Extraction of RUSLE-LS Factors Using DEM data and GIS Techniques

The assessment and prediction of soil erosion at regional scale is of great importance to the sustainable land use planning and ecological restoration.Yet reliable prediction of soil erosion depends on the factors affecting the soil erosion,just as described in RUSLE.As one of the important factors affecting the soil erosion,topographic factor may have impact on the soil erosion in many aspects such as the redistribution of rainfall and runoff accumulations and its velocity,and many studies have been done on it.However,most of studies just focused on the impact of topographic factor on soil erosion,only few studies have been done on the extraction of topographic factor,and little on the validation and comparison of topographic factors extracted.In this paper,the topographic factor(LS) for RUSLE(revised universal soil loss equation) using powerful DEM and GIS techniques was extracted for Xiannangou catchment,Loess plateau,aiming at providing technological support for the assessment and prediction of soil erosion on regional scale.The results showed that the LS values extracted from the fine DEM with a resolution of 5?m,if choosing a right algorithm,are reasonable,reliable and practicable.It can provide a reference for the further study of LS factors on regional scale and providing a basic data for scale transform among different scales.