The productivity and sustainability of Africa's environment is heavily dependent on how this asset is managed. This, in turn, can affect the availability, stocks and functioning of the remaining assets, either enhancing opportunities or putting livelihoods at risk. The range of livelihoods, with its opportunities for human development and alleviating extreme poverty and hunger, extends from total dependence on natural resource systems either for subsistence or as part of business, to total dependence on wage earnings, from trade or industry. National and local aspirations for sustainable development are linked to the integrity of natural resources and the environment. It is, therefore, critical to conserve and sustainably use the region's environmental assets, not only from an environmental perspective but also as a sustainable resource to support human well-being and development and as a sink for wastes from production processes. Over 70 per cent of Africa's population is rural and depends directly on the land and the natural environment for its livelihoods and well-being (IFAD 2001). Thus, how environmental goods-and-services are used will have practical consequences for alleviating poverty, improving human well-being, and ensuring sustained economic development.