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Environmental and bioeconomic characterisation of coastal and
marine systems of Cameroon, including risk implications of the
Chad-Cameroon pipeline project
Andrew R.G. Pricea , Rebecca
Klausb, Charles R.C. Shepparda,
Mark A. Abbissa, M. Kofanib,
Graham Webstera
aEcology and Epidemiology Group, Department
of Biological Sciences, University of Warwick, Coventry CV4
7AL, UK
b c/o WWF-Cameroon, B.P. 6776, Yaoundé, Cameroon |
Abstract
We assess the status of Cameroon's coastal and marine
environment, from field survey results and analysis of existing
environmental and bioeconomic datasets. The study was undertaken
at a broad level, and at greater resolution in the area likely to
be influenced by the Chad-Cameroon pipeline. Thirty-six coastal
sites are characterised using a proven, robust environmental assessment
technique. Solid waste was more prevalent and abundant than beach
oil, and both were most common around Douala towards Kribi. Offshore
sampling was undertaken at 77 sites, 80% of which were dominated
by mud or silt fractions, whereas hard substrata were uncommon.
Key biological resources were identified in 3 main areas
of the Cameroon coast, from analysis of existing environmental data,
using a Geographic Information System: (1) northern region around
Ndian (mangroves); (2) central region in and around Douala (mainly
mangroves and including a protected area); and (3) southern region
between Kribi and Campo (mangroves including a protected area).
Coastal uses/pressures are greatest around Douala, an area associated
with at least five different major uses/pressures. Other parts of
the coast appear to have fewer uses/ pressures, although these areas
are extensive. Coastal areas where concentrated biological resources
coincide with coastal uses/pressures are extensive, encompassing
much of the coastal zone. These are indicative of resource-use conflicts,
where management action should be a high priority. Areas where biological
resources coincide with multiple/heavy coastal uses and pressures
are fewer and less extensive.
Cameroon's coastal resources (e.g., fisheries) are of
direct significance. Their ecosystem services are also important,
an estimated US$8.3 billion y-1
nationally. This is equivalent to US$600 person -1
y-1, a figure approximating per
capita gross national product (US$610). Within the project area,
ecosystem services may be c. US$1.5 billion y-1,
or US$105 person-1 y-1.
Estimated project benefits from royalties are equivalent to only
US$4 person-1 y-1
over 30 years and about 1700 jobs. Major project costs are c. US$1.8
billion. Valuations of both ecosystems and the project necessarily
make assumptions. Nevertheless, even large reductions in individul
habitat values do not undermine the remarkable overall value of
ecosystem service and natural capital, nor their importance in cost-benefit
analysis.
Our assessment of overall risk of coastal oil pollution
in the project area combines probability of spillage (based on previous
work), and a modified index of environmental sensitivity. This estimates
the extent of coastline and habitats at risk, and associated degree
of overall risk. High risk areas include: (1) area between Enyangoe
and Ondja (north/central project area); (2) area from Loiaba to
south of Biyo (south/central project area); and (3) segment of coast
to the north and south of Campo (south project area). The same process
can be applied using different oil spill scenarios or more comprehensive
datasets.
Keywords: Ecosystem status; Integrated assessment; Geographic information
system (GIS); Oil pollution;
Sensitivity
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