1997—2023年长江口河床演变及潮汐反馈模拟

Evolution of the Yangtze River Estuary from 1997 to 2023 and tidal strength feedback simulation

  • 摘要: 为探讨强人类活动下长江口河床演变特征及对潮汐的影响、支撑长江口的保护与治理,根据1997—2023年长江口地形资料,结合潮流数学模型情景模拟,研究了长江口陆侧岸线、河床冲淤的变化,以及由此带来的长江口潮汐强度的变化。结果表明:1997—2023年,长江口陆侧岸线外拓造成河道宽度平均减少2400 m、水域面积减少643.79 km2、容积增加1.36亿m3、平均水深增加1.34 m,呈现“河道缩窄、滩淤槽冲、串沟发育、河槽加深”的特征;受1997—2023年长江口陆侧岸线变化及河床冲淤影响,长江口南支、南槽、北支上段潮汐动力增强,北港、北槽、横沙通道潮汐动力减弱,潮汐动力发生异变。本研究成果可为长江口的保护与治理(如河势控制、海塘达标建设等)提供参考和借鉴。

     

    Abstract: In order to explore the evolution of the Yangtze River Estuary (YRE) and the feedback of tidal strength under strong human intervention, the changes in the shoreline, erosion and deposition patterns, and tidal strength were studied based on YRE bathymetry data from 1997 to 2023, and a scenario simulation of the YRE using a tidal mathematical model was conducted. The results showed that, under the influence of strong human activities from 1997 to 2023, the shoreline of YRE expanded toward the sea, resulting in an average reduction of 2400 m in river width, a decrease of 643.79 km2 in water area, an increase of 136 million cubic meters in volume, and an increase of 1.34 m in average water depth. The results also revealed a trend of “river channel narrowing, shoal silting, channels eroding, groove developing, and riverbed deepening.” The tidal strength in the South Branch, South Passage, and the upper part of the North Branch of YRE increased, while the tidal strength in the North Channel, North Passage, and Hengsha Channel decreased. Finally, there was no significant change in the other regions of the YRE. The results of this study can provide useful guidance for the protection and management of YRE, such as river regulation and dike construction.

     

/

返回文章
返回