舟山岛域围垦对邻近水道泥沙运动和海床演变影响分析  

Influence analysis of sediment dynamics and seabed evolution in adjacent channel under Zhoushan islands reclamation project

作　　者：季有俊[1] 刘杜娟[1] 黄潘阳[1] 黄承力 

机构地区：[1]国家海洋局第二海洋研究所工程海洋学重点实验室,杭州310012

出　　处：《水道港口》2015年第2期112-120,共9页Journal of Waterway and Harbor

基　　金：国家海洋公益性行业科研专项经费项目资助(201305009);国家海洋局第二海洋研究所科研业务费专项项目资助(SJ1307)

摘　　要：舟山海域岛域围垦与一般近岸滩涂围垦不尽相同,具有地理位置和水动力环境的特殊性。采用舟山钓梁围垦区附近海域不同时期的水下地形资料,并结合邻近螺门渔港水道围垦前后2个时期的水文泥沙调查资料,对岛域围垦环境下水道附近海域泥沙动力和海床冲淤变化特征进行了分析。结果表明,岛域围垦后螺门渔港水道潮汐变化并不显著,但是潮流流速大幅度减少,潮流挟沙能力随之减弱,净输沙量减少了90.1%,且净输沙方向由落潮方向变成涨潮方向。泥沙动力条件的改变促使水道及附近海域海床冲淤环境发生根本性变化,由围垦前槽冲滩淤演变为围垦后大幅度淤积,水道最大淤积厚度可达26 m。根据分析认为,围垦工程改变了水道悬沙的输移沉降模式,围垦前大量的泥沙以过境形式输移,而围垦后悬沙进出因围垦而形成的岙湾将以沉降为主。The islands reclamation in Zhoushan sea area has particularity of geographic position and hydrody-namic environment, which is different from general nearshore tidal flat reclamation. Based on different periods of un-derwater topography data in the surrounding waters of Diaoliang reclamation district, and combined with hydrologi-cal survey data of Luomen Fishing Port Channel before and after reclamation, the variation characteristics of sedi-ment dynamics and seabed evolution under islands reclamation environment were studied. The results show that thetide variation of Luomen Fishing Port Channel is not significant, but the tidal current velocity decreases sharply.Meanwhile sediment carrying capacity of tidal current also weakens, causing a significant reduction of suspendedsediment flux in the channel. The net sediment flux is decreased by 90.1%. However, the sediment transport direc-tion changes from ebb tide direction to flood tide direction. The changed condition of sediment dynamic causes thevariation of erosion and deposition in the adjacent channel, which is mainly presented from channel erosion andfloodplain deposition before reclamation to a large range of deposition after reclamation. The maximum depositionalthickness in the channel can reach 26 meters. According to the analysis, under reclamation project,the sedimenttransport and deposition model was changed significantly. Before reclamation, a large amount of sediment transportin the channel in the form of transit, but after reclamation, suspended sediment entering or leaving the bay formedby the reclamation were mainly deposited.

关 键 词：岛域围垦 泥沙动力 海床演变 峡道效应 舟山海域 

分 类 号：TV142[水利工程—水力学及河流动力学] O242.1[理学—计算数学]