牛栏江上游水沙变异点分析及影响因素探讨

牛栏江上的德泽水库是引水改善滇池水环境的水源工程，因此，分析牛栏江的径流和泥沙含量变化对滇池水环境改善效果的影响，具有重要现实意义。以牛栏江上游的四营和七星桥水文站作为代表站，依据1956～2009年实测水文资料，分析了河流水沙的变化特性。分析结果表明：从1982年开始，牛栏江上游的径流量变化趋势与降雨量变化相反，即降雨增大，径流反而减小；1992年以来，流域产沙量明显减少。对引起水沙变异的主要因素进行了分析，发现人类的活动是牛栏江上游水沙变化的主要原因。

Research on aberrance point of flow and sediment in upper Niulan River and influential factors

Deze Reservoir in Niulan River is the water sources project for improving water environment of Dianchi Lake,so the analysis on the influence of flow and sediment variation of Niulan River is significant to assess the improvement effect of water environment of Dianchi Lake.Siying and Qixingqiao hydrological stations in the upper Niulan River are taken as the representations,by using the measured hydrological data from 1956 to 2009,the variation characteristics of river flow and sediment are analyzed.The analysis results show that from 1982,the variation trend of runoff in the upper Niulan River is in contrast with that of precipitation,namely,the precipitation increases,but the runoff decreases;since 1992,the sediment yielding amount in the basin decreases obviously.The analysis indicates that the human activities are the main cause of flow and sediment variation in the upper Niulan River.