Status of Large Marine Flagship Faunal Diversity Within Cameroon Estuaries of Central African Coast - The Land/Ocean Interactions in the Coastal Zone of West and Central Africa - page 97

Methods

of low-altitude Atlantic forest, preceded on the seaward side
by patches of a few species of grass which grow on the
beaches.
• From River Nyong to Limbe
The coast is low and is characterized by the presence of
estuary and riverine mangroves, separated from the Atlantic
forest by a marshy complex of brackish waters. The rivers
here are Dibamba, Wouri, Mungo and Sanaga. These
waterways have high discharges and transport huge quan-
tities of sediments towards the sea. The Mungo enters the
sea through a delta, while other rivers enter together through
the estuary (Dibamba, Wouri and Sanaga). The creation of
the Douala-Edea Wildlife Reserve has been justified by the
great fauna diversity in the area.
• From Limbe to Idenau
The coast is volcanic and is overhung by Mount Cam-
eroon which has a peak of 4,095 m at the level of Fako. The
vegetation is made up of low-altitude mountain forest rich
in endemic species. It is characterized by lava flows and the
industrial plantations of the Cameroon Development Cor-
poration (CDC). These plantations currently cover more
than 90,000 ha. The Mabeta-Moliwe reserve is found here.
• From Idenau to the Nigerian border
The coast is once more low and marshy; this part of the
coast is watered by the mouths of rivers Akwayafe, Ndian,
Lokete and Meme which together enter the sea through the
Rio-Del-Rey estuary. The vegetation consists of mangroves
and swampy species. In the hinterland, the Atlantic forest
includes the Korup rainforest and national park.

Cameroon Coastal Profile and Study Sites

The coastal zone of Cameroon stretches over 402 km
(Sayer et al. 1992 ), from the Nigerian border in the north
(Akwayafe River, latitude 440 0 N) to the Equatorial Guin-
ean border in the South (Campo River, latitude 220 0 N),
falling between longitude 815 0 E and 930 0 E).
The vegetation of this region belongs to the large set of
massive dense humid forest of Cameroon in low and
medium altitudes in the coastal forest group, consisting of
dense vegetation moist evergreen lowland to Sagoglottis
gabonensis and Lophira alata, biafran subtype; this primi-
tive forest is similar to South American affinities with the
humid Amazon rainforest (Letouzey 1968 ).

Cameroon Continental Shelf
The continental shelf of Cameroon occupies an area of
about 10,600 km 2 and gradually descends through 30, 50
and 100 m depths (Bye et al. 1974 ; Zogning 1986 ; Morin
and Kuete 1989 ). The northern part has a width of about 25
nautical miles on average, while the southern portion is
narrow (15 nautical miles on average). Its relief shows two
distinct zones separated by a parallel which passes through
the mouth of the Lokoundje River. In the north, the slope is
gentle, with a drop in altitude of 130 m. This zone is rocky,
with intermittent occurrence of sandbanks. Meanwhile, two
major faults have been identified: a reef north of the mouth
of the Sanaga River and a series of outliners in the neigh-
bourhood of Macias Nguema Island (Bioko-Equatorial
Guinea). This area is favourable for trawling (industrial
fishing) (Crosnier 1964 ). South of this parallel, the relief of
the continental shelf is more disjointed; there are many reefs
and sandbanks. The interruption of the slope occurs quite
early (e.g. at 50 m depth between Campo and Kribi). This
area is not suitable for trawling, but is favourable for small-
scale fishing. Many corals can be found at 150 m depth.

Geological Characteristics

Sedimentary Basin
The Cameroon coast includes three sedimentary basins of
different dimensions. These are the Campo-Kribi basin, the
Douala basin and the Rio-del-Ray basin. The Campo-Kribi
basin covers an area of 45 km 2 (1-3 km wide and 25 km
long). It is situated north of the River Ntem, and its fossils
give it great paleogeographic importance. The increase
varies between 30 and 100 m. The slope variations mea-
sured at sea are a reflection of the situation obtained on
land. This can be explained by the existence of many recent
faults parallel to the coast and rising several metres above
the base. These faults are associated with the formation of
the Congo basin, the Lobe waterfall and the Ntem and
Bongola rapids. The Douala Rio-del-Rey basin stretches
from latitudes 20 to 50 North. It is made up of two sub-
basins: the Douala basin in the east (7,000 km 2 ) and the
Rio-Del-Rey basin in the west (2,500 km 2 ). From south to
north, one passes successively through symmetrical geo-
morphologic settings on both sides of Mount Cameroon: the

Coastal Landscape and Hydrology
According to Kramkimel and Bousquet ( 1987 ), four char-
acteristics areas can be distinguished within the Cameroon
coastal landscape:
• From Campo to the River Nyong mouth
The coast is high and shows an alternation of rocky
outcrops and sandy mud. The main rivers are Ntem, Lobe,
Kienke, Lokoundje and Nyong. Their discharges are low,
and they transport little alluvium towards the sea. Man-
groves are slightly represented; when present, they are in
the form of patches on a rocky substrate; this is comparable
to the situation described by Villiers ( 1973 ) along the
Gabonese coast. On the continent, the vegetation is made up