长江口崇明东滩及相邻区域地形演化与驱动因素分析  

Topographic evolution and driving factors of the Chongming Eastern Beach and its adjacent areas in the Changjiang River Estuary

作　　者：郭兴杰[1] 严学新[1] 王寒梅[1] 沙伟 秦渭华 唐迎洲 徐健 Guo Xingjie;Yan Xuexin;Wang Hanmei;Sha Wei;Qin Weihua;Tang Yingzhou;Xu Jian(Shanghai Institute of Geological Survey,Shanghai 200072,China;East China Sea Environmental Investing and Surveying,State Oceanic Administration,Shanghai 200137,China;Shanghai Water Planning and Design Institute,Shanghai 200233,China)

机构地区：[1]上海市地质调查研究院,上海200072 [2]国家海洋局东海海洋环境调查勘察中心,上海200137 [3]上海市水务规划设计研究院,上海200233

出　　处：《海洋学报》2020年第5期95-103,共9页

基　　金：国家自然科学基金(41506103,41706098);上海市科委资助项目(18DZ1206403)。

摘　　要：河口大型滩涂演化关系到航运通畅、生态保护以及近岸工程的安全性,是地貌学和工程界关注的热点。利用单波束测深系统对长江口崇明东滩进行高精度监测,并结合近年来周围环境因素分析其冲淤格局。结果表明:(1) 2011-2017年间崇明东滩和北港北沙基本以淤积为主,北港北汊河槽中央局部形成-2 m心滩,-5 m等深线包络面积基本稳定,整体呈"长高不长大"的格局;(2)海洋来沙是其淤积的主要物源,汊道涨落潮时空分异而形成的两大环流是塑造此地形的主要原因;崇明东滩和北港北沙的淤积直接挤压北港北汊的发展,沙体淤积可能会引起未来两大沙体的并靠;(3)崇明东滩、北支南沿的滩涂整治工程是促进北支萎缩和崇明东滩淤积的重要因素,另外横沙通道落潮分流增加,青草沙围水工程改变了北港河槽的曲率,也有利于北港北沙的淤积。The evolution of large tidal flat in estuaries is related to smooth navigation, ecological protection and safety of offshore engineering. It is also a hot topic in geomorphology and engineering. A single beam bathymetric system was used to monitor the Chongming Eastern Beach in the Changjiang River Estuary. The scouring and silting pattern was analyzed based on the environmental factors in recent years. The results are as follows:(1) Chongming Eastern Beach and the north inlet of the North Channel are mainly deposited in 2011-2017 years, and the northern sand terrain of the North Channel is greater than that of the Chongming Eastern Beach, and the central part of the North Branch of the North Channel is-2 m deep in the central area, which is a silt up situation, and the envelope area of the-5 m contour in the study area is basically stable, and the whole pattern is "long height and no growth".(2) Marine sediment is the main source of silting, and the main circulation of the two large circulation formed by the time and space of the rising and falling of the three branches in the study area is the main reason.(3)The reclamation project in the south of the Chongming Eastern Beach and the North Branch is the main factor causing the North Branch atrophy and the silt of the Chongming Eastern Beach, and the ebb tidal diversion of the cross sand channel. As a result, the curvature of the North Channel is a key factor leading to the deposition of North Sand in the North Channel. The siltation of the two beaches directly squeezed the development of the North Branch of the North Channel, which was the main cause of its transition from the tidal trough to the ebb trough, and the siltation situation in the North Branch of the North Channel may cause the next two large sand bodies.

关 键 词：崇明东滩 汊道 整治 冲淤 

分 类 号：P737.1[天文地球—海洋地质]