Botanical Survey
of
Tchabal Mbabo, Adamawa Province
Cameroon
For:
Transboundary Collaboration for Ecosystem Conservation: the Mountain
Forests of Gashaka-Gumti National Park, Nigeria and Tchabal Mbabo,
Cameroon; project number RAF/G43/A/1G/31.
Report compiled by Hazel Chapman
Nigerian Montane Forest Project
University of Canterbury
2004
Report layout by Matt Walters
University of Canterbury, NZ
2004
Table of Contents
Sketch map
Executive summary
Terms of reference
Personnel
Itinerary
Methods
Literature review
Vegetation units and preliminary inventory for key plant species
2
3
4
4
5
6
7
10
Overgrazed Sporolobus africanus grassland
Hyparrhenia grassland
Water seepages/bogs
Montane escarpment forest
Submontane forest
Hyparrhenia savanna > 1500
Hyparrhenia savanna < 1500
Woody savanna/ transition forest
Savanna
Lowland Savanna
Montane gallery forests
Submontane gallery forests
Lowland gallery forests
Afromomum swamp forest
Montane forest – grassland ecotone
Cultivated flood plains with Pennisetum purpureum
11
11
11
13
13
13
15
15
15
17
17
19
19
19
21
21
Comparisons with previous surveys
Priority localities for biodiversity conservation
Threats to biodiversity
Recommendations for conservation and management
References
Appendix 1
Appendix 2
Appendix 3
Appendix 4
23
25
28
29
30
31
32
32
33
Figure 1
Sketch map of Tchabal Mbabo showing the locations referred to in the text.
DODEO
NDONGAWA
FUNGOI
DADAWAL
YANGARE
MAYO
KELELE
WOGOMDOU
SAMBO LABO
TCHABAL MBABO
CAMEROON
Elevations
> 2400 m
> 2000 m
> 1600 m
> 1200 m
20 km
DRAWN WALTERS 2004 AFTER THOMAS 1996
2
Executive Summary
Vegetation units
Sixteen vegetation units were identified during the survey, and twelve of these were of sufficient
area to include on the preliminary vegetation map:
1.
Overgrazed Sporolobus africanus grassland
2.
Montane Hyparrhenia grassland*
3.
Water seepages/bogs*
4.
Montane escarpment forest
5.
Submontane forest
6.
Hyparrhenia savanna > 1500
7.
Hyparrhenia savanna < 1500
8.
Woody savanna/ transition forest
9.
Savanna
10.
Lowland savanna
11.
Montane gallery forest
12.
Submontane gallery forest
13.
Lowland gallery forest
14.
Afromomum swamp forest*
15.
Montane forest – grassland ecotone
16.
Cultivated flood plains with Pennisetum purpureum*
* Present but not mapped.
Globally significant botanical diversity
The montane and submontane forests of Tchabal Mbabo and Gashaka Gumti National Park
(GGNP) are globally important because they are satellite populations of many Afromontane
endemics, and are of a rare dry type. This survey identified ten IUCN globally threatened
montane plant species on Tchabal Mbabo, and there are undoubtedly more. Locally these
forests are crucial for maintaining a year round water supply for local communities and are
the headwaters of several major rivers. They are also habitat for wildlife. Together the montane
forests of Tchabal Mbabo and GGNP provide a good representation of West African montane
vegetation to 2400 m in elevation. Moreover the natural transition of savanna through
submontane to montane forest is rarely found in West Africa. Despite being geographically
close and geologically similar, the upland forests of Tchabal Mbabo and GGNP are subtly
different in their floristic composition, presumably reflecting historical differences. This is
evident in the fact that Gashaka Gumti forests are home to chimpanzee and other frugiverous
primates which are absent on Tchabal Mbabo.
The savanna and gallery forest below +/- 1500 m are not especially significant for their species
composit ion, but becom e so in the context of a whole mountain ecosystem.
Threats
Threats to the vegetation of Tchabal Mbabo come from the local Fulbe in terms of overgrazing
by cattle, burning and wood collection. Contractors from Bamenda are organizing the
unsustainable harvest of Prunus africana.
Recommendations
Recommendations for conservation and management support the idea of creating a National
Park incorporating the whole of Tchabal Mbabo with different management zones:
1)
total protection (escarpment forests, and some areas of the plateau with representative
types of stream fringing forest).
2)
rural development on the plateau with the introduction of alternative grazing and wood
sources. Eucalyptus species have proved very effective on neighboring Mambilla Plateau
in Nigeria, but fast growing native species such as Croton macrostachyus and Hallea stipulosa
could be trialed.
3)
rural development on the Dodeo plain with a wide buffer zone between it and the
bottom of the escarpment.
3
Terms of Reference
Objectives
To produce an inventory of the actual vegetation in the Tchabal Mbabo area, taking
into account differentiation according to habitat. The focus of the survey was on the
key species (abundance, spatial distribution and value) that support the global importance
of conservation of Tchabal Mbabo. Special attention was paid to the state of the montane
forests and the transition towards wooded savannahs and the spatial distribution of
these habitats, in order to support the creation of a transboundary conservation area.
Activities
1.
2.
3.
4.
5.
6.
A review of the results of previous vegetation surveys and studies at Gashaka GumtiTchabal Mbabo.
A survey of some poorly known sites within the defined project area of Tchabal Mbabo.
The development of a preliminary inventory for key plant species and the characterization
of vegetation units of the draft vegetation map in close collaboration with Gideon Shu.
The identification of priority localities for biodiversity conservation (zones of
high/medium/low biodiversity interest) from a botanical point of view.
Information on threats to biodiversity at these and other sites.
A series of recommendations based on biodiversity factors for conservation and
management.
Outputs
1.
The floristic characterization of main units distinguished on the draft vegetation map
(developed on the basis of Landsat ETM + imagery by the GIS consultant).
2.
A report on the globally significant botanical biodiversity of the project area.
Personnel
Dr Hazel Chapman, Botanist, University
of Canterbury, New Zealand
Mr Markson Markus, Botanical Assistant,
Nigerian Conservation Foundation,
Gashaka, Nigeria.
Mr Gideon Shu, GIS specialist, Douala,
Cameroon.
Markson Markus and Gideon Shu
consulting the GPS in savanna below
Fungoi.
4
Itinerary
January 2004
W 07 Arrived in Sambolabo from Banyo.
T
08
Drove from Sambolabo to Mayo Kelele and on to the Prunus camp. Trekked on
to the Yangaré camp (2025 m elevation). Spent the afternoon studying the stream
fringing forest fragments and collecting specimens.
F
09
Descended into and studied the Prunus forest on the escarpment edge, due north
of Yangaré camp at 2166 m; N 07.24061; E 012.14579. Descended approximately
400 m into the forest. Collected specimens and studied the species composition.
Could not go further as our guide was unhappy with the terrain.
S
10
From the Yangaré camp walked East along the escarpment edge to where we could
descend a steep bluff which allowed us to study ungrazed grassland and forest edge
communities. Descended from 2223 m – 2117 m; N 07o14’46.0”; E 012o 09’00.4”.
Collected and took photographs. Returned to camp via a seepage area where we
collected.
S
11
Trekked from Yangaré camp to Tchabal Mbabo village where we were reunited
with Gideon Shu and the other members of the biodiversity survey team. Collected
en route. Camped by a swamp forest fragment, full of Afromomum sp: at 1710 m;
N 07o 15’16.2”; E 012o 15’19.1”. Met with the Ardo of Tchabal Mbabo and received
a warm welcome.
M
12
Walked to Ndongawa camp in a transition between grassland and forest: 1924 m;
N 07o18’ 59.9”; E 012o12’47.8”. Spent the afternoon drying and identifying specimens.
T
13
Stayed at Ndongawa studying and collecting in a nearby gallery forest. Entered at
1923 m; N 07o 18’57.8”; E 012o12’48.0”. Here we used a local guide, Abubakkar,
from the nearby Fulbe camp.
W
14
Spent the morning studying another nearby gallery forest at +/- 1810 m; N
07o 18’53.4”; E 012o12’38.4” and the surrounding little grazed Hyparrhenia savanna.
This was followed by a long walk down to a camp site at the confluence of the
Mayo Ledi and Mayo Barka at 718 m; N07o22’21.2”; E012o 07’01.0”. During this
walk we passed interesting gallery forest that warrants further study.
T
15
Examined the gallery forest and savanna at +/- 700 m and then trekked on to Dodeo
village and our camp site by the Mayo Deo at 637 m. Approximately 6 hours
walking.
S
17
Trekked from the Mayo Selbe camp to Fungoi: 2059 m; N 07o15’08.3”; E 012o03’35.3”.
As this was a 9 hour walk we could only observe the vegetation types we passed
through, but they were woody savanna with gallery forest, montane forest fragments
and overgrazed Sporobolus grassland. The gallery forest between 1200 m – 1500
m needs study.
S
18
Spent the morning drying and identifying specimens. In the afternoon studied the
forest fragments round Fungoi and walked over to the escarpment edge to look
into the forest far below.
M
19
Changed all the botanical specimens and wrote up notes in the morning. Trekked
to Mayo Kelele in the afternoon, collecting at a water seepage spot en route.
T
20
Trekked down to Sambolabo where we met up with Dennis Anyi and took bikes
out to Banyo.
5
Methods
Study area
The botanical survey was undertaken by trekking round Tchabal Mbabo from Mayo Kelelé via
Yangaré, Tchabal Mbabo village, Dodeo and Fungoi (Fig. 1), studying the vegetation types and
collecting botanical specimens as we went.
Particular emphasis was placed on the montane ecosystem because this is the most botanically
rare and interesting vegetation type on Tchabal Mbabo.
Ground-truthing
Throughout the study we conferred with Gideon Shu in order to ground-proof (interpret and
corroborate) his GIS land cover map.
GPS
Wherever conditions allowed a global positioning system was used to locate the position (to
within 20 meters) of studied vegetation sites and specimens collected. Forest canopy prevented
accurate use of the GPS.
Botanical collections
Eighty five botanical specimens of both fertile and sterile material that we were unable to
identify in the field were collected for identification at the Royal Botanical Gardens, Kew. The
specimens were pressed on site, and the paper changed each evening.
Photographs
Three hundred photographic slides were taken of Tchabal Mbabo during the study. These are
available on request.
Nomenclature
Plant species nomenclature follows that of Lebrun and Stork (1991-1997).
6
Literature Review
A review of the results of previous vegetation surveys
of Gashaka Gumti-Tchabal Mbabo
Gashaka Gumti
The Nigerian side of the project boundary area is almost all within Gashaka Gumti National
Park and includes the Gotel Mountains (Cabbal Waddi and Gangirwal) and undulating uplands
running between Gangirwal to Cabbal Delam and Filinga (Fig 1). The area is altitudinally,
geologically and scenically very reminiscent of neighboring Tchabal Mbabo, which is located
approximately 40 km NNE (Fig 1).
The first published account of the Gotel Mountains was by Tuley and Jackson (1971), who
visited the area in the dry season of 1969. Their collections were mainly herbaceous and
included two new species to science, an Eriocaulon (sp. nr. pulchellum) and a Bidens sp. Fifty nine
of their collections, mostly herbs, were new to Nigeria. The following year a botanical expedition
from Ife University visited the area, again concentrating on the herbaceous flora (Hall, 1970).
The first forest study of the Gotel Mountains was by J.D. Chapman between 1974 and 1975
(Chapman and Chapman, 2001). His account is based on detailed analysis of profile strips and
the collection of over 3000 herbarium specimens. It describes forest structure, species
composition and physiognomy from sub-montane (1400 m) to montane (2000 m), and describes
the montane grassland.
Chapman describes five forest types in detail, named after their dominant species:
1.
Albizia gummifera – Nuxia congesta forest at 1830 m in elevation
2.
Pouteria altissima forest at 1830 m in elevation
3.
Prunus africana - Syzygium guineense subsp. bamendae- Podocarpus latifolius forest
at 2090 m in elevation
4.
Syzygium guineense subsp. bamendae stream source forest at 2130 m in elevation
5.
Montane forest and outliers above 2290 m
At this altitude the forest edge communities typically comprised Hypericum species with some
Agarista salicifolia, Adenocarpus mannii and Gnidia glauca.
The montane grassland was rich in fire-sensitive grasses and herbs, several of which IUCN
recognise as being globally threatened.
Leinde Fadalie forest at 1700 m is more species rich than the above, including the canopy trees
Entandrophragma angolense, Pterygota mildbraedii, Anthonotha noldeae and Cordia millenii.
Twenty four IUCN Red Data List species were recorded from the Nigerian side of the boundary
(Chapman and Chapman, 2001), and there are likely several more, as over three hundred of
the more unusual specimens sent to Kew have yet to be identified.
A later expedition to the area was made by Dowsett- Lemaire (1989). Her description is based
on a few days’ observations and on the (then) unpublished accounts by J. D. Chapman. They
are especially valuable in setting the forests in a phytogeographical context, and emphasize the
high proportion of Afromontane endemics or near endemics but the paucity of local endemics
in the Nigerian montane forests.
7
In 2002 a team from the University of Canterbury, New Zealand, visited the whole of the
boundary area between Njerwai and Filinga, collecting botanical specimens as they went
(Chapman et al. 2004). This was the first botanical exploration of the northern part of the
Gotel Mountains and beyond, and highlighted the need for further, more detailed botanical
work. This expedition discovered a new species of shrub belonging to the genus Metarungia,
Family Acanthaceae, in Leinde Fadalie forest.
Tchabal Mbabo
The vegetation of Tchabal Mbabo was first mapped by Letouzey (1985) as part of a national
inventory and vegetation map. The map was based primarily on aerial photos and comparison
with other parts of the Adamaoua region. In 1996 Duncan and Jane Thomas carried out a
botanical survey of part of Tchabal Mbabo to ground-truth Letuzey’s map and classify the
vegetation types for conservation purposes. In this context they found it necessary to make
large alterations to Letouzey’s work (Thomas and Thomas, 1996).
The Thomas team spent eight days in the Sambolabo / Mayo Kelele / Fungoi area and a further
two days in the Hossere Bong Bong / Mayo Baleo (north extension of Tachabal Mbabo) areas.
They collected 198 botanical specimens during this trip, mainly from montane forest vegetation.
Based on the results of this field survey Thomas and Thomas revised Letouzey’s (1985) map
and simplified it to identify two elevational zones: a higher zone of montane / submontane
forest, scrub and grassland at or above 1700 m, and a lower zone of Sudanian wooded savanna
with gallery forests (Table 1). They found that elevation was the most important correlate
with vegetation.
The Thomas and Thomas (1996) report highlights the fact that the main botanical interest of
Tchabal Mbabo is in the presence of well developed montane forest, a vegetation type rare
in western Africa, and in the natural transition from montane forest to savanna/gallery forest,
an ecological transition that is seldom seen in western Africa. They suggest that Tchabal Mbabo
may be the best example of this transition in the area.
Further botanical work on the Tchabal Mbabo area was published in 2000 as part of a larger
remit from WWF identifying vegetation zones over Tchabal Mbabo, Tchabal Gandaba and
Vallée du Mbéré to contribute towards the creation of a conservation area in the highland
ecoregion (Grégoire 2000). It does not add botanical information relevant to this survey.
8
Table 1
(From Thomas and Thomas 1996)
Reclassification of the vegetation of the Tchabal Mbabo area. The main units of classification fall into
two groups -- montane above 1700 m and savanna below 1700 m, which is probably best described as
a mid-Sudanian savanna with Guineo-Congolian galleries.
Veg. belt by
elevation
Mapped vegetation
type(s)
Included vegetation
types
Montane belt
(above 1700)
Montane prairie
Montane galleries
Saxicolous
Cultivation
Montane forest/scrub
Grassy ridge tops
Saxicolous
Submontane savanna
(1200-1700)
Savanna +/- wooded
Gallery forest
Cultivation
High savanna
(800-1200)
Savanna woodland
Gallery forest
Cultivation/fallow
Mid-elev. savanna
(500-800)
Savanna woodland
Gallery forest
Other riparian
Fallows
Cultivation
9
Vegetation units and preliminary inventory
for key plant species
The results of our 2004 survey are in general agreement with Thomas and Thomas (1996) as
to the distribution of vegetation types and in stressing the high scientific / conservation value
of the montane and sub montane forest elements.
We agree that elevation plays a major role in determining plant species composition, but also
emphasise the role of fire and cattle grazing. Combining all factors we have recognized twelve
vegetation units of sufficient area to include on the vegetation map (Tables 2 and 3). Table 3
highlights the similarities in interpretation between Thomas and Thomas (1996) and this report,
but also illustrates differences in detail; for example while Thomas and Thomas (1996) talk
about a montane belt above 1700 m, within this belt we distinguish montane gallery forest
above 2000 m. Thomas and Thomas (1996) define the lower altitude of ‘montane prairie’ as
1700 m elevation, while in this report it’s equivalent ‘Overgrazed Sporolobus africanus grassland’
is mapped with a lower limit of 1500 m. Discrepancies such as these are explained by the fact
that the two surveys did not always overlap in locations visited. Our later survey therefore
compliments and adds to the very astute observations of Thomas and Thomas (1996).
Table 2
Vegetation units and (mapping units) of the Tchabal Mbabo area based on a combination
of Landsat ETM (Gideon Shu 2004) and ground truthing.
Vegetation Units and (Mapping Units)
Altitude (m)
A. Grassland
1
2
3
(A1) Overgrazed Sporolobus africanus grassland
Montane Hyparrhenia grassland*
Water seepages / bogs*
> 1500
> 1700
> 1500
B. Montane / submontane Forest
4
5
(B1) Montane escarpment forest
(B2) Submontane forest
> 1700
1700 – 1500
C. Savanna
6
7
8
9
10
(C1)
(C2)
(C3)
(C4)
(C5)
Hyparrhenia savanna
Hyparrhenia savanna
Woody savanna/ transition forest
Savanna
Lowland savanna
> 1500
1500 – 700
1500 – 1000
1000-700
< 700
D. Gallery Forest
11
12
13
14
(D1) Montane gallery forest
(D2) Submontane gallery forest
(D3) Lowland gallery forest
Afromomum swamp forest*
> 1800
1800 – 1500
< 1500
> 2000
E. Ecotone
15 (E1) Montane forest – grassland ecotone
>1700
F. River flats
16
C ult ivated flood plains with Pennisetum purpureum*
< 700
Within several of these basic vegetation units are variations depending on local biotic and /or
abiotic conditions. *Vegetation units 2, 3, 14 and 16 occur on too small a scale to include on
the vegetation map.
10
Vegetation unit 1
Overgrazed Sporobolus africanus grassland (Plate 1 )
Overgrazed and frequently burned Sporobolus africanus grassland is the most common vegetation
type on the rolling hills of Tchabal Mbabo plateau above +/- 1500 m. Others grasses include
the introduced Kikuyu grass, Pennisetum clandestinum which is most successful round cattle
camps, Hyparrhenia rufa and Melinis minutiflora. Shrubby Solanum indicum is widespread, and
often associated with cattle camps, as is the thorny Solanum aculeastrum. Sparsely scattered
small trees include Croton macrostachyus, Syzygium guineense subsp. guineense, Bridelia speciosa,
Trema orientalis, Ficus species and Sesbania macrantha. Many herbs survive in the grassland, most
of them widespread and common, for example Coreopsis sp., Echinops longifolia, Geranium
arabicum, Kalanchoe crenata, Veronica abyssinica, and Wahlenbergia sp. The Threatened Helichrysum
cameroonense was locally common in the grassland near to the Yangaré camp site.
Between Yangaré and Tchabal Mbabo village at +/- 2300 m elevation was a thick stand of the fire
sensitive shrubs Erica manneii and Adenocarpus mannii. The only Eucalyptus seen was close to Tchabal
Mbabo village wh er e th er e are some individual tr ees and some small plots.
Botanically interesting habitats within the Sporobolus grassland include seepage areas; wherever
there is any protection from grazing these semi waterlogged habitats support herbs and sedges,
and are worth further investigation.
Vegetation unit 2 (Plate 2)
Montane Hyparrhenia
grassland
o
o
Under steep bluffs at 2117 m elevation; N07 14’46.3”; E12 .09’00.4”, on the northern edge
of the escarpment are areas of Hyparrhenia rufa, with Hyparrhenia sp., Melinis minutiflora, Ludetia
simplex and Andropogon sp. Herbs included an Aloe sp., Blaeria spicata, Euphorbia sp, and
Wahlenbergia krebsii, and bushes Protea madiensis. The influence of past fires was evident,
creating a mosaic of grass species. It was clear that given time and protection from fire Gnidia
woodland would establish here.
Vegetation unit 3 (Plates 2 and 3)
Water seepages / bogs
Most water seepage / bog areas have been destroyed by cattle trampling and subsequent drying
out. One we came across was on some bluffs north of Yangaré at 2275 m elevation; N07o14’26.8”;
E012o08’57.5”, and another at a similar altitude on the path between Fungoi and Mayo Kelele.
Plants collected included several species of grasses, Carex species and small herbs such as a
creeping Hypericum sp. and a small Dissotis sp. This vegetation unit needs further exploration.
1
11
2
Plate 1 Vegetation unit 1. Heavily
grazed Sporolobus africanus between
Fungoi and Mayo Kekele. Cattle,
sheep and horses are common
grazers.
Plate 2 Vegetation units 2 and 3.
Steep bluffs covered with Hyparrhenia
rufa tussocks at 2000 m elevation,
with a water seepage area between
them. The steepness of the terrain
provides natural protection from
grazing and fire.
Plate 3 Vegetation unit 3. The water
seepage area on the main path
between Fungoi and Mayo Kelele.
Several species of Carex, grasses and
her bs wer e collected and are
awaiting identification.
3
12
Vegetation unit 4
Montane escarpment forest (Plate 4)
Above +/- 1700 m montane escarpment forest is confined to the steep slopes of the north /
north west escarpment edge where there is protection from fire and grazing. As with the
montane gallery the escarpment forest is relatively species poor. Where we worked, on the
north facing escarpment edge north of Yangaré between +/- 2166 – 1800 m elevation N07 o
24’06.1”; E12o .08’57.9” it was dominated by Prunus africana reaching only 8 to12 m in height.
They were gnarly and very black, and typically festooned with mosses. Other canopy trees
included Schefflera abyssinica, Nuxia congesta and Syzygium guineense subsp. bamendae. Other
tree species included Allophylus bullatus, Campylospermum flavum, Garcinia smeathmannii and
Pittosporum viridiflorum. Rubiacious shrubs dominated the understory, including Pavetta sp and
Ixora sp. and dense stands of Psychotria pedunculatis.
This forest type is reminiscent of the ‘Prunus africana - Syzygium guineense subsp. bamendaePodocarpus latifolius’ forest at a similar altitude on Gangirwal in GGNP (Chapman and Chapman
2001) although missing is P. latifolius. A similar forest type has also been recorded from the
Ijim forests of Northwest Province (Tame and Asonganyi 1995).
Vegetation unit 5
Submontane escarpment forest
Continuous with montane, and often adjacent to gallery forest, between approximately 1700
m and 1500 m elevation is submontane forest which is often dominated by Symphonia globulifera.
Associated species include Ficus species and Phoenex reclinata. This forest type needs further
botanical investigation.
Vegetation unit 6
Hyparrhenia savanna above 1500 m (Plate 5)
Spurs of Hyparrhenia savanna descend steeply down ridges from bluffs below the escarpment
edge (see vegetation map). Their inaccessibility and steepness protects them from regular
burning and cattle grazing. Vegetation cover varies from almost entirely tussock grasses such
as Hyparrhenia species, Melinis minutiflora and Elusine indica to an open grassland savanna. Tree
species include small Croton macrostachyus, Cussonia barteri, Dombeya ledermanni, Faurea speciosa,
Lophira lanceolata, Maesa lanceolata, Ochna afzelii, Phoenix reclinata and Syzygium guineense var.
macrocarpum. Harungana madagascariensis and Protea madiensis are common shrubs (Appendix
2). We discovered an Aloe sp. at N 07o 14’46.3”; E 012o09’00.4” which is interesting as they
have not been recorded from GGNP or the Kilum Ijim grasslands (Plate 6).
This vegetation type was described by Letouzey (1985) as degraded submontane forest, but
Thomas and Thomas (1996) call it a type of high altitude savanna, which it clearly is. It is
especially interesting botanically because it is rare in West Africa, and it’s equivalent in Gashaka
Gumti has largely been burnt and grazed out. It is not described in Tame and Asonganyi
(1995) for the Ijim Ridge.
13
4
Plate 4 Vegetation unit 4. Montane escarpment forest north of Yangaré. Prunus africana was
the dominant tree with Pittosporum viridiflorum, Schefflera abyssinica and Syzygium guineense subsp.
bamendae present. The white flowered Dombeya ledermannii is common around the forest
edge.
Plate 5 Vegetation unit 6. Hyparrhenia savanna above 1500 elevation. Dombeya ledermannii,
Faurea speciosa and Psorospermum aurantiacum were scattered among the grasses.
Plate 6. Aloe sp. growing below a steep bluff at 2000 m elevation in grassland dominated by
Hyparrhenia rufa.
5
6
14
Vegetation unit 7 (Plate 7)
Hyparrhenia savanna below 1500 m
This is very similar to woody savanna below 1500 m (see below) but is confined to ridges and
hill tops. The main difference is the sparse distribution of trees because of the shallow soil.
This vegetation type is relatively common but covers little area (See Vegetation Map (Shu
2004)). It is well represented in West Africa and not especially interesting botanically.
Vegetation unit 8
Woody savanna / transition forest (Plate 8)
Woody savanna dissected by gallery forest is the main vegetation type between +/- 1500 and
+/- 1000 m elevation. On the west side of Tchabal Mbabo it is dominated by Daniellia oliveri
and Lophira lanceolata, with Anogeissus leiocarpa, Faurea speciosa, Gardenia sp. and Entada africana
common.
Vegetation unit 9
Savanna
Between 700 m - 1000 m elevation such as the Mayo Deo (Plate 9) and the Mayo Ledi (Plate
10) valleys, Uapaca cf togoensis and Isoberlinia doka are the dominant trees. Other common
species include Afzelia africana, Crossopteryx febrifuga, Erythrophleum suaveolens, Ochna afzelii,
Piliostigma thonningii, and Terminalia sp. More species associated with woody savanna are
presented in Appendix 3.
15
7
Plate 7 Vegetation unit 7. Hyparrhenia dominated grassland confined to ridges running from
the escarpment edge down towards the Mayo Yim .
Plate 8 Vegetation unit 8. Woody savanna/ transition forest below Ndongawa. Common tree
species include Albizia gummifera, Croton macrostachyus, Dombeya ledermannii, Faurea speciosa,
Phoenix reclinata, Psorospermum aurantiacum and Syzygium guineense subsp.macrocarpa.
8
16
Vegetation unit 10
Lowland savanna
Lowland savanna (below 700 m) often differs from savanna at higher altitude by the dominance
of Isoberlinia doka. Monotes kerstingii is characteristically abundant.
Vegetation unit 11
Montane gallery forest (Plates 9 and 10)
Above +/- 1800 m montane gallery forest borders most drainage areas, sometimes only a few
meters wide. At this altitude the forest is species poor, and generally only 8-12 m high. Species
composition varies according to site, and three examples are presented below (Table 3).
Table 3
Vegetation types within the vegetation unit 11: Montane gallery forests
2i) Ilex mitis dominated
2ii) Syzygium guineense sub sp. cf bamendae dominated
2iii) Albizia gummifera – Nuxia congesta- Prunus africana dominated
2i Ilex mitis stream fringing forest (Yangaré area, +/- 2000 m in elevation)
This forest type is usually confined to a strip only a few meters wide on either side of streams
which dissect the Sporobolus grassland. The fragments are typically infiltrated by cattle, and
suffer from burning. Ilex mitis is abundant, and other woody species include Agarista salicifolia,
Allophylus bullatus, Bersama abyssinica, Prunus africana, Bridelia speciosa, Clausena anisata, Cyathea
dregei, Eugenia gilgii, Ixora foliosa, Maesa lanceolata, Pittosporum mannii and Xymalos monospora.
The grassland / forest ecotone is very narrow and sometimes absent, but typically includes the
shrubs Hypericum lanceolatum and H. roeperanum, and the tall herbs Dissotis perkinsiae, Pycnostachys
meyeri, Geniosporum rotundifolium and Brillantaisia owariensis. Bracken fern Pteridium aquilinum
is common. For a more detailed species list see Appendix 2. Noticeable for its absence
compared with similar forests on Gangirwal is Cyathea manniana.
2ii Syzygium guineense subsp. bamendae dominated forest (Yangaré to Tchabal
Mbabo village, and in the Fungoi area; 2000 -2300 m in elevat ion).
Species typically associated with Syzygium guineense subsp. bamendae forest include Nuxia
congesta, Bridelia speciosa, Clausena anisata, Cyathea dregei and Ilex mitis. The Threatened Salix
ledermanii is sometimes present. Edge species are the same as for Ilex mitis dominated forest,
and include Hypericum lanceolatum, Dissotis perkinsiae, Pycnostachys meyeri, Geniosporum rotundifolium
and Brillantaisia owariensis. These fringing forests are used as a source of firewood, and also
suffer from cattle trampling and burning. This vegetation type most resembles the ‘Syzygium
guineense subsp. bamendae stream source forest’ at 2130 m elevation on Gangirwal, GGMP
(Chapman and Chapman 2001).
2iii Albizia gummifera – Nuxia congesta- Prunus africana dominated forest
(Fungoi area at +/- 2000 m elevation)
Around Fungoi the stream fringing forest was relatively undisturbed, although cattle and fire
are still an issue. Typical abundant species include Albizia gummifera, Allophylus bullatus, Nuxia
congesta and Prunus africana. Also common are Bersama abyssinica, Bridelia speciosa, Clausena
anisata, Cyathea dregei, Eugenia gilgii, Ilex mitis, Ixora foliosa, Maesa lanceolata, Phoenix reclinata,
and Xymalos monospora. Olea capensis and Pittosporum viridiflorum were also recorded (Appendix
2). This forest type closely resembles the ‘Albizia gummifera – Nuxia congesta forest at 1830
m in elevat io n on C habbal Wad di, GGNP (C hapm an and Chap man 200 1).
17
9
Plate 9 Vegetation unit 11. Ilex mitis dominated gallery forest. The purple flowered herb Dissotis
perkinsiae is extremely common along the forest edge.
Plate 10 Vegetation unit 11. Depleted montane gallery forest with Syzygium guineense subsp.
bamendae, Ilix mitis and Croton macrostachyus.
Plate 11. Syzygium guineense subsp.macrocarpa was flowering abundantly in 2004.
10
11
18
Vegetation unit 12
Submontane gallery forest (Plates 12, 13 and 14)
Submontane gallery forest (between +/- 1500 -1800 m) are more species rich, with taller trees
(emergents reach 30 m in height) than the montane galleries.. A gallery we studied in detail
was dominated by Pouteria cf altissima and Pterygota cf mildbraedii (Ndongawa: +/- 1923 m;
N07o18’57.8”; E012o12’48.0).
Facing WNW this gallery forest is confined within a deep, steep valley of approximately 200
m wide at the top, but spilling into a more extensive forest below. Canopy trees were Pterygota
cf mildbraedii (in full fruit), Pouteria cf altissima (in flower) and Ficus spp., all reaching +/- 30 m
in height. Associated common trees included Albizia gummifera, Bersama abyssinica, Croton
macrostachyus, strangling Ficus spps. and Schefflera abysinica. Millettia conraui, and Nuxia congesta.
Cola sp., Phoenix reclinata, Prunus africana and Rauvolfia vomitoria were also present. At the top
end of the forest the undergrowth was thick with Palisota cf hirsuta and Acanthus species,
including A. montanus. Piper capense and Boehmeria platyphylla were both in flower and Leea
guineensis in fruit. Lower down in the forest the understory became much less dense, and
saplings of Cola sp., A. gummifera, and Milletia conraui were obvious.
In a nearby gallery (1824 m; N07o 18’59.8”; E012o 12’35.9) additional species included Ficus
exasperata, Rothmannia urcelliformis (in flower) and Solanecio mannii. What looked like Newtonia
buchananii and Khaya cf grandifoliola were noted.
Another type of submontane gallery (on the path between Ndongawa and Mayo Ledi - Mayo
Barka camp at +/- 1721 m -1500 m; N07o18’57.0”; E012o 12’09.8, and between the Mayo Selbe
and Fungoi camp N07o18’35.1”; E011o59’48.0 at a similar altitude) was dominated by the palm
Phoenix reclinata and Symphonia globulifera. This vegetation type is absent from GGNP; although
some Phoenix reclinata is found in the forest on Gangirwal, it is nothing like as common as on
Tchabal Mbabo, nor are the individuals as large.
Vegetation unit 13
Lowland gallery forest (Plate 15)
Gallery forest fringes the rivers and streams between 1500 – 700 m elevation, except near
villages such as Dodeo where it is replaced by tall grasses.
By the Mayo Ledi at 718 m (N 07o 22’21.2”; E 012o 07’01.0) typical gallery species included
Berlinia grandiflora, Khaya senegalensis, Parkia biglobosa and Syzygium guinense subsp. guineense.
Representative smaller trees and shrubs included Coffea sp., Diospyros mespiliformis, Ochna afzelii,
Polysphaeria arbuscula, Rapanea melanophloeos and Salix ledermanii (Plate 17). Interesting herbs
such as a semi-aquatic Polygala sp. were noted by the riverside.
While the gallery forest is mainly comprised of common species and is well represented as a
vegetation type in West Africa, it is extremely important as a habitat for wildlife.
Similar savanna and gallery forest is widespread at a similar altitude in GGNP, especially in the
northern sector (Dunn 1999).
Vegetation unit 14
Afromomum-Hallea stipulosa-Allophylus swamp forest above 2000 m.
Probably once common, we found only one remnant of Hallea stipulosa swamp forest close
to Tchabal Mbabo village at 1710 m elevation; N 07o 15’16.2”; E 012o15’19.1”. The few surviving
individuals were approximately 15 m tall, growing with Allophylus africanus and Ficus sp.
Afromomum cf angustifolium formed a dense understory, and the whole area was waterlogged.
H. stipulosa is much coveted for it’s timber, which explains its rarity.
Noticeable for their absence as compared with similar forest types on Mabilla Plateau (Nigeria)
were the tree species Polyscias fulva and Anthocleista vogelii, both uncommon anywhere on
Tchabal Mbabo.
19
12
13
Plates 12 and 13. Vegetation unit 12.
Submontane gallery forest at 1800 m elevation
near to Ndongawa. Phoenix reclinata is
common here.
15
Plate 14. Seed and half a fruit pod of the
emergent tree Pterygota cf mildbraedii at 1800
m elevation.
Plate 15 Vegetation unit 13. Lowland gallery
forest along a tributary of the Mayo Deo at
700 m elevation.
14
20
Vegetation unit 15
Montane forest-grassland ecotone (Plates 16, 17 and 18)
The forest-grassland ecotone is dominated by the fire resistant tree Gnidia glauca, and is
common below steep, inaccessible bluffs round the escarpment edge where there is some
protection from fire and grazing. The ecotone we studied was on the north edge of the
escarpment, north of Yangaré above 2000 m elevation at N07o 14’46.3”; E012o 09’00.4.
Associated woody species include the Ericaceous shrubs Erica mannii and Agarista salicifolia, the
fire resistant Hypericum lanceolatum and H. roeperianum, Maesa lanceolata and Psorospermum
aurantiacum and P. densipunctatum. The understory is dense with ferns and herbs, especially
Pteridium aquilinum and various Labiatae such as Pycnostachys meyeri, Satureja and Scutellaria
species and Geniosporum rotundifolium. The IUCN threatened Peucedanum angustisectum was
common. Observations suggest this vegetation type is transient and dependent upon protection
from fire. When burnt grassland is re-established.
It is botanically interesting and quite different to the forest edge community in Gashaka Gumti
where Gnidia glauca is present but never abundant. It is similar to the forest / grassland ecotone
of the Ijim forests of Northwest Province (Tame and Asonganyi 1995) and the upper montane
forest : grassland edge on Mt Oku Cheek et al. 2000).
Vegetation unit 16 (Plate 19)
Cultivated flood plains with Pennisetum purpureum
Tall grassland interspersed with cultivation and fallow is common along flood plains of streams
and rivers such as the Mayo Deo and its tributaries. Pennisetum purpureum is often dominant
with Sacharrum spontaneum and Urelytrum giganteum.
16
21
18
17
Plate 16 Vegetation unit 15. Gnidia glauca
woodland between escarpment forest and
Hyparrhenia savanna at 1900 m. No cattle ever
graze here and fire is infrequent.
Plate 17 Vegetation unit 15. Erica mannii forms
a dense thicket along the forest edge at 1900
m elevation, close to the Gnidia glauca woodland
above.
Plate 18 Vegetation unit 15. Peucedanum
angustisectum reaches 1 m tall under Gnidia
glauca in the forest-grassland ecotone.
Plate 19 Vegetation unit 16. Pennisetum
purpureum is often dominant with Sacharrum
spontaneum and Urelytrum giganteum. Here
growing along the flood plain of the Mayo Deo
at 650 m elevation.
19
22
Comparisons with previous surveys
Comparisons in terms of mapping and vegetation units between Thomas and Thomas (1996)
and this survey are presented in Table 4 and discussed on page 8. Here we compare surveys
in terms of species composition.
The 2004 survey is the most detailed botanical survey ever of Tchabal Mbabo, adding considerably
to the findings of Thomas and Thomas (1996). While the 1996 report identified most of the
broad vegetation types and common species, our survey distinguished several forest types
within the montane and submontane altitudinal zones (Table 3), and added to the more
uncommon and rare species. For example the threatened herbs Lobelia columnaris (Plate 21)
and Peucedanum angustisectum (Table 5) are relatively common on the northern edge of the
escarpment. We also discovered a species of Aloe which has yet to be identified (Plate 6), and
has not been recorded from other Cameroon mountains or the neighboring Gotel mountains
in Nigeria. The threatened tree species Khaya grandifoliola and Pouteria altissima need confirmation,
but are likely on Tchabal Mbabo. Pterygota mildbraedii, rare in West Africa, appears to be
present.
Several additions were made to the montane / submontane tree species list including Anthocleista
vogelii (Loganiaceae), Chrysophyllum albidum (Sapotaceae), Olea capensis (Oleaceae), and Polyscias
fulva (Araliaceae). We undoubtedly have many more additions which are awaiting identification.
The important timber tree, Hallea stipulosa was noted for the first time on Tchabal Mbabo
during this survey.
23
Table 4 Comparison between the recognized vegetation units in the Thomas and
Thomas (1996) report and this 2004 survey.
Zones
Thomas and Thomas
Chapman and Shu
(1996)
(2004)
Mapped Vegetation
Units
Montane
Included Vegetation
Types
Mapped Vegetation
Units
> 1700
Montane prairie
Included Vegetation
Types
> 1700
Montane galleries
Montane escarpment
forest
Prunus africana
dominated forest
Saxicolous
Afromomum swamp forest
Cultivation
Grassy ridge tops
Montane
forest/scrub
Saxicolous
Montane gallery forests Ilex mitis dominated forest
(above 2000 m)
Syzygium guineense sub
sp. cf bamendae
dominated forest
Albizi Albizia gummifera
– Nuxia congesta- Prunus
africana dominated forest
Montane forest –
grassland ecotone
Montane
Hyparrhenia grassland
> 1500 m
Not recognised
Overgrazed Sporolobus Water seepages / bogs
africanus grassland
Cultivation
Hyparrhenia savanna
Submontane
1700-1200 m
2000 – 1500 m
Savanna +/- wooded
Gallery forest
Cultivation
Submontane escarpment
forest
Submontane gallery
forest
Mid-elevation
savanna
1200-800 m
1500-700 m
Savanna woodland
Hyparrhenia savanna
Woody savanna/
transition forest
Lowland gallery forests
Lowelevation
savanna
800-500 m
Savanna woodland
<700
Gallery forest
Lowland Savanna
Other riparian
Fallows
Cultivation
24
Lowland gallery forests Cultivated flood plains
with Pennisetum
purpureum
Priority localities for biodiversity
conservation
(zones of high/medium/low biodiversity interest) from a botanical point of view.
Z on es of h i gh b i od i ve r si ty i n ter e st o n Tch ab al Mb ab o i n cl u d e:
1. Montane forests (vegetation units 4 and 11)
The montane forests of Tchabal Mbabo belong to the Afromontane archipelago-like regional
centre of endemism (White 1983). They are arguably the most significant forest type in West
Africa (Sayer et al. 1992; White 1978), with a high proportion of species (near-) endemic to
the Afromontane region, and a floristic affinity with East African montane floras (Morton 1972).
The Tchabal Mbabo forests are of an especially rare, dry type (Thomas and Thomas 1996).
Before comments can be made as to narrow endemic plant species, further botanical work is
necessary.
Table 5 lists the IUCN globally threatened plant species recorded in these forests.
The escarpment forests on Tchabal Mbabo represent unspoilt examples of West African
montane / submontane and transition forest. While they are not rich in terms of species
numbers, the ecosystem is rich in biodiversity value. Forest composition is subtly different to
the Gotel Mountains of GGNP, and so these forests complement their Nigerian equivalent.
For example, the extensive stands of Prunus africana occurring on the north facing escarpment
of Tchabal Mbabo are not duplicated in GGNP. Tchabal Mbabo forests are less species rich
than the Gashaka ones, especially at altitudes around 1600- 1800 m, but have a more developed
forest ecotone.
The stream side fringing forests which dissect the Sporobolus grassland are much more extensive
than those in Gashaka Gumti. This ecosystem is probably very similar to what Mambilla Plateau
(outside GGNP) would have looked like 40-50 years ago. As well as being botanically interesting
(Appendix 1) the plateau fringing forests are essential for maintaining year round water supply
and are habitat for many birds and other animals and insects. It is imperative that they be
offered strict protection.
2. Montane Hyparrhenia grassland (vegetation unit 2)
Montane grassland free from cattle grazing is rare in West Africa. It has almost become extinct
within GGNP, Nigeria (Chapman et al. 2003) and is absent from the Ijim montane area of
Cameroon (Tame and Asonganyi 1995). With further study many more trampling sensitive
herbs may be discovered.
3. Montane forest - grassland ecotone (vegetation unit 15)
The Gnidia glauca dominated forest-grassland ecotone is very species rich; it is habitat for light
demanding, trampling sensitive plants such as the IUCN Threatened Peucedanum angustisectum,
which here reaches 1 m in height, and many species of fern. Tame and Asonganyi (1995)
emphasise the important role played by the ecotone in protecting the forest from fire.
4. Water seepages / bogs (vegetation unit 3)
Permanently wet water seepage areas are relatively uncommon on Tchabal Mbabo but are
species rich and therefore of high biodiversity int erest . They need more study.
5. Submontane escarpment and gallery forests (vegetation units 5 and 12) and Hyparrhenia
savanna >1500 m (vegetation unit 6)
The submontane forests of Tchabal Mbabo also belong to the Afromontane archipelago-like
regional centre of endeminism (White 1983). Both the escarpment and gallery forests are
valuable as part of a continuum from lowland to montane ecosystems, and as a reservoir of
rare species such as the IUCN Threatened Dombeya cf ledermannii.
25
6. Woody savanna transition forests (vegetation unit 8)
The transition between lowland and montane forest is a very rare situation in West Africa.
Thomas and Thomas (1996) suggest that the Tchabal Mbabo transition forest is the best
example in this area of Cameroon. A similar transition, differing in detail, occurs in GGNP.
7. Lowland gallery forests (vegetation unit 13)
Species composition of the gallery forest below +/- 1500 m is similar to the equivalent
ecosystem in GGNP. However its extent and its relatively good condition make for a valuable
conservation area.
Zon es of med iu m bi odi ver sity in terest on Tch ab al Mb abo i nc lu de:
1. Hyperrhenia savanna < 1500 m (vegetation unit 7) ; 2. Savanna (vegetation unit 9);
3. Lowland savanna (vegetation unit 10)
While none of these vegetation units are rare in West Africa and do not harbour rare species,
they are important in terms of the whole ecosystem function and offer valuable habitat for
wildlife.
3. Afromomum swamp forest (vegetation unit 14)
Although presently degraded, if allowed to regenerate this forest type would become of high
biodiversity interest because it is so rare. It is not mentioned in the reports of either the Ijim
mountains (Tame and Asonganyi 1995) or Mt Oku (Cheek et al. 2000), and has become extinct
on Mambilla Plateau during the past twenty years (Chapman and Chapman 2001).
Zones of low biodiversity interest on Tchabal Mbabo include:
1. Sporobolus grasslands (vegetation unit 1)
While the degraded Sporobolus grasslands themselves are species depauparate they are dissected
by valuable stream fringing forests, and harbor diverse water seepage areas (see above).
2. Lowland river valleys with cultivation and Pennisetum purpureum (vegetation unit 16)
The cultivated flood plains and dense stands of tall grasses including Pennisetum purpureum are
common in West Africa and are not especially species diverse. They do however provide
valuable bird habitat.
26
Table 5
IUCN Red Data List species in the montane / submontane ecosystem of Tchabal Mbabo include:
†
Species
IU CN Red Data Li st category
Chassalia laikomensis Cheek ined.
Dombeya cf ledermannii Engl.
Eugenia gilgii Engl. and Brehm.
Helichrysum cameroonense Hutch. and Dalziel.
Khaya grandifoliola C. DC.
Lobelia columnaris Hook. f.
Millettia conraui Harms.
Peucedanum angustisectum (Engl.) Norman
*Pouteria altissima (A. Chev.) Baehni.
Prunus africana (Hook. f.) Kalkman
CR A1
CR A1c
CR A1c
LR/nt
VU A1cd
LR/nt
VU A1c, B1+2c
LR/nt
LR/cd
LR/nt
* needs conformation from Kew
(CR) Critically Endangered; (VU) Vulnerable (to extinction); LR Near Threatened.
†
A more detailed explanation of all designated categories is given in IUCN (2000), and at
http://redlist.cymbiont.ca/categories_criteria.html.
20
21
Plate 20 Dombeya ledermannii, an IUCN Threatened species, is common along the forest edge
between 1800- 2000 m all over Tchabal Mbabo.
Plate 21 The IUCN Threatened Lobelia columnaris is confined to edges of forest patches (often
along stream banks) which are protected from heavy grazing.
27
Threats to biodiversity
The main threats to plant biodiversity of Tchabal Mbabo currently come from the local Fulbe
people in the form of burning, cattle grazing, wood cutting, and land clearance for farming. Non
resident contractors are devastating populations of Prunus africana by bark stripping, and if
roads are developed into the Dodeo area potential threats from other non residents, such as
tree felling, would increase.
The north facing escarpment forests between Fungoi and Yangaré are naturally well protected
from fire, cattle grazing and anthropogenic use by steep, relatively inaccessible bluffs.
The forests on the west facing slopes are not as well protected, and the main path from Tchabal
Mbabo village to Dodeo passes this way. Threats to these forests include burning (from which
they are somewhat naturally protected by being confined to steep gullies) and the cutting down
of trees for fence posts, construction and firewood. On the path close to the Ndongawa camp
site are several stumps of trees which have been recently felled, presumably by the local Fulbe.
If their population increases so will the pressure on these forests. As Thomas and Thomas
(1996) suggest, opening a road into Dodeo would exacerbate such problems, as the forests
would then become accessible for timber and P. africana exploitation from below.
Streamside fringing forest (vegetation units 11 and 12) across the plateau and on the escarpment
edge is being whittled away by annual burning, cattle trampling and cutting for firewood and
poles. The latter was apparently rare in 1996 (Thomas and Thomas) but during this survey
women were seen and heard cutting trees on several occasions. Land with riverine strips is
sometimes cleared for farming.
Particular species which are exploited include the timber tree Hallea stipulosa, and Prunus
africana. The latter is commercially valuable for its medicinal purposes as the bark contains a
complex of compounds used in the treatment of prostate cancer. Trees are completely stripped
of bark and consequently die. This was most apparent in the Mayo Kelelé area. Our cook was
from a ‘Prunus camp’, and he told us that fifteen more men were soon to arrive in the area
with permits to collect bark. If not controlled, this practice will lead to the decimation of Prunus
from all but the most inaccessible forests.
The main threats to savanna (vegetation units 9 and 10) include burning and grazing, but because
most of this vegetation type is confined to steep slopes, or is in areas where there are tsetse,
it is not particularly threatened.
The savanna woodland is burned annually during the mid-late dry season, and this management
has been applied for a long time (Thomas and Thomas 1996). It does not pose a threat to the
current vegetation which has evolved with fire. The areas covered in this survey are not
overgrazed because of the presence of tsetse.
28
Recommendations for conservation and
management
This report agrees in principle with the four management zones proposed by Thomas and
Thomas (1996).
All escarpment forests should be included in zone 1, a protected area, with no allowance for
the harvest of forest products. This zone should include an altitudinal range from 2000 m +
to +/- 1400 m, to incorporate both montane / submontane and transition between lowland
and montane forest.
The plateau, overgrazed Sporobolus grassland, should be zoned for rural development (zone
2). However within this zone the streamside fringing forests need strict protection. This is
challenging as the fringing forests dissect the grassland, and the Fulbe depend on them for
firewood and poles. Nonetheless, if they are to continue having an important conservation
value they need sufficient protection to ensure they maintain their ecological integrity. This
might be achieved by designating as protected area, zone 1, some parts of the plateau areas
with representative types of fringing forest and low population density (such as the Yangaré
and Fungoi areas). Cattle could be excluded and burning strongly controlled. Within zone 2
pressure could also be removed from fringing forest by the introduction of more Eucalyptus
(or preferable fast growing and suitable natives such as Croton machrostachys and Hallea stipulosa)
woodlots. Strict patrols would be necessary to ensure that woodlots are used in place of the
fringing forest for firewood and poles; on neighbouring Mambilla Plateau in Nigeria the fringing
forest has been almost totally decimated despite the introduction of Eucalyptus during the
1960’s.
A system of grazing management could be implemented to prevent overgrazing of the plateau
grassland and reintroduce floristic diversity.
The unsustainable harvesting of Prunus africana should be halted. If licenses for bark removal
are issued, quotas must be strictly monitored and adhered to. An education programme on
how to remove bark in a sustainable manner (as has been introduced in other parts of
Cameroon) should be implemented. Nurseries of P. africana should be created, with education
on propagation and marketing.
Zone 3, the Dodeo plain, is suited for rural development. However if road access is introduced
it will make the escarpment forests much more vulnerable to exploitation of both plants and
animals. This factor needs careful consideration, and a solution might be a buffer of zone 1
between the plain and the bottom of the escarpment.
This survey did not spend sufficient time outside the proposed zones 1, 2 and 3 of Thomas
and Thomas (1996) to make an informed recommendation concerning their proposed zone
4.
29
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30
Appendix 1
Preliminary species inventory for the montane and submontane forests and
galleries of Tchabal Mbabo: vegetation units 4, 5 and 11.
Forest species (woody plants)
Albizia gummifera
Allophylus bullatus
Anthocleista vogelii
Bersama abyssinica
Brachystegia eurycoma
Bridelia sp.
Bridelia speciosa
Chassalia sp.
Chrysophyllum albidum
Clausena anisata
Cola gigantea
Croton macrostachyus
Cyathea dregii
Dombeya ledermannii
Dracaena arborea
Dracaena fragrans
Eugenia gilgii
Ficus exasperata
Ficus spp.
Ficus sur
Ficus vallis-choudae
Gnidia glauca
Hallea stipulosa
Harungana madagascariensis
Ilex mitis
Ixora foliosa
Leea guineensis
Maesa lanceolata
Malacantha alnifolia
Millettia conraui
Neoboutonia cf velutina
Nuxia congesta
Ochna afzelii
Olea capensis
Palisota mannii
Paullinia pinnata
Pittosporum viridiflorum
Polyscias fulva
Pouteria altissima
Prunus africana
Psorospermum aurantiacum
Psorospermum densipunctatum
Psychotria peduncularis
Pterygota cf mildbraedii
Rauvolfia vomitoria
Rothmannia urcelliformis
Rytigynia umbellulata
Salix ledermanii
Schefflera abyssinica
Symphonia globulifera
Strombosia scheffleri
Syzygium guineense subsp. bamendae
Syzygium guineense subsp. guineense
Trema orientalis
Vepris sp.
Xylopia sp.
Xymalos monospora
Forest edge species
Acanthus montanus
Adenocarpus mannii
Agarista salicifolia
Alchemilla sp.
Boehmeria platyphylla
Clematis sp.
Cyathea dregei
Dissotis perkinsiae
Erica mannii
Geniosporum rotundifolium
Geranium arabicum
Gnidia glauca
Hibiscus noldeae
Hypericum lanceolatum
Hypericun roeperanum
Hypoestes verticillaris
Jasminum pauciflorum
Kalanchoe crenata
Lobelia columnaris
Protea madiensis
Pteridium aquilinum
Pycnostachys meyeri
Rubus cf fellatae
Sebaea brachphylla
Sesbania macrantha
Solanecio mannii
Solanum sp.
Tephrosia
Tephrosia vogelii
31
Appendix 2
Preliminary species inventory for the montane / submontane forest–grassland
ecotone:vegetation unit 15.
Adenocarpus mannii
Agarista salicifolia
Crassocephalum mannii
Dissotis perkinsiae
Erica mannii
Faurea speciosa
Geniosporum rotundifolium
Geranium arabicum
Gnidia glauca
Hypericum lanceolatum
Hypericum riparium
Hypericun roeperanum
Maesa lanceolate
Nuxia congesta
Pteridium aquilinum
Pycnostachys meyeri
Appendix 3
Preliminary species inventory for the savannas of Tchabal Mbabo: vegetation
units 6,7,8,9,and 10.
Acacia sp.
Adansonia digitata
Afzelia africana
Allophylus bullatus
Anona senegalensis
Antidesma venosum
Borassus aethiopum
Bridelia ferruginea
Bridelia scleroneura
Burkea africana
Combretum glutinosum
Combretum lamprocarpum
Crossopteryx febrifugum
Croton macrostachyus
Cussonia barteri
Daniellia oliveri
Entada africana
Erythrina senegalensis
Vitellaria paradoxa
Detarium microcarpum
Dichrostachys cinerea
Erythrina sigmoidea
Faurea speciosa
Ficus spp.
Flacourtia flavescens
Garcinia smeathmannii
Gardenia sp.
Grewia mollis
Harungana madagascariensis
Hymenocardia acida
Hyperrhenia spp.
Isoberlinia doka
Isoberlinia tomentosa
Khaya senegalensis
Lannea kerstingii
Lophira lanceolata
Monotes kerstingii
Nauclea latifolia
Ochna afzelii
Parinari curatellifolia
Parkia biglobosa
Phoenix reclinatus
Phyllanthus muellerianus
Piliostigma thonningii
Prosopsis africana
Protea madiensis
Pseudocedrela kotschii
Psorospermum febrifugum
Psorospermum glaberrimum
Pterocarpus erinaceus
Pterocarpus lucens
Securidaca longipedunculata
Sterculia setigera
Stereospermum kunthianum
Syzygium guineense subsp. guineense
Syzygium guineense subsp. macrocarpa
Terminalia mollis
Terminalia sp.
Trichilia emetica
Uapaca togoensis
Vitex doniana
32
Appendix 4
Preliminary species inventory for the lowland gallery forests of Tchabal Mbabo:
vegetation unit 13.
Albizia gummifera
Anthocleista djalonensis
Berlinia grandiflora
Brachystegia euyrycoma
Coffea sp.
Daniellia oliveri
Diospyros mespiliformis
Khaya senegalensis
Landolphia sp.
Leea guineensis
Ochna afzelii
Paullinia pinnata
Polysphaeria arbuscula
Psychotria peduncularis
Rapanea melanophloeos
Salix ledermannii
Syzygium guineense subsp. guineense
Vitex doniana
33