长江口澄通河段河势演变分析*

根据1977-2006年间长江口澄通河段实测水下地形资料,从纵向变化、横向变化以及冲淤变化3个方面分析了澄通河段近期河势演变的特征并探讨了其对-12.5 m深槽变化的影响.分析表明:澄通河段内众多沙洲变化较为频繁,其中福姜沙、如皋沙群以及通州沙平面位置的摆动以及狼山沙沙体的不断向西移动对部分河段-12.5 m深槽的稳定和贯通带来了一些不利影响；另外,受上游来沙量减少的影响,整个河段的河槽容积有增大的趋势,这需要在以后的河势演变分析中加以深入研究.

Analysis of riverbed evolution of Chengtong reach at Yangtze Estuary

This paper analyzes the riverbed evolution of Chengtong reach at the Yangtze Estuary based on the measured bathymetry between 1977 and 2006, discusses the river regime evolution of Chengtong reach and the its influence on the variation of the -12.5 m deep channel from the riverbed changes in the longitudinal, lateral and vertical directions as well as the erosion and deposition change. The results show that frequent swings of local shoals in the Chengtong reach, such as Fujiangsha, Rugaoshaqun, Tongzhousha and the continuously west moving Langshansha have negative effects on the evolution of the local -12.5 m deep channel, i.e., causing some swings and even breaks. In addition, the reduced volume of sediment source due to the large-scale hydraulic engineering at upstream may cause the tendency of the increasing channel-fill volume, which is required to be further investigated in the future study.