长江口北槽悬沙来源的观测与分析

Study on suspended sediment sources in the North Passage of the Yangtze Estuary

为掌握长江口12.5m深水航道北槽段回淤的泥沙来源,2011-2012年采用固定观测站和ADCP与动船取沙结合的方法,对北槽四侧边界进行了3次水文观测,并收集了同期的北槽水文测验数据。基于上述资料,对北槽四侧边界的泥沙输移情况进行了分析。结果表明:北槽四侧边界均存在明显的水沙交换,水沙交换量呈大潮强于小潮,洪季强于枯季的特点;跨越南导堤进入北槽的泥沙最多,是北槽主要的泥沙来源;南导堤越堤输沙主要集中在南导堤的中下段,其来源应为含沙浓度相对较高的南槽和九段沙滩面水域。

A series of hydrologic data in situ observation are collected to study sediment source of suspended sediment in the North Passage. The results show that There exit exchange of tidal current and sediment at foursided region of North Passage,and its intensity in spring tide is much greater in flood season than that in dry season,and much greater in spring tide than that in neap tide. Suspended sediment across south jetty into North Passage is the main sediment source. Sediment transport across south jetty is obvious in the central and lower reach. Tidal current of high suspended sediment concentration across south jetty may come from the South Passage and Jiuduan bar.