崇明东滩沉积环境探讨

为探讨崇明东滩的沉积环境，了解崇明东滩的植被、水动力等对沉积的影响，对崇明进行了为期一年的实地观测和采样实验分析研究，研究结果表明：①沉积物中含有细砂、粉砂、黏土，其中粉砂是主要组分。塑造滩地的动力以潮汐作用为主，波浪作用居于次要地位；②沉积物的平均粒径自北线断面向南线断面、自高潮向低潮滩有逐渐变粗、分选变差的趋势，且平均粒径具有明显的季节变化；③潮滩季节性冲淤变化主要是与不同季节水文条件的差异性、潮滩植被季节变化及风暴天气等有关。

The Sedimentary Environment of the East Tidal Flat of the Chongming Island

To discuss the sedimentary environment of the east tidal flat of the Chongming Island and to know the effect of hydrodynamic behavior and vegetation on sediment,we worked out a result after a year's on-the-spot observation and analysis study by experiment on samples form the east Chongming tidal flat.The result of the study shows:(1)The sediment contains fine and medium sand and clay,and among them,the fine sand is the main composition;the dynamic force of the tidal flat is mainly tide and wave.(2)From the high tidal flat to the low tidal flat and from the north tidal to the south,the grain size gradually becomes coarser and worse-sorted,the mean size shows the variations of seasons.(3)The seasonal change of erosion and deposition has something to do with the difference in the hydrological condition of different seasons,seasonal tidal-flat vegetation and storms.