine angular angular to to subangular subangular<br />
blocky; blocky; friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; very very few few very very fine fine to to<br />
fine fine roots; roots; gradual gradual and and wavy wavy transition transition to to<br />
Bv Bv yellowish yellowish brown brown (lOYR5/8); (lOYR5/8); gravelly gravelly clay; clay; many many (30%) (30%) medium medium distinct distinct<br />
to to promin<strong>en</strong>t, promin<strong>en</strong>t, clear clear IOYR7/8 IOYR7/8 moUles; moUles; few few to to frequ<strong>en</strong>t, frequ<strong>en</strong>t, small small s<strong>of</strong>t s<strong>of</strong>t to to hard, hard,<br />
irregular irregular to to spherical spherical iron iron concretions; concretions; weak weak to to moderate, moderate, very very fine fine to to fine fine<br />
subangular subangular blocky; blocky; friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; very very few few<br />
very very fine fine to to fine fine roots. roots.<br />
Horizon Horizon<br />
Ah Ah<br />
AE AE<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bv Bv<br />
Horizon Horizon<br />
Ah Ah<br />
AE AE<br />
Bwsl Bwsl<br />
Bws2 Bws2<br />
Bv Bv<br />
Horizon Horizon<br />
Ah Ah<br />
AE AE<br />
BwsI BwsI<br />
Bws2 Bws2<br />
Bv Bv<br />
Pr<strong>of</strong>ile Pr<strong>of</strong>ile 217 217<br />
Particle Particle size size distribution distribution<br />
Depth Depth (cm) (cm) % % <strong>of</strong> <strong>of</strong> fine fine earth; earth; in in Ilm Ilm<br />
pH pH<br />
PROFILE 218<br />
Leg<strong>en</strong>d unit:<br />
Soil Soil classification:<br />
classification:<br />
Description: Description:<br />
Location: Location:<br />
Elevation: Elevation:<br />
Landform Landform and slope:<br />
Par<strong>en</strong>t material:<br />
Vegetation: Vegetation:<br />
Drainage: Drainage:<br />
Soil:<br />
Depth Depth (cm) (cm) 1I0r. 1I0r.<br />
0-3 Ah Ah<br />
w<br />
0 3-16125 AE AE<br />
16125-S0 16125-S0 Bwsl Bwsl<br />
80-lIS 80-11S Bv<br />
118-130 118-130 BC BC<br />
Du2 Du2<br />
Ferralic plinthic Acrisol (FAO)<br />
Plinthudult Plinthudult (Soil (Soil Taxonomy) Taxonomy)<br />
On 14-08-95 by Gerard Hazeu<br />
About About 2.5 km SW SW <strong>of</strong> Mel<strong>en</strong> Mel<strong>en</strong> village; village; 3 3 °02'80 °02'80 Nand Nand 10°31 10°31 '64 '64 E E<br />
220 220 m m<br />
Rolling uplands; upper slope 15%<br />
Gneisses Gneisses and/or and/or migmatites migmatites <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Precambrian Precambrian shield shield<br />
Forest Forest<br />
Moderately Moderately well drained<br />
Deep, yellowish brown, sandy clay to clay with sandy loam to loamy sand<br />
topsoil topsoil<br />
Description<br />
very very dark dark greyish greyish brown brown (IOYR3/2); (IOYR3/2); 10anlY 10anlY sand; sand; weak weak very very fine fine crumb crumb<br />
and weakly coher<strong>en</strong>t single grain; loose, non sticky and non plastic;<br />
common common to to many, many, very very fine fine to to fine fine roots; roots; clear clear and and smooth smooth transition transition to to<br />
yellowish brown (IOYR5/4); sandy loam; weak very fine subangular<br />
block-y and moderately coher<strong>en</strong>t single grain; very friable, non sticky and<br />
slightly slightly plastic; few to common, fine to medium roots; gradual and wavy<br />
transition to<br />
brownish brownish yellow (IOYR6/S); gravelly sandy clay loam; many (15 - 25%)<br />
medium medium faint faint to to distinct, distinct, diffuse diffuse 7.5YR5/S 7.5YR5/S mottles; mottles; few few small small hard hard<br />
spherical spherical iron iron concretions; concretions; weak weak to moderate, moderate, very very fine fine to to fine fine subangular subangular<br />
blocky; blocky; friable, slightly slightly sticky and slightly plastic; very few to common,<br />
fine fine to to medium medium roots; roots; gradual gradual and and smooth smooth transition transition to to<br />
light light yellowish yellowish brown brown (IOYR6/4); (IOYR6/4); very very gravelly gravelly sandy sandy clay; clay; many many (25 (25 --<br />
40%) 40%) medium medium distinct distinct diffuse diffuse 7.5YR6/8 7.5YR6/8 mottles; mottles; frequ<strong>en</strong>t frequ<strong>en</strong>t small small hard hard<br />
spherical spherical iron iron concretions; concretions; weak weak to moderate, moderate, very very fine fine to fine fine subangular subangular<br />
blocky; friable, slightly slightly sticky and slightly plastic; very few very fine to<br />
fine roots; gradual and smooth transition to<br />
light light yellowish yellowish brown brown (IOYR6/4); (IOYR6/4); very very gravelly gravelly sandy sandy clay; clay; many many (25 (25 --<br />
40%) 40%) medium medium distinct distinct diffuse diffuse 7.5YR6/8 7.5YR6/8 mottles; mottles; few few small small to to large, large, s<strong>of</strong>t s<strong>of</strong>t<br />
irregular irregular to to angular angular iron iron concretions; concretions; weak weak very very fine fine subangular subangular blocky blocky and and<br />
moderately coher<strong>en</strong>t massive; friable, slightly sticky sticky and slightly slightly plastic;<br />
no no roots. roots.<br />
Horizon Horizon Depth Depth (cm) (cm)<br />
Pr<strong>of</strong>ile 218<br />
Particle size distribution distribution<br />
% % <strong>of</strong> <strong>of</strong> fine fine earth; earth; in in flm flm<br />
pH pH<br />
w w<br />
PROFILE PROFILE 219 219<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: unit:<br />
Soil Soil classification:<br />
classification:<br />
Description: Description:<br />
Location: Location:<br />
Elevation: Elevation:<br />
Landfonn Landfonn and and slope: slope:<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material:<br />
Vegetation: Vegetation:<br />
Drainage: Drainage:<br />
Soil: Soil:<br />
Depth Depth (cm) (cm) Hor. Hor.<br />
0- 0- 3 3 Ah Ah<br />
3 3 -- 14 14 BA BA<br />
14-79 14-79 Bws Bws<br />
Du2 Du2<br />
Acri-xanthic Acri-xanthic Ferralsol Ferralsol (FAO) (FAO)<br />
Typic Typic Kandiudult Kandiudult (Soil (Soil Taxonomy) Taxonomy)<br />
On On 14-08-95 14-08-95 by by Gerard Gerard Hazeu Hazeu<br />
About About 2.5 2.5 km km SW SW <strong>of</strong>Mel<strong>en</strong> <strong>of</strong>Mel<strong>en</strong> village; village; 3 3 °02'80 °02'80 Nand Nand 10°31 10°31 '64 '64 E E<br />
220 220 m m<br />
Rolling Rolling uplands; uplands; upper upper slope slope 15% 15%<br />
Gm:isses Gm:isses and/or and/or migmatites migmatites <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Precambrian Precambrian shield shield<br />
Forest Forest<br />
Well Well drained drained<br />
Moderately Moderately deep, deep, yellowish yellowish brown brown sandy sandy clay clay to to clay clay with with sandy sandy loam loam to to<br />
loamy loamy sand sand topsoil topsoil<br />
Description Description<br />
dark dark brown brown (lOYR3/3); (lOYR3/3); sandy sandy loam; loam; weak weak very very fine fine crumb crumb to to subangular subangular<br />
blocky; blocky; very very friable, friable, slightly slightly stick), stick), and and slightly slightly plastic; plastic; common common to to many, many,<br />
very very fine fine to to fine fine roots; roots; clear clear and and smooth smooth transition transition<br />
dark dark yellowish yellowish brown brown (IOYR4/6); (IOYR4/6); sandy sandy clay clay loam; loam; weak weak very very fine fine to to fine fine<br />
subangular subangular blocky; blocky; very very friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; few few to to<br />
many, many, fine fine to to medium medium roots; roots; gradual gradual and and smooth smooth transition transition to to<br />
yellowish yellowish brown brown (lOYR5/8); (lOYR5/8); clay; clay; moderate moderate fine fine subangular subangular blocky; blocky;<br />
friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; few few to to common, common, very very fine fine to to<br />
fine fine roots. roots.<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bws Bws<br />
CB CB<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bws Bws<br />
CB CB<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bws Bws<br />
CB CB<br />
Pr<strong>of</strong>ile Pr<strong>of</strong>ile 219 219<br />
Particle Particle size size distribution distribution<br />
Depth Depth (cm) (cm) % % <strong>of</strong> <strong>of</strong> fine fine earth; earth; in in j.lm j.lm<br />
pH pH<br />
PROFILE PROFILE 138 138<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: unit:<br />
Soil Soil classification:<br />
classification:<br />
Description:<br />
Description:<br />
Location: Location:<br />
Elevation: Elevation:<br />
Landforrn Landforrn and and slope: slope:<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material:<br />
Vegetation: Vegetation:<br />
Drainage: Drainage:<br />
Soil: Soil:<br />
Depth Depth (cm) (cm) Hor. Hor.<br />
0- 0- 5 5 Ah Ah<br />
w w<br />
w 5- 5- 12 12 BA BA<br />
12- 12- 75 75 Bws Bws<br />
75-100 75-100 Bo/r Bo/r<br />
100-135 100-135 Cr Cr<br />
E E in in Dui Dui<br />
Ferrali-gleyic Ferrali-gleyic Cambisol Cambisol (FAO) (FAO)<br />
Oxyaquic Oxyaquic Dystropept Dystropept (Soil (Soil Taxonomy) Taxonomy)<br />
On On 26-06-95 26-06-95 by by Gerard Gerard Hazeu Hazeu<br />
About About 2 2 km km NW NW <strong>of</strong>Toko <strong>of</strong>Toko village; village; 2° 2° 57'28 57'28 Nand Nand 10°29'02 10°29'02 E E<br />
lOOm lOOm<br />
Undulating Undulating to to rolling rolling uplands; uplands; valley valley bottom bottom<br />
Alluvial Alluvial deposists deposists derived derived from from gneisses gneisses <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Precambrian Precambrian shield shield<br />
Forest Forest<br />
Poorly Poorly to to imperfectly imperfectly drained drained<br />
Moderately Moderately deep, deep, yellow yellow loamy loamy sand sand to to sandy sandy loam loam with with humic humic topsoil topsoil<br />
Description Description<br />
very very dark dark brown brown (IOYR2/2); (IOYR2/2); loamy loamy sand; sand; weakly weakly coher<strong>en</strong>t coher<strong>en</strong>t structure structure and and<br />
weak weak very very fine fine to to fine fine crumb crumb to to subangular subangular blocky; blocky; loose, loose, non non sticky, sticky,<br />
slightly slightly plastic; plastic; many, many, very very fine fine to to fine fine roots; roots; clear clear and and smooth smooth transition transition<br />
to to<br />
yellowish yellowish brown brown (IOYR5/4); (IOYR5/4); loamy loamy sand; sand; weak weak very very fine fine to to fine fine subangular subangular<br />
blocky; blocky; non non sticky sticky and and slightly slightly plastic; plastic; few few to to many, many, fine fine to to medium medium roots; roots;<br />
gradual gradual and and smooth smooth transition transition to to<br />
yellow yellow (IOYR7/8); (IOYR7/8); sandy sandy loam; loam; weak weak very very fine fine to to fine fine subangular subangular blocky; blocky;<br />
slightly slightly sticky sticky and and slightly slightly plastic; plastic; very very few few to to few, few, fine fine to to medium medium roots; roots;<br />
clear clear and and smooth smooth transition transition to to<br />
yellow yellow (2.5Y7/6); (2.5Y7/6); gravelly gravelly loamy loamy sand; sand; few few (I (I 5%) 5%) medium medium promin<strong>en</strong>t promin<strong>en</strong>t clear clear<br />
7.5YR5/8 7.5YR5/8 mottles; mottles; moderately moderately coher<strong>en</strong>t coher<strong>en</strong>t structure; structure; few few fine fine roots; roots; gradual gradual<br />
and and smooth smooth transition transition to to<br />
grey grey (IG6/5GY); (IG6/5GY); fine fine sand; sand; few few (5%) (5%) medium medium distinct distinct diffuse diffuse 7.5YR5/8 7.5YR5/8<br />
mottles; mottles; weakly weakly to to moderately moderately coher<strong>en</strong>t coher<strong>en</strong>t structure; structure; few few fine fine roots. roots.<br />
Pr<strong>of</strong>ile Pr<strong>of</strong>ile 138 138<br />
Particle Particle size size distribution distribution<br />
Horizon Horizon Depth Depth (cm) (cm) % % <strong>of</strong> <strong>of</strong> fine fine earth; earth; in).lm in).lm<br />
pH pH<br />
w w<br />
Vl Vl<br />
PROFILE PROFILE 183 183<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: unit:<br />
Soil Soil classification:<br />
classification:<br />
Description: Description:<br />
Location: Location:<br />
Elevation: Elevation:<br />
Landforrn Landforrn and and slope: slope:<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material:<br />
Vegetation: Vegetation:<br />
Drainage: Drainage:<br />
Soil: Soil:<br />
Depth Depth (cm) (cm) Hor. Hor.<br />
0- 0- 3 3 Ah Ah<br />
3-15 3-15 BA BA<br />
15-47 15-47 C C<br />
47-70 47-70 er er<br />
E E in in Dpd Dpd<br />
Dystric Dystric Fluvisol Fluvisol (FAO) (FAO)<br />
Fluvaqu<strong>en</strong>t Fluvaqu<strong>en</strong>t (Soil (Soil Taxonomy) Taxonomy)<br />
On On 26-07-95 26-07-95 by by Gerard Gerard Hazeu Hazeu<br />
About About 2 2 km km NE NE <strong>of</strong>Obo'otomba <strong>of</strong>Obo'otomba village; village; 3°04'11 3°04'11 Nand Nand 10°35'68 10°35'68 E E<br />
Unknown Unknown<br />
Undulating Undulating dissected dissected erosional erosional plain; plain; valley valley bottom bottom<br />
Alluvial Alluvial deposits deposits derived derived from from gneisses gneisses and/or and/or migmatites migmatites <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong><br />
Precambrian Precambrian shield shield<br />
Forest Forest<br />
Poorly Poorly drained drained<br />
Moderately Moderately deep, deep, grey grey to to white white sand sand with with very very dark dark brown brown topsoil topsoil<br />
Description Description<br />
very very dark dark brown brown (I (I OYR2/2); OYR2/2); sandy sandy clay clay loam; loam; moderately moderately coher<strong>en</strong>t; coher<strong>en</strong>t; very very<br />
friable, friable, non non stid:y, stid:y, slightly slightly plastic plastic and and weakly weakly smeary; smeary; few few fine fine to to medium medium<br />
roots; roots; clear clear and and smooth smooth transition transition to to<br />
light light yellowish yellowish grey grey (IOYR6/2); (IOYR6/2); slightly slightly gravelly gravelly coarse coarse sand; sand; weakly weakly<br />
coher<strong>en</strong>t coher<strong>en</strong>t single single grain; grain; loose, loose, non non sticky sticky and and non non plastic; plastic; few few very very fine fine to to<br />
fine fine roots; roots; clear clear and and smooth smooth transition transition to to<br />
dark dark yellowish yellowish brown brown (IOYR3/4); (IOYR3/4); slightly slightly gravelly gravelly loamy loamy sand; sand; moderately moderately<br />
coher<strong>en</strong>t; coher<strong>en</strong>t; very very friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; no no roots; roots; abrupt abrupt<br />
and and smooth smooth transition transition to to<br />
(IG7/5GY); (IG7/5GY); slightly slightly gravelly, gravelly, slightly slightly stony stony sandy sandy loam; loam; strongly strongly coher<strong>en</strong>t coher<strong>en</strong>t<br />
porous porous massive massive structure; structure; friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; no no<br />
roots. roots.<br />
Pr<strong>of</strong>ile Pr<strong>of</strong>ile 183 183<br />
Particle Particle size size distribution distribution<br />
Horizon Horizon Depth Depth (cm) (cm) % % <strong>of</strong> <strong>of</strong> fine fine earth; earth; in in Ilm Ilm<br />
pH pH<br />
w<br />
0\<br />
PROFILE 184<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit: unit:<br />
Soil classification:<br />
classification:<br />
Description:<br />
Location:<br />
Elevation: Elevation:<br />
Landform and slope:<br />
Par<strong>en</strong>t material:<br />
Vegetation:<br />
Vegetation:<br />
Drainage: Drainage:<br />
Soil:<br />
Depth Depth (cm) (cm) 1I0r.<br />
0- 3 Ah<br />
3-13 3-13 Acr Acr<br />
13-43 Cri<br />
43-66 43-66 Cr2<br />
E in Dpd<br />
Dystric Dystric Fluvisol (FAO) (FAO)<br />
Psammaqu<strong>en</strong>t (Soil Taxonomy) Taxonomy)<br />
On On 26-07-95 by Gerard lIazeu<br />
About 2 km NE <strong>of</strong>Obo'otomba village; 3°04'11 Nand 10°35'68 E<br />
Unknown<br />
Undulating Undulating dissected erosional plain; valley bottom<br />
Alluvial deposits derived from gneisses and/or migmatites <strong>of</strong> <strong>the</strong><br />
Precambrian Precambrian shield shield<br />
Forest Forest<br />
Poorly drained<br />
Deep, grey to white sand with very dark brown topsoil<br />
Description<br />
very dark dark brown brown (IOYR2/2); sandy sandy loam; moderately coher<strong>en</strong>t; coher<strong>en</strong>t; slightly<br />
stick)" slightly plastic and weakly smeary; many to abundant, very fine to<br />
fine roots; clear and smooth smooth transition to<br />
grey (I OYR5/1); loamy loamy fine sand; weakly weakly coher<strong>en</strong>t coher<strong>en</strong>t single grain; very<br />
friable, non sticky and slightly plastic; very few to few, very fine to fine<br />
roots; gradual and wavy transition to<br />
white (lOYR8/1); slightly gravelly loamy medium sand; weakly coher<strong>en</strong>t<br />
single grain; very friable, non sticky and non plastic; no roots; gradual and<br />
smooth transition to<br />
light grey (IOYR 7 /I); slightly gravelly, slightly stony loamy coarse sand;<br />
weakly coher<strong>en</strong>t single single grain; grain; very friable, non sticky and slightly plastic;<br />
no roots.<br />
Horizon<br />
Depth Depth (cm) Pr<strong>of</strong>ile Pr<strong>of</strong>ile 184<br />
Particle size distribution<br />
% % <strong>of</strong> fine earth; earth; in in um urn<br />
pH<br />
PROFILE PROFILE 203 203<br />
Leg<strong>en</strong>d Leg<strong>en</strong>d unit unit E E in in Cu2 Cu2<br />
Soil Soil classification: classification: Dystric Dystric Fluvisol Fluvisol (FAO) (FAO)<br />
Lythic Lythic Endoaqu<strong>en</strong>t Endoaqu<strong>en</strong>t (Soil (Soil Taxonomy) Taxonomy)<br />
Description:<br />
Description:<br />
On On 10-08-95 10-08-95 by by Gerard Gerard Ilazeu Ilazeu<br />
Location: Location:<br />
About About 1.5 1.5 km km S S <strong>of</strong> <strong>of</strong> Engomba Engomba village; village; 3 3 °04'84 °04'84 Nand Nand 10°39'45 10°39'45 E E<br />
Elevation: Elevation:<br />
340 340 m m<br />
Landform Landform and and slope: slope: Rolling Rolling uplands; uplands; valley valley bottom bottom<br />
Par<strong>en</strong>t Par<strong>en</strong>t material: material: Alluvial Alluvial deposits deposits derived derived from from gneisses gneisses <strong>of</strong> <strong>of</strong> <strong>the</strong> <strong>the</strong> Precambrian Precambrian shield shield<br />
Vegetation: Vegetation:<br />
Forest Forest<br />
Drainage: Drainage:<br />
Poorly Poorly drained drained<br />
Soil: Soil:<br />
Moderately Moderately deep, deep, grey grey sandy sandy loam loam with with very very dark dark brown brown topsoil topsoil<br />
Depth Depth (cm) (cm)<br />
0- 0- 4 4<br />
4-15 4-15<br />
15-43 15-43<br />
43-68 43-68<br />
Hor. Hor.<br />
Description Description<br />
Ah Ah very very dark dark brown brown (IOYR2/2); (IOYR2/2); sand; sand; moderately moderately coher<strong>en</strong>t; coher<strong>en</strong>t; very very friable, friable,<br />
slightly slightly stick)', stick)', slightly slightly plastic plastic and and weakly weakly smeary; smeary; common common to to many, many, very very<br />
fine fine to to fine fine roots; roots; clear clear and and smooth smooth transition transition to to<br />
BA BA light light yellowish yellowish brown brown (2.5Y6/4); (2.5Y6/4); slightly slightly gravelly gravelly sandy sandy loam; loam; weak weak very very<br />
fine fine subangular subangular blocky; blocky; friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; few few to to<br />
common, common, very very fine fine to to coarse coarse roots; roots; clear clear and and smooth smooth transition transition to to<br />
Bolr Bolr light light yellowish yellowish brown brown (2.5Y6/3); (2.5Y6/3); gravelly gravelly and and slightly slightly stony stony sandy sandy loam; loam;<br />
few few {I {I 0%) 0%) fine fine to to medium, medium, distinct distinct clear clear 7.5YR6/8 7.5YR6/8 mottles; mottles; weak weak very very fine fine<br />
subangular subangular blocky; blocky; friable, friable, slightly slightly sticky sticky and and slightly slightly plastic; plastic; few few to to<br />
common, common, very very fine fine to to coarse coarse roots; roots; abrupt abrupt and and irregular irregular transition transition to to<br />
CB CB grey grey (2.5Y6/1); (2.5Y6/1); gravelly, gravelly, sandy sandy loam loam and and rock rock boulders; boulders; many many (25%) (25%)<br />
medium medium distinct distinct clear clear 7.5YR5/8 7.5YR5/8 mottles; mottles; moderately moderately coher<strong>en</strong>t coher<strong>en</strong>t porous porous<br />
massive massive structure; structure; no no roots. roots.<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bolr Bolr<br />
CB CB<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bolr Bolr<br />
CB CB<br />
Horizon Horizon<br />
Ah Ah<br />
BA BA<br />
Bolr Bolr<br />
CB CB<br />
Pr<strong>of</strong>ile Pr<strong>of</strong>ile 203 203<br />
Particle Particle size size distribution distribution<br />
Depth Depth (cm) (cm) % % <strong>of</strong>fine <strong>of</strong>fine earth; earth; in).lm in).lm<br />
pH pH<br />
00<br />
M
ANNEX V Vegetation data<br />
ANNEX V Vegetation data<br />
V.A List <strong>of</strong> id<strong>en</strong>tified plant species recorded in <strong>the</strong> TCP research area<br />
V.A List <strong>of</strong> id<strong>en</strong>tified plant species recorded in <strong>the</strong> TCP research area<br />
V.B Summary table <strong>of</strong> <strong>the</strong> plant communities in <strong>the</strong> TCP research area<br />
V.B Summary table <strong>of</strong> <strong>the</strong> plant communities in <strong>the</strong> TCP research area<br />
139<br />
139
V.B Summary table <strong>of</strong> <strong>the</strong> plant communities in <strong>the</strong> TCP research area<br />
V.B Summary table <strong>of</strong> <strong>the</strong> plant communities in <strong>the</strong> TCP research area<br />
Distribution <strong>of</strong> plant species in <strong>the</strong> differ<strong>en</strong>t plant communities in <strong>the</strong> TCP research area. The first<br />
part concerns <strong>the</strong> differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> plant communities. In <strong>the</strong> second part, <strong>the</strong> distribution<br />
Distribution <strong>of</strong> plant species in <strong>the</strong> differ<strong>en</strong>t plant communities in <strong>the</strong> TCP research area. The first<br />
part concerns <strong>the</strong> differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> plant communities. In <strong>the</strong> second part, <strong>the</strong> distribution<br />
<strong>of</strong> <strong>the</strong> non-differ<strong>en</strong>tiating species is pres<strong>en</strong>ted in alphabetical order. Species pres<strong>en</strong>ce is indicated<br />
<strong>of</strong> <strong>the</strong> non-differ<strong>en</strong>tiating species is pres<strong>en</strong>ted in alphabetical order. Species pres<strong>en</strong>ce is indicated<br />
as relative frequ<strong>en</strong>cy; i.e. number <strong>of</strong> releves in <strong>the</strong> plant community in which <strong>the</strong> species is found.<br />
The lists <strong>of</strong> both differ<strong>en</strong>tial and non-differ<strong>en</strong>tial species include taxonomic <strong>en</strong>tities which are in<br />
fact clusters <strong>of</strong> species. These clusters are indicated by <strong>the</strong> suffix 'group' (gr).<br />
as relative frequ<strong>en</strong>cy; i.e. number <strong>of</strong> reI eves in <strong>the</strong> plant community in which <strong>the</strong> species is found.<br />
The lists <strong>of</strong> both differ<strong>en</strong>tial and non-differ<strong>en</strong>tial species include taxonomic <strong>en</strong>tities which are in<br />
fact clusters <strong>of</strong> species. These clusters are indicated by <strong>the</strong> suffix 'group' (gr).<br />
Plant communities: I = Maran<strong>the</strong>s-Anisophyllea community; <strong>II</strong>a = Podococcus-Polyalthia<br />
community; lIb = Strombosia-Polyalthia community; <strong>II</strong>c = Diospyros-Polyalthia community; <strong>II</strong>I<br />
Plant communities: I = Maran<strong>the</strong>s-Anisophyllea community; <strong>II</strong>a = Podococcus-Polyalthia<br />
community; lIb = Strombosia-Polyalthia community; <strong>II</strong>c = Diospyros-Polyalthia community; <strong>II</strong>I<br />
= Carapa-Mitragyna community; IV = Xylopia-Musanga community; and V = Macaranga<br />
= Carapa-Mitragyna community; IV = Xylopia-Musanga community; and V = Macaranga<br />
Chromola<strong>en</strong>a community. Frequ<strong>en</strong>cy classes: r= Ix; += 1-9%; 1= 10-19%; <strong>II</strong>=20-39%; <strong>II</strong>I=40-59%;<br />
IV=60-79% and V=80-1 00%. An indication <strong>of</strong> <strong>the</strong> growth form is added: LT=large tree (diameter<br />
at breast height (dbh) > 60cm; total height (H) > 40m); MT=medium-sized tree (dbh 20-60cm; H<br />
15-40m); ST=sma<strong>II</strong> tree (dbh 5-20cm; H < 15m); S=shrub (dbh< 5; H< 10; <strong>of</strong>t<strong>en</strong> multiple stems);<br />
WC=woody climber; NC=non-woody climber or vine; PL=palmoid liana; H=terrestrial herb<br />
(broad leaved); GH=graminoid herb; P=(acaulesc<strong>en</strong>t) palm; TF=tree fern.<br />
Chromola<strong>en</strong>a community. Frequ<strong>en</strong>cy classes: FIx; +=1-9%; 1=10-19%; <strong>II</strong>=20-39%; <strong>II</strong>I=40-59%;<br />
IV=60-79% and V=80-1 00%. An indication <strong>of</strong> <strong>the</strong> growth form is added: LT=large tree (diameter<br />
at breast height (dbh) > 60cm; total height (H) > 40m); MT=medium-sized tree (dbh 20-60cm; H<br />
I5-40m); ST=small tree (dbh 5-20cm; H < 15m); S=shrub (dbh< 5; H< 10; <strong>of</strong>t<strong>en</strong> multiple stems);<br />
WC=woody climber; NC=non-woody climber or vine; PL=palmoid liana; H=terrestrial herb<br />
(broadleaved); GH=graminoid herb; P=(acaulesc<strong>en</strong>t) palm; TF=tree fern.<br />
1. Differ<strong>en</strong>tial species<br />
1. Differ<strong>en</strong>tial species<br />
Vegetation type<br />
Vegetation type<br />
Nnmber <strong>of</strong> releves<br />
N nmber <strong>of</strong> rei eves<br />
la<br />
11<br />
11<br />
13<br />
lIb <strong>II</strong>c <strong>II</strong>I IV<br />
23 21 12 16<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Maran<strong>the</strong>s-Anisophyllea community (I)<br />
Drypetes gr 1 V <strong>II</strong> I + +<br />
Anisophy<strong>II</strong>ea polyneura V <strong>II</strong> <strong>II</strong> r +<br />
Scorodophloeus z<strong>en</strong>keri IV <strong>II</strong> + + +<br />
Maran<strong>the</strong>s glabra IV<br />
Gambeya grl IV <strong>II</strong> I I I<br />
Baphia leptobotrys HI I I I + I<br />
Cola atti<strong>en</strong>sis HI + + +<br />
Diospyros hoyleana <strong>II</strong>I + I +<br />
Garcinia lucida <strong>II</strong> r r<br />
Anopyxis klaineana <strong>II</strong><br />
Polyceratocarpus parviflorus <strong>II</strong> + r<br />
Agelaea hirsuta <strong>II</strong> +<br />
Diospyros crassiflora <strong>II</strong> + r<br />
Xylopia quintasii I r<br />
Pachypodanthum barteri I<br />
Majidea fosteri I<br />
Strychnos hirsuta I<br />
Pol ia cond<strong>en</strong>sata I<br />
Olax subscopioidea I +<br />
Dicranolepis sp I I +<br />
la<br />
11<br />
11<br />
13<br />
V Growth form<br />
18<br />
ST<br />
+ LT<br />
+ LT<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Maran<strong>the</strong>s-Anisophyllea community (I) and <strong>the</strong> Podococcus<br />
Polyalthia community (Iia)<br />
Monopetalanthus grl IV <strong>II</strong>I <strong>II</strong> I <strong>II</strong> +<br />
Raphia spI (cf. regalis) IV IV + + P<br />
Geophila sp I <strong>II</strong> <strong>II</strong> r + H<br />
149<br />
lIb <strong>II</strong>c <strong>II</strong>I IV<br />
23 21 12 16<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Maran<strong>the</strong>s-Anisophyllea community (I)<br />
Drypetes gr 1 V <strong>II</strong> I + +<br />
AnisophylIea polyneura V <strong>II</strong> <strong>II</strong> r +<br />
Scorodophloeus z<strong>en</strong>keri IV <strong>II</strong> + + +<br />
Maran<strong>the</strong>s glabra IV<br />
Gambeya grI IV <strong>II</strong> I I I<br />
Baphia leptobotrys HI I I I + I<br />
Cola atti<strong>en</strong>sis HI + + +<br />
Diospyros hoyleana <strong>II</strong>I + I +<br />
Garcinia lucida <strong>II</strong> r r<br />
Anopyxis klaineana <strong>II</strong><br />
Polyceratocarpus parviflorus <strong>II</strong> + r<br />
Agelaea hirsuta <strong>II</strong> +<br />
Diospyros crassiflora <strong>II</strong> + r<br />
Xylopia quintasii I r<br />
Pachypodanthum barteri I<br />
Majidea fosteri I<br />
Strychnos hirsuta I<br />
Polia cond<strong>en</strong>sata I<br />
Olax subscopioidea I +<br />
Dicranolepis spI I +<br />
V Growth form<br />
18<br />
ST<br />
+ LT<br />
+ LT<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Maran<strong>the</strong>s-Anisophyllea community (I) and <strong>the</strong> Podococcus<br />
Polyalthia community (Iia)<br />
Monopetalanthus gr I IV <strong>II</strong>I <strong>II</strong> I <strong>II</strong> +<br />
Raphia spl (cf. regalis) IV IV + + P<br />
Geophila sp I <strong>II</strong> <strong>II</strong> r + H<br />
149<br />
MT<br />
MT<br />
MT<br />
MT<br />
MT<br />
ST<br />
ST<br />
ST<br />
LT<br />
MT<br />
ST<br />
ST<br />
ST<br />
LT<br />
MT<br />
MT<br />
WL<br />
WL<br />
MT<br />
MT<br />
MT<br />
MT<br />
LT<br />
MT<br />
LT<br />
MT<br />
WC<br />
H<br />
WC<br />
H<br />
MT<br />
MT<br />
ST<br />
ST
Vegetation type la U lIb lIe <strong>II</strong>I IV V Growth form<br />
Vegetation type la 11 lIb lIe <strong>II</strong>I IV V Growth form<br />
Number <strong>of</strong> releves 11 13 23 21 12 16 18<br />
Number <strong>of</strong> rei eves 11 13 23 21 12 16 18<br />
Acioa staudtii Il r MT<br />
Drypetes leon<strong>en</strong>sis Il ST<br />
Mapania amplivaginata <strong>II</strong> GH<br />
Toubaouate brevipaniculata I I + LT<br />
Begonia grl I I r + H<br />
Acioa staudtii Il r MT<br />
Drypetes leon<strong>en</strong>sis Il ST<br />
Mapania amplivaginata <strong>II</strong> GH<br />
Toubaouate brevipaniculata + LT<br />
Begonia grI r + H<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Podococcus-Polyalthi community (<strong>II</strong>a)<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Podococcus-Polyalthi community (<strong>II</strong>a)<br />
Hym<strong>en</strong>ostegia afzelii IV I r MT<br />
Podococcus barteri + <strong>II</strong>I I + I P<br />
Crotonogyne preussii + <strong>II</strong> r S<br />
Tabernaemontana sp 1 + <strong>II</strong> r + ST<br />
Culcasia dinklagei + <strong>II</strong> H<br />
Duboscia macrocarpa + <strong>II</strong> r r + LT<br />
Petersianthus africanus <strong>II</strong> r r + LT<br />
Rhaptopetalum sp I I ST<br />
Hym<strong>en</strong>ostegia afzelii IV I r MT<br />
Podococcus barteri + <strong>II</strong>I I + I P<br />
Crotonogyne preussii + <strong>II</strong> r S<br />
Tabernaemontana sp 1 + 11 r + ST<br />
Culcasia dinklagei + <strong>II</strong> H<br />
Duboscia macrocarpa + <strong>II</strong> r r + LT<br />
Petersianthus africanus <strong>II</strong> r r + LT<br />
Rhaptopetalum sp 1 I ST<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Maran<strong>the</strong>s-Anisophyllea community (I), <strong>the</strong> Podococcus-Polyalthia<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Maran<strong>the</strong>s-Anisophyllea community (I), <strong>the</strong> Podococcus-Polyalthia<br />
community (Ua), and <strong>the</strong> Strombosia-Polyalthia community (lIb)<br />
community (<strong>II</strong>a), and <strong>the</strong> Strombosia-Polyalthia community (lIb)<br />
TrecuIia obovoidea V <strong>II</strong>I V + I + MT<br />
Calpocalyx gr 1 <strong>II</strong> I I r<br />
Treculia obovoidea V <strong>II</strong>I V + I + MT<br />
Cal pocal yx gr 1 <strong>II</strong> I I r<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Maran<strong>the</strong>s-Anisophyllea community (I), and <strong>the</strong> Polyalthia<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Maran<strong>the</strong>s-Anisophyllea community (I), and <strong>the</strong> Polyalthia<br />
community group (11)<br />
community group (11)<br />
Ptychopetalum petiolatum <strong>II</strong>I IV <strong>II</strong>I <strong>II</strong>I + 11 I MT<br />
Sorindeia sp I <strong>II</strong> <strong>II</strong> 11 <strong>II</strong> +<br />
Symphonia globulifera I I + I MT<br />
Dichostemma glaucesc<strong>en</strong>s I <strong>II</strong>I 11 I + MT<br />
Ptychopetalum petiolatum <strong>II</strong>I IV <strong>II</strong>I <strong>II</strong>I + 11 I MT<br />
Sorindeia sp 1 <strong>II</strong> <strong>II</strong> 11 <strong>II</strong> +<br />
Symphonia globulifera I I + I MT<br />
Dichostemma glaucesc<strong>en</strong>s I <strong>II</strong>I 11 I + MT<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Polyalthia community group (11)<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Polyalthia community group (11)<br />
Polyalthia suaveol<strong>en</strong>s IV IV IV 11 I MT<br />
Grossera gr 1 <strong>II</strong> IV IV IV I <strong>II</strong>I +<br />
Scaphopetalum blackii <strong>II</strong> IV IV <strong>II</strong>I 11 + I ST<br />
PIagiostyles africana <strong>II</strong> IV IV IV <strong>II</strong>I I + MT<br />
DiaIium grl <strong>II</strong> <strong>II</strong>I IV IV <strong>II</strong> +<br />
Agelaea spI <strong>II</strong> <strong>II</strong> <strong>II</strong>I + +<br />
Tricalysia gr I <strong>II</strong>I I <strong>II</strong>I + + S<br />
Desbordesia glaucesc<strong>en</strong>s <strong>II</strong> <strong>II</strong>I + + + LT<br />
Diospyros bipind<strong>en</strong>sis <strong>II</strong> <strong>II</strong> <strong>II</strong> +<br />
Diospyros obliquifolia + <strong>II</strong> 11 I + ST<br />
Guarea grl Il<br />
Carpolobia grl + <strong>II</strong> <strong>II</strong> + + I ST<br />
Antidesma laciantum <strong>II</strong> + MT<br />
Erythrophleum ivor<strong>en</strong>se <strong>II</strong> <strong>II</strong>I + + LT<br />
Polyalthia suaveol<strong>en</strong>s IV IV IV <strong>II</strong> I MT<br />
Grossera gr 1 <strong>II</strong> IV IV IV I <strong>II</strong>I +<br />
Scaphopetalum blackii <strong>II</strong> IV IV <strong>II</strong>I <strong>II</strong> + I ST<br />
Plagiostyles africana <strong>II</strong> IV IV IV <strong>II</strong>I I + MT<br />
DiaIium grl <strong>II</strong> <strong>II</strong>I IV IV <strong>II</strong> +<br />
Agelaea sp 1 11 <strong>II</strong> <strong>II</strong>I + +<br />
Tricalysia grl 1<strong>II</strong> I <strong>II</strong>I + + S<br />
Desbordesia glaucesc<strong>en</strong>s <strong>II</strong> <strong>II</strong>I + + + LT<br />
Diospyros bipind<strong>en</strong>sis <strong>II</strong> <strong>II</strong> <strong>II</strong> +<br />
Diospyros obliquifolia + Il <strong>II</strong> I + ST<br />
Guarea grl <strong>II</strong><br />
Carpolobia grl + Il <strong>II</strong> + + I ST<br />
Antidesma laciantum 11 + MT<br />
Erythrophleum ivor<strong>en</strong>se <strong>II</strong> <strong>II</strong>I + + LT<br />
150<br />
150
Vegetation type la<br />
N umber <strong>of</strong> rei eves 23 21 12 16 18<br />
Vegetation type<br />
Number <strong>of</strong> releves<br />
11<br />
11<br />
13<br />
lIb <strong>II</strong>c <strong>II</strong>I IV V Growth form<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Strombosia-Polylthia community (lIb)<br />
Grewia coriacea + <strong>II</strong> r + I MT<br />
Saccoglottis gabon<strong>en</strong>sis I r + + LT<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Strombosia-Polyalthia community (lIb) and <strong>the</strong> Diospyros-<br />
PolyaIthia community (lIc)<br />
Calpocalyx dinklagei I HI HI I I<br />
MT<br />
Rinorea kamerun<strong>en</strong>sis <strong>II</strong> I HI IV + I<br />
ST<br />
Olax staudtii + <strong>II</strong> I + + ST<br />
Chrytranthus talbotii <strong>II</strong> n I + MT<br />
Klainedoxa gabon<strong>en</strong>sis I <strong>II</strong><br />
LT<br />
Lasian<strong>the</strong>ra africana + <strong>II</strong> <strong>II</strong>I I I<br />
S<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Diospyros-Polyalthia community (lIc)<br />
Diospyros suaveol<strong>en</strong>s + <strong>II</strong> I IV HI I<br />
Draca<strong>en</strong>a grl + + <strong>II</strong> I<br />
Picralina nitida + I <strong>II</strong><br />
Lasian<strong>the</strong>ra sp2 + r I<br />
Marantaceae sp 1 I<br />
Pycnocoma macrophylla I +<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Maran<strong>the</strong>s-Anisophyllea community (I), <strong>the</strong> Polyalthia community<br />
group (11), and <strong>the</strong> Carapa-Mitragyna community (Ill)<br />
Cola ficifolia I + <strong>II</strong> I I MT<br />
Strombosia pustulata I <strong>II</strong> IV <strong>II</strong>I <strong>II</strong> MT<br />
Mammea africana <strong>II</strong> + <strong>II</strong> r I LT<br />
Halopegia grl HI IV IV HI IV H<br />
Beilschmiedia gr2 I <strong>II</strong> <strong>II</strong> <strong>II</strong> <strong>II</strong> +<br />
Aphanocalyx grl I <strong>II</strong> I <strong>II</strong> I +<br />
Santiria trimera <strong>II</strong>I <strong>II</strong>I HI <strong>II</strong> <strong>II</strong> + MT<br />
Differ<strong>en</strong>tial species <strong>of</strong> all forest communities (I, 11, <strong>II</strong>I and IV)<br />
Calamus deeratus HI IV IV HI <strong>II</strong>I HI PL<br />
Palisota mannii HI IV IV <strong>II</strong> IV <strong>II</strong> H<br />
Strombosia grl <strong>II</strong>I IV <strong>II</strong> <strong>II</strong>I <strong>II</strong>I <strong>II</strong><br />
Scaphopetalum thonneri <strong>II</strong> IV <strong>II</strong>I <strong>II</strong> <strong>II</strong> I S<br />
Staudtia kamerun<strong>en</strong>sis <strong>II</strong> <strong>II</strong>I IV V I IV + LT<br />
Coula edulis <strong>II</strong> n <strong>II</strong>I <strong>II</strong> + I MT<br />
Rubiaceae spl <strong>II</strong>I <strong>II</strong>I <strong>II</strong> <strong>II</strong> I<br />
Beilschmiedia grl I I I <strong>II</strong> <strong>II</strong> I<br />
Rubiaceae gr2 <strong>II</strong>I IV <strong>II</strong> <strong>II</strong> I <strong>II</strong> +<br />
TetraberIinia bifoliata <strong>II</strong>I + <strong>II</strong> <strong>II</strong> <strong>II</strong> LT<br />
Draca<strong>en</strong>a phrynioides <strong>II</strong> I + <strong>II</strong> +<br />
Glossocalyx brevipes <strong>II</strong> + <strong>II</strong>I <strong>II</strong> + ST<br />
Dacryodes gr 1 <strong>II</strong> <strong>II</strong> <strong>II</strong> + I<br />
V oacanga gr 1 <strong>II</strong> <strong>II</strong>I <strong>II</strong> + + I<br />
la<br />
11<br />
Diospyros gr2 <strong>II</strong> HI <strong>II</strong> + <strong>II</strong><br />
Blighia welwitschii + <strong>II</strong> I I + <strong>II</strong> LT<br />
11<br />
13<br />
151<br />
lIb <strong>II</strong>c <strong>II</strong>I IV V Growth form<br />
23 21 12 16 18<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Strombosia-Polylthia community (lIb)<br />
Grewia coriacea + <strong>II</strong> r + I MT<br />
Saccoglottis gabon<strong>en</strong>sis I r + + LT<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Strombosia-Polyalthia community (lIb) and <strong>the</strong> Diospyros-<br />
PolyaIthia community (lIc)<br />
Calpocalyx dinklagei I HI HI I I<br />
MT<br />
Rinorea kamerun<strong>en</strong>sis n I HI IV + I<br />
ST<br />
Olax staudtii + <strong>II</strong> I + + ST<br />
Chrytranthus talbotii <strong>II</strong> <strong>II</strong> I + MT<br />
Klainedoxa gabon<strong>en</strong>sis I n<br />
I LT<br />
Lasian<strong>the</strong>ra africana + <strong>II</strong> <strong>II</strong>I I I<br />
S<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Diospyros-Polyalthia community (lIc)<br />
Diospyros suaveol<strong>en</strong>s + <strong>II</strong> I IV <strong>II</strong>I I<br />
Draca<strong>en</strong>a gr 1 + + n I<br />
Picralina nitida + I <strong>II</strong><br />
Lasian<strong>the</strong>ra sp2 + r I<br />
Marantaceae sp 1 I<br />
Pycnocoma macrophylla I +<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Maran<strong>the</strong>s-Anisophyllea community (I), <strong>the</strong> PolyaIthia community<br />
group (11), and <strong>the</strong> Carapa-Mitragyna community (Ill)<br />
Cola ficifolia I + n I I MT<br />
Strombosia pustulata I n IV <strong>II</strong>I <strong>II</strong> MT<br />
Mammea africana n + n r I LT<br />
Halopegia gr I <strong>II</strong>I IV IV <strong>II</strong>I IV H<br />
Beilschmiedia gr2 I <strong>II</strong> n n <strong>II</strong> +<br />
Aphanocalyx grl I <strong>II</strong> I n I +<br />
Santiria trimera <strong>II</strong>I <strong>II</strong>I <strong>II</strong>I <strong>II</strong> <strong>II</strong> + MT<br />
Differ<strong>en</strong>tial species <strong>of</strong> all forest communities (I, 11, <strong>II</strong>I and IV)<br />
Calamus deeratus HI IV IV HI <strong>II</strong>I HI PL<br />
Palisota mannii <strong>II</strong>I IV IV <strong>II</strong> IV <strong>II</strong> H<br />
Strombosia grl <strong>II</strong>I IV n <strong>II</strong>I <strong>II</strong>I <strong>II</strong><br />
Scaphopetalum thonneri n IV <strong>II</strong>I <strong>II</strong> <strong>II</strong> I S<br />
Staudtia kamerun<strong>en</strong>sis n <strong>II</strong>I IV V I IV + LT<br />
Coula edulis If If <strong>II</strong>I n + I MT<br />
Rubiaceae sp I <strong>II</strong>I HI If n I<br />
Beilschmiedia grl I I I n <strong>II</strong> I<br />
Rubiaceae gr2 <strong>II</strong>I IV n n I <strong>II</strong> +<br />
TetraberIinia bifoliata <strong>II</strong>I + <strong>II</strong> n <strong>II</strong> LT<br />
Draca<strong>en</strong>a phrynioides If I + <strong>II</strong> +<br />
Glossocalyx brevipes <strong>II</strong> + <strong>II</strong>I <strong>II</strong> + ST<br />
Dacryodes gr 1 <strong>II</strong> <strong>II</strong> <strong>II</strong> + I<br />
Voacanga gr 1 <strong>II</strong> <strong>II</strong>I <strong>II</strong> + +<br />
Diospyros gr2 <strong>II</strong> HI <strong>II</strong> + <strong>II</strong><br />
Blighia welwitschii + <strong>II</strong> I I + n LT<br />
151<br />
+<br />
+<br />
+<br />
+<br />
I<br />
+<br />
+<br />
+<br />
+<br />
MT<br />
MT<br />
MT<br />
MT<br />
H<br />
H<br />
S<br />
S
Vegetation type la <strong>II</strong> lIb <strong>II</strong>c <strong>II</strong>I IV V Growth form<br />
Vegetation type la <strong>II</strong> lIb <strong>II</strong>c <strong>II</strong>I IV V Growth form<br />
Number <strong>of</strong> rei eves 11 13 23 21 12 16 18<br />
Number <strong>of</strong> releves 11 13 23 21 12 16 18<br />
Diospyros gr I <strong>II</strong> <strong>II</strong>I I I + <strong>II</strong><br />
Costus <strong>en</strong>gleranus I I + + + H<br />
Stipularia africana + + <strong>II</strong> r I <strong>II</strong> H<br />
Diospyros gr 1 <strong>II</strong> <strong>II</strong>I I I + <strong>II</strong><br />
Costus <strong>en</strong>gleranus I I + + + H<br />
Stipularia africana + + <strong>II</strong> r I <strong>II</strong> H<br />
Differ<strong>en</strong>tial species <strong>of</strong> all plant communities except <strong>the</strong> Maran<strong>the</strong>s - Anisophyllea community<br />
Differ<strong>en</strong>tial species <strong>of</strong> all plant communities except <strong>the</strong> Maran<strong>the</strong>s - Anisophyllea community<br />
(I)<br />
(I)<br />
Scyphocephalium mannii <strong>II</strong> I <strong>II</strong> I LT<br />
Piptad<strong>en</strong>iastrum africanum I <strong>II</strong> <strong>II</strong>I <strong>II</strong> <strong>II</strong>I + LT<br />
Pterocarpus gr I <strong>II</strong> <strong>II</strong> <strong>II</strong> I I<br />
Nephthytis sp I + 1I <strong>II</strong> + <strong>II</strong> I I H<br />
Lophira alata I <strong>II</strong> <strong>II</strong> <strong>II</strong> <strong>II</strong> <strong>II</strong>I LT<br />
Scyphocephalium mannii <strong>II</strong> I <strong>II</strong> I LT<br />
Piptad<strong>en</strong>iastrum africanum I <strong>II</strong> <strong>II</strong>I <strong>II</strong> <strong>II</strong>I + LT<br />
Pterocarpus gr 1 <strong>II</strong> <strong>II</strong> <strong>II</strong> I I<br />
Nephthytis sp 1 + 1I <strong>II</strong> + <strong>II</strong> I I H<br />
Lophira alata I <strong>II</strong> Il <strong>II</strong> <strong>II</strong> <strong>II</strong>I LT<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Carapa - Mitragyna community (Ill), <strong>the</strong> Xylopia - Musanga<br />
community (IV), and <strong>the</strong> Macaranga - Chromola<strong>en</strong>a community (V)<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Carapa - Mitragyna community (Ill), <strong>the</strong> Xylopia - Musanga<br />
community (IV), and <strong>the</strong> Macaranga - Chromola<strong>en</strong>a community (V)<br />
Sterculia tragacantha I I <strong>II</strong> MT<br />
Sterculia tragacantha I I<br />
Leea guine<strong>en</strong>sis + <strong>II</strong> I <strong>II</strong> S<br />
Leea guine<strong>en</strong>sis + <strong>II</strong> I<br />
PaIisota hirsuta + I I<br />
Elaeis guine<strong>en</strong>sis + <strong>II</strong>I <strong>II</strong><br />
Palisota hirsuta + I I I H<br />
Elaeis guine<strong>en</strong>sis + <strong>II</strong>I <strong>II</strong> <strong>II</strong>I P<br />
Caloncoba welwitschii + r r I I <strong>II</strong> MT<br />
Caloncoba welwitschii + r r I I<br />
Raphia sp2 + + <strong>II</strong>I <strong>II</strong> <strong>II</strong> P<br />
Raphia sp2 + + <strong>II</strong>I <strong>II</strong><br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Carapa - Mytragyna community (Ill)<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Carapa - Mytragyna community (UI)<br />
Mitragyna stipulosa r V + + MT<br />
Mitragyna stipulosa r V +<br />
Carapa sp 1 <strong>II</strong>I<br />
Trichilia heudelotii . + I + <strong>II</strong>I I<br />
Diospyros preussii + r <strong>II</strong><br />
Rubiaceae sp2 <strong>II</strong><br />
Cya<strong>the</strong>a manniana <strong>II</strong><br />
Curcuma longa <strong>II</strong><br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Xylopia - Musanga community (IV)<br />
Palisota ambigua I + <strong>II</strong> <strong>II</strong> <strong>II</strong>I IV<br />
Xylopia grl + <strong>II</strong> I <strong>II</strong> IV<br />
Zanthoxylum gillettii + <strong>II</strong> <strong>II</strong> I <strong>II</strong> IV<br />
Thaumatococcus danielii I I I IV<br />
Megaphrynium r I <strong>II</strong>I<br />
macrostachyum?<br />
Ancistrophyllum 0 r <strong>II</strong> <strong>II</strong>I<br />
secundiflorum<br />
Phyllanthus discoideus <strong>II</strong> I <strong>II</strong>I<br />
Ricinod<strong>en</strong>dron heudelotti + + <strong>II</strong><br />
Massularia acuminata + + I<br />
Caloncoba brevipes<br />
152<br />
<strong>II</strong><br />
<strong>II</strong><br />
I<br />
<strong>II</strong>I<br />
<strong>II</strong><br />
<strong>II</strong><br />
+<br />
I<br />
+<br />
<strong>II</strong><br />
<strong>II</strong><br />
<strong>II</strong>I<br />
<strong>II</strong><br />
<strong>II</strong><br />
I<br />
+<br />
MT<br />
S<br />
H<br />
P<br />
MT<br />
P<br />
MT<br />
MT<br />
Carapa spl <strong>II</strong>I MT<br />
Trichilia heudelotii . + I + <strong>II</strong>I I I ST<br />
Diospyros preussii + r <strong>II</strong> MT<br />
Rubiaceae sp2 <strong>II</strong><br />
Cya<strong>the</strong>a manniana <strong>II</strong> + TF<br />
Curcuma longa <strong>II</strong> GH<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Xylopia - Musanga community (IV)<br />
Palisota ambigua I + <strong>II</strong> <strong>II</strong> <strong>II</strong>I IV <strong>II</strong> H<br />
Xylopia grl + <strong>II</strong> I <strong>II</strong> IV <strong>II</strong><br />
Zanthoxylum gillettii + <strong>II</strong> <strong>II</strong> I <strong>II</strong> IV <strong>II</strong>I MT<br />
Thaumatococcus danielii I I I IV <strong>II</strong> H<br />
Megaphrynium r I <strong>II</strong>I <strong>II</strong> H<br />
macrostachyum?<br />
Ancistrophyllum 0 r <strong>II</strong> <strong>II</strong>I PL<br />
secundiflorum<br />
Phyllanthus discoideus <strong>II</strong> I <strong>II</strong>I I MT<br />
Ricinod<strong>en</strong>dron heudelotti + + <strong>II</strong> + LT<br />
Massularia acuminata + + I ST<br />
Caloncoba brevipes MT<br />
152<br />
ST<br />
MT<br />
TF<br />
GH<br />
H<br />
MT<br />
H<br />
H<br />
PL<br />
MT<br />
LT<br />
ST<br />
MT
Vegetation type<br />
Vegetation type<br />
Number <strong>of</strong> rei eves<br />
Number <strong>of</strong> rei eves<br />
la<br />
11<br />
11<br />
13<br />
lib <strong>II</strong>c <strong>II</strong>I IV<br />
23 21 12 16<br />
V Growth form<br />
18<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Diospyros - PolyaIthia community (lIc), <strong>the</strong> Xylopia - Musanga<br />
community (IV), and <strong>the</strong> Macaranga - Chromola<strong>en</strong>a community (V)<br />
Hylod<strong>en</strong>dron gr 1 <strong>II</strong> <strong>II</strong>I <strong>II</strong> IV + IV I<br />
Ouratea flava + If + <strong>II</strong>I + ST<br />
Eribroma gr 1 + nr + n HI<br />
Terminalia superba <strong>II</strong> + n I LT<br />
Myrianthus arboreus r <strong>II</strong> n I MT<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Xylopia - Musanga community (IV) and <strong>the</strong> Macaranga -<br />
Chromola<strong>en</strong>a community (V)<br />
la<br />
11<br />
Musanga cecropioides + + r n IV IV MT<br />
Funtumia elastica I r r nr HI MT<br />
Rauvolfia macrophylla r + n n MT<br />
Vernonia conferta n I ST<br />
Macaranga gr2 I n ST<br />
Anthoc1eista schweinfurthii I I MT<br />
Hamikoa grl r + InS<br />
Mareya brevipes r I +<br />
Melastomataceae gr2 r r I n<br />
Anthoc1eista vogelii I n MT<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Macaranga - Chromola<strong>en</strong>a community (V)<br />
11<br />
13<br />
Macaranga grl n IV ST<br />
Chromola<strong>en</strong>a odorata + IV H<br />
Fern grl I <strong>II</strong> n + n IV H<br />
Costus violaceus 11 nr H<br />
Trifolium spl (cultivated) nr H<br />
Milicia excelsa r <strong>II</strong>I LT<br />
Manihot escul<strong>en</strong>ta (cult.) + HI S<br />
Anchomanes spl (cult.) + nr H<br />
Ceiba p<strong>en</strong>tandra + r + HI LT<br />
Rauvolfia vomitoria I HI ST<br />
Albizia zygia I + I I n nr LT<br />
Dioscorea bulbifera 11 NL<br />
Trema ori<strong>en</strong>talis<br />
ST<br />
Sc1eria barteri<br />
Dioscorea burkeliana<br />
Colocasia escul<strong>en</strong>ta (cult.)<br />
n<br />
Musa gr I (cultivated)<br />
Jateorhiza macrantha<br />
NL<br />
Trifolium sp I (cult.)<br />
n<br />
Brucea spl<br />
r + n<br />
Millettia macrophylla r r +<br />
n<br />
Tetrorchidium didymost. r<br />
n<br />
Harungana madagasc. r<br />
I MT<br />
Theobroma cacao (cult.)<br />
I ST<br />
153<br />
lib <strong>II</strong>c <strong>II</strong>I IV<br />
23 21 12 16<br />
+<br />
+<br />
11<br />
11<br />
11<br />
11<br />
11<br />
V Growth form<br />
18<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Diospyros - PolyaIthia community (lIc), <strong>the</strong> Xylopia - Musanga<br />
community (IV), and <strong>the</strong> Macaranga - Chromola<strong>en</strong>a community (V)<br />
Hylod<strong>en</strong>dron gr 1 <strong>II</strong> <strong>II</strong>I <strong>II</strong> IV + IV I<br />
Ouratea flava + If + nr + ST<br />
Eribroma gr 1 + HI + n HI<br />
Terminalia superba If + n I LT<br />
Myrianthus arboreus r If n I MT<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Xylopia - Musanga community (IV) and <strong>the</strong> Macaranga -<br />
Chromola<strong>en</strong>a community (V)<br />
Musanga cecropioides + + r n IV IV MT<br />
Funtumia elastica I r r nr HI MT<br />
Rauvolfia macrophylla r + n n MT<br />
Vernonia conferta n I ST<br />
Macaranga gr2 I n ST<br />
Anthoc1eista schweinfurthii I I MT<br />
Hamikoa grl r + I <strong>II</strong> S<br />
Mareya brevipes r I +<br />
Melastomataceae gr2 r r I <strong>II</strong><br />
Anthoc1eista vogelii I n MT<br />
Differ<strong>en</strong>tial species <strong>of</strong> <strong>the</strong> Macaranga - Chromola<strong>en</strong>a community (V)<br />
Macaranga grl n IV ST<br />
Chromola<strong>en</strong>a odorata + IV H<br />
Fern grl I 11 n + n IV H<br />
Costus violaceus 11 HI H<br />
Trifolium spl (cultivated) HI H<br />
Milicia excelsa r HI LT<br />
Manihot escul<strong>en</strong>ta (cult.) + <strong>II</strong>I S<br />
Anchomanes spl (cult.) + <strong>II</strong>I H<br />
Ceiba p<strong>en</strong>tandra + r + <strong>II</strong>I LT<br />
Rauvolfia vomitoria I <strong>II</strong>I ST<br />
Albizia zygia I + I I n <strong>II</strong>I LT<br />
Dioscorea bulbifera n NL<br />
Trema ori<strong>en</strong>talis<br />
ST<br />
Sc1eria barteri<br />
Dioscorea burkeliana<br />
Colocasia escul<strong>en</strong>ta (cult.)<br />
Musa gr I (cultivated)<br />
Jateorhiza macrantha<br />
Trifolium sp I (cult.)<br />
Brucea spl<br />
r +<br />
Millettia macrophylla r r +<br />
Tetrorchidium didymost. r<br />
Harungana madagasc. r<br />
I MT<br />
Theobroma cacao (cult.)<br />
I ST<br />
153<br />
+<br />
+<br />
n<br />
<strong>II</strong><br />
n<br />
n<br />
11<br />
<strong>II</strong><br />
n<br />
<strong>II</strong><br />
n<br />
GH<br />
GH<br />
WC<br />
WC<br />
H<br />
H<br />
HIS<br />
HIS<br />
NL<br />
MT<br />
MT
2. Non-differ<strong>en</strong>tial species<br />
2. Non-differ<strong>en</strong>tial species<br />
Vegetation type la lIa lIb lIe Illa IVa Va Growth form<br />
Vegetation type la <strong>II</strong>a lIb lIe Illa IVa Va Growth form<br />
Carapa grl <strong>II</strong>I <strong>II</strong> <strong>II</strong>I <strong>II</strong> <strong>II</strong> <strong>II</strong> I<br />
Uapaca guine<strong>en</strong>sis 1<strong>II</strong> IV <strong>II</strong>I 11 <strong>II</strong>I 11 11 LT<br />
Coelocaryon preussii <strong>II</strong>I <strong>II</strong>I IV V V IV 11 LT<br />
P<strong>en</strong>taclethra macrophylla <strong>II</strong> <strong>II</strong>I IV I 11 <strong>II</strong>I I MT<br />
Cercestis ivor<strong>en</strong>sis <strong>II</strong> <strong>II</strong> <strong>II</strong>I IV <strong>II</strong> <strong>II</strong>I <strong>II</strong> H<br />
Tabernaemontana crassa <strong>II</strong> <strong>II</strong>I <strong>II</strong>I IV I IV I MT<br />
Rubiaceae gr3 <strong>II</strong> <strong>II</strong>I <strong>II</strong>I 11 <strong>II</strong>I <strong>II</strong>I I S<br />
Trachyphrynium spl 11 <strong>II</strong> I 11 11 <strong>II</strong>I 11<br />
Haumania danckelmanniana I IV IV V <strong>II</strong>I V <strong>II</strong>I PL<br />
Pycnanthus angol<strong>en</strong>sis IV <strong>II</strong> IV <strong>II</strong>I IV <strong>II</strong>I LT<br />
Rhektophyllum grl <strong>II</strong> V IV IV V 11 H<br />
Enantia chlorantha <strong>II</strong> <strong>II</strong> I I I I MT<br />
Anthonotha macrophylla + <strong>II</strong> <strong>II</strong> IV <strong>II</strong>I <strong>II</strong>I <strong>II</strong> MT<br />
Homalium delicophyllus <strong>II</strong>I <strong>II</strong> I I I I 11 LT<br />
Guaduella grl <strong>II</strong>I I <strong>II</strong> <strong>II</strong>I I I I GH<br />
Alchornea floribunda I <strong>II</strong> I I + <strong>II</strong>I I WC<br />
Acacia p<strong>en</strong>nata + I + + I I WC<br />
Acroceras zizanioides I<br />
Aframomum grl + I I <strong>II</strong> <strong>II</strong> H<br />
Afrosersalisia cerasifera +<br />
Draca<strong>en</strong>a sp 1 + r I H<br />
Carapa grl <strong>II</strong>I <strong>II</strong> <strong>II</strong>I <strong>II</strong> <strong>II</strong> <strong>II</strong> I<br />
Uapaca guine<strong>en</strong>sis 1<strong>II</strong> IV <strong>II</strong>I 11 <strong>II</strong>I 11 11 LT<br />
Coelocaryon preussii <strong>II</strong>I <strong>II</strong>I IV V V IV 11 LT<br />
P<strong>en</strong>taclethra macrophylla <strong>II</strong> <strong>II</strong>I IV I 11 <strong>II</strong>I I MT<br />
Cercestis ivor<strong>en</strong>sis <strong>II</strong> <strong>II</strong> <strong>II</strong>I IV <strong>II</strong> <strong>II</strong>I <strong>II</strong> H<br />
Tabernaemontana crassa <strong>II</strong> <strong>II</strong>I <strong>II</strong>I IV I IV I MT<br />
Rubiaceae gr3 <strong>II</strong> <strong>II</strong>I <strong>II</strong>I <strong>II</strong> <strong>II</strong>I <strong>II</strong>I I S<br />
Trachyphrynium spl <strong>II</strong> <strong>II</strong> I <strong>II</strong> <strong>II</strong> <strong>II</strong>I <strong>II</strong><br />
Haumania danckelmanniana IV IV V <strong>II</strong>I V <strong>II</strong>I PL<br />
Pycnanthus angol<strong>en</strong>sis IV <strong>II</strong> IV <strong>II</strong>I IV <strong>II</strong>I LT<br />
Rhektophyllum grl <strong>II</strong> V IV IV V <strong>II</strong> H<br />
Enantia chlorantha <strong>II</strong> <strong>II</strong> I I I I MT<br />
Anthonotha macrophylla + <strong>II</strong> <strong>II</strong> IV <strong>II</strong>I <strong>II</strong>I <strong>II</strong> MT<br />
Homalium delicophyllus <strong>II</strong>I <strong>II</strong> I I I I <strong>II</strong> LT<br />
Guaduella grl <strong>II</strong>I I 11 <strong>II</strong>I I I I GH<br />
Alchornea floribunda I <strong>II</strong> I I + <strong>II</strong>I I WC<br />
Acacia p<strong>en</strong>nata + I + + I I WC<br />
Acroceras zizanioides I<br />
Aframomum grl + I I 11 <strong>II</strong> H<br />
Afrosersalisia cerasifera +<br />
Draca<strong>en</strong>a sp 1 + r I H<br />
Vegetation type la <strong>II</strong>a lIb lIe llla IVa Va Growth form<br />
Vegetation type la lIa lIb lie llla IVa Va Growth form<br />
Albizia adianthifolia + r I + LT<br />
Albizia glaberrima + LT<br />
Alchornea cordifolia I + WC<br />
Alchornea hirtella + r r S<br />
Allanblackia floribunda + r MT<br />
Allanblackia kisongui <strong>II</strong>I + <strong>II</strong>I <strong>II</strong> I <strong>II</strong> + MT<br />
Allanblackia montana + LT<br />
Allophyllus africanus r + ST<br />
Alstonia boonei + + LT<br />
Alstonia cong<strong>en</strong>sis + 11 I + I <strong>II</strong> 11 LT<br />
Angylocalyx oligophyllus + MT<br />
Angylocalyx z<strong>en</strong>keri + + + MT<br />
Antidesma v<strong>en</strong>osum + + r MT<br />
Antrocaryon klaineanum + r r 11 + LT<br />
Anubias hastifolia + H<br />
Aptandra z<strong>en</strong>keri ST<br />
Araliopsis soyauxii + + LT<br />
Aspilia africana I + I H<br />
Asystasia macrophylla r<br />
Bambusa arundinacea + GH<br />
Baphia laurifolia r MT<br />
Barteria fistulosa + r I I MT<br />
Albizia adianthifolia + r I + LT<br />
Albizia glaberrima + LT<br />
Alchornea cordifolia I + WC<br />
Alchornea hirtella + r r S<br />
Allanblackia floribunda + r MT<br />
Allanblackia kisongui <strong>II</strong>I + <strong>II</strong>I <strong>II</strong> I <strong>II</strong> + MT<br />
Allanblackia montana + LT<br />
Allophyllus africanus r + ST<br />
Alstonia boonei + + LT<br />
Alstonia cong<strong>en</strong>sis + <strong>II</strong> I + I <strong>II</strong> <strong>II</strong> LT<br />
Angylocalyx oligophyllus + MT<br />
Angylocalyx z<strong>en</strong>keri + + + MT<br />
Antidesma v<strong>en</strong>osum + + r MT<br />
Antrocaryon klaineanum + r r 11 + LT<br />
Anllbias hastifolia + H<br />
Aptandra z<strong>en</strong>keri ST<br />
Araliopsis soyallxii + + LT<br />
Aspilia africana I + I H<br />
Asystasia macrophylla r<br />
Bambusa arundinacea + GH<br />
Baphia laurifolia r MT<br />
Barteria fistlllosa + r I I MT<br />
154<br />
154
Vegetation type la <strong>II</strong>a lIb lIe IlIa IVa Va Growth form<br />
Vegetation type la <strong>II</strong>a lIb lIe IlIa IVa Va Growth form<br />
Begonia macrocarpa + H<br />
Begonia macrocarpa + H<br />
Begonia sciaphila + H<br />
Begonia sciaphila + H<br />
Berlinia bracteosa + I <strong>II</strong> I LT<br />
Berlinia bracteosa + I <strong>II</strong> I LT<br />
Berlinia confusa + LT<br />
Berlinia confusa + LT<br />
Blighia sapida + r MT<br />
Blighia sapida + r MT<br />
Bosqueia angol<strong>en</strong>sis + I<br />
Bosqueia angol<strong>en</strong>sis + I<br />
Brachystegia cynometroides + r LT<br />
Brachystegia cynometroides + r LT<br />
Brachystegia eurycoma r LT<br />
Brachystegia eurycoma r LT<br />
Brachystegia mildbraedii r LT<br />
Brachystephanus jaund<strong>en</strong>sis + + I H<br />
Brachystegia mildbraedii r LT<br />
Brachystephanus jaund<strong>en</strong>sis + + I H<br />
Br<strong>en</strong>ania Brieyi + MT<br />
Br<strong>en</strong>ania Brieyi + MT<br />
Bridelia micrantha + MT<br />
Bridelia micrantha + MT<br />
Buchholzia coriacea I + r MT<br />
Buchholzia coriacea I + r MT<br />
Caloncoba gilgiana + I MT<br />
Caloncoba gilgiana + I MT<br />
Caloncoba glauca + I I I MT<br />
Caloncoba zygas + MT<br />
Caloncoba glauca + I I I MT<br />
Caloncoba zygas + MT<br />
Canarium schweinfurthii + + + I I I LT<br />
Canarium schweinfurthii + + + I I I LT<br />
Canthium arnoldianum + MT<br />
Canthium palma + + MT<br />
Canthium arnoldianum + MT<br />
Canthium palma + + MT<br />
Carica papaya I S<br />
Carica papaya I S<br />
Celtis grl + <strong>II</strong> I I + I MT<br />
Celtis tessmannii + r LT<br />
Cephaelis sp 1 I + r I + H<br />
Cercestis congo<strong>en</strong>sis + H<br />
Cercestis kamerunianus I <strong>II</strong> I + H<br />
Celtis grl + <strong>II</strong> I I + I MT<br />
Celtis tessmannii + r LT<br />
Cephaelis sp 1 I + r I + H<br />
Cercestis congo<strong>en</strong>sis + H<br />
Cercestis kamerunianus I <strong>II</strong> I + H<br />
Chrytranthus seressii + r MT<br />
Chrytranthus sp 1 r ST<br />
Cleistopholis glauca + LT<br />
Cleistopholis pat<strong>en</strong>s + + + + <strong>II</strong> I LT<br />
Cnestis grisea r r +<br />
Chrytranthus seressii + r MT<br />
Chrytranthus sp 1 r ST<br />
Cleistopholis glauca + LT<br />
Cleistopholis pat<strong>en</strong>s + + + + <strong>II</strong> I LT<br />
Cnestis grisea r r +<br />
Coelocaryon spl +<br />
Coelocaryon sp 1 +<br />
Cola cauliflora r ST<br />
Cola cauliflora r ST<br />
Cola cordifolia <strong>II</strong> + I MT<br />
Cola grl I <strong>II</strong> <strong>II</strong> + I<br />
Cola cordifolia <strong>II</strong> + I MT<br />
Cola grl I <strong>II</strong> <strong>II</strong> + I<br />
Cola gr2 + + +<br />
Cola lepidota + + + ST<br />
Cola marsupium + + r + S<br />
Cola gr2 + + +<br />
Cola lepidota + + + ST<br />
Cola marsupium + + r + S<br />
Cola rostrata I I + + MT<br />
Cola rostrata I I + + MT<br />
Commelina cameroon<strong>en</strong>sis H<br />
Commelina cameroon<strong>en</strong>sis H<br />
Commelinaceae grl r + + H<br />
Commelinaceae grl r + + H<br />
Agelaea grl + +<br />
Agelaea grl + +<br />
Cnestis grl r<br />
Cnestis grl r<br />
Cordia plathythyrsa + LT<br />
Cordia plathythyrsa + LT<br />
Costus afer I + H<br />
Costus dinklagei I H<br />
Costus afer I + H<br />
Costus dinklagei I H<br />
Costus phaeotrichus r H<br />
Costus spl r I H<br />
Craterispermum laurinum r r + ST<br />
Costus phaeotrichus r H<br />
Costus spl r I H<br />
Craterispermum laurinum r r + ST<br />
155<br />
155
Vegetation type la lIa lib ne Ilia IVa Va Growth form<br />
Vegetation type la lIa lib lie Ilia IVa Va Growth form<br />
Craterispermum longifolium r ST<br />
Craterosiphon scand<strong>en</strong>s +<br />
Crotonogyne manniana + S<br />
Cyliodiscus gabun<strong>en</strong>sis + r + LT<br />
Mapania grl I I + GH<br />
Cyperus diffusus + GH<br />
Dacryodes edulis <strong>II</strong> <strong>II</strong> <strong>II</strong> <strong>II</strong> I MT<br />
Dacryodes klaineana r MT<br />
Detarium macrocarpllm + LT<br />
Didelotia brevipaniculata r + LT<br />
Didelotia unifoliolata + LT<br />
Diospyros conocarpa + r + ST<br />
Diospyros d<strong>en</strong>do + MT<br />
Discoglypremna caloneura + + r I + LT<br />
Distemonanthus b<strong>en</strong>tham. + <strong>II</strong> <strong>II</strong> + <strong>II</strong> <strong>II</strong> LT<br />
Dorst<strong>en</strong>ia picta + + H<br />
Dorst<strong>en</strong>ia subtriangularis + H<br />
Dorst<strong>en</strong>ia turbinata r H<br />
Draca<strong>en</strong>a cerasifera + HIS<br />
Draca<strong>en</strong>a sp 1<br />
Drypetes gabon<strong>en</strong>sis ST<br />
Drypetes gossweileri + r LT<br />
Drypetes molunduana r MT<br />
Drypetes sp 1 I r MT<br />
Duparquetia orchidacea + WC<br />
Entandrophragma angol<strong>en</strong>se + LT<br />
Entandrophragma utile + + LT<br />
Eriocoelum macrocarpum + + MT<br />
Erytroxylum mannii + I LT<br />
Eug<strong>en</strong>ia spl r<br />
Euphorbiaceae gr 1 + +<br />
Euphorbiaceae sp 1 +<br />
Ficlls exasperata r I LT<br />
Fillaeopsis discophora r LT<br />
Flacollrtiaceae sp 1 + <strong>II</strong> <strong>II</strong> + <strong>II</strong><br />
Gambeya perpulchra + MT<br />
Garcinia kola MT<br />
Garcinia mannii <strong>II</strong> <strong>II</strong>I <strong>II</strong> <strong>II</strong> I + ST<br />
Garcinia polyantha r r MT<br />
Garcinia staudtii + + MT<br />
Gard<strong>en</strong>ia sp I +<br />
Gilbertiod<strong>en</strong>dron brachyst. r LT<br />
Gilbertiod<strong>en</strong>dron dewevrei I + I LT<br />
Gilbertiod<strong>en</strong>dron grandifl. r LT<br />
Gilbertiod<strong>en</strong>dron ogoou<strong>en</strong>se + LT<br />
Glyphaea brevis + I ST<br />
Gossweilerod<strong>en</strong>dron balsam. + LT<br />
Gossweilerod<strong>en</strong>dron jOlleri + LT<br />
Craterispermum longifolium r ST<br />
Craterosiphol1 scand<strong>en</strong>s +<br />
Crotonogyne manniana + S<br />
Cyliodiscus gabun<strong>en</strong>sis + r + LT<br />
Mapania grl I I + GH<br />
Cyperus diffusus + GH<br />
Dacryodes edulis <strong>II</strong> <strong>II</strong> <strong>II</strong> <strong>II</strong> I MT<br />
Dacryodes klaineana r MT<br />
Detarium macrocarpum + LT<br />
Didelotia brevipaniculata r + LT<br />
Didelotia unifoliolata + LT<br />
Diospyros conocarpa + r + ST<br />
Diospyros d<strong>en</strong>do + MT<br />
Discoglypremna caloneura + + r I + LT<br />
Distemonanthus b<strong>en</strong>tham. + <strong>II</strong> <strong>II</strong> + <strong>II</strong> <strong>II</strong> LT<br />
Dorst<strong>en</strong>ia picta + + H<br />
Dorst<strong>en</strong>ia subtriangularis + H<br />
Dorst<strong>en</strong>ia turbinata r H<br />
Draca<strong>en</strong>a cerasifera + HIS<br />
Draca<strong>en</strong>a sp 1<br />
Drypetes gabon<strong>en</strong>sis ST<br />
Drypetes gossweileri + r LT<br />
Drypetes molunduana r MT<br />
Drypetes sp 1 I r MT<br />
Duparquetia orchidacea + WC<br />
Entandrophragma angol<strong>en</strong>se + LT<br />
Entandrophragma utile + + LT<br />
Eriocoelum macrocarpum + + MT<br />
Erytroxylum mannii + I LT<br />
Eug<strong>en</strong>ia spl r<br />
Euphorbiaceae gr 1 + +<br />
Euphorbiaceae sp 1 +<br />
Ficus exasperata r I LT<br />
Fillaeopsis discophora r LT<br />
Flacourtiaceae sp 1 + <strong>II</strong> 11 + <strong>II</strong><br />
Gambeya perpulchra + MT<br />
Garcinia kola MT<br />
Garcinia mannii <strong>II</strong> <strong>II</strong>I 11 11 I + ST<br />
Garcinia polyantha r r MT<br />
Garcinia staudtii + + MT<br />
Gard<strong>en</strong>ia sp I +<br />
Gilbertiod<strong>en</strong>dron brachyst. r LT<br />
Gilbertiod<strong>en</strong>dron dewevrei I + I LT<br />
Gilbertiod<strong>en</strong>dron grandifl. r LT<br />
Gilbertiod<strong>en</strong>dron ogoou<strong>en</strong>se + LT<br />
Glyphaea brevis + I ST<br />
Gossweilerod<strong>en</strong>dron balsam. + LT<br />
Gossweilerod<strong>en</strong>dron joueri + LT<br />
156<br />
156
Vegetation type la Ha lIb lIe IlIa IVa Va Growth form<br />
Vegetation type la Ha lib lie Ilia IVa Va Growth form<br />
Grossera macrantha I I r + MT<br />
Grossera paniculata r MT<br />
Guarea cedrata + + I + + LT<br />
Guibourtia tessmannii + LT<br />
Heckeldora spec. (HNC 49157) + ST<br />
Heisteria parvifolia + + I + ST<br />
Hexalobus crispiflorus + I r I MT<br />
Hunteria umbellata + r S<br />
Hym<strong>en</strong>ocardia heudelotii ST<br />
Hym<strong>en</strong>ostegia breteleri + MT<br />
Hypodaphnis z<strong>en</strong>keri + I <strong>II</strong> <strong>II</strong> MT<br />
Hypselodelphys spl r + H<br />
lodes kamerun<strong>en</strong>sis + + WC<br />
Irvingia gabon<strong>en</strong>sis + <strong>II</strong> <strong>II</strong> I + + LT<br />
Irvingia grandifolia + + r + LT<br />
Irvingia robur + + r I LT<br />
Isolona hexaloba + + MT<br />
Justica ext<strong>en</strong>sa + H<br />
Khaya ivor<strong>en</strong>sis + r LT<br />
Klainedoxa microphylla + I + r + LT<br />
Laccodiscus ferrugineus + r MT<br />
Landolphia spl <strong>II</strong> + r + NC<br />
Lasiodiscus spl r ST<br />
Lavigeria grJ I I <strong>II</strong> <strong>II</strong>I I <strong>II</strong> WC<br />
Lecaniodiscus cupanioides + MT<br />
Leptaulus daphnoides + ST<br />
Leptaulus z<strong>en</strong>keri + + r ST<br />
Leptonychia sp I ST<br />
Lovoa trichilioides I r + + + LT<br />
Macarangahurifolia + MT<br />
Macaranga occid<strong>en</strong>talis + WC<br />
Macaranga saccifera + WC<br />
Maesobotrya acuminata r ST<br />
Maesobotrya barteri + r MT<br />
Maesobotrya dus<strong>en</strong>ii + r r ST<br />
Maesobotrya staudtii I I r + I MT<br />
Maesopsis eminii + + + MT<br />
Mangifera indica + MT<br />
Mapania macrantha I + GH<br />
Maran<strong>the</strong>s chrysophylla + MT<br />
Marantochloa leucantha I + + H<br />
Mareyopsis longifolia 11 <strong>II</strong> 11 I I I MT<br />
Meiocarpidium grJ + + <strong>II</strong> 11 I +<br />
Melastomataceae grl + + + +<br />
Microcalamus barbinodis + + GH<br />
Microdesmis HNC 49201 + + ST<br />
Millettia spl r<br />
Monodora myristica + + r MT<br />
Grossera macrantha I I r + MT<br />
Grossera paniculata r MT<br />
Guarea cedrata + + I + + LT<br />
Guibourtia tessmannii + LT<br />
Heckeldora spec. (HNC 49157) + ST<br />
Heisteria parvifolia + + I + ST<br />
Hexalobus crispiflorus + I r I MT<br />
Hunteria umbellata + r S<br />
Hym<strong>en</strong>ocardia heudelotii ST<br />
Hym<strong>en</strong>ostegia breteleri + MT<br />
Hypodaphnis z<strong>en</strong>keri + I <strong>II</strong> <strong>II</strong> MT<br />
Hypselodelphys sp I r + H<br />
lodes kamerun<strong>en</strong>sis + + WC<br />
Irvingia gabon<strong>en</strong>sis + <strong>II</strong> <strong>II</strong> I + + LT<br />
Irvingia grandifolia + + r + LT<br />
Irvingia robur + + r I LT<br />
Isolona hexaloba + + MT<br />
Justica ext<strong>en</strong>sa + H<br />
Khaya ivor<strong>en</strong>sis + r LT<br />
Klainedoxa microphylla + I + r + LT<br />
Laccodiscus ferrugineus + r MT<br />
Landolphia spl <strong>II</strong> + r + NC<br />
Lasiodiscus sp 1 r ST<br />
Lavigeria grl I I <strong>II</strong> <strong>II</strong>I I <strong>II</strong> WC<br />
Lecaniodiscus cupanioides + MT<br />
Leptaulus daphnoides + ST<br />
Leptaulus z<strong>en</strong>keri + + r ST<br />
Leptonychia spI ST<br />
Lovoa trichilioides I r + + + LT<br />
Macaranga hurifolia + MT<br />
Macaranga occid<strong>en</strong>talis + WC<br />
Macaranga saccifera + WC<br />
Maesobotrya acuminata r ST<br />
Maesobotrya barteri + r MT<br />
Maesobotrya dus<strong>en</strong>ii + r r ST<br />
Maesobotrya staudtii I I r + I MT<br />
Maesopsis eminii + + + MT<br />
Mangifera indica + MT<br />
Mapania macrantha I + GH<br />
Maran<strong>the</strong>s chrysophylla + MT<br />
Marantochloa leucantha I + + H<br />
Mareyopsis longifolia 11 <strong>II</strong> 11 I I I MT<br />
Meiocarpidium grl + + <strong>II</strong> 11 I +<br />
Melastomataceae gr 1 + + + +<br />
Microcalamus barbinodis + + GH<br />
Microdesmis HNC 49201 + + ST<br />
Millettia sp 1 r<br />
Monodora myristica + + r MT<br />
157<br />
157
Vegetation type la lIa lib lie Ilia IVa Va Growth form<br />
Vegetation type la lIa lib lie Ilia IVa Va Growth form<br />
Monodora sp 1 r<br />
Mostuea brunoniste NC<br />
Mucuna flagellipes +<br />
Mussa<strong>en</strong>da sp 1 +<br />
Myrianthus serratus + + MT<br />
Napoleonaea sp 1 + ST<br />
Nauclea diderrichii + + LT<br />
Newbouldia laevis I I I 11<br />
Newtonia griffoniana + LT<br />
Nonthospondias cf. staudtii + + MT<br />
Ochna calod<strong>en</strong>dron r MT<br />
Ochna membranacaea + I ST<br />
Octoknema grl + r ST<br />
Octo lobus angustatus + I MT<br />
Olacaceae sp 1 +<br />
Olax gambecola r ST<br />
Olax latifolia + ST<br />
Olax mannii + ST<br />
Olax suaveol<strong>en</strong>s r ST<br />
Oldfieldia africana LT<br />
Olyra latifolia +<br />
Ongokea gore + r I LT<br />
Oricia lecontiana I + S<br />
Oricia trifoliata + MT<br />
Ormocarpum sp 1 +<br />
Oubanguia africana + I r I MT<br />
Oubanguia alata + I r MT<br />
Ouratea spec. (HNC 40350) + r S<br />
Pachypodanthum staudtii I I I + LT<br />
Panda oleosa + r + + ST<br />
Pandanus candelabrum + ST<br />
Papilionaceae sp 1 +<br />
Papilionaceae sp2 r<br />
Parinari sp 1 + r<br />
Parkia bicolor I 11 11 r I I + LT<br />
Parkia filicoidea + r LT<br />
Paullinia sapinda + WC<br />
Pausinystalia johimbe I MT<br />
P<strong>en</strong>ianthus longifolius + + S<br />
P<strong>en</strong>taclethra eetveldeana r + MT<br />
P<strong>en</strong>tadesma blltyracea r MT<br />
P<strong>en</strong>tas sp 1 11 I + 11 11 H<br />
Persea americana I + MT<br />
Petersianthlls macrocarplls r r + LT<br />
Piper 11mbellatum r + H<br />
Piptostigma preussii + r MT<br />
Plagiosiphon grl + + r LT<br />
Plagiosiphon multijugus r LT<br />
Monodora sp 1 r<br />
Mostuea brunoniste NC<br />
Mucuna flagellipes +<br />
Mussa<strong>en</strong>da sp 1 +<br />
Myrianthus serratus + + MT<br />
Napoleonaea sp 1 + ST<br />
Nauclea diderrichii + + LT<br />
Newbouldia laevis I I I 11<br />
Newtonia griffoniana + LT<br />
Nonthospondias cf. staudtii + + MT<br />
Ochna calod<strong>en</strong>dron r MT<br />
Ochna membranacaea + I ST<br />
Octoknema grl + r ST<br />
Octo lobus angustatus + I MT<br />
Olacaceae sp 1 +<br />
Olax gambecola r ST<br />
Olax latifolia + ST<br />
Olax mannii + ST<br />
Olax suaveol<strong>en</strong>s r ST<br />
Oldfieldia africana LT<br />
Olyra latifolia +<br />
Ongokea gore + r I LT<br />
Oricia lecontiana I + S<br />
Oricia trifoliata + MT<br />
Ormocarpum sp 1 +<br />
Oubanguia africana + I r I MT<br />
OUbanguia alata + I r MT<br />
Ouratea spec. (HNC 40350) + r S<br />
Pachypodanthum staudtii I I I + LT<br />
Panda oleosa + r + + ST<br />
Pandanus candelabrum + ST<br />
Papilionaceae sp 1 +<br />
Papilionaceae sp2 r<br />
Parinari sp I + r<br />
Parkia bicolor I 11 11 r I I + LT<br />
Parkia filicoidea + r LT<br />
Paullinia sapinda + WC<br />
Pausinystalia johimbe I MT<br />
P<strong>en</strong>ianthus longifolius + + S<br />
P<strong>en</strong>taclethra eetveldeana r + MT<br />
P<strong>en</strong>tadesma blltyracea r MT<br />
P<strong>en</strong>tas spI 11 I + 11 11 H<br />
Persea americana I + MT<br />
Petersianthlls macrocarplls r r + LT<br />
Piper 11mbellatum r + H<br />
Piptostigma prellssii + r MT<br />
Plagiosiphon grl + + r LT<br />
Plagiosiphon mllltijuglls r LT<br />
158<br />
158
Vegetation type la lIa lib lie llla IVa Va Growth form<br />
Vegetation type la lIa lib lie llla IVa Va Growth form<br />
Poga oleosa r LT<br />
Protomegabaria stapfiana + ST<br />
Pseudospondias cf. macrocera + + + r + LT<br />
Pseudospondias microcarpa r r + <strong>II</strong> + LT<br />
Pteleopsis hylod<strong>en</strong>dron r r + LT<br />
Ptychopetalum cf. rud<strong>en</strong>tessi + WC<br />
RhabdophylIum spI +<br />
Rinorea caudata + r r S<br />
Rinorea d<strong>en</strong>tata <strong>II</strong> 11 + I ST<br />
Rinorea exapp<strong>en</strong>diculata + + S<br />
Rinorea spI + S<br />
Rothmannia sp I<br />
Sabicea calycina +<br />
Salacia longipes + WC<br />
Salacia spI r<br />
Salacia spI <strong>II</strong> <strong>II</strong> I I +<br />
Salacia staudtiana I + + + WC<br />
Sapindaceae sp I + I + <strong>II</strong> +<br />
Sapium elIipticum + MT<br />
Sapotaceae sp I<br />
Schumanniophyton<br />
magnificum + ST<br />
Sclerosperma mannii r P<br />
Scottellia mimfi<strong>en</strong>sis r MT<br />
Scytopetalaceae sp I + ST<br />
Scytopetalum klaineanum + + MT<br />
Setaria megaphylIa I GH<br />
Sorindeia grandifolia HI <strong>II</strong> <strong>II</strong> I I MT<br />
Sorindeia juglandifolia + ST<br />
Poga oleosa r LT<br />
Protomegabaria stapfiana + ST<br />
Pseudospondias cf. macrocera + + + r + LT<br />
Pseudospondias microcarpa r r + <strong>II</strong> + LT<br />
Pteleopsis hylod<strong>en</strong>dron r r + LT<br />
Ptychopetalum cf. rud<strong>en</strong>tessi + WC<br />
Rhabdophyllum sp I +<br />
Rinorea caudata + r r S<br />
Rinorea d<strong>en</strong>tata <strong>II</strong> 11 + I ST<br />
Rinorea exapp<strong>en</strong>diculata + + S<br />
Rinorea spI + S<br />
Rothmannia sp I<br />
Sabicea calycina +<br />
Salacia longipes + WC<br />
Salacia spI r<br />
Salacia spI <strong>II</strong> <strong>II</strong> I I +<br />
Salacia staudtiana I + + + WC<br />
Sapindaceae sp I + I + <strong>II</strong> +<br />
Sapium ellipticum + MT<br />
Sapotaceae sp I<br />
Schumanniophyton<br />
magnificum + ST<br />
Sclerosperma mannii r P<br />
Scottellia mimfi<strong>en</strong>sis r MT<br />
Scytopetalaceae sp I + ST<br />
Scytopetalum klaineanum + + MT<br />
Setaria megaphylla I GH<br />
Sorindeia grandifolia HI <strong>II</strong> <strong>II</strong> I I MT<br />
Sorindeia juglandifolia + ST<br />
Soyauxia gabon<strong>en</strong>sis r MT<br />
Soyauxia talbotii + + MT<br />
Soyauxia gabon<strong>en</strong>sis r MT<br />
Soyauxia talbotii + + MT<br />
Spathodea campanulata + LT<br />
Spathodea campanulata + LT<br />
Spondias cy<strong>the</strong>rea + ST<br />
Standfieldiella imperforata +<br />
Sterculia subviolacea r I + MT<br />
Strombosia scheftleri + + MT<br />
Strombosia z<strong>en</strong>keri + ST<br />
Strophanthus gratus + r + WC<br />
Strychnos aculeata + WC<br />
Strychnos congolana + WC<br />
Strychnos eleocarpa + + r WC<br />
Strychnos phaeotricha + WC<br />
Strychnos staudtii <strong>II</strong> + r I WC<br />
Swartzia fistuloides r LT<br />
Syzygium guine<strong>en</strong>se r MT<br />
Syzygium rowlandii + MT<br />
Syzygium sp I + +<br />
Tabernaemontana pachys. + ST<br />
Spondias cy<strong>the</strong>rea + ST<br />
Standfieldiella imperforata +<br />
Sterculia subviolacea r I + MT<br />
Strombosia scheftleri + + MT<br />
Strombosia z<strong>en</strong>keri + ST<br />
Strophanthus gratus + r + WC<br />
Strychnos aculeata + WC<br />
Strychnos congolana + WC<br />
Strychnos eleocarpa + + r WC<br />
Strychnos phaeotricha + WC<br />
Strychnos staudtii <strong>II</strong> + r I WC<br />
Swartzia fistuloides r LT<br />
Syzygium guine<strong>en</strong>se r MT<br />
Syzygium rowlandii + MT<br />
Syzygium spI + +<br />
Tabernaemontana pachys. + ST<br />
159<br />
159
Vegetation type la lIa lib lie Ilia IVa Va Growth form<br />
Vegetation type la lIa lib lie Ilia IVa Va Growth form<br />
Tapura africana + + + LT<br />
Tetraplaura tetraptera + I + MT<br />
Thomandersia congolana + + + S<br />
Trachyphrynium braunianum + <strong>II</strong><br />
Treculia africana r MT<br />
Treculia spec. (HNC 30012) r<br />
Trichilia emetica + ST<br />
Trichilia rubesc<strong>en</strong>s + ST<br />
Trichilia welwitschii r I + MT<br />
Trichoscypha acuminata + + r MT<br />
Trichoscypha arborea + + r r + LT<br />
Trichoscypha ferruginia + I r + ST<br />
Turraeanthus africanus I + Il + I MT<br />
Tylophora cameroonica + NC<br />
Uapaca acuminata + + LT<br />
Uapaca staudtii + + + I MT<br />
Uapaca vanhouttei + <strong>II</strong> 1I MT<br />
Urera cameroon<strong>en</strong>sis + NC<br />
Uvariastrum pierreanum r r ST<br />
Uvariod<strong>en</strong>dron sp 1 + Il r + Il + ST<br />
Vitex ciliata + LT<br />
Vitex grandifolia Il + + I <strong>II</strong> I LT<br />
Vitex rivularis + I MT<br />
Vitis aralioides + NC<br />
Vitis quadricularia + NC<br />
Vitis spl + I + + + NC<br />
Voacanga thouarsii r ST<br />
Xylopia parviflora r r + MT<br />
Zanthoxylum heitzii r + 11 + LT<br />
Zanthoxylum tessmannii + r I LT<br />
Zingiber <strong>of</strong>ficinale + H<br />
Zingiberaceae sp 1 + H<br />
Tapura africana + + + LT<br />
Tetraplaura tetraptera + I + MT<br />
Thomandersia congolana + + I + S<br />
Trachyphrynium braunianum + I <strong>II</strong><br />
Treculia africana r MT<br />
Treculia spec. (HNC 30012) r<br />
Trichilia emetica + ST<br />
Trichilia rubesc<strong>en</strong>s + ST<br />
Trichilia welwitschii r I + MT<br />
Trichoscypha acuminata + + r MT<br />
Trichoscypha arborea + + r r + LT<br />
Trichoscypha ferruginia + I r + ST<br />
Turraeanthus africanus I + <strong>II</strong> + I MT<br />
Tylophora cameroonica + NC<br />
Uapaca acuminata + + LT<br />
Uapaca staudtii + + + I MT<br />
Uapaca vanhouttei + 1I <strong>II</strong> MT<br />
Urera cameroon<strong>en</strong>sis + NC<br />
Uvariastrum pierreanum r r ST<br />
Uvariod<strong>en</strong>dron sp 1 + <strong>II</strong> r + 1I + ST<br />
Vitex ciliata + LT<br />
Vitex grandifolia <strong>II</strong> + + I <strong>II</strong> I LT<br />
Vitex rivularis + I MT<br />
Vitis aralioides + NC<br />
Vitis quadricularia + NC<br />
Vitis spl + I + + + NC<br />
Voacanga thouarsii r ST<br />
Xylopia parviflora r r + MT<br />
Zanthoxylum heitzii r + <strong>II</strong> + LT<br />
Zanthoxylum tessmannii + r I LT<br />
Zingiber <strong>of</strong>ficinale + H<br />
Zingiberaceae se 1 + H<br />
160<br />
160
ANNEX VI List <strong>of</strong> bird species observed in <strong>the</strong> TCP research area<br />
ANNEX VI List <strong>of</strong> bird species observed in <strong>the</strong> TCP research area<br />
The listed species were recorded in <strong>the</strong> period May 1995 to November 1997. As no systematic bird<br />
survey has started yet, <strong>the</strong> list is a mere compilation <strong>of</strong> <strong>the</strong> species lists <strong>of</strong> Jan Jans<strong>en</strong> (WAU),<br />
Patrick Hommel (SC-DLO; 1995; 1996), Thorn Kuyper (WAU) and Bar<strong>en</strong>d van Gemerd<strong>en</strong>.<br />
Nom<strong>en</strong>clature follows Serle & Morel (1997).<br />
The listed species were recorded in <strong>the</strong> period May 1995 to November 1997. As no systematic bird<br />
survey has started yet, <strong>the</strong> list is a mere compilation <strong>of</strong> <strong>the</strong> species lists <strong>of</strong> Jan Jans<strong>en</strong> (WAU),<br />
Patrick Hommel (SC-DLO; 1995; 1996), Thorn Kuyper (WAU) and Bar<strong>en</strong>d van Gemerd<strong>en</strong>.<br />
Nom<strong>en</strong>clature follows Serle & Morel (1997).<br />
Accipitridae<br />
Accipitridae<br />
Accipiter touss<strong>en</strong>elii<br />
Dryotriorchis spectabilis<br />
Gyphohierax angol<strong>en</strong>sis<br />
Kaupifalco monogrammicus<br />
Macheirhamphus alcinus<br />
Milvus migrans<br />
Polyboroides radiatus<br />
Urotriorchis macrourus<br />
Circaetus gallicus?'<br />
Stephanoaetus coronatus?'<br />
Accipiter touss<strong>en</strong>elii<br />
Dryotriorchis spectabilis<br />
Gyphohierax angol<strong>en</strong>sis<br />
Kaupifalco monogrammicus<br />
Macheirhamphus alcinus<br />
Milvus migrans<br />
Polyboroides radiatus<br />
Urotriorchis macrourus<br />
Circaetus gallicus?'<br />
Stephanoaetus coronatus?'<br />
Alcedinidae<br />
Alcedinidae<br />
Alcedo quadribrachys<br />
Ceyxpicta<br />
Halycon badia<br />
Halycon s<strong>en</strong>egal<strong>en</strong>sis<br />
Alcedo quadribrachys<br />
Ceyxpicta<br />
Halycon badia<br />
Halycon s<strong>en</strong>egal<strong>en</strong>sis<br />
Apodidae<br />
Apodidae<br />
Apus apus<br />
Apus apus<br />
Ardeidae<br />
Ardeidae<br />
Ardeola ibis<br />
Ardeola ibis<br />
Bucerotidae<br />
Bucerotidae<br />
Bycanistes cylindric us cylindricus<br />
Bycanistes fistulator<br />
Bycanistes subcylindricus<br />
Ceratogymna atrata<br />
Tockus camurus<br />
Tockus Jasciatus semifasciatus<br />
Bycanistes cylindricus cylindricus<br />
Bycanistes jistulator<br />
Bycanistes subcylindricus<br />
Ceratogymna atrata<br />
Tockus camurus<br />
Tockus fasciatus semifasciatus<br />
Capitonidae<br />
Capitonidae<br />
Buccanodon duchaillui<br />
Gymnobucco bonapartei<br />
Pogoniulus atrojlavus<br />
Pogoniulus bilineatus<br />
Trachyphonus pupuratus<br />
Buccanodon duchaillui<br />
Gymnobucco bonapartei<br />
Pogoniulus atrojlavus<br />
Pogoniulus bilineatus<br />
Trachyphonus pupuratus<br />
I (?) Id<strong>en</strong>tification uncertain<br />
(?) Id<strong>en</strong>tification uncertain<br />
161<br />
161<br />
West african goshawk<br />
Congo Serp<strong>en</strong>t-eagle<br />
Palm-nut vulture<br />
Lizard buzzard<br />
Bathawk<br />
Black kite<br />
Harrier hawk<br />
Long-tailed hawk<br />
Short-toed eagle<br />
Crowned hawk-eagle<br />
West african goshawk<br />
Congo Serp<strong>en</strong>t-eagle<br />
Palm-nut vulture<br />
Lizard buzzard<br />
Bathawk<br />
Black kite<br />
Harrier hawk<br />
Long-tailed hawk<br />
Short-toed eagle<br />
Crowned hawk-eagle<br />
Shining-blue kingfisher<br />
Pygmy kingfisher<br />
Chocolate-backed kingfisher<br />
S<strong>en</strong>egal kingfisher<br />
Shining-blue kingfisher<br />
Pygmy kingfisher<br />
Chocolate-backed kingfisher<br />
S<strong>en</strong>egal kingfisher<br />
European swift<br />
European swift<br />
Cattle egret<br />
Cattle egret<br />
Brown-cheeked hornbill<br />
Piping hornbill<br />
Black-and-white-casqued hornbill<br />
Black-casqued hornbill<br />
Red-billed dwarf hornbill<br />
Black-and-white-tailed hornbill<br />
Brown-cheeked hornbill<br />
Piping hornbill<br />
Black-and-white-casqued hornbill<br />
Black-casqued hornbill<br />
Red-billed dwarf hornbill<br />
Black-and-white-tailed hornbill<br />
Duchaillu's yellow-spotted barbet<br />
Grey-throated barbet<br />
Red-rumped tinker-bird<br />
Lemon-rumped tinker-bird<br />
Yellow-billed barbet<br />
Duchaillu's yellow-spotted barbet<br />
Grey-throated barbet<br />
Red-rumped tinker-bird<br />
Lemon-rumped tinker-bird<br />
Yellow-billed barb et
Columbidae<br />
Columbidae<br />
Treron australis<br />
Turtur aJer<br />
Turtur brehmeri<br />
Turtur tympanistria<br />
Treron australis<br />
Turtur aJer<br />
Turtur brehmeri<br />
Turtur tympanistria<br />
Coraciidae<br />
Coraciidae<br />
Eurostomus gular is<br />
Eurostomus gular is<br />
Corvidae<br />
Corvidae<br />
Corvus albus<br />
Corvus albus<br />
Cuculidae<br />
Cuculidae<br />
Ceuthmochares aereus<br />
Chrysococcyx cupreus<br />
Cuculus solitarius<br />
Ceuthmochares aereus<br />
Chrysococcyx cupreus<br />
Cuculus solitarius<br />
Dicruridae<br />
Dicruridae<br />
Dicrurus adsimilis<br />
Dicrurus adsimilis<br />
Estrildidae<br />
Estrildidae<br />
Estrilda melpoda<br />
Estrilda nonnula<br />
Lonchura bicolor<br />
Nigrita canicapilla<br />
Nigrita Jusconota<br />
Spermophaga haematin a<br />
Estrilda melpoda<br />
Estrilda nonnula<br />
Lonchura bicolor<br />
Nigrita canicapilla<br />
Nigrita Jusconota<br />
Spermophaga haematin a<br />
Hirundinidae<br />
Hirundinidae<br />
Hirundo nigrita<br />
Hirundo rustica<br />
Psalidoprocne pristoptera<br />
Riparia paludicola<br />
Hirundo nigrita<br />
Hirundo rustica<br />
Psalidoprocne pristoptera<br />
Riparia paludicola<br />
Meropidae<br />
Meropidae<br />
Merops albicollis<br />
Merops albicoWs<br />
Monatchidae<br />
Monatchidae<br />
Terpsiphone rufiv<strong>en</strong>ter neumanni<br />
Terpsiphone viridis<br />
Terpsiphone rufiv<strong>en</strong>ter neumanni<br />
Terpsiphone viridis<br />
Motacillidae<br />
Motacillidae<br />
Motacilla aguimp<br />
Motacilla aguimp<br />
Muscicapidae<br />
Muscicapidae<br />
Artomyias fuliginosa<br />
Erythrocerus mccali<br />
Muscicapa striata<br />
Platysteira castanea<br />
Platysteira tonsa<br />
Artomyias juliginosa<br />
Erythrocerus mccali<br />
Muscicapa striata<br />
Platysteira castanea<br />
Platysteira tonsa<br />
162<br />
162<br />
Gre<strong>en</strong> fruit-pigeon<br />
Red-billed wood dove<br />
Blue-headed dove<br />
Tambourine dove<br />
Gre<strong>en</strong> fruit-pigeon<br />
Red-billed wood dove<br />
Blue-headed dove<br />
Tambourine dove<br />
Broad-billed roller<br />
Broad-billed roller<br />
Pied crow<br />
Pied crow<br />
Yellowbill coucal<br />
Emerald cuckoo<br />
Red-chested cuckoo<br />
Yellowbill coucal<br />
Emerald cuckoo<br />
Red-chested cuckoo<br />
Glossy-backed drongo<br />
Glossy-backed drongo<br />
Orange-cheeked waxbill<br />
Black-crowned waxbill<br />
Black-and-white mannikin<br />
Grey-crowned negro-finch<br />
White-breasted negro-finch<br />
Blue-billed weaver<br />
Orange-cheeked waxbill<br />
Black-crowned waxbill<br />
Black-and-white mannikin<br />
Grey-crowned negro-finch<br />
White-breasted negro-finch<br />
Blue-billed weaver<br />
White-throated blue swallow<br />
European swallow<br />
Black saw-wing<br />
African sand martin<br />
White-throated blue swallow<br />
European swallow<br />
Black saw-wing<br />
African sand martin<br />
White-throated bee-eater<br />
White-throated bee-eater<br />
Red-bellied paradise-flycatcher<br />
African paradise-flycatcher<br />
Red-bellied paradise-flycatcher<br />
African paradise-flycatcher<br />
African pied wagtail<br />
African pied wagtail<br />
Dusky flycatcher<br />
Chestnut-capped flycathcer<br />
Cassin's grey flycatcher<br />
Chestnut wattle-eye<br />
White-spotted wattle-eye<br />
Dusky flycatcher<br />
Chestnut-capped flycathcer<br />
Cassin's grey flycatcher<br />
Chestnut wattle-eye<br />
White-spotted wattle-eye
Musophagidae<br />
Musophagidae<br />
Corythaeola cristata<br />
Tauraco persa<br />
Corythaeola cristata<br />
Tauraco persa<br />
N ectariniidae<br />
N ectariniidae<br />
Anthreptes gabonicus<br />
Nectarinia chloropygia<br />
Nectarinia olivaceae<br />
Nectarinia superba<br />
Anthreptes gabonicus<br />
Nectarinia chloropygia<br />
Nectarinia olivaceae<br />
Nectarinia superba<br />
Oriolidae<br />
Oriolidae<br />
Griolus brachyrhynchus<br />
Griolus brachyrhynchus<br />
Phasianidae<br />
Phasianidae<br />
Francolinus lathami<br />
Francolinus squamatus<br />
Francolinus lathami<br />
Francolinus squamatus<br />
Picidae<br />
Picidae<br />
Campe<strong>the</strong>ra caillautii<br />
Campe<strong>the</strong>ra nivosa<br />
D<strong>en</strong>dropicos gabon<strong>en</strong>sis<br />
Mesopicos xantholophus<br />
Verreauxia ajricana<br />
Campe<strong>the</strong>ra caillautii<br />
Campe<strong>the</strong>ra nivosa<br />
D<strong>en</strong>dropicos gabon<strong>en</strong>sis<br />
Mesopicos xantholophus<br />
Verreauxia ajricana<br />
Ploceidae<br />
Ploceidae<br />
Malimbus nit<strong>en</strong>s<br />
Malimbus rubicollis<br />
Malimbus scutatus<br />
Pir<strong>en</strong>estes ostrinus<br />
Ploceus cucullatus<br />
Malimbus nit<strong>en</strong>s<br />
Malimbus rubicollis<br />
Malimbus scutatus<br />
Pir<strong>en</strong>estes ostrinus<br />
Ploceus cucullatus<br />
Psittacidae<br />
Psittacidae<br />
Psittacus erythacus<br />
Psittacus erythacus<br />
Pycnonotidae<br />
Pycnonotidae<br />
Andropadus vir<strong>en</strong>s<br />
Baeopopgon indicator<br />
Chlorocichla simplex<br />
Cringiger calurus<br />
Ixonotus guttatus<br />
Nicator chloris<br />
Phyllastrephus icterinus<br />
Pycnonotus barbatus<br />
Thescelocichla leucopleurus<br />
Andropadus vir<strong>en</strong>s<br />
Baeopopgon indicator<br />
Chlorocichla simplex<br />
Cringiger calurus<br />
Ixonotus guttatus<br />
Nicator chloris<br />
Phyllastrephus icterinus<br />
Pycnonotus barbatus<br />
Thescelocichla leucopleurus<br />
Strigidae<br />
Strigidae<br />
Ciccaba woodfordi<br />
Ciccaba woodfordi<br />
Sturnidae<br />
Sturnidae<br />
Lamprotornis spl<strong>en</strong>didus<br />
Peoptera lugubris<br />
Lamprotornis spl<strong>en</strong>didus<br />
Peoptera lugubris<br />
163<br />
163<br />
Blue plantain-eater<br />
Gre<strong>en</strong>-crested touraco<br />
Blue plantain-eater<br />
Gre<strong>en</strong>-crested touraco<br />
Mouse-brown sunbird<br />
Olive-bellied sunbird<br />
Olive sunbird<br />
Superb sunbird<br />
Mouse-brown sunbird<br />
Olive-bellied sunbird<br />
Olive sunbird<br />
Superb sunbird<br />
Black-headed oriole<br />
Black-headed oriole<br />
Latham's francolin<br />
Scaly francolin<br />
Latham's francolin<br />
Scaly francolin<br />
Gre<strong>en</strong>-backed woodpecker<br />
Buff-spotted woodpecker<br />
Gaboon woodpecker<br />
Gold<strong>en</strong>-crowned woodpecker<br />
Pigmy woodpecker<br />
Gre<strong>en</strong>-backed woodpecker<br />
Buff-spotted woodpecker<br />
Gaboon woodpecker<br />
Gold<strong>en</strong>-crowned woodpecker<br />
Pigmy woodpecker<br />
Blue-billed malimbe<br />
Red-headed malimbe<br />
Red-v<strong>en</strong>ted malimbe<br />
Seed-cracker<br />
Village weaver<br />
Blue-billed malimbe<br />
Red-headed malimbe<br />
Red-v<strong>en</strong>ted malimbe<br />
Seed-cracker<br />
Village weaver<br />
Grey parrot<br />
Grey parrot<br />
Little gre<strong>en</strong>bul<br />
Honey guide gre<strong>en</strong>bul<br />
Simple leaf-love<br />
White-bearded bulbul<br />
Spotted bulbul<br />
West african nicitator<br />
Lesser icterine gre<strong>en</strong>bul<br />
Common gard<strong>en</strong> bulbul<br />
Swamp bulbul<br />
Little gre<strong>en</strong>bul<br />
Honey guide gre<strong>en</strong>bul<br />
Simple leaf-love<br />
White-bearded bulbul<br />
Spotted bulbul<br />
West african nicitator<br />
Lesser icterine gre<strong>en</strong>bul<br />
Common gard<strong>en</strong> bulbul<br />
Swamp bulbul<br />
West African wood-owl<br />
West African wood-owl<br />
Spl<strong>en</strong>did glossy starling<br />
Narrow-tailed starling<br />
Spl<strong>en</strong>did glossy starling<br />
Narrow-tailed starling
Sylviidae<br />
Sylviidae<br />
Bathmocercus rufus<br />
Hylia prasina<br />
Prinia bairdii<br />
Sylvietta vir<strong>en</strong>s<br />
Bathmocercus rufus<br />
Hylia prasina<br />
Prinia bairdii<br />
Sylvietta vir<strong>en</strong>s<br />
Turdidae<br />
Turdidae<br />
Ale<strong>the</strong> diademata<br />
Cossypha niveicapilla<br />
Stiphrornis erythrothorax<br />
Ale<strong>the</strong> diademata<br />
Cossypha niveicapilla<br />
Stiphrornis erythrothorax<br />
Zosteropidae<br />
Zosteropidae<br />
Zosterops s<strong>en</strong>egal<strong>en</strong>sis<br />
Zosterops s<strong>en</strong>egal<strong>en</strong>sis<br />
164<br />
164<br />
Black-faced rufous warbler<br />
Gre<strong>en</strong> hyla<br />
Banded prinia<br />
Gre<strong>en</strong> crombec<br />
Black-faced rufous warbler<br />
Gre<strong>en</strong> hyla<br />
Banded prinia<br />
Gre<strong>en</strong> crombec<br />
Fire-crest ale<strong>the</strong><br />
Snowy-crowned robin-chat<br />
Forest robin<br />
Fire-crest ale<strong>the</strong><br />
Snowy-crowned robin-chat<br />
Forest robin<br />
Yellow white-eye<br />
Yellow white-eye