杭州湾底质的粒度特征和泥沙来源

杭州湾底质的分布,与潮流、波浪作用以及泥沙来源有着密切的关系。作为强潮海湾的杭州湾,潮流作用是主要的动力因素。底质的粒径大小与水动力强度相适应。底质的类型以泥质粉砂和粉砂为主。底质的分布具有一定的规律性,从湾口向湾内,颗粒粒径由细到粗,分选则由差到好。杭州湾的泥沙来源,以海域来沙为主,其中主要是长江输出的泥沙,随涨潮流进入杭州湾。

GRAIN SIZE FEATURES OF BED MATERIAL AND SEDIM ENTARY SOURCE IN THE HANGZHOU BAY

The distribution of bed material of the Hangzhou Bay is related to sedimentary sources underthe action of current and wave.As a macro-tidal estuary of the Hangzhou Bay,the tidal actionis the major dynamic factor,the grain size of bed material corresponds to the hydrodynamicstrenth.The type of bed material consists of mainly muddy silt and silt.The distributionregularity of bed material is as follows:the grain size is from fine to coarse and its sorti-ng is from poor to good landward from the mouth of bay.The sedimentary sources of Hangzhou Bay come mainly from the sea,among of them,thesediments are transported mainlyfrom the Changjiang estuary into the bay by flood tidal current.