长江河口岸滩侵蚀与防护

COASTAL EROSION OF THE YANGTZE ESTUARY

长江三角洲是一个冲积性三角洲,长期以来由于河流带来的巨量泥沙,使得河口地区一直处在堆积的过程中。但是,20世纪中叶以来,随着全国海岸带的侵蚀情况加剧,尤其是三峡工程等重大工程的影响,人类活动对河流输沙产生了非常重要的作用,使得长江河口地区海岸蚀积形势发生了变化。搜集了19世纪中叶到20世纪80年代的海图资料,通过GIS工具生成河口段地区数字高程模型(DEM),对比了从徐六泾到口外海滨段地貌的时空变化。分析认为,长江河口段地区的地貌蚀积形势发生了逆转,蚀积格局为"一线稳定,两线侵蚀,四面堆积",河流输沙减少是产生这种格局的根本原因,并对采取的防护对策作了探讨。

The Yangtze delta is an alluvial delta which has sediment discharge from the Yangtze River deposit in. For a long time,it has been in the process of deposition due to the great deal of sediment from the Yangtze River. However,since the mid of last century,the situation of deposition-erosion of the Yangtze estuary has been changed with the strengthening coastal erosion in China. The decrease in sediment discharge plays an important role under the influence of human activities,such as the Three-Gorge project....