| 摘要: |
| 文章基于长江口南槽1998年以来长序列水下地形、水沙观测数据和大型涉水工程实施情况，分析南槽近期河床冲淤变化过程，总结演变特征并探讨成因。结果表明：近25年，南槽河床演变总体呈现“缓慢冲刷-趋于平衡-加速冲刷”的三阶段变化特征。在流域减沙与大型涉水工程共同作用下，南槽河槽冲淤分布从“上冲下淤”向“整体冲刷、局部淤积”转换，主要沙体淤积放缓、局部低滩冲刷。未来，在稳定河床边界和较低含沙量条件下，南槽短期内仍将延续冲刷态势，直至趋于新的平衡。 |
| 关键词: 南槽 河床演变 水沙变化 涉水工程 |
| DOI： |
| 分类号:TV147????????????????? |
| 基金项目:国家自然科学基金资助项目（U2040204） |
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| Characteristics of riverbed evolution and its influencing factors in the South Passage of the Yangtze River estuary (1998-2023) |
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Liu ru lan1, Cheng hai feng2
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1.Shanghai Maritime University;2.Key Laboratory of Estuarine and Coastal Engineering
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| Abstract: |
| Based on the observation data of underwater topography, water-sand, and the implementation of large-scale water-related projects since 1998, the paper analyses the recent riverbed scouring and siltation process in the South Passage of the Yangtze River estuary, summarizes the evolution characteristics, and discusses the causes of the change. The results show that in the past 25 years, the riverbed evolution in the South Passage is generally characterised by a three-stage change, namely "slow scouring - tendency to equilibrium - accelerated scouring". Under the combined effect of basin sand reduction and major water-related projects, the distribution of scour and siltation in the South Passage has changed from "upward scour and downward siltation" to "general scour and local siltation", with slow scour of the main sand body and local scour of the lower bank. In the future, under conditions of a stable bed boundary and low sand content, the South Passage will continue to be flushed in the short term until a new equilibrium is reached. |
| Key words: South Passage riverbed evolution water and sediment variation water-related projects |
