Rehabilitation of a semiarid ecosystem in Senegal. 2. Farm-plot experiments

摘要: Abstract In the Sudano–Sahelian zone of western Africa, characterized by semi-extensive agriculture and subhumid climate, soil degradation water shortages are widespread features. Soil conservation practices introduced to farmers, but often abandoned thereafter. Some interesting results have been obtained, on a hillside scale, in southern part cropping basin Senegal. As supplement experimental design, two small watersheds (2.5 ha) were delineated equipped representative locations. 1988, both planned submitted an hydrological survey. One them, located colluvial/alluvial terrace, was also storage grain yield monitoring. Results highlight decisive effect relief features efficiency measures. Relevant obtained upstream areas still generated marked losses. These phenomena, addition socioeconomic constraints, partly explain farmers' behaviour noticed scale.