Use of Argon, Corona, and Landsat imagery to assess 30 years of land resource changes in west-central Senegal

Over the past 35 years, an agricultural area of west-central Senegal has ex perienced rapid population growth, fast expansion of agricultural lands, a decline in rainfall, and degradation of vegetative and soil resources. Alth ough such changes have not escaped the attention of Senegal's people, its g overnment, and the scientific community, the ability to monitor and quantif y land resource trends of recent decades has been difficult. Recently avail able high-resolution satellite photographs from the American Argon and Coro na Programs provide coverage of Senegal back to 1963. The photographs make it possible to study and map land resources at the beginning of the Space A ge. In this study, we characterize the changes that have occurred in the re gion from the early 1960s to the mid-1990s. Early Argon and Corona photogra phs are used to reconstruct the historical land use and land cover: compari sons are made with assessments from recent Landsat images. Field studies an d aerial surveys provide additional insight. The forces of change, driven p rimarily by population growth and unsustainable agricultural practices, are examined.