摘要
依据1988年7月和12月水文观测资料，通过流、盐、沙的综合分析，认识到长江口拦门沙地区的泥沙运动有与河口其他地区不同的特点。泥沙输移在水平面上和垂直面上存在着多种循环；潮流和盐水截留大量泥沙积聚在拦门沙地区；河口在盐淡水交锋地带，除了涨、落急时段外，发现在转流时期泥砂也可能产生再悬浮，从而形成一个潮周期中出现3次或4次再悬浮的特殊规律。
Results analyzed current, salt, sediment based on hydrographic data ofChangiiang hiver mouth bar in July and Desember, 1988 were as follow. In theChangiiang mver Estuary mouth bar area sediment in the reach where runoffplays an important role moves seaward; sediment in the reach where tidal currentis the main force, moves landward; sediments in the reach where density curentplays an important role drculates vedically; and the sediment on the whole circu-lates in a plane under the impacts of the topography and current.The abundant sediment discharged from the Changjiang fover are trapped atthe mouth bar due to the effeCts of tidal current, runoff and mixing of salt- andfresh-water. There are two different mechanisms controlling the trapping of the sedi-ment by tidal current and salt water. The depositing centre may not be at one placebut in two densely depositing zones in the deep trough.It was found that the sediment of the mixing zone between salt-and fresh-waterwas resuspended three or four times during one tidal period. The reason is relatedto the mixing effect between salt water and fresh water.
出处
《海洋与湖沼》
CAS
CSCD
北大核心
1996年第3期279-286,共8页
Oceanologia Et Limnologia Sinica
基金
国家自然科学基金!9487005
关键词
长江河口
拦门沙
泥沙运动
运动规律
Changjiang River Estuary Mouth bar Sediment motion Sediment resupended
