摘要
闽江口海岸沙丘的物质来源于以闽江泥沙为沙源的海滩沙，宽广的海滩、强劲的向岸风与干旱的时空耦合，适宜的地形空间构成了海岸沙丘发育的基本条件。海岸沙丘起源于约２５００ａＢ．Ｐ．，其活动是多幕次的，唐、宋及近代几次气候干冷期的出现，人口陡增以及垦荒规模扩大等人为因素，促进了海岸沙丘的发育进程。海岸沙丘从海向陆按雏形沙丘，岸前沙丘，横向沙丘及沙丘链，圆形、抛物线型或Ｕ型沙丘及风积平原依次演化。
Along the south coast ofMinjiang estuary,coastal eolian sand makes a wide subtropical coastal dune belt.Its distributing direction is NE-NNE and runs parallel to coastline:Coastal sand dunes develop under the subtropical maritime monsoon climate and normal sea level since late Holocene.Sufficient sand supply,wide beach,strong onshore wind and the space time linkage of dry and stong windy season,available topographic space,the occurrence of periodic cold and dry climate under the trend of drying and cooling,and the strengthening ofhuman activities are the decisive factors to the development of eolian sand dunes. The topographic types of sand dunes are incipient dune,foredune,transverse sand ridge and range,round and elliptic dune,parabolic or upsiloidal dune and sand sheet in their proper order from coastal to inland.Coastal eolian sand is a complicated system composed of natural and human factors.The kernel of its process-response system is thatthrough the transport of sand grains eolian sand dunes exert a self organized process of surface topography and attain a harmonious development between topographic structure and dynamic environment. The age of 14C dating illustrates that the coastal sand dunes began to develop 2470±90aB.P.On their early stage,it presented a slow natural desertization process.From 250 a B.P.to now they are in a period of great prosperity and show a natural human desertification process.
出处
《中国沙漠》
CSCD
北大核心
1996年第3期227-233,共7页
Journal of Desert Research
基金
福建省自然科学基金
南京大学海岸与海岛开发国家试点实验室基金
