近年来珠江流域水位-流量演变与成因分析

Analysis on Changes in Water Level-Flow of the Pearl River Basin in Recent Years and Its Causes

针对近年来气候变化与快速城市化对珠江流域水文情势的影响,分析了1997—2013年珠江流域16个主要水文站点的水位、流量及水位-流量关系的演变趋势与变异特征,并结合历史时期气象、水利工程与水沙数据,探讨了各个子流域水位与流量演变的成因。结果表明:①珠江流域大部分站点年平均流量并无显著变化,但西江流域江边街、涌尾、柳州等站均呈现显著的减少趋势;②在汛期绝大部分站点的流量呈减少趋势,在枯水期大部分站点的流量呈增加趋势,降水在汛枯期的不同变化趋势是导致流量变化的重要因素;③西江流域大部分站点水位呈显著升高趋势,持续加剧的水土流失是其重要成因,而北江流域与东江下游在水库运行与采砂活动的影响下呈现出河床下切、水位下降的趋势。

Aiming at the impact of climate change and rapid urbanization on the hydrological situation in the Pearl River Basin in recent years,this paper analyzes the evolution trend and variation characteristics of the water level,flow and water level-flow of 16 major hydrological stations in the Pearl River Basin from 1997 to 2013,and discusses the causes of the evolution of water level and flow in each sub-basin based on the meteorological,hydraulic engineering,and water and sediment data in the historical period.The results show that:①The average annual flow of most stations in the Pearl River Basin didn t change significantly,but the Jiangbianjie,Chongwei and Liuzhou stations in the Xijiang River Basin showed a significant reduction trend;②The flow of most stations in the flood season decreased,while that in the dry season increased.The different precipitation during the dry/flood season was the important factors leading to the change of flow in the Pearl River Basin;③The water level of most stations in the Xijiang River Basin showed a significant upward trend,which was caused by the aggravating water and soil loss.While under the influence of reservoir operation and sand mining activities,the Beijiang River Basin and the lower reaches of the Dongjiang River Basin showed a trend of riverbed down-cutting and water level lowering.