修河干流径流极值系列多时间尺度变异及成因

Research on Variation and Cause of the Multi-time-scale Extreme Runoff Series in the Mainstream of Xiuhe River Basin

在气候变化与人类活动的双重影响下,包括极端径流在内的水文要素常常表现出强烈的非一致性。以修河干流虬津站日径流系列为例,采用水文变异诊断系统对虬津站1956—2014年多时间尺度径流极值系列Max1d、Max3d、Max7d、Max15d和Max1m进行变异诊断分析,并从流域内降水、气温和水利工程建设等角度分析各时间尺度径流系列变异的原因。结果表明:①虬津站各时间尺度洪水极值系列分别在1981、1983、1983、1977、1977年发生显著的向下跳跃变异;②柘林水库蓄水运行对下游虬津站各时间尺度的径流极值系列变异均有显著影响;③研究区域内5月份降水量对虬津站各时间尺度极端径流系列变异有一定影响,月平均气温对区域内短历时尺度的径流Max1d和Max3d亦有显著影响。研究可为修河干流水旱灾害防治与水生态系统修复提供科学依据。

Nowadays,with the influence of climate change and human activities,many hydrological elements,including extreme runoff,usually suffer from strong inconsistency.Taking the daily runoff series of Qiujin Station on the mainstream of Xiuhe River as an example,this paper discusses the variation of multi-time-scale extreme runoff series,that is,continuous maximum 1 day series Max1d,continuous maximum 3 day series Max3d,continuous maximum 7 day series Max7d,continuous maximum 15 day series Max15d and continuous maximum 1 month series Max1m in Qiujin Hydrological Station from 1956 to 2014 through hydrological variation diagnosis system,and analyses the reasons for the variation of multi-time-scale runoff series from the perspectives of precipitation,temperature and water conservancy project construction in the basin.The results indicate that:①The above multi-time-scale runoff series all suffered downward jumping variation in 1981,1983,1983,1977 and 1977,respectively;②Zhelin reservoir has a significant effect on the variation of multi-time-scale extreme runoff series of Qiujin station;③The precipitation in May were the main meteorological factor affecting the variation of the multi-time-scale extreme runoff in Qiujin station,while the monthly average temperature also has a significant impact on the short-term runoff series of Max1d and Max3d.This research can provide scientific basis for the prevention and treatment of flood and drought disasters and the restoration of water ecosystem in the mainstream of Xiuhe River Basin.