鄱阳湖水位变化对赣江尾闾河段分流比影响研究

赣江尾闾河段为典型的多级分汊河道,其分流比受诸多因素的影响。通过定床敏感性试验,分别探讨了在不同外洲流量工况下,鄱阳湖西支入湖水位、中支入湖水位、南支入湖水位动态变化和鄱阳湖水位整体变化对赣江尾闾各分汊河道分流比的影响规律。试验结果表明:随着西支、中支和南支入湖水位变化,赣江尾闾各支流分流比呈现出较好的线性变化规律,随着外洲流量的增大,其分流比随入湖水位变化率均呈现出幂函数递减的变化趋势;变动支流的入湖水位时,该支流分流比变化率最大,影响最明显;鄱阳湖水位整体变化时,赣江尾闾各支流分流比不会受到明显影响;东、西河分流比更易受南支入湖水位变化的影响。

Test study on effects of water level fluctuation of Poyang Lake on diversion ratio of estuaries of Ganjiang River

The Ganjiang River estuary reach is a typical multi-level branching channel, and its diversion ratio is affected by multiple factors. By conducting fix bed sensitivity tests under different flow conditions at Waizhou station (on the mainstream of Ganjiang River), the dynamic variations of water levels in the west lake-entering channel, middle lake-entering channel and south lake-entering channel and the water level of the Poyang Lake on diversion ratio of the Ganjiang River estuary are investigated.The test result indicates that with the water levels varied in the west,middle and south lake-entering channels, the diversion ratio of the Ganjiang River estuary follows a linear correlation. With the increase of the inflow at Waizhou station, the division ratio decreases in a power function with the variation of lake level. Diversion ratio of lake-entering channel is mostly affected by its corresponding level. When water level of Poyang Lake varies, the diversion ratios of the Ganjiang River estuaries is not significantly affected, while diversion ratios of the east and west channels tend to be affected more easily by water level changes in south lake-entering channel.