中文摘要：

以多年数据资料，特别是最新的2003年9月，12月洪枯季和2004年1月枯季南槽设：冒沙水域以及邻近水域各定点观测水沙数据资料为基础，采用水文学、泥沙运动力学和数理统计的方法对没冒沙水域的水沙特性进行了分析．结果表明，该水域落潮流速大于涨潮流速，落潮历时比涨潮历时长；净水量向外海，呈落潮流优势；含沙量普遍较高，大潮平均含沙量1．40kg／m^3，小潮平均含沙量0．60kg／m^3，洪季含沙量比枯季高，洪季大潮涨潮含沙量比落潮高，小潮则相反；枯季不论大小潮，一般都是落潮含沙量大于涨潮含沙量；含沙量垂向梯度的大小潮变化、洪枯季变化和涨落潮变化明显．并且用水流连续方程和拟合挟沙力公式推算了水库工程建设后水流流速和含沙量的变化，估计将对南槽产生一定影响．

英文摘要：

Using the data of years, including the latest in situ data observed in Meimaosha and adjacent water areas in the southern passage of the Yangtze Estuary in Sep. , Dec. 2003 and Jan. 2004, characteristics of hydrology and sediment were studied by the multi-methods of hydrology, sediment transportation and statistics. The results show that tidal currents show a strong ebb dominance as velocity of the ebb current is larger than the flood current, time of the ebb current longer than the flood current. In general, the average suspended sediment concentration is 1.40 kg/m^3 during the period of the spring tide and 11.60 kg/m^3 during the period of the neap tide respectively, The observed data also show that suspended sediment concentration during the flood season is higher than that of during the dry season. Suspended sediment concentration of the flood tide is higher than the ebb tide in the spring tide during the flood season, which is contrary in the neap tide. During the dry season either in the spring tide or in the neap tide, suspended sediment concentration of the ebb tide is higher than the flood tide. The change of the suspended sediment concentration gradient is evident. The variety of the current velocity and suspended sediment concentration after the ecotypic reservoir project have been constructed with the current continuity equation and a linear regression formula of sediment carrying capacity. The result show that it will affect the Nanhui tidal flat in a certain extent.