典型湖流对鄱阳湖出湖实测流量影响研究

The Influence of Typical Lake Current on the Outflow of Poyang Lake

鄱阳湖是我国最大的淡水湖泊,水情情势受入湖洪水和长江洪水共同影响,具有独特水文特征。本文以星子断面实测流量成果代表鄱阳湖出湖流量,探讨各典型湖流对出湖流量影响。得到结论如下:1)不同湖流形态下,影响出湖流量主要因素或各因素贡献度不同;2)重力流下,影响鄱阳湖出湖流量变化的主要因素是五河来水量,且出湖流量大小能够利用湖区水位高低来反映,且当星子水位与湖口水位落差大于等于0.10 m时,可通过入湖流量及星子水位来计算出湖流量;3)顶托流下,影响鄱阳湖出湖流量变化主要因素受长江水量级别不同而发生变化,当九江流量小于50,000 m3/s或大于60,000 m3/s时,出湖流量与大通站与九江站流量差值、入湖流量存在较好相关关系;4)倒灌流下,影响鄱阳湖出湖流量主因是长江来水量大小和鄱阳湖水位多少,倒灌期间九江流量变化累积效应能够很好的反映出湖流量累积效应的变化。

Poyang Lake is the largest freshwater lake in China,and its water situation is affected by both lake inflow flood and Yangtze river flood.In this paper,the measured discharge of Xingzi station is used to represent the outflow of Poyang Lake,and the influence of typical lake current on outflow is discussed.The conclusions are as follows:1)Under different lake current patterns,the main factors affecting the change of lake flow or the contribution degree of each factor is different.2)In gravity flow,the main factor affecting the change of the discharge of Poyang Lake is the inflow.When the fall between the water level of Xingzi Station and that of Hukou Station is greater than or equal to 0.10 m,the lake discharge can be calculated by the inflow and the water level of Xingzi Station.3)Under the condition of the water jacking of the Yangtze River,the main factors affecting the change of the discharge of Poyang Lake varies with the different water levels of the Yangtze River.When the discharge of Jiujiang station is less than 50,000 m3/s or more than 60,000 m3/s,there is a good correlation between the discharge difference between Datong Station and Jiujiang Station and the inflow into the lake.4)In the case of the backflow of the Yangtze River on Poyang Lake,the main factors affecting the outgoing flow of Poyang Lake are the amount of water coming from the Yangtze River and the level of Poyang Lake.There is a good relationship between the discharge accumulations of Jiujiang station and the lake discharge accumulations.