The development of land quality indicators for soil degradation by water erosion

The paper describes a proposed methodology for estimating water erosion risk for large areas. The estimates are based on a one-dimensional hydrological balance and a physically based sediment transport model. Estimates of risk associated with a given storm amount are integrated over the frequency distribution of daily rainfalls to provide a properly weighted estimate of the average annual risk. Soil factors are estimated from textural classes using qualitative pedo-transfer functions. Climatic data are taken from interpolated gridded data. Topographic data are taken from global or local DEMs. The estimates are for sediment delivery to stream channels. The method has been applied to provide a preliminary estimate for France at a resolution of 250 m, and could be applied globally at a resolution of 1 km. © 2000 Published by Elsevier Science B.V.