SAHELIAN RANGELAND PRODUCTION IN RELATION TO RAINFALL ESTIMATES FROM METEOSAT

Satellite data are routinely used to monitor the growing season over the Sahelian zone of Africa. This study seeks to relate the vegetation indices and the rainfall estimates, both derived from meteorological satellites, to help monitor and predict the production of rangelands and marginal agricultural areas. Plant water use was calculated from a simple model which takes into account the timing and distribution of rainfall: over a three-year period, the response of the Normalised Difference Vegetation Index (NDVI) to this quantity was consistent and was spatially quantified for two calibration years. A predictive model for end-of-season accumulated NDVI was developed and validated for a test year.