闽江口近百年来海底地貌演变与成因  

Characteristics of underwater morphology evolution of the Minjiang Estuary in recent 100 years and its reasons

作　　者：陈坚[1] 余兴光[1] 李东义[1] 赖志坤[1] 徐晓晖[1] 黄财宾[1] 

机构地区：[1]国家海洋局第三海洋研究所海岸与海洋地质环境开放实验室,福建厦门361005

出　　处：《海洋工程》2010年第2期82-89,共8页The Ocean Engineering

基　　金：国家基金资助项目(40876043);福建908专项课题资助项目(FJ908-02-02-03);福建省重大专项前期研究资助项目(2005YZ1013)

摘　　要：运用GIS工具研究了闽江口近百年来地貌演变的特征。20世纪上半叶,闽江口表现为较强的淤积,此后淤积速率逐渐降低,1980年代后期到20世纪末河口区以侵蚀为主,河口浅滩主要发育在河口区南部。闽江口南、北支河道具有不同的泥沙输送特征,基本可概括为"北出南积",既北支河道向海输送大部分径流和泥沙,泥沙沉积在河口及三角洲前缘地区,河口区泥沙可再悬浮,通过涨潮流向南支输送,与南支水道带出的泥沙一道促使了南支口外浅滩的发育。1975年以后入海泥沙呈减少的趋势,其主要与水库建设和下游河道采沙等活动密切相关,泥沙供应的变化进一步引起了河口海底的侵蚀。Morphological evolution of the Minjiang Estuary in recent 100 years has been studied with tools of GIS.Results show that high deposition happened in the first half of last century,after that deposition rate declined and erosion happened during late 1980 to end of the century.Shoals mainly develop in the south part of the estuary.The north channel outputs more fresh water and suspended sand than the south channel.Re-suspension often takes place in the estuary,and along with flooding currents,the re-suspended sands may be transported to the south channel.In the end,a combination of relatively weak runoff of the river,relatively high flooding current in the south channel,and re-suspended sands from the estuary,makes the high deposition rate and form more shoals in and out of the south channel.The decline of deposition rate and erosion in the estuary is greatly due to the dam construction and dredging on river bed.

关 键 词：地貌演变 泥沙过程 闽江口 

分 类 号：TV148[水利工程—水力学及河流动力学]