大沽河流域水文情势变化研究

Study on Hydrological Regime Alteration of Dagu River Basin

[目的]探究大沽河流域长时间序列下径流的变化趋势和周期特征,为大沽河流域的水资源管理和可持续发展提供理论参考。[方法]基于大沽河流域南村水文站1956—2020年和闸子水文站1956—2016年的实测径流资料,采用Mann-Kendall检验法、滑动t检验法分析多年径流量变化趋势和突变时间,采用Morlet连续复小波法分析了流域多年径流量的周期特征。[结果]大沽河流域多年径流量整体呈下降趋势,且呈现出汛期(6—9月)流量多、非汛期流量少的特点,流量峰值一般出现在8月。南村站径流于1976年发生突变,闸子站径流于1979年发生突变。大沽河流域径流量在多个时间尺度下均出现明显的周期变化,第一主周期在20 a左右,且在20世纪80年代之前周期震荡显著。[结论]大沽河流域长时间序列径流量呈现出显著下降的变化趋势,流域径流量在20世纪70年代发生突变,且存在不同时间尺度周期变化的特征,未来应加强径流变化机理研究。

[Objective]The purposes of this study are to elucidate the long-term trends and periodic characteristics of runoff in the Dagu River Basin,and to offer the theoretical insights to guide water resource management and promote sustainable development in the Dagu River Basin.[Methods]The measured runoff data from the Nancun Hydrological Station(1956—2020)and the Zhazi Hydrological Station(1956—2016)were used to analyze the trend of annual runoff changes and abrupt change times using the Mann-Kendall test and sliding t-test.The Morlet continuous complex wavelet method was used to analyze the periodic characteristics of multi-year runoff in the basin.[Results]The annual runoff in the Dagu River Basin was generally declining,and there was a characteristic of more flow during the flood season(June—September)and less flow during the non-flood season.The peak flow usually occurred in August.The runoff of Nancun Station was abrupt in 1976,and the runoff of Zhazi station was abrupt in 1979.The runoff of the Dagu River Basin exhibited significant periodic variations at multiple time scales,with a dominant period of around 20 years,and significant oscillations before the 1980s.[Conclusion]The long-term series runoff of Dagu River Basin showed a trend of significant decline,and the basin runoff suddenly changed in the 1970s,and there were periodic changes in different time scales.In the future,the research on the mechanism of runoff change should be strengthened.