平江流域水土保持综合治理水沙调配效益评价

以位于南方典型水土流失区的平江流域为研究对象，以长序列历史观测数据为基础，应用径流调控理论，对流域水土保持综合治理措施体系水沙调配效益进行了定性和定量的对比分析，结果表明：通过30多年的水土保持综合治理，平江流域径流洪枯比由治理前1958~1979年的年均3.51下降到治理后1980~2015年的年均2.45，枯季径流量占全年径流总量的比例总体呈上升趋势；流域年输沙量呈显著下降趋势，年均减少1.48豫，尤其是治理后期的2003~2015年，流域年均输沙量比治理前下降了61.4豫.体现了流域水土保持综合治理调控径流时空分配及减沙效益显著.

Benefit evaluation of the runoff and sediment distribution in soil and water comprehensive management of Pingjiang watershed

The study area of this paper was located in the Pingjiang watershed,the typical soil erosion area of Southern Chi-na. Qualitative and quantitative benefits comparative analyses of soil and water comprehensive management were made based on the long series of historical observational data and runoff distribution theory. The results shown the ratio of runoff between flood and dry season decreased significantly from 3 . 51( years from 1958 ~1979 )to 2 . 45( years from 1980 ~2015 ),the proportion of dry season runoff volume to yearly total runoff volume continuously increased after 30-years soil and water comprehensive management in Pingjiang watershed. The watershed sediment transportation decreased by 1. 48%per year,especially during the later period from 2003 to 2015,61. 4% of the eroded sediment was trapped in the watershed compared with the value of period before management. The watershed soil and water comprehensive management show a sig-nificant positive effect in runoff distribution and sediment trapping.