visit the following link to get full text http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2028.2008.01042.x/abstractSustainable use of natural resources is an important aspect of ecosystems management. Sustainable management requires the maintenance of biodiversity and other vital ecosystem functions and processes, including provision of a myriad of ecological goods and services, such as cycling of nutrients and water. Resource management also needs social mechanisms that receive, interpret and process feedback signals from the ecosystems in adaptive ways. To ensure sustainable ecosystem management, it is important to have current state of knowledge related to ecosystem services so as to facilitate a critical evaluation of the consequences of ecosystem changes on human well-being and risks that could be associated with unsustainable ecosystem management. Many ecosystems, particularly in Africa, have undergone tremendous changes, associated with a number of drivers of bio-physical and socio-economic nature. The bio-physical drivers can be associated with global change or changes in the landscapes due to geomorphic processes, which can be triggered by, among others, tectonics forces. Socio-economic drivers are factors that enhance some of the bio-physical processes such as vegetation degradation, soil erosion and overexploitation of resources. Among the socio-economic drivers are microeconomic policy changes and rapid increase in population leading to increased demand on basic needs for subsistence, which in many African countries depend on natural resources.