Abstract: Even for simple empirical model,it is difficult to obtain enough basic data of soil erosion. Establishing a simpler model for soil erosion amount estimation is necessary. Land use types,surface slopes,and vegetation coverage in Maojiaowan small watershed in Chishuihe River Basin were surveyed,and the soil erosion amount was estimated according to the method in Standards for Classification and Gradation of Soil Erosion. In order to accurately estimate the soil erosion modulus in the karst regions of Southwest China,the standards for gradation of hydraulic erosion in Standards for Classification and Gradation of Soil Erosion were revised. Additionally,it is necessary to use more accurate methods to measure vegetation coverage. It’s also pointed out that the soil erosion spatial distribution was controlled by landform in the karst regions of Southwest China,and it is necessary to conduct further study on the spatial distribution patterns of soil erosion to reveal the effect of landform on soil erosion.

Key words: gradation of soil erosion , small watersheds , soil erosion amount , Chishuihe River Basin , Three Gorges Project