Characteristics and analysis of soil erosion in Li country after Wenchuan earthquake based on GIS and USLE

In order to more accurately evaluate soil erosion of Li country, Wenchuan earthquake-stricken area, Sichuan province, potential and actual soil erosion was qualitatively analyzed using the combination method of GIS, RS and USLE, and a brief comparison of soil erosion before and after earthquake was conducted. Moreover, changes of soil erosion area about different erosion intensity and the soil erosion amount were studied from four aspects, including slope, slope aspect, land use patterns and elevation. The results showed that soil erosion in Li country amounted to 844.46 million tons in the whole year and the average soil erosion was 1957.79 t/(km2·a), belonging to the moderate erosion. Compared with before earthquake, the areas of soil erosion were enlarged in mild, intensive and extreme regions especially at the region with slope more than 30-50 degree, altitude more than 2000-3000 m, as well as aspect of south and west slope. Further, the results provide a better basis for the reconstruction and the conservation of the soil erosion in Li country.