三峡水库建库前后荆江低水水位流量关系分析

Analysis on water level-discharge relation of Jingjiang River during low water level period before and after impoundment of Three Gorges Reservoir

三峡水库蓄水运用以后,由于库区泥沙淤积,清水下泄,下游河道必然受到影响。通过对三峡水库建库前后荆江河段主要水文测站多年的实测资料对比,分析了水库建库前后荆江河段主要控制站宜昌、枝城、沙市、监利的断面面积及低水水位流量关系变化。分析结果表明,受水库蓄水后清水下泄影响,荆江河段尤其是枝城、沙市站断面下切较大,低水水位流量关系线下移,同流量级下水位降低;宜昌站由于前期受葛洲坝工程影响,断面已基本稳定,受三峡工程运行影响不大。

After impoundment of Three Gorges Reservoir,the sediment silting in the reservoir and clear water discharge significantly impact the downstream rive channel.Through comparison of multi-year hydrological data of Jingjiang River channel before and after impoundment of Three Gorges Reservoir,the variation of cross-sections and water level-discharge relations of the main hydrological stations（Yichang,Zhicheng,Shashi and Jianli） on Jingjiang River during low level period are analyzed.The analysis results show that under the influence of clear water discharge of Three Gorges Reservoir,the cross-sections of Zhicheng and Shashi stations incised greatly and water level-discharge relations are lowered,so the water level is lowered during low level period at the corresponding discharge;the cross-section of Yichang station is basically stable and influenced less by Three Gorges Reservoir because of the influence of Gezhouba Hydropower project constructed before Three Gorges Reservoir.