三峡水库运行对鄱阳湖江湖水文情势的影响

Influence of Three Gorges Reservoir operation on hydrological regime of Poyang Lake

三峡水库运行改变了长江中下游干流及通江湖泊的水文情势,基于实测水文资料,构建了反映长江中游复杂江湖关系的一、二维水动力数学模型,定量评估了三峡水库2009~2014年实际运行对长江与鄱阳湖江湖水文过程的影响程度。结果表明:三峡水库运行对湖口站5~10月水量交换过程影响相对较大,7~10月倒灌水量有所减少;三峡水库蓄水期长江中游干流流量减少,尤以10月最为显著,湖口站平均水位降低1.09 m,降低湖区水位效应可影响至康山;补水期长江中游干流1~3月流量增加明显,湖口站平均水位升高0.28~0.56 m,抬高湖区水位作用仅能影响到都昌附近;汛期湖口站5~6月最高水位最大抬高0.34 m,7~8月最高水位降低。研究成果可为鄱阳湖区综合治理与保护提供参考依据。

The hydrological regime of the mainstream in the middle and lower reaches of the Yangtze River and the lakes connected to the Yangtze River have been changed remarkably by the operation of the Three Gorges Reservoir.The impacts of the Three Gorges Reservoir operation on the hydrological process of the Yangtze River and Poyang Lake from 2009 to 2014 were evaluated based on one and two-dimensional hydrodynamic models and the observed hydrological data.The operation of the Three Gorges Reservoir had a relatively large impact on the water exchange process from May to October in Hukou Station,and back flow was decreased from July to October.The flow of the mainstream in the middle reaches of the Yangtze River was reduced during the water storage period of the Three Gorges Reservoir,especially in October,and the average water level of Hukou Station was decreased by 1.09 m.The maximum influenced reach can extend to Kangshan in the water storage period.During the water replenishment period,the flow of the mainstream in the middle reaches of the Yangtze River increased significantly from January to March,and the average water level at Hukou station increased by 0.28~0.56 m.The maximum influenced reach can only extend to Duchang.In the flood season,the highest water level at Hukou Station raised 0.34 m from May to June,and decreased from July to August.The research results can provide reference for the comprehensive management and protection of Poyang Lake.