Spatial distribution of soil erosion risk in red eroded area of South China

As an ecological process, soil erosion which endangers human existence and development has been one of environmental problem around the world for a long time. Affected by various environmental factors, soil erosion risk has obvious spatial distributions. Taked the Zhu River small watershed of red eroded area of South China as an example, selected the five risk factors of rainfall erosion, terrain slope, soil type, vegetation cover and land use, used spatial analysis and geo-statistics methods of ArcGIS, studied the soil erosion risk. The results indicate that: moderate risk, high risk and extreme risk area proportion accounted for 63.82% of the whole watershed. Light and moderate risk area is mainly distributed along the river valley, throughout the steep and acute slopes of the hilly. High risk area mainly distributed in thin woodland around the red reservoir, the transportation land, blut mountain, collapse post. Extreme risk area is distributed in the quarry. Soil erosion risk has anisotropic characteristics, including the direction of risk is the NE-SW and NEE-SWW, direction of high risk and extreme risk is E-W and SE-NW. The risk of soil erosion escalates gradually from west to east, and emerges “U” from north to south.