Effect of water depth and waterway obstructions on the divergence and confluence areas of Dongting Lake and the Yangtze River after the operation of the Three Gorges Project  

作　　者：Yunping Yang Hong Yin Ming Li Wanli Liu Kanyu Li Wenjun Yu 

机构地区：[1]Tianjin Research Institute for Water Transport Engineering,Ministry of Transport,Tianjin,China [2]Yangtze River Waterway Regulation Center,Wuhan,China [3]Changjiang Waterway Survey Design and Research Institute(Wuhan),Wuhan,China [4]National Engineering Research Center for Inland Waterway Regulation,Wuhan,China

出　　处：《River》2023年第1期88-108,共21页江河(英文)

基　　金：National Key Research and Development Program of China,Grant/Award Number:2021YFB2600500;Fundamental Research Funds for Central Welfare Research Institutes,Grant/Award Number:TKS20200404;Special Scientific Research Project of Changjiang Waterway Regulation,Grant/Award Number:SXHXGZ‐2022‐1。

摘　　要：Climate change and human activities have profoundly changed the evolutionary processes and developmental trends of the hydrology and geomorphology of rivers and lakes.Such changes have affected the evolution of bars and channels at the intersections of rivers and lakes and the utilization of water depth resources in waterways,which,in turn,have affected the sustainable development of waterways,such as the“Golden Waterway”of the Yangtze River.Considering the confluence of Dongting Lake and the Yangtze River as the present study area,we analyzed the effect of the hydrology of Dongting Lake and the evolution of bars and channels in the Jingjiang reach of the Yangtze River on the depth of the waterways.Our results indicated that from before the operation of the Three Gorges Project(1960–2002)to after its operation(2003–2021),the flow and sediment volume of the three inlets of Dongting Lake demonstrated a continuous decreasing trend.Furthermore,the relative increase in the runoff of the Jingjiang reach increased channel erosion.Channel erosion at the river–lake confluence from 2003 to 2021 created favorable conditions for increasing the dimensions of the waterways.The total length of the river–lake confluence that did not meet the requirements for safe navigation[4.5×200m(water depth×width)]was 12.6 km,accounting for 68.35%of the total length of the Jingjiang reach with obstructed navigation.We observed that a decrease in the low‐water level and“steep slope and rapid flow”were the major factors hindering the navigation of the reach(from Zhicheng to Dabujie)affected by the Songzikou diversion of Dongting Lake.This was mostly reflected by the width of the 4.5m waterway being less than 200 m.A declining water level,shrinking sandbanks and tidal flats,and alternating branches that destabilize the low‐water route were the major factors hindering navigation in the reach(from Taipingkou)affected by the Taipingkou diversion of Dongting Lake.Consequently,alternative waterways were implemented during low�

关 键 词：channel scale river-lake relationship subjunction area Three Gorges Project 

分 类 号：TV1[水利工程]