GIS Modelling of Soil Loss from Semi-Arid Lands of Jordan.
要旨In an attempt to assess the impacts of changing land cover on soil, a GIS-based erosion model has been developed to predict annual soil loss by water in northern Jordan. This model uses the Revised Universal Soil Loss Equation (RUSLE). Spatially distributed static (topographic and soil) parameters for this model were extracted from a regional GIS. The dynamic (vegetation cover) parameter was estimated from the land cover maps, derived by digital processing of multi-resolution, multi temporal Landsat MSS (14. 9. 1972), and TM (28. 8. 1992). Mapping of vegetation cover was carried out by applying TM-Linear Mixture Modelling and NDVI, while mapping of fallow lands was carried out by both on-screen digitizing and sketch mapping in the field. The erosion model predicts an increase of 6.2% in the amount of soil loss in the study area from 1972 to 1992; as a result of changes in land cover especially vegetation cover.