Evolution Trend of the Changjiang (Yangtze) Estuary with reduced incoming sediment

Abstract

The reduction of fluvial sediment input has brought new features to the evolution of the Changjiang (Yangtze) Estuary. The response of river channels and shoals in the Changjiang Estuary are still unclear. A two-dimensional model of water and sediment transport in the Changjiang Estuary is established by using MIKE21. The sediment gradation and the flocculation of the fine sediment have been considered in the model. After calibration, the future evolution trend of the Changjiang Estuary was simulated based on the measured terrain in November 2016. The inflow of water and sediment at Jiangyin from 2008 to 2017 were taken as the upstream inlet conditions. The simulation results show that the pattern of river channel and shoals in the Changjiang Estuary will basically remain, and the main trend of bed evolution is erosion in deep channel and siltation of shoals.