长江口整治工程对分水分沙年际变化的影响分析

Analysis on annual variation of diversion ratio of flow and sediment in Yangtze River Estuary after regulation project

为了研究长江口深水航道整治工程对水文泥沙过程的影响规律,基于1998～2009年长江口南北港、南北槽的水沙测验资料,分析了整治工程引起的南北港、南北槽分流分沙变化。结果表明,整治工程的实施对南北港涨落潮分流分沙比、净泄潮量及净泄沙量影响不大。一期工程的实施后,北槽落潮分流、分沙比减小,南槽落潮分流、分沙比增加;二期工程实施中,南北槽的落潮分流、分沙比均保持在较为稳定的状态;随着三期工程的实施完毕,南槽的落潮分流、分沙比持续增加,北槽的落潮分流、分沙比呈减小的趋势。

In order to study the influences of deepwater channel regulation project at Yangtze River Estuary on the hydrological and sedimentation process, the characteristics of diversion ratio of flow and sediment in different years are analyzed based on the measured data of water and sediment discharge in the south and north channels from 1998 to 2009. The results show that there is a little influence on diversion ratio of flow and sediment, net tidal discharge amount and net sediment discharge amount of Nangang and Beigang channels. After implementation of the phase I project, the diversion ratio of flow and sediment during ebb tide decreases in the north channel, while increases in the south channel; in the phase II project, the diversion ratio of flow and sediment in south and north channel during ebb tide remains stable. Due to construction of the phase Ill project, the diversion ratios of flow and sediment during ebb tide keep decreasing in the north channel, while increasing in the south channel.