孤山川流域水文特征变化及驱动因素

Change of hydrological features and driving factor in Gushanchuan Basin

研究流域水文特征的变化及驱动因素对流域水资源开发利用与保护,水土保持及生态环境的建设具有指导意义。以孤山川流域为研究区,利用Kendall秩序相关法分析1956-2009年流域降水、径流、泥沙等水文要素的演化趋势,采用小波变换法对系列的周期进行提取,利用有序聚类法分析径流和泥沙序列的变异点,并分析气候变化和人类活动对水沙的影响情况。结果表明:近54年来孤山川流域实测降水量没有显著变化,而年径流量和输沙量显著减少;年径流量和输沙量序列都存在5、14和28年左右的周期,且均在1979年和1996年发生突变。气候变化和人类活动对年径流量减少的贡献率在不同时段有不同的值,在人类活动对下垫面影响的过渡期,贡献率分别为72.2%和27.8%;90年代中期到21世纪初,它们的贡献率分别是27.8%和72.2%。本研究将为孤山川流域水资源开发利用及优化配置提供科学借鉴。

The study on change of hydrological features and its driving factors has guiding significance for development and utilization and protection of water resources,water and soil conservation and construction of ecological environment. Taking the Gushanchuan Basin as the research area,the paper analyzed the trend of the rainfall,runoff and sediment with Kendall method from 1956 to 2009,extracted its period with wavelet transformation,and find the change point of runoff and sediment series with the orderly cluster method,and finally analyzed the influence of climate change and human activities on runoff and sediment. The result shows that nearly 54 years,the precipitation in Gushanchuan Basin have no notable change,while the runoff and sediment reduced significantly; annual runoff and sediment discharge have the period of 5,14 and 28 years and mutated in 1979 and 1996. The contribution of climate change and human activities to the reduce of annual runoff have different values in different times,at the transitional period of human activities having influence on underlying surface,the contribution rates are 72. 2% and 27. 8% respectively. From the mid 1990 ’s to the beginning of 21 century,the contribution rates are 27. 8% and 72. 8% respectively. The result will provide a science reference for the development and utilization of water resources and optimal allocation.