Soil degradation and nutrient depletion have become serious threats to agricultural productivity in Africa. Soils cannot supply the quantities of nutrients required and yield levels decline rapidly once cropping commences. This book addresses these issues and includes papers from an international symposium held at Cotonou, Benin, October 9-12, 2000, organized by the International Institute of Tropical Agriculture, Ibadan, Nigeria and the Department of Land Management of the Katholieke Universiteit Leuven, Belgium. In five main parts, it marks the end of a first phase of collaborative research...