摘要:
沉积物粒度参数是表征其分布和输运特征的重要信息。根据2005年7月和2006年12月采集的167个表层沉积物样品以及收集到的实测水文资料，以杭州湾北岸为例，分析研究强潮海湾近岸表层沉积物的时空变异特征，同时在应用GSTA模型对沉积物进行输运趋势分析的基础上探讨该区域的泥沙来源，并通过掀沙计算分析表层沉积物对高能水动力环境的响应过程。结果表明：（1）杭州湾北岸表层沉积物普遍较细，以粉砂质粘土为主，在南汇、金山岸段存在两个砂质密集区，并且随动力条件的不同在由岸向海方向呈现出逐渐变细的粒度趋势；（2）表层沉积物粒度特征在洪、枯季亦存有差异，枯季较洪季存在普遍粗化现象；（3）GSTA模型结果显示该区域泥沙主要来源于上游岸段来沙和湾口海域来沙，此外局部区域之间的泥沙交换过程也是区域内泥沙平衡协调的重要途径；（4）潮流掀沙作用主要以南汇和奉贤水域为主，波浪掀沙作用范围基本覆盖研究区域的整个岸段，且波高为1.5 m（P=94.9%）以下的波浪掀沙作用对浅水区域的影响最为显著。
Abstract:
Grain size parameter is the most important information of sediment, which can point out the characteristics of distribution and transportation. Based on analysis data of 167 samples which were collected from the north coast of Hangzhou Bay in June 2005 and December 2006, a study on the rules of temporal and spatial changes in properties of seabed surface sediment in strongtide bay is conducted. As well as, through the Grain Size Transport Analysis model, a conveying trend analysis of sediment in this basin has been studied, in the base of which a research of sand sources is primarily discussed. Finally, the response process of tidal flat sediment to the highenergy hydrodynamic environment is also analyzed. The results indicate that: (1) The grain size of tidal flat sediment in north coast of Hangzhou Bay is generally small, and silty clay is the main sediment types in this basin; (2) The vertical difference of grain size characteristics is more obvious than the transversal, and also there is some seasonal variation between flood season and withered season; (3)The results of GSTAmodel show that，the sediment of this basin is mainly from the upstream and the sea waters. As well as , the interregional sediment exchange is another important method to get the balance of sediment supply in this basin；(4) Agency coverage where tide current can stir surface sediment is mostly the Nanhui and Fengxian water area, while the wave stirring agency coverage almost covers the whole section of the research basin, on which the wave height below 1.5m effect most significantly.
