The restoration of vegetation in the abandoned land requires support of water resources, but as drought events occur frequently in Southern China, especially significant in purple hilly region of central Hunan the restoration is often difficult. As a result, the vegetation is rare in purple hilly region and the eco-environment is very fragile, and soil degradation and erosion are very severely. Since 1990s, more and more dry-land in the hilly region was abandoned by the farmers because of the enlarging gap between the prices of farm products and manufactured products. After dry-land was abando...
