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分析了河龙区间1997—2006年人类活动对减水减沙的贡献率,探讨了不同流域减沙效益与流域面积的尺度关系。结果表明:①河龙区间近期坡面措施减水减沙贡献率分别为30.2%和54.5%,淤地坝减水减沙贡献率分别为18.0%和27.8%,水利措施减水减沙贡献率分别为46.3%和20.9%,人为新增水土流失减水减沙贡献率分别为-1.8%和-9.7%,封禁治理减水减沙贡献率分别为1.1%和2.2%。②河龙区间近期水利措施减水贡献率最大且不同年代变化不大,坡面措施减沙贡献率最大且上升趋势明显,淤地坝减水减沙贡献率下降趋势明显。水保措施减沙贡献率普遍大于减水贡献率。近期河龙区间水土保持减水减沙的措施主体和构成发生重大变化,林地减水减沙贡献率最大。③随着流域尺度的增大,河龙区间水利水保综合治理的减沙效益呈减小趋势。
The contribution rate of human activities to water and sediment reduction in Heilong region from 1997 to 2006 was analyzed, and the relationship between the benefits of sediment reduction and drainage area in different watersheds was discussed. The results showed that: (1) the contribution rates of paddy and sediment reduction measures in the Helong range were 30.2% and 54.5% respectively, and the contribution rates of silt dam to water and sediment reduction were 18.0% and 27.8%, respectively Accounting for 46.3% and 20.9% respectively. The contributing rates of man-made water and sediment reduction were -1.8% and -9.7%, respectively, and the contribution rates of water supply and sediment reduction by blocking embankment were 1.1% and 2.2% respectively. ② The contribution rate of water conservancy measures in Helong range is the largest and has not changed much in different years. The contribution rate of sediment reduction by slope measures is the largest and the upward trend is obvious. The contribution rate of silt dam reducing water and sediment decrease obviously. The contributions of paddy-water conservation measures to sediment reduction are generally greater than the contribution rate of water-reducing measures. Recent Dragon River water and soil conservation measures to reduce sediment and the main changes in the composition of the major changes in the contribution of woodland water and sediment contribution to the maximum. (3) With the increase of watershed scale, the benefit of sediment reduction in integrated management of water conservancy and soil and water conservation in Heilong area tends to decrease.