| 摘要: |
| 根据海岸带和海岛两次调查的实测资料和水下地形图，用动力地貌学方法对长江口三岛岸滩剖面的形态和冲淤变化进行研究。结果表明，分汊河口冲积岛岸滩有“江岸型”、“洲头型”和“潮滩（tidal beach）型”三种基本类型；河槽变迁导致“江岸型”岸滩发生数年周期的变化，岸滩的季节性变化受风、海面、潮差和含沙量等多种因子影响，台风和寒潮则引起周期更短的“风暴旋回”，受植被保护的沼泽滩面的冲淤过程与光滩截然不同。 |
| 关键词: 冲积岛 岸滩剖面 冲淤变化 长江口 |
| DOI： |
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| 基金项目:教育部重点科学技术基金资助项目，（98041号）和国家杰出青年科学基金（49825161号）部分成果 |
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| COASTAL PROFILE SHAPE AND EROSION-ACCRETION CHANGES OF THE SEDIMENT ISLANDS IN THE CHANGJIANG RIVER ESTUARY |
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YANG Shi-lun, YAO Yan-ming, HE Song-lin
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State Key Lab of
Estuarine & Coastal Research, East China Normal University, Shanghai.
200062
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| Abstract: |
| Based on observed and collected data of morphology, sediment, hydrodynamics, and wind, this paper mainly deals with the shape, classification and erosion-accretion cycle of coastal profile of the sediment islands in the Changjiang River estuary. Under silt-dominated and current-dominated conditions, the coastal morphology and morphodynamics in this area are different from those on sandy beaches. Coastal profiles of the islands are classified as three type: “channel bank”, “tidal beach” and “shoal head”. Three basic erosion-accretion cycles are proposed and discussed: (a) “interannual cycle”, controlled by changes in river channel: (b) “seasonal cycle”, influenced by seasonal variations in wind, sea-level and tidal range; and (c) “storm cycle” caused by typhoons or cold waves. Because of the protection of vegetation, morphodynamics in marshes is apparently distinct compared with that on bare flats. |
| Key words: Sediment island, Coastal profile, Erosion-accretion cycle, Changjiang River estuary |
