Assessing Soil Erosion Potential Using GIS for A Typical Watershed in East-Tiaoxi Basin, China

Using a Geographic Information System(GIS)and the Universal Soil Loss Equation(USLE), we assessed the soil erosion potentials for a typical watershed in East-Tiaoxi basin. The results showed that there existed positive correlation between soil erosion and rainfall intensity (r=0.730,P0.05). Rainfall erosion was the main form of soil erosion in the watershed. The annual average soil erosion modulus amount- ed to 2 347 t·km-2, which fall into the category of mild-degree erosion. Besides the rainfall, the vegetation cover was important factor causing soil erosion. The erosion in the watershed was generally stronger in southern and northern part than that in the central. In terms of land use/ cover categories, the annual average soil erosion intensity was in sequence:urbanruralcroplandforestorchard. It was also indicated that human activities had great influence on soil erosion. In addition, slope was correlated with soil erosion modulus. The middle and high intensi- ty of erosion were found in steep slope zone and the cropland with the slope ranged from 7° to 12°. The intensive and extremely intensive ero- sion were found in the cropland, urban land and rural land with slope greater than 12°.