羽毛状沙丘辨析  

The Identification of Feathery Dunes

作　　者：董治宝[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所沙漠与沙漠化重点实验室,兰州730000

出　　处：《科技导报》2009年第20期69-75,共7页Science & Technology Review

基　　金：国家自然科学基金重点项目(40638038)

摘　　要：近年来,随着库姆塔格沙漠研究的深入,中国学者对羽毛状沙丘的争论愈来愈多。本文综合分析了国内外沙丘分类学中关于羽毛状沙丘的论述,确认羽毛状沙丘是复合线形沙垄的变型,其中沙垄主脊构成"羽柄",而叠加其上的次级沙丘脊歧出主沙丘脊,构成"羽毛"。对比分析世界其他沙漠与中国库姆塔格沙漠所谓羽毛状沙丘的形态学特征发现,库姆塔格沙漠所谓的羽毛状沙丘实际上是典型的赛夫沙丘,不应视为羽毛状沙丘。以往根据遥感影像确定的羽毛状沙丘的"羽毛"部分是由地表沉积物反照率对比形成的羽毛状图案,与垄间地的沙埂没有很好的对应关系。羽毛状沙丘是在比较复杂的风况和沙源供应不够充分的条件下形成的。因此本文认为以往关于库姆塔格沙漠羽毛状沙丘的不确切认识概念应予以纠正。Chinese scholars are paying unprecedented attentions on feathery dunes in recent years in their studies on the Kumtagh Desert, but with widely divergent views on feathery dunes. This paper reviews dune classifications proposed by several authors. It is shown that a feathery dune is a variation of a compound linear ridge, in which the main ridge acts as a ＂shaft＂ and subsidiary dunes diverging from the main ridge act as ＂feathers＂. Comparing the morphology of the feather dunes reported in other deserts around the world and that in the Kumtagh Desert of China, one may see that the so-called feather dunes in the Kumtagh Desert are in fact not real feather dunes, but typical seif dunes. The ＂feathers＂ erroneously assumed on remote sensing images are patterns reflecting albedo contrast of the ground surface sediments. They are not related to the relief on the inter-seif dune corridors. Feather dunes are developed in the complex wind regime under the condition of insufficient sand supply. That misconception of feather dunes held by some Chinese scholars should he corrected.

关 键 词：风沙地貌 沙丘分类 羽毛状沙丘 

分 类 号：P931.3[天文地球—自然地理学]