基于长江河口水动力和盐水入侵三维数值模式ECOM-si，通过数值模拟分析长江河口水位上升对径流、潮流和风生流的影响，以及在多种动力因子综合作用下对流场和盐水入侵的影响. 数值实验结果表明，在长江河口水位上升30 cm 的情况下，各河道横截面面积增大，向海的径流流速减小；潮流随水深增深略微增大；枯季北风作用产生的北港进、南港出的水平风生环流加强，在北支向陆的风生流有所加强. 水位上升后，北支盐水入侵增强；南支中段盐度变化不明显；北港、北槽盐水入侵随水位增加变化最为显著，小潮期间盐度增大值大于1，大潮期间增幅有所降低，北港北汊受水深增加盐水入侵变化最为强烈；南槽口门处滩地由于水位增加，非线性效应减弱，盐度不同程度的降低. 水位上升后南支水源地三个水库取水口盐度均有所上升，减少了可取水时间，不利于供水安全.
A semi-implicit estuarine, coastal, and ocean model (ECOM-si) was used to simulate and analyze the influence of a rise in water level on runoff, tidal and wind-driven currents, and on current and saltwater intrusion under the combined effects of various dynamic factors. In a scenario where the water level rises 30 cm in the Changjiang Estuary, numerical simulation results show that seaward runoff decreases due to augmentation of the river transection area; tidal currents decrease slightly with increases in water depth; the wind-driven current by northerly winds in the dry season is enhanced, which flow landward in the North Channel and seaward in the South Channel forming horizontal circulation; and the wind-driven current in the North Branch is strengthened. After the water level rise, saltwater intrusion in the North Branch is enhanced; salinity changes slightly in the middle reaches of the South Branch; the most distinct areas of saltwater intrusion enhancement are in the North Channel and North Passage, where the salinity rise is greater than 1 in neap tide and is somewhat reduced in spring tide; the salinity rise in the northern outlet of the North Channel reaches the maximum value observed in the entire estuary; and salinity on the shoal at the river mouth of the South Passage reduces because the water level rises and the nonlinear effect weakens. The water level rise, moreover, results in a salinity increase at the water intake of the three reservoirs (Qingcaosha, Chenhang, and Dongfengxisha) in the water source of the South Branch, which reduces water intake time and affects the safety of the water supply.
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中国综合性科技类核心期刊(北大核心)