近50年来杭州湾七姊八妹列岛海域海床演变分析  

Analysis of seabed evolution of Qizibamei Islands sea in Hangzhou Bay in recent 50 years

作　　者：王卫远[1] 贾建伟 杨娟[1] 何倩倩[1] 

机构地区：[1]中国电建集团华东勘测设计研究院有限公司,浙江杭州310014 [2]长江水利委员会水文局,湖北武汉430010

出　　处：《应用海洋学学报》2014年第4期581-584,共4页Journal of Applied Oceanography

基　　金：华东勘测设计研究院科技资助项目(KY120206-04-01)

摘　　要：七姊八妹列岛海域位于杭州湾南部的灰鳖洋内,除了岛礁周围局部存有深沟外,其余地区海床平缓.为了探究该海域海床演变情况,在了解杭州湾来水来沙特征基础上,分析了七姊八妹列岛海域的水动力、悬沙和底质分布特征.不同时期海图的对比分析表明,该海域近岸水深较小,人类活动频繁,围涂筑堤工程较多,一直处于淤积状态,属淤涨型岸滩,而离岸较远的海域,泥沙难于落淤而随潮反复搬运,基本处于冲淤平衡状态.1962～2008年这46 a间,七姊八妹列岛海域总体呈现与岸线走向一致的淤积、冲刷间隔分布的冲淤带.平均淤积厚度约2.2 m,淤积幅度约5.0 cm/a,大多数地方平均冲刷厚度约2.4 m,冲刷幅度约5.0 cm/a.这些特点与当地的水动力条件和泥沙沉积特性相一致.Qizibamei Islands sea is located in Huibieyang sea of southern Hangzhou Bay.Most of the seabed is gentle,in addition to some deep holes around islands and reefs.In order to explore the seabed evolution of the sea area,based on the knowledge of water and sediment characteristics of Hangzhou Bay,the characteristics of hydrodynamic,suspended sediment and seabed material distribution are analyzed.Comparison study on charts from different periods shows that the offshore water is shallower because of human activities and engineering constructions,where it is in a state of deposition and of silting beach.The area far away from the shore is in a balancing state of scouring and silting because sediment is difficult to silting by the tidal movements.Between 1962 ～ 2008,Qizibamei Islands sea presents scouring and silting zone interval to coincide with the shoreline.The mean deposition thickness is about 2.2 m and deposition rate is about 5.0 cm/a.In most areas,the mean erosion thickness is about 2.4m and erosion rate is about 5.0 cm/a.These features are consistent with the local hydrodynamic conditions and sediment characteristics.

关 键 词：海岸泥沙 杭州湾 七姊八妹列岛海域 海床演变 

分 类 号：TV148[水利工程—水力学及河流动力学]