基于水量平衡原理和Budyko假设的强人类活动干扰下西辽河流域径流衰减归因分析

Attribution analysis of runoff attenuation in the Xiliao River Basin under significant human interference based on water balance principle and Budyko hypothesis

针对Budyko假设在强人类活动干扰流域应用的不足,将其与水量平衡原理相结合,量化降水、潜在蒸散发、下垫面和人类用耗水变化对西辽河及其3大支流(老哈河、西拉木伦河和乌力吉木仁河)流域实测径流衰减的贡献。结果表明:1956—2020年西辽河流域径流以0.17亿m^(3)/a的速度显著衰减(p=0.005),并在1966年、1984年和2005年左右发生了3次突变,其间人类用耗水变化是西辽河流域径流衰减的主导因素,贡献率为77.4%,潜在蒸散发、下垫面和降水变化的贡献率分别为8.8%、7.9%、5.9%;1984—2020年,下垫面改变成为西辽河流域径流衰减的主导因素,贡献率为58.3%,其次是降水变化,贡献率为28.8%;1956—2020年各支流流域实测径流变化特征与主导因素差异较大,但整体以人类活动影响为绝对主导因素,贡献率在78.5%~91.7%之间。

To address the shortcomings of Budyko hypothesis in its application to river basins with significant human interference,Budyko hypothesis was combined with water balance principle to quantify the contributions of changes in precipitation,potential evapotranspiration,underlying surface,and human water consumption to the observed runoff attenuation in the Xiliao River Basin and its three major tributary basins(the Laoha River,Xilamulun River,and Wulijimuren River).The results showed that the observed runoff in the Xiliao River Basin significantly decreased at 17 million m^(3) per year(p=0.005)from 1956 to 2020,and underwent three abrupt changes around 1966,1984,and 2005.Change in human water consumption was the dominant factor contributing to the observed runoff attenuation in the Xiliao River Basin during this period,with a contribution rate of 77.4%,and the contribution rates of changes in potential evapotranspiration,underlying surface,and precipitation were 8.8%,7.9%,and 5.9%,respectively.Underlying surface change played a dominant role in runoff attenuation in the Xiliao River Basin from 1984 to 2020,with a contribution rate of 58.3%,followed by precipitation change,with a contribution rate of 28.8%.The change characteristics of observed runoff and the dominant factors in each tributary basin differed greatly,but human interference played a dominant role from 1956 to 2020,with the contribution rate ranging from 78.5%to 91.7%.