径潮动力对长江河口滞流点的影响  

Influence of change in river discharge and tides on stagnation points in the Yangtze River estuary

作　　者：黄李冰[1] 李义天[1] 韩剑桥[1] 孙昭华[1] 杨云平[1] 

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072

出　　处：《水科学进展》2015年第4期572-578,共7页Advances in Water Science

基　　金：国家重点基础研究发展计划(973计划)资助项目(2010CB429002)~~

摘　　要：为研究三峡蓄水后滞流点的时空变化规律,应用ECOMSED模型模拟长江河口在不同径流、潮流作用下的水流动态过程。结果表明:北支大洪水期下移幅度大,涨潮动力强劲,随潮流变化大;南侧变化幅度整体较北支小,随径流的变化幅度自大至小依次为北港、南槽、北槽;随潮流的变化幅度自大至小依次为南槽、北港、北槽。滞流点随径、潮条件变化时,受地形影响明显,三峡蓄水后,径流变化范围缩小,引起不同地貌单元滞流点范围不同程度的缩小,可据此认为,与滞流点位置一致的最大浑浊带范围呈现减小的趋势,由此可能引起最大浑浊带和地貌调整。Variations in long-term river discharge and tides caused by upstream structures can have a significant influ- ence on estuarine geomorphological features. We used the ECOMSED model to simulate dynamic flow processes for a range of river discharges and tides in the Yangtze River estuary so that we could determine the influence of the Three Gorges Project （TGP） impoundment on stagnation points in the estuary. The results show that, as a result of changes in flows and tides, there were obvious spatial and temporal variations in the extent of major stagnation points in differ- ent parts of the estuary. The model demonstrated that there was significant movement in the stagnation points in the North Branch during flood periods. Because of the strong force of the rising tide, the stagnation points changed dramat- ically with changes in tides. Overall, the ranges of the variations in the South Branch channels were less than those in the North Branch channels. The range of the variations because of changes in river discharge decreased in the order： North Channel〉 South Passage〉 North Passage. The range of the variations because of changes in tides decreased in the order： South Passage〉 North Channel〉 North Passage. Results confirm that the geomorphological conditions are important for the stagnation points. Since the TGP impoundment, the decrease in the range of river discharge has re- suited in a decrease in the extent of the stagnation points in all channels, which indicates that the area of the Turbidity Maximum Zone （TMZ） is decreasing. The TGP impoundment has therefore resulted in changes in the TMZ and related topographic features.

关 键 词：长江河口 滞流点 径流 潮流 对比分析 变化趋势 

分 类 号：TV148.3[水利工程—水力学及河流动力学]