NDOH MBUE INNOCENT
China University of Geosciences, Environmental Sciences and Engineering, China
Land cover and its configuration in the landscape are crucial components in the provision of biodiversity and ecosystem services. In savannah watersheds, natural landscapes mostly covered by a mixed of montane forest, grassland, shrubs and grasses have been to a large extent transformed into cultural landscapes since long time ago. We investigated land cover changes in Kilum/Ijim Mountains and surrounding watershed using multi-temporal satellite imagery taken in 1978, 1988, 2000 and 2008. The major trends in this dynamic landscape were reduction of water bodies, transformation of primary forest and conversion of shrubland/grassland to intensive land uses such as farmland. The average net annual deforestation rate was 5.6%, and shrubland reduction occurred at an annual rate of 2.3%; agriculture, residential areas and timber plantations increased at annual rates of 0.3%, 0.85% and 1.6%, respectively, during the 1978-2008 period. Total forest and shrubland loss rates were partly offset by passive revegetation following the institution of community forestry in the 2000s. However, most of the areas that were passively revegetated remained as shrubland and did not turn into forests due to a low capacity of forest recovery. This resulted in a progressive loss and degradation of forest and water resources over the entire region. Overall, the documented land cover changes increase provisioning services such as crops, cattle, and timber that are characteristic of cultural landscapes in the area but may cause an irreversible loss of biodiversity and a depletion of other ecological services provided by forests and shrubland. The implications for conservation of this area and the need for territorial planning and adapted land"=use strategies are discussed.
Keywords: Ecosystem services, deforestation, Kilum/Ijim Mountains, remote sensing, savannah watersheds