策勒河下游风积地貌沉积物粒度特征及沙源分析  

Grain size characteristics and sand source analysis of three aeolian landforms in the lower reaches of the Qira River floodplain

作　　者：李鑫鑫 毛东雷[1,2] 来风兵 薛杰[3,4] 何强强 马玉娇[1,2] LI Xinxin;MAO Dongei;LAI Fengbing;XUE Jie;HE Qiangqiang;MA Yujiao(College of Geography and Tourism,Xinjiang Normal University,Urumqi 830054,Xinjiang,China;Xinjiang Key Laboratory of Lake Environment and Resources in Arid Region,Urumqi 830054,Xinjiang,China;State Key Laboratory of Desert and Oasis Ecology,Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Urumqi 830011,Xinjiang,China;Cele National Station of Observation and Research for Desert-Grassland Ecosystems,Cele 848300,Xinjiang,China)

机构地区：[1]新疆师范大学地理科学与旅游学院,新疆乌鲁木齐830054 [2]新疆干旱区湖泊环境与资源重点实验室,新疆乌鲁木齐830054 [3]中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室,新疆乌鲁木齐830011 [4]新疆策勒荒漠草地生态系统国家野外科学观测研究站,新疆策勒848300

出　　处：《干旱区研究》2024年第8期1413-1422,共10页Arid Zone Research

基　　金：国家自然科学基金地区基金项目(42061003)。

摘　　要：沉积物的粒度特征记载了丰富的环境变化信息,对研究沙漠治理和荒漠化防治具有重要意义。运用粒度分析、粒级-标准偏差法和Sahu成因判别等研究方法进行分析,研究了不同风积地貌沉积物粒度特征和沉积环境的稳定性。结果表明:(1)新月形沙丘、灌丛沙丘和低裸平沙地表层沉积物均以中砂、细砂、极细砂为优势粒级,新月形沙丘表层沉积物平均粒径最粗,为270.42μm,灌丛沙丘表层沉积物平均粒径最细,为95.60μm。(2)三种地貌类型沉积物分选性较差,占比分别为74.47%、90.47%和66.7%,新月形沙丘表层沉积物呈现负偏分布、中等峰态,灌丛沙丘和低裸平沙地表层沉积物呈现对称分布、中等峰态和窄峰态。(3)三种不同风积地貌环境敏感组分集中在22.4~399μm之内,该组分对气候变化较为敏感,更能反应沉积环境的变化,表明该区域风沙活动强烈,沉积环境主体为风成沉积环境。(4)灌丛沙丘表层沉积物完全属于风成环境沉积,新月形沙丘和低裸平沙地表层沉积物既有风成环境沉积,又有河流环境沉积。The grain size characteristics of sediments provide extensive information on environmental change,which is of great importance for the study of desert management and for preventing desertification.The grain size characteristics and sedimentary environment stability of different aeolian landforms were studied using grain size analysis,the grain size-standard deviation method,and Sahu genetic discrimination.The results show that:(1)The surface sediments of barcrescent dune s,scrub dunes,and low bare flat sand are dominated by medi-um sand,fine sand,and extremely fine sand.The surface sediments were coarsest in barcrescent dunes and small-est in scrub dunes,with average grain sizes of 270.42µm and 95.60µm,respectively.(2)The sediment sorting of the three geomorphic types was poor,with proportions of 74.47%,90.47%and 66.7%,respectively.The surface sediments of barcrescent dunes have a negatively skewed distribution and medium peak state,whereas the sur-face sediments of scrub dunes and low bare flat sand have a symmetrical distribution,medium peak state,and nar-row peak state.(3)The environmentally sensitive components of the three different aeolian landforms were con-centrated in the size range from 22.4-399µm,which is more sensitive to climate change and therefore more able to reflect changes in the sedimentary environment,indicating that the aeolian sedimentary environment is mainly dominated by aeolian sedimentary environment.(4)The surface sediments of scrub dunes were found wholly in the aeolian environment,and the surface sediments of barchan dunes and low bare flat sand were found in both aeolian and fluvial environments.

关 键 词：灌丛沙丘 新月形沙丘 低裸平沙地 沉积物 粒度特征 

分 类 号：P931.3[天文地球—自然地理学] P512.2