黄土丘陵沟壑区水土流失治理模式、治理成本及效益分析--以米脂县高西沟流域为例

Mode,cost and benefit of soil and water conservation on the Loess Plateau:A case study in Gaoxigou watershed in Mizhi County

通过黄土丘陵沟壑区水土流失治理典型——陕北米脂县高西沟的水土流失治理措施配置模式、治理成本和治理效益分析，认为水土流失治理措施配置模式应由治理目标所决定，不同治理目标指导下的治理模式将产生不同的生态效益和经济效益；针对水土保持效益的多重性、连动性、交叉性和互动性等特点，提出水土保持效益评价原则；依据该原则，估算以粮食自给为目标的治理模式，其投入治理成本是65.70万元/km^2，5-6年内可收回成本；此时治理流域基本达到泥不下坡，水不出沟，林草覆盖率达到40%-50%，粮食自给，年经济收入3 000元/人左右的生态和经济效益。治理区虽全面治理达标，但经济收益仍远低于全国平均水平，单纯依靠水土保持难以达到全面小康，这是值得有关部门应深思的问题。

Based on the analysis of mode, cost and benefit of collocation of soil and water loss control measures in Gaoxigou of Mizhi County in the North of Shaanxi Province, which is the typical examples of soil and water loss control in the hilly-gullied Loess Plateau, it＇s regarded that collocation mode of soil and water loss control measures should be decided by the goal of soil and water conservation, and the ecological benefit and economy benefit are different under control modes which are instructed by different goals. According to multiple, coherent-dynamic, intercrossing and mutual-dynamic characteristics of soil and water conservation benefit, assessment principle of soil and water conservation benefit is put forwarded. According to the assessment principle, the cost of control mode under the goal of food self-support is 657 000 yuan/km^2, and the cost could be took back in about 5 - 6 years; at this moment, no sediment come form slope and no water flow out of gully, vegetation cover reach to 40% - 50%, food self-supply, and annual income is 3 000 Yuan per capita. However, even after reaching to the goal of comprehensive control, the economical income is far below the countrywide average level, it＇s hard to entirely achieve well-off level only depending on soil and water conservation, and this is a thoughtful question to related institutions.