Numerical study on the morphological evolution of the Qingshuigou channel on the Yellow River Delta in response to changing water and sediment regimes

Abstract

The Qingshuigou channel is the longest channel in the modern Yellow River Delta since its diversion in 1976. To explore the morphological evolution of the Qingshuigou channel on the Yellow River Delta in response to changing water and sediment regimes, we applied the two-dimensional hydro-sediment-morphodynamic coupling model to simulate the characteristics of bed erosion and deposition in Qingshuigou channel and its estuary in different water and sediment regimes. The results demonstrate that regarding the seasonal difference of the year, the sediment deposition in the estuary during the flood season is larger than the non-flood season, and the former accounts for 88% of the annual estuary deposition. On a long-term scale, the erosion of the river channel becomes considerable and the sediment deposits rapidly in the estuary with high water discharge and sediment concentration.