In order to quantitatively analyze and reveal the present spatial distribution of soil erosion sensitivity

identify key areas for the loss of water and soil in Leishan county which belongs to the key ecological function area

and provide theoretical basis for comprehensive prevention and control of soil and water loss and ecological environment

this study selected the ALOS images in Oct 2010

and 1:50 000 topographic map which covers the whole Leishan county as the data source. Through using the geospatial information technology (RS and GIS) combined with 3D analyst grid calculation function

Leishan County’s DEM

slope gradient

slope aspect

land use and other main factors were extracted. By using ENVI software

combined with the normalized difference vegetation index model

the vegetation coverage was extracted. The spatial overlay analysis in ArcMap was used to divide water and soil erosion sensitivity level

quantitatively analyze its sensitivity in present situation

and reveal its spatial distribution. The results showed that: the slightly and highly sensitive area of soil erosion was 812.29 km2

accounting for 67.45% of total area in Leishan country

and the sensitivity of soil erosion was mainly slight in most areas of the county. The highly sensitive area of soil erosion was small

accounting for 5.96% of the total area. At the same time

there was a significant relationship between different elevation

slope aspect

slope gradient

vegetation coverage level and the sensitivity of soil erosion in the study area. The slightly and highly sensitive soil erosion area appeared single peak distribution which increased at first then decreased. The sensitive soil erosion area occurred mainly in the altitude range of 800 to 1 400 m

with the southeast and the northwest slope and the slope degree of 15 to 35

and the vegetation coverage level in 30% to 45%.