A GIS-based Modeling Approach for Regional Scale Soil Loss Assessment on the Whole Loess Plateau of China

摘要

The Loess Plateau of China is well-known worldwide for serious soil erosion phenomenon starting from the loess deposit at large since the Quaternary. Now, the soil erosion researches available are focused on slope scale or small watershed scale, and the regional scale soil erosion study, which targets the regional soil erosion regulations as a whole coupled with a geo-integration idea, standard methodology and even real time monitoring-processing-assessment is inadequate so far. In this paper, the whole Loess Plateau is categorized into 3380 fundamental units for assessing (or map units) according to the erosion characteristics such as precipitation contours, soil properties and landform by expertise knowledge; a GIS platform software, ARC/INFO~®, is used to integrate all kinds of data necessary for the assessment; then, a statistic regional scale soil loss model is set up, which included five simple parameters appropriate for GIS processing; finally, the model is applied to assess the soil erosion of some typical areas as a case study on the plateau, and the results show that the model is acceptable to calculating the regional soil erosion of the plateau in a quick way.