长乐东部沿海海岸风沙区域分异探讨  

A DISCUSSION ON THE REGIONAL DIVERGENCE OF EOLIAN SAND ALONG THE COASTAL AREA OF CHANGLE

作　　者：陈方[1] 蔡明理[1] 李祖光[1] 汪榕光 张文开[1] 

机构地区：[1]南京大学海岸与海岛开发国家试点实验室,福建师范大学地理系,南京大学海岸与海岛开发国家试点实验室基金

出　　处：《南京大学学报（自然科学版）》1995年第3期487-494,共8页Journal of Nanjing University（Natural Science）

基　　金：福建省自然科学基金

摘　　要：根据长乐东部沿海不同岸段风沙的化学成份、矿物成份、沙色、粒度特征和风沙地貌特征等研究结果，阐明了由于沙源、向岸风与岸线夹角、原始地形和海滩坡度等因素在时空组合上的不同，使得海岸风沙的堆积特征、发育模式、地貌类型及其组合在不同岸段显示出明显的区域分异性。邻近河口的北段沙源充足，风沙地貌类型多，沙丘带规模大，堆积特征接近于河口沙。中段沙源枯竭，有效风能大，地貌类型单一，堆积物具有二次搬运和分选的特征。南段则介于上述两者之间。Along the coast of Changle, coastal eolian sand makes a wide subtropical coastal dune belt. Its distributing direction is NE --NNE and runs parallel to coastline. Coastal eolian sand develops under the backgrounds of subtropical maritime monsoon climate and normal sea level since late Hoolcene. Sufficient sand supply, wide beach, strong onshore wind and available topographic spaces are the basic requirements for the formation of coastal eolian sand;the trend of the drying and cooling of climate and the strengthening of human activities are the trigger factors to speed up the formation of coastal sand dunes.This paper discusses the regional divergence of coastal eolian sand. It expounds that sand supply, the angle of the onshore wind incidence on the coastline, primeval topography and beach solpe are the major factors affecting the regional divergence. Owing to the differences of the time and spacial combination of the factors, the chemical and mineral compositions, sand colures, grain sizes, topographic types and their ccombinations, developing models of eolian sand are quite distinct in different regions. They are all the peculiar results of the eolian sand in various developing phases and environments.The eolian sand characteritics of north coast are the closest to those of the estuarine sand.The sand supply is sufficient, the coastal dune belt is broad in scale and the topographic type of eolian sand is complicated north coast. Its developing model of coastal dune is as follows (from the coast to inland): incipient dune→foredune→transverse dune→round and elliptic dune,parabolic dune, upsiloidal dune→and sheet. The effective effort of onshore wind is strongest in middle coast as the low beach slope and critical shear velocity. Tall and typical transverse dune is found in the area. Because the sand supply is exhausted now. eolian sand of middle coast is subjecting itself to the wind erosinn and transformation. The eolian sand is stamped with the brand of being transported and sorted once again. Beach sl

关 键 词：海岸风沙 海岸沙丘 海岸地貌 堆积 发育 

分 类 号：P737.172[天文地球—海洋地质]