三峡工程蓄水运用后荆江三口分流河道冲淤变化模拟

三峡工程蓄水运用后下泄水流含沙量大为减小,下游荆江与三口分流河道将长期处于冲刷状态,对江湖关系演变和防洪影响重大。本文利用可视化一维河网水流泥沙数学模型,对三峡工程蓄水运用后荆江三口河道冲淤变化进行了模拟,对三口河道分水分沙量及冲淤变化过程进行了分析。结果表明,在典型水文系列及运用条件下,三峡水库运用后前6年藕池河及松滋河均发生冲刷。之后藕池河有所回淤,松滋河继续冲刷,至三峡水库运用40年左右冲刷达至最大。研究成果对荆江与洞庭湖区防洪决策和水资源研究等有参考意义。

Simulation of erosion and sedimentation at triple-branches of the Jingjiang River after operation of the Three Georges Project

After the operation of the Three Georges Project,the discharged sediment concentration of river flow will be reduced significantly,the Jingjiang River and its triple-branches will be eroded for a long time.This will change the relationship of flow and sediment between the Jingjiang River and the Dongting Lake,thus influence flood situation.By using one dimensional river network sedimentation model,the evolution of erosion and sedin estation of the triple-branches of the Jingjiang River after operation of the Three Georges Project is numerically simulated.The morphological process there is analyzed.It reveals that maximum erosion would appear in about 40 years after project operation.The results would be a good reference to study flood protection and water resources issues of the Jingjiang River and the Dongting Lake.