鄱阳湖重金属Cu的运动足迹研究

选取我国典型的通江湖泊--鄱阳湖作为研究区域，采用MIKE21水动力模型耦合粒子追踪模型，模拟在重力型、顶托型、倒灌型3种不同湖流形态下鄱阳湖中重金属Cu的运动足迹.结果显示：（1）1月（重力型），长江下游处重金属运动速率最快，为2.111km/d，粒子一直沿着由北向南的方向运动至湖区中心的西北方向，之后突然改变运动方向；5月（顶托型），长江上游处重金属运动速率最大，达到2.901km/d；8月（倒灌型），与顶托型类似，长江上游处重金属运动速率最快，为3.287km/d.（2）从各支流重金属整体的运动情况来看，鄱阳湖水位受到五河来水及长江倒灌的影响，各点源重金属在湖区的运动足迹受顶托型和倒灌型湖流形态作用的影响较大，长江上、下游处重金属在不同湖流的影响下流速均较大，受湖流形态影响最小的是抚河的2个支流，粒子运动速率表现为：倒灌型 > 顶托型 > 重力型.

Study on the movement footprint of heavy metal copper in Poyang Lake

In this paper, the typical lake of river-connected lake in China, Poyang Lake, is selected as the research area. The MIKE21hydrodynamic model coupled with particle tracing model is used to simulate the movement footprint of heavy metal Cu in Poyang Lake under three different flow patterns of gravity type, top support type and inverted irrigation type. The simulation results showed that:(1) In January (gravity type), the heavy metal movement rate in the lower reaches of the Yangtze River was the fastest, at 2.111km/d. The particles moved along the north-south direction to the northwest direction of the center of the lake area, and then suddenly change its direction of movement. In May (top support type), the rate of heavy metal movement in the upper reaches of the Yangtze River was the highest, reaching 2.901km/d. In August (inverted type), similar to the top support type, the heavy metal movement rate in the upper reaches of the Yangtze River was the fastest, 3.287km/d. (2) Judging from the overall movement of heavy metals in each tributary, the water level of Poyang Lake was affected by the water from the five rivers and the backwater of the Yangtze River. The movement footprint of heavy metals in different point sources in the lake area was greatly affected by the shape of the top-supporting type and the inverted-flow type. The flow of heavy metals in the upper and lower reaches of the Yangtze River was relatively large under the influence of different lakes. The two tributaries of Fu River were the least affected by the shape of the lake. The particle motion rate was as follows:inverted type > top support type > gravity type.