库布齐沙漠南缘沙丘固定与活化过程中的形态演变  

Morphological Evolution of Dunes during Fixation-Activation Process at Southern Fringe of the Hobq Desert

作　　者：刘丹[1] 管超[1] 周炎广 陶彬彬[1] 哈斯额尔敦[1] 

机构地区：[1]北京师范大学资源学院,北京100875

出　　处：《中国沙漠》2016年第5期1223-1229,共7页Journal of Desert Research

基　　金：十三五国家重点研发计划课题(2016YFC0500805);国家自然科学基金项目(41671002;41171002)

摘　　要：以1998—2014年5期库布齐沙漠南缘的遥感影像为主要数据源,结合野外调查分析了沙丘固定与活化过程中的形态演变,探讨了区域风况和降水等气象要素对沙丘固定与活化及形态演变的影响。结果表明:研究区沙丘随降水量的年际波动经历了固定-活化-再固定3个阶段。监测初期的片状流动沙丘演变为大型抛物线形沙丘并得以固定,固定的抛物线形沙丘以发育风蚀坑形式活化,进而形成多个抛物线形沙丘,最后这些沙丘又被植被固定,沙丘形态趋于更加复杂。但在此过程中,风的作用并不显著。研究区抛物线形沙丘既可起源于新月形沙丘或片状流沙,也可由风蚀坑发育而成,其中植被作为沙丘的重要组成部分,起着重要作用。同时发现在抛物线形沙丘移动过程中,当背风坡发育滑落面时,沙丘的移动最快。Using five remote-sensing images of southern Hobq Desert from 1998 to 2014,and combining with filed measurement,we analyzed morphological evolution of dunes during fixation-activation process,also explored the impact of morphological evolution of dunes during fixation-activation process,such as wind regime and precipitation.Our results showed that with the fluctuation in annual precipitation,the dunes in the southern Hobq Desert experienced at least three statuses,that is fixed,active,and fixed again.At early stage,the platy moving dunes evolved into large parabolic dunes and were fixed by vegetation;and then,there were blowouts showing on those dunes,especially on wings.That a dune was usually divided into several parabolic dunes with different size leaded into a fragmentized landscape and the fixed dunes were active.Several years late,those moving dunes were fixed again.In the end,the dune filed and individual dune became more complex.However,wind speed did not play a noticeable role in the process.It was concluded thatparabolic dunes evolved from not only barchans dune and platy moving dunes,but also blowouts,and vegetation played an indispensable role during the process in the research zone.We also found that dunes advanced at the fastest rate when they developed slip face.

关 键 词：沙丘 固定 活化 形态演变 库布齐沙漠 

分 类 号：P931.3[天文地球—自然地理学]