Author(s): Jing Huan; Yang Mingzhi; Wang Yanjun; Zhou Mengqiang; Zhu Suge; Xu Jijun
Linked Author(s): Yanjun Wang, Jijun Xu
Keywords: Middle Yangtze River; Non-equilibrium response process; Adjustment potential; Adjustment mode
Abstract: Since the operation of Three Gorges Reservoir, the Middle Yangtze River has entered a strong erosion process, leading to the drastic adjustment of the channel geometry, which may threaten the flood control safety and ecological health of the river channel. Therefore, it is crucial to clarify the magnitude and mode of the non-equilibrium evolution adjustments. This paper focus on the Middle Yangtze River, and simulates the spatiotemporal adjustment process following operation of the Three Gorges Reservoir by using the stablished spatiotemporal equilibrium response equation. The results indicate that: (i) In terms of adjustment potential, there are significant differences in each reach. Laterally, the channel width of YC-ZC Reach and Upper Jingjiang Reach remains unchanged, while the broadening potential in the Lower Jingjiang Reach and other lower reaches is slightly larger, showing a widening range of about 20~30m. Vertically, the adjustment potential of accumulated riverbed degradation in most reaches is close to or more than 2.0m, except for the meandering Lower Jingjiang Reach. (ii) In terms of adjustment mode, the YC-ZC Reach and Upper Jingjiang Reach controlled by bedrock nodes are dominated by vertical riverbed incision, while the Lower Jingjiang Reach, CLJ-HK Reach and HK-HK Reach affected by river bank collapse are dominated by slight broadening and vertical degradation. The above results can provide scientific basis for flood control planning and river regulation in the Middle Yangtze River.
Year: 2024