Study on Soil Erosion of Different Vegetation Regions in Loess Plateau Based on GIS

The spatial data of vegetation regions and soil erosion in loess plateau were spatially overlap-analyzed with geographical information system(GIS)technology and landscape ecological methods on the basis of loess plateau vegetation regions classification.For a long time,severe soil erosion has not only produced a great impact on agriculture in this area,but also seriously damaged the ecological system of the Loess Plateau and the near areas.The study shows the crucial factor leading to soil erosion was vegetation.The vegetation region attributes in Loess Plateau were embodied with geographical information system(GIS)technology,two-way indicator species analysis(TWINSPAN)and detrended canonical correspondence analysis(DCCA).The Loess Plateau is classified into four regions,which are forest vegetation region,forest-steppe vegetation region,steppe vegetation region and semi-desert and desert vegetation region.There existed a close relation between the vegetation region and soil erosion in Loess Plateau land-scale.The relationship of the vegetation region and soil erosion in Loess Plateau was discussed by using the spatial overlap statistics of the soil erosion data and vegetation region data based on geographical information system.The results showed that frozen erosion distributes in both forest-steppe vegetation region and steppe vegetation region while water erosion,wind erosion and water-wind erosion distribute in all vegetation regions.In forest vegetation region,water erosion above the light degree accounted for 41.92%,and water erosion index,being 346.90,was bigger than those in the steppe vegetation region and semi-desert and desert vegetation region.In forest-steppe vegetation region,water erosion above the light degree accounted for 70.45%,and water erosion index,being 449.40,was biggest in all the indexes of the vegetation regions,which meant water erosion in the forest-steppe vegetation region was the most severe.In steppe vegetation region,water-wind erosion was main,accounting for 33.01%,and water-wind erosion index,being 633.45,was biggest in all the indexes of the vegetation regions,which meant water-wind erosion in the steppe vegetation region was the most severe.In semi-desert and desert vegetation region,wind erosion above the light degree accounted for 99.65%,and wind erosion index,being 589.78,was bigger than any other index in the rest vegetation regions,which meant wind erosion in the semi-desert and desert vegetation re-gion was the most severe.The distribution of soil erosion in loess plateau was obviously characterized by spatial change,and such results can demonstrate the effectiveness of studying the relationships of the vegetation region and soil erosion with geographical information system and landscape ecological method and provide scientific evidences for the protection,utilization,recovery and reconstruction of Loess Plateau.