水府庙水库流域土壤保持功能生态价值评估

Spatial Distribution Characteristics and Eco-economic Value of Soil Conservation Service in Shuifumiao Reservoir Watershed

在GIS和RS的支持下,基于改进的通用土壤流失方程(RUSLE)、影子价格法、机会成本法和替代工程法,以水府庙水库流域为研究对象,对该区域的土壤保持功能及价值的空间分布特征进行分析。研究表明,水府庙水库流域生态系统土壤保持总量为1.69×106t;生态总价值为91 829.72万元,其中生态系统土壤减少养分损失的价值为65 403.65万元、因防止土壤侵蚀而减少废弃地的价值为5 670.38万元、减轻泥沙淤积灾害方面的价值为20 755.69万元;土壤保持功能及其价值在空间上表现出很大的差异性,从流域中部地区向四周递增;土壤保持功能价值与植被覆盖度相关性较强,合理增加植被盖度对防治土壤侵蚀和增加土壤保持功能价值可以起到良好效果。

GIS and RS technique, and RUSLE are selected to calculate the amount of soil erosion. Here we explore spatial distribution characteristics of the ecosystem＇s soil conservation and evaluated its eco-economic value with a case study in Shuifumiao Reservoir Watershed, China. Results show that the total amount of soil conservation is 1.69x106 t, and the total eco-value is 9.18 billion yuan, in which value for soil ecological system to reduce nutrient loss is 6.5 billion yuan, value for preventing soil erosion and reducing the waste land is 0.56 billion yuan, and value for the reduction of sediment disaster is 2.07 billion yuan. The soil conservation function and value show significant differences in space, they are higher in the middle of the watershed. The value of soil conservation is likely higher if there are better vegetation coverage over watersheds, indicating that the increase of the vegetation covering had beneficial effects on the prevention and control of soil erosion and increasing soil conservation function value.