对比分析我国西北与海岸地区新月型沙丘形态及成因差异

Comparative Analysis of Morphology and Formation Mechanism of Barchan Dunes of Northwest Inlands and Coastal Areas

本文选择西北的库母塔格、乌兰布和沙漠与中国河北昌黎黄金海岸和北戴河翡翠岛沿岸的新月型沙丘为研究对象,选择沙丘的数量和规模、沙的粒度为指标作形态和形成机理的对比分析。结果显示海岸地区新月型沙丘的规模小于西北,沙丘排布和形态相对规则,海岸沙丘粒度较小;西北地区新月形沙丘粒度各地差异大,沙丘的不同部位粒度分异明显。两地新月形沙丘形态与粒度差异明显的原因是:内陆风力强劲,风向多变;海岸地区沙丘是在水与定向力共同作用下形成的。

This article compared and analyzed morphology and formation mechanism of barchan dunes of northwest inlands and coastal areas.The differences were revealed by comparison between Kumtag and Ulan Buh deserts of inlands and Changli gold coast and jadeite islands of coastal areas.The results showed that the dunes of inlands were smaller on scales,distribution areas than these of coastal areas.The space distribution and shape of dunes were relatively regular and the grain-size was very small in coastal areas.The differences of grain-sizes were larger in different zones and the particles of a dune varied with different dune fractions in inlands.The wind force was very strong and its direction was variable.Therefore,different size and complex shape were formed on dune of inlands.Because dune formation was the interaction of water and regular wind,size and grain were small and shape was regular on dune ofcoastal areas.