Deposition of sandstorms in a vegetation-covered sand dune in Ejin Oasis and its characteristics
Deposition of sandstorms in a vegetation-covered sand dune in Ejin Oasis and its characteristics作者机构:Sehool of Geography South China Normal University Guangzhou 510631 China State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment CAS Xi'an 710075 China Department of Tourism Resourees and Environment Foshan University Foshan 528000 China
出 版 物:《Journal of Geographical Sciences》 (地理学报(英文版))
年 卷 期:2006年第16卷第4期
页 面:502-508页
核心收录:
学科分类:07[理学] 070601[理学-气象学] 0706[理学-大气科学]
基 金:National Basic Research Program of China, No.2004CB720206 Knowledge Innovation Project of CAS, No.KZCX2-SW-118
主 题:Ejin Oasis vegetation-covered sand dune dust storm sandstorm grain size major chemical element
摘 要:"Ejin Section" found in a typical vegetation-covered sand dune in Ejin Oasis was investigated. In this study, 263 samples were taken from the section for grain-size analysis, 25 for chemical analysis, 11 for ^14C dating and 6 for scanning electron microscope (SEM). The results of the study indicate that 3 types of the sediments in the section can be identified, YS, LS and ST. YS, homogeneous yellow-brown dune sands, is equal to those of inland deserts, LS, loess-like sandy soils, is the same as the sandy loess in the middle Yellow River and modem falling dusts, and ST, sandy sediments interbeded with the deadwood and defoliation of Tamarix spp, represents the depositional process of the section interrupted by abrupt changes in climate. The Ejin Section has recorded the repeated dust-storms or sandstorms since 2500 yr BP and the peak periods of the dust-storms or sandstorms revealed by the section are consistent with the records of "dust rains" in historical literatures, indicating that the change of climate is a key factor to increase sandstorms or dust-storms, whereas, "artificial" factor may only be an accelerating one for desertification.