【摘要】 崇明岛西沙湿地、南分场、团结沙和东滩湿地的沉积物粒度分布,具有高潮滩向低潮滩平均粒径逐渐变小、标准偏差变大(分选性变好)的共同变化特征,基本上反映了潮滩水动力条件的变化规律。崇明西沙湿地、南分场和团结沙潮滩坡度大、滩面窄,沉积物粒径比崇明东滩湿地小,中潮滩侵蚀严重,具有"江岸型"剖面的特点;东滩湿地沉积物粒径大,滩面宽、坡度小,具有"潮滩型"剖面的特点。西沙湿地动植物组成单一,生物多样性程度降低,主要是受自然与人类活动的双重影响,该处面临的问题是如何进行生态恢复。东滩湿地需要考虑合理的围垦,过度围垦不但直接破坏了底栖动物的生存,而且威胁到迁徙鸟类的食物来源和栖息地。更多还原

【Abstract】 Chongming Island is the third largest island in China,which is formed by land and sea interaction during the Holocene period. Geomorphology study of river mouth is very important to coastal and ocean engineering and wetland protection and amelioration. Seven cross-wetland sections have been surveyed and surficial sediments were collected from high tidal flat,middle tidal flat and low tidal flat respectively. Grain size of wetland sediments from Xisha,Dongtan,Nanfenchang and Tuanjiesha sections were analyzed. The results show the average grain size of wetland sediments diminishes from high tidal flat to low tidal flat gradually,while standard deviation increases. The mean grain size of "channel bank" type as represented by Xisha,Nanfengchang and Tuanjiesha sections is larger than "tidal beach" type as represented by Dongtan section. This phenomena explains tidal current has a great impact on grain size. Besides,the ecosystem and biodiversity of Xisha and Dongtan wetland were analyzed. The negative influence of human activity on ecosystem is destroying the Biodiversity of Xisha wetland. Excessive reclamation on Dongtan wetland not only affects the survival of the benthic fauna,but also damages the habitats and food source of migrant birds.更多还原