The Influence of the Sediment and Water Transported by the Yellow River on the Subaqueous Delta Without Water and Sediment Regulation

The subaqueous delta of the Yellow River has been affected by its high sediment concentration, and the water and sediment control measures have changed in recent years. In this paper, Delft 3D software was used to simulate the sediment diffusion in the subaqueous delta of the Yellow River in 2017 so as to explore the influence of the sediment and water transported by the Yellow River on the subaqueous delta without water and sediment regulation. The results reveal the occurrence of a low-high-low suspended sediment concentration distribution from the coastlines to the far shore. The main accumulation areas shifted from the coasts of Bohai Bay and Laizhou Bay in the dry season to the estuary in the wet season. The sediment formed a deposition zone along the coastline, which widened from the estuary outwards, and there was an outer erosion zone under the actions of wind and waves. In 2017, the impact of the sediment inflow into the Yellow River on its subaqueous delta generally resulted in the erosion being greater than the sedimentation, and the erosion/deposition volume in 2017 was -1.28×108 m3, and the estimated critical value of the sediment inflow balance was 2.13×108 tons.