南水北调中线水源区(陕南段)水土保持效益分析

Analysis of Soil and Water Conservation Benefits in the Water Supply Area(Southern Shaanxi) of the Middle-Route of the South-to-North Water Diversion Project

依据2007—2010年的统计与调查资料,在对典型流域进行调查的基础上,采用有无水土保持项目对比法,对南水北调中线水源区陕南安康、商洛、汉中三市水土保持措施及其效益进行了分析。结果表明:治理后与治理前相比,各地类拦蓄径流量、保土效益明显增加,植被覆盖度增加,生态环境改善,当地居民生活水平也随之提高。不同措施对拦蓄径流的作用顺序依次为:封育措施>水土保持林草措施>坡面整治措施>能源替代措施>保土耕作措施;不同措施对保土效益的作用顺序依次为:水土保持林草措施>封育措施>坡面整治措施>能源替代措施>沟道防护措施>保土耕作措施。研究结果可为类似水源区的水土保持综合治理工作提供借鉴。

In this paper, the benefits of soil and water conservation measures of Ankang, Shangluo and Hanzhong were analyzed based on the statistics and typical watershed survey data from 2007 to 2010, during which the method of contrastive analysis was used. The research areas, which lie in the southern Shaanxi Province, belong to the the water supply area of the middle-route of the South-to-North Water Diversion Pro- ject. The results showed that impound runoff and soil conservation increased apparently compared with for- mer treatment, the ecological environment had been improved with the increase in vegetation coverage, the living standard of local people also increased. Effects of different measures on impound runoff were as follows： closing hillsideS〉vegetable measures〉slope harness measures〉alternative energy measures〉tillage measures; the order of the role of different measures on soil conservation are as the sequence of vegetable measures〉 closing hillside〉 slope harness measures〉alternative energy measures〉gully erosion control measures〉tillage measures. This study can provide useful guidance for comprehensive harness of soil and water loss in similar water supply area.