Assessing environmental conditions of major river basins in Africa as surrogates for watershed health

There is a growing recognition of the importance of transboundary shared natural resources. However, with limited resources, international policymakers need to be able to prioritize regions before allocating resources and addressing transboundary problems. River basins are perhaps the most natural transboundary division and, as such, provide an ecological framework for environmental assessments. The health of watersheds that are divided by political boundaries are at particular risk due to differential land management practices within each watershed. In Africa, more than any other continent, over 60% of the geographical area is a transboundary watershed. In this article, a comparative study of the five major basins in Africa-the Congo, Chad, Nile, Niger, and Zambezi-has been carried out using consistent geospatial data sets at 1-km resolution. Population, land cover type, and protected areas were used to assess the current status, characteristic differences, and impending pressure on river basin resources for each watershed. In addition, a focused study within the Nile River basin is used to compare the particular differences between countries.