柴达木盆地新月形和穹状沙丘共存形态和成因  

Coexistence of barchan dunes and dome dunes and its causes in the Qaidam Basin

作　　者：马芳 吕萍 曹敏 余军林 夏子书 Ma Fang;Lv Ping;Cao Min;Yu Junlin;Xia Zishu(History,Culture and Tourism School,Fuyang Normal University,Fuyang 236037,Anhui,China;School of Geography and Tourism,Shaanxi Normal University,Xi'an 710062,China)

机构地区：[1]阜阳师范大学历史文化与旅游学院,安徽阜阳236037 [2]陕西师范大学地理科学与旅游学院,陕西西安710062

出　　处：《中国沙漠》2025年第1期185-194,共10页Journal of Desert Research

基　　金：国家自然科学基金项目(42271006);中央高校基本科研业务费专项项目(GK202202004)。

摘　　要：经典沙丘地貌学理论认为沙丘地貌类型与风况一一对应,即不同类型沙丘不应该在同一区域(相同风况)同时存在。然而地球和火星上新月形和穹状沙丘共存地貌的发现与此理论相悖,目前尚不清楚此种共存地貌的发育环境和成因。以柴达木盆地新月形和穹状沙丘共存地貌为研究对象,综合分析沙丘形态、动态变化和发育环境,尝试探究二者共存的成因。结果表明:柴达木盆地共存区沙丘形态均较小,呈现圆形或近圆形穹状沙丘与矮胖型新月形沙丘共存。同一区域新月形和穹状沙丘的移动速率和底面积的关系符合相同的幂函数分布,沙丘形态变化存在由穹状向新月形和新月形向穹状两种演化模式。共存区呈具有明显主风和一定强度次风的双向风况,输沙方向存在78°~95°的季节变化,主风向或输沙方向的季节变化为新月形和穹状沙丘的共存和沙丘形态的改造提供动力。Classical aeolian geomorphology theory holds that each types of dune has individual wind regime and development environments,implying that different types of dunes should not coexist under nearly same wind re-gime.However,the coexistence of barchan and dome dunes has been observed on both Earth and Mars,contra-dicting traditional aeolian geomorphology theories,and the development environment and dynamics of such co-existing landforms are currently unclear.This study focuses on the area in the Qaidam Basin where barchan and dome dunes coexist,comprehensively analyzing the morphological characteristics,dynamic changes,and wind regime to explore the causes of their coexistence.The results indicate that the dune morphology in the coexisting areas of the Qaidam Basin is relatively small.Dome dunes are nearly circular or elliptical,while the barchans are characterized fat or short fat.The relationship between the annual migration rate and bottom area of barchan and dome dunes in the same region follows the same power function distribution,and the morphological changes of the dunes exhibit two patterns:evolution from dome dunes to barchan and transformation from barchan to dome dunes.The wind regime is characterized by a bidirectional wind with a distinct prevailing wind and a certain strength of secondary winds.There is a seasonal variation between 78°-95° in the direction of sand transport,and the seasonal variation in the main wind direction or sand transport direction provides the driving force for the coexistence of crescent and dome shaped sand dunes and the transformation of sand dune morphology.

关 键 词：沙丘共存 风况 沙丘移动 柴达木盆地 

分 类 号：P931.3[天文地球—自然地理学]