摘要
本文通过对西藏错那湖地区基岩、第四纪沉积和风沙堆积的填图和采样,测量其化学元素成分,应用复合指纹识别技术定量化查明风沙沉积的物源组合及其贡献百分比,从而为错那湖地区更科学地进行沙漠化防治提供数据支撑和实践指导。分析结果表明:①使用复合指纹识别技术定量查明了错那湖东侧巴索曲、龙庆南沟和桑曲3个风沙分布区的物质来源,风沙主要来源于湖的东岸和北岸;②错那湖地区风沙的物质来源差异很大,以东岸贡献为主,对3个风沙区的贡献率分别为82.3%、60.4%和10.1%,呈现出自南向北逐渐减小的趋势;③结合青藏铁路分布可知,东岸物源对铁路的威胁最大,北岸物源仅对铁路以东到山坡的狭长区域有一些影响。夏季高温多雨期,巴索曲、龙庆南沟和桑曲3条河流将中上游的冻融、风化形成的细颗粒物质通过流水作用源源不断地输送到湖滨区域,来年冬春季干燥大风期时,这些暴露的细颗粒物质被大风输送到东侧形成风沙区,基于这一作用机理的认识,认为本地区风沙对铁路的威胁是持续的、长期存在的。因此,在铁路西侧防沙措施的基础上,还应加强铁路东侧的风沙的治理,并在铁路和山坡之间的狭长地带也设置一些防沙设施。
In this study,based on the mapping and sampling of bedrocks,quaternary sediments,and aeolian sand deposits in the Cuona Lake area as well as the analysis of their chemical composition,we used composite fingerprint identification technique to quantitatively investigate the source composition and contribution rate of each source to sand deposits,which can provide data support and practical guidance for the desertification control in the Cuona Lake area.The analysis results show that:(1)Using the composite fingerprinting identification technique,we have quantitatively identified the material sources in three aeolian sand distribution areas of Basoqu,Longqing South Gully and Sangqu on the east side of Cuona Lake,which indicates that the aeolian sand mainly drives from the east and north shore of the lake.(2)The material sources of aeolian sand vary greatly in the Cuona Lake area,most of which are mainly composed of the east bank source.In the aeolian sand distribution areas of Basuoqu,Longqing South Gully and Sangqu,the average contribution rates of east bank source is 82.3%,60.4%and 10.1%,respectively,showing a decreasing trend from north to south.(3)Considering the route of the Qinghai-Tibet Railway,we conclude that the east bank source poses the greatest threat to the railway,while the north bank source has certain influence only in the narrow zone between the railway and the hillside.During the high temperature and rainy period in summer,the three rivers of Basoqu,Longqing South Gully and Sangqu continuously transport the fine particles,which were formed by freeze-thaw action and weathering in the middle-upper reaches of these rivers,to the lakeside area through flowing water.During the dry and windy period in winter and spring next year,these exposed fine particles are transported to the east side by strong wind to form the aeolian sand area.Based on the understanding of this mechanism,we believe that the threat of aeolian sand to the railway in this area is persistent and permanent.Therefore,on the basis of sand control measures on the west side of the railway,the control of aeolian sand on the east side of the railway should be strengthened,and some sand control facilities should also be set up in the narrow zone between the railway and the hillside.
作者
段金龙
谭利华
杜世松
陈长委
伍永秋
DUAN Jinlong;TAN Lihua;DU Shisong;CHEN Changwei;WU Yongqiu(School of Government,Beijing Normal University,Beijing 100875,China;Faculty of Geographical Science,Beijing Normal University,Beijing 100875,China)
出处
《资源科学》
CSSCI
CSCD
北大核心
2019年第12期2316-2326,共11页
Resources Science
基金
第二次青藏高原综合科学考察研究专题（SQ2019QZKK1606）
国家重点基础研究发展计划项目课题（2013CB956001）
关键词
风沙物源
复合指纹识别技术
多元混合模型
贡献率
青藏铁路
错那湖
source of aeolian sand
composite fingerprinting identification technique
multivariate mixed model
contribution rate
Qinghai-Tibet Railway
Cuona Lake
