摘要
对呼伦贝尔沙地现代风蚀坑表层沙质沉积物与坑后沙丘垂直剖面沉积物进行了粒度分析,讨论了坑后沙丘剖面的形成过程及风成沙粒度变化的原因。结果表明:呼伦贝尔沙地风蚀坑表面及坑后沙丘剖面沉积物粒径以细沙和中沙为主;风蚀坑表面沉积物粒径及分选参数在风蚀坑各部位呈现波动式变化;平坦草地上的现代土壤与坑后沙丘下伏古土壤为同一层。基于粒度和沙丘移动过程综合分析,认为坑后沙丘剖面中风成沙粒度的垂向变化与沙丘在堆积和移动过程中剖面在坑后沙丘相对位置的变化具有紧密联系,密集采样得出的剖面中风成沙粒度的垂向变化是否能直接指示区域气候环境变化值得商榷。
Using the grain size data of the surface sediment of two blowouts and three vertical profiles of the dunes behind the blowouts in the HulunBuir Sandy Land,we discussed the development process of dune profile behind the blowout and the reasons of the aeolian sand grain size variations in the sedimentary profiles.The results show that the grain size of the surface sediments of the blowouts and each layer of the sedimentary profiles is dominant by fine sand and medium sand;the sediment average grain size on the surface of the blowouts present fluctuant variation at different location of the blowouts;and the modern soil on the flat grassland and the bottom soil of the sedimentary profile of the dune behind the blowout are the same layer.From the comprehensive analysis of the grain size and the dune movement process,this paper argues that the variation of grain size parameters of the aeolian sand of the profiles is mainly due to the variation of profile＇s relative position caused by the moving and depositing process of the sand dune behind the blowout;and the variation of granularity characteristics of the aeolian sand of the profile obtained from the 2 cm intervals sampling whether cloud directly reflect the evolution of the regional climate environment is a debatable issue.
作者
周炎广
陈惠中
管超
李红悦
祁兴芬
哈斯额尔敦
Zhou Yanguang;Chen Huizhong;Guan Chao;Li Hongyue;Qi Xingfen;Hasi Eerdun(School of Natural Resources,Faculty of Geographical Science,Beijing Normal University,Beijing 100875,China;Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 730000,China)
出处
《中国沙漠》
CSCD
北大核心
2018年第4期724-733,共10页
Journal of Desert Research
基金
国家重点研发计划课题(2016YFC0500805)
国家自然科学基金项目(41671002)
关键词
呼伦贝尔沙地
粒度特征
风成沙
沉积物
Hulun Buir Sandy Land
grain size characteristic
aeolian sand
sediment
