Mapping Topsoil Texture in the Arid And Semiarid Region of Asia using Remote Sensing Data

In the present research, we will demonstrate the potential of mapping topsoil texture in arid and semiarid Asia by a topsoil grain size index (GSI) using MODIS data. The 1-km resolution BRDF rectified MODIS reflectance data at the end of April in 2004 is used for producing the soil grain size distribution or GSI map. Result shows that high GSI area distributed at the desert and its' marginal area, degraded grassland, desert steppe. The degradation map was output according to the correlation between GSI and grain size percentage composition, the degree of degradation was classified into 4 levels as no, light, middle, and severe. The result can manifest the soil degradation well.