Analysis on the evolution trend of floodplain in the middle Yangtze River since the operation of the Three Gorges Reservoir
The middle Yangtze River has always been the flood control reach.Although the evolution rate of floodplain in this reach is relatively slow,the long-term cumulative changes of floodplain under new water and sediment conditions are also worth paying attention to.Based on the statistical analysis of the characteristic in-undation flow at multiple typical floodplains in the middle Yangtze River during the 175 m operation period of the Three Gorges Reservoir(TGR),this paper quantifies the changes in floodplain inundation characteristics of the runoff process before and after the impoundation of the TGR.Combined with the analysis of submergence tolerance of floodplain plants to seasonal hydrological fluctuation,it is pointed out that the seasonal inundation caused by the runoff processes before and after the impoundation of the TGR is not sufficient to block the growth and development of floodplain plants.Due to the control effect of a series of water related engineering in the channel,the lateral deformation of floodplains in the middle Yangtze River has been greatly suppressed.With the slow flow and sediment retention effect induced by vegetation on the floodplain,the floodplains in the middle Yangtze River still show a long-term trend of silting up slowly.
river bed evolutionflood plainwet plantssubmergence tolerance
万方数据
维普
