泾河流域水土保持措施减水减沙作用分析

采用“水保法”对泾河流域自70年代以来水土保持保持的减水减沙作用进行了分析研究。在研究过程中,根据泾河流域各县1989年土地详查资料和1996年土地变更调查资料,核实了泾河流域水土保持措施的保存面积。坡面措施减洪减沙作用计算方法自成体系,在小区坡面措施减洪指标推到流域的过程中,消除了小区与流域存在的时段、点面和地区三方面差异;流域坡面措施减少量的计算注重了坡面与沟道、洪水与泥沙的有机联系。计算结果表明：1970－1996年,泾河流域年均综合减水6.537亿m^3、减沙0.475亿t。

Analysis of Water and Sediment Reduction Effects by Soil and Water Conservation Treatments in Jing River Basin

The effect of water and sediment reduction by soil and water conservation treatments in Jing River basin since 1970s has been analyzed and studied in the paper by using "soil conservation method". During the study, the preserving area of soil and water conservation treatments in the basin was checked and verified according to the land investigation data in 1989 and land change data in 1996. There is a independent calculation method for effect of flood and sediment reduction effects by slope soil conservation measures: the differences among time, point to watershed and locations between experimental plot and watershed has been eliminated in the process of extending the plot indices of flood reduction to whole watershed. Attention has been paid on the organic link between slope and gully, flood and sediment in the calculation of sediment reduction by slope conservation measures. The results show that the average annual comprehensive water reduction in Jing River basin is 6.537 billions m 3 and sediment reduction 47.5 million tons from 1970 to 1996.