Soil water balance in the Sudano-Sahelian zone: need, relevance and objectives of the workshop

The Sudano-Sahelian zoneextending over several countries in West Africa has an average growing season length varying hom 60 to 150 days Efficient use of the limited rainfall in this region is crucial as future increases in crop production will have to come primarily from increased yields per unit area of land. A complete understanding of the physical and hydraulic properties of the soils and of the different processes of soil water movement including infiltration, redistribution. drainage, evaporation and water uptake by plants is essential in the design of appropriate management practices for increasing water u x efficiency. The need and relevance of smdies on these aspects is discus~ed. The objectives and the format for the technical xssions of the workshop are also presented. Finally. the planning meeting at the end of the workshop is discussed wlth respect to the sharing of knowledge and experience of different disciplines and the training needs for future applications of soil watcr balam research in the Sudano-Sahelian zone.