收藏 ｜ 设为首页 广告服务 ｜ 联系我们 ｜ 在线留言
高级检索

干旱区地理 ›› 2014, Vol. 37 ›› Issue (6): 1155-1162.

• 地表过程研究 • 上一篇    下一篇

库姆塔格柽柳沙包年层粒度特征及其沉积环境探讨

张锦春1，2，3，4，刘长仲1，姚拓1，孙涛3，4，郭春秀3，4，袁宏波3，4，唐进年3，4，丁峰2，4，李学敏3，4，宋德伟4   

  1. （1 甘肃农业大学，草业生态系统教育部重点实验室，甘肃兰州730070；2 甘肃民勤荒漠草地生态系统国家野外科学观测研究站，甘肃民勤733300；3 甘肃省荒漠化与风沙灾害防治国家重点实验室培育基地，甘肃武威733000； 4 甘肃省治沙研究所，甘肃兰州730070）
  • 收稿日期:2014-01-07 修回日期:2014-04-21 出版日期:2014-11-25
  • 作者简介:张锦春（1969-），男，研究员，在读博士，从事荒漠化防治与植被生态领域的研究. Email：zhangjcgs@126.com
  • 基金资助:

    国家自然科学基金（40961013）资助；甘肃省自然科学基金（1208RJZA262）资助

Exploration to sedimentary environment and grain-size characteristics in age layers of Tamarix sand-hillocks in Kumtag Desert

ZHANG Jin-chun1，2，3，4，LIU Chang-zhong1，YAO Tou1，SUN Tao3，4，GUO Chun-xiu3，4，YUAN Hong-bo3，4，TANG Jin-nian3，4， DING Feng2，4，LI Xue-min3，4，SONG De-wei4   

  1. （1 Gansu Agricultural University, Key Laboratory of Grassland Ecosystem, Lanzhou 730070, Gansu, China；2 Minqin National Research Station for Desert Steppe Ecosystem, Minqin 733300, Gansu, China；3 State Key Laboratory of Desertification and Aeolian Sand Disaster Combating, Wuwei 733000, Gansu，China；4 Gansu Desert Control Research Institute, Lanzhou 730070, Gansu, China）
  • Received:2014-01-07 Revised:2014-04-21 Online:2014-11-25

PDF (PC)

50

赞

摘要： 通过3 个典型柽柳沙包年层粒度特征分析，探讨了库姆塔格120 a 以来柽柳沙包沉积环境的演变过程。结果表明：（1）柽柳沙包粒度组分总体以细沙为主，年层平均含量为67.0%，粗沙和粗粉沙分别为13.0%和12.4%，粒径分布细且分选性差，偏态多正偏，个别极正偏，峰态中等偏窄，属典型风成物沉积；（2）柽柳沙包年层粒度空间分布以东部湿地沙包沉积物细，沙粒含量77.2%，平均粒径为2.99Φ，西部谷地沙包沉积物颗粒粗，沙粒含量为85.1%，平均粒径为2.92Φ；而沙包年层粒度时间分布则随着沉积层增加呈现粗粒化，20 世纪以来，柽柳沙包顶部沙粒含量在61.7%～78.8%之间，年层沉积物细，分选性差，底部增为85.5%～96.1%，年层沉积物粗，分选性好。柽柳沙包年层粒度时空变化反映了不同生境条件和不同沉积时段的沉积过程及其风沙环境的多样性变化。（3）120 a 以来柽柳沙包年层粒度反映了库姆塔格沙漠环境以干旱强风气候模式为主，并伴随着明显的干湿交替变化过程。

关键词: 库姆塔格沙漠, 柽柳沙包, 年层, 粒度特征, 沉积环境

Abstract: The Kumtag Desert，China’s sixth largest desert，lies in the south-east of the Lop Nur region，and is famous for the unique dune type of Pseudo-feathery dunes in the whole world. It is expanding and threatening to engulf previously productive lands with its arid wasteland character with the eastward speed of 1-4 m agely. The Tamarix sand-hillocks are one kind of special biological landform types，with legible age layers structure composited by sand and plant litters，in the Kumtag Desert. And their age layers structure was important significance to reveal desert environmental evolution. The paper applied age layers environmental analysis techniques to collect the grain-size sample of three typical Tamarix sand-hillocks in the Kumtag Desert，and the sand-grain characteristics of the age layers were analyzed for discussion the sedimentary environment evolution in the past 120 years. The results suggest as follows：（1）The Tamarix sand-hillocks’granularity composition of grain-size is dominated by the fine sand，whose age layer average content is 67.0 % and the content of coarse sand and coarse powder sand came next，with average value of 13.0% and 12.4%. They are every fine grain-size，badly sorted，a positive or very positive skewness，and a medium and narrow kurtosis，they belongs to aeolian sediments.（2）On the spatial distribution of grain-size，the sediments of the wetlands sand-hillocks in the east is every fine with content of sands accounting for 77.2% and average grain-size value of 2.99 Φ，the valley sand-hillocks in the west is every thick with sands content of 85.1% and average grain-size ranges of 2.92 Φ. On the other hand，the more increased the sedimentation age，the coarser the grain-size of age layers of the Tamarix sand-hillocks in the 20th century，the content of sands is minimum of the top sand-hillocks which changes from 61.7% to 78.8% and its bottom’s one is more whose sand content changes from 84.54% to 97.78%. It reflects the diversity changes of the sedimentation environment in the different habitats and deposition time.（3）The grain-size of age layers of the Tamarix sand-hillocks in the past 120 years reflects that the Kumtag Desert environment is mainly based on the dry-windy climate model and the obviously alternation process of drying and wetting are accompanied with it.

Key words: the Kumtag Desert, the Tamarix sand-hillocks, age layers, grain-size characteristics, sedimentary environment

中图分类号: 

  • P931.3