Author(s): Zhang Chen; Shan Zheng
Linked Author(s):
Keywords: Yellow River; Yangtze River; Dam construction; Response model; Spatial and temporal erosion and deposition
Abstract: Mega-dams play a significant role in the Yellow River and Yangtze River, but also bring about complex disturbances. In this paper, we identified the similarities and differences in the response of the lower Yellow River to Xiaolangdi dam and the middle reaches of the Yangtze River to Three Gorges Dam. The analysis of data from the last two decades provides a more comprehensive comparison of water and sediment entering and leaving the reservoirs, studying the impact of the two dams in regulating water and sediment. Additionally, the study compared the evolution of the channel morphology below the dams, including the vertical, lateral and longitudinal adjustments of the riverbed, combined with the alluvial phase space model. The downstream widening was drastic at Xiaolangdi dam, while deepening was the dominant change downstream of Three Gorges Dam. Coarsening has been prohibited downstream migration below Three Gorges Dam, but it played a limited role at the Yellow River. Using the delayed response model and the one-dimensional mathematical model, we successfully simulated the spatial and temporal erosion and deposition processes, and compared the erosion centers of the two river reaches. We have proposed a general model for the response of the Yellow River and Yangtze River to dam constructions. And to develop it, we collected response models of large rivers to dams from around the world and proposed path models for different response. This allows for the simulation of spatial and temporal erosion and deposition in response to the dam constructions by different streams and provides a method for trend prediction.
Year: 2024