中文摘要：

以实测悬沙粒径、流速、含沙量资料为基础，通过悬沙不同粒级组分、中值粒径以及粒度参数的统计，分析椒江河口最大浑浊带核部悬沙粒径分布变化特性。研究表明，悬沙粒径分选主要受物质来源、潮流动力作用下底部部分物质再悬浮和絮凝沉降3个因素的影响。其中第二个因素起主导作用，大潮期比小潮期显著，第三个因素的作用主要发生在涨落憩前后低流速期，并在表层较近底层的水体明显。

英文摘要：

On the basis of date on particle size, current velocity and sediment concentration, the paper discusses the characteristics of size distribution of suspended sediment by means of the statistics of different size fractions and median diameters and also particle size parameters of suspended sediment. The results show that the size distribution of suspended sediment is mainly influenced by three factors： sediment sources, resuspension of bottom sediment by tidal force, and flocculated settling of suspended sediment. Of which, the second factor is dominative, and the action during the spring tide is more remarkable than that during the neap tide. The action of the third factor becomes active in slack water when the current velocity is low, and more remarkable in the surfer layer than in the lower layer near the bed.