策勒绿洲-沙漠过渡带不同沙丘的沉积物粒度特征及沉积环境  

Sediment Granularity Characteristics and Deposition Environment of Different Dunes in the Cele Oasis-Desert Ecotone

作　　者：何强强 毛东雷[1,2] 徐佳瑞 张凯丽 刘蕾 杨郭程 HE Qiangqiang;MAO Donglei;XU Jiarui;ZHANG Kaili;LIU Lei;YANG Guocheng(School of Geography and Tourism,Xinjiang Normal University,Urumqi 830054,China;Xinjiang Laboratory of Lake Environment and Resources in Arid Zone,Urumqi 830054,China)

机构地区：[1]新疆师范大学地理科学与旅游学院,乌鲁木齐830054 [2]新疆干旱区湖泊环境与资源重点实验室,乌鲁木齐830054

出　　处：《水土保持研究》2023年第3期135-145,共11页Research of Soil and Water Conservation

基　　金：教育部人文社会科学研究规划资助项目(18YJAZH064);新疆师范大学人文社会科学重点研究基地丝绸之路经济带城市发展研究中心招标项目(XJNURWJD2019A06);新疆师范大学“十三五”校级重点学科地理学招标项目(17SDKD0701);新时代党的治疆方略与实践研究课题(2021ZJFLY36)。

摘　　要：[目的]通过对策勒绿洲-沙漠过渡带不同沙丘类型下风沙沉积物粒度、磁化率分布特征及环境敏感粒级组分进行分析,探讨不同沙丘类型下风沙沉积物相关参数及分布规律。[方法]基于绿洲-沙漠过渡带4种沙丘各部位粒度数据及磁化率数据,采用数理统计方法进行相关性分析。[结果]4种沙丘在不同地貌部位表层的沙物质粒级含量有所差别,回涡、灌丛、新月形及风影沙丘表面沙物质主要由极粗粉砂、极细砂、细砂组成,百分含量总和由小到大依次为96.71%,97.54%,98.48%,98.65%。4种不同沙丘表面沙物质分选性均为分选中度好。不同沙丘的峰态平均值介于0.93~1.02,属于中等峰态,从总体上分析4种沙丘的峰态值从迎风坡底到顶部逐渐增大,顶部到背风坡底部逐渐减小。新月形沙丘偏度值最小,偏度值介于-0.03~0.01,主要表现为对称,风影、回涡及灌丛沙丘偏度值介于-0.04~0.44,为对称和正偏。风影、灌丛及新月形沙丘表面沙物质平均粒径与偏度值呈极显著正相关(p<0.01),表明沙粒平均粒径愈粗愈趋向正偏。风影、回涡及新月形沙丘表面沙物质偏度与峰态呈极显著正相关(p<0.01),沙物质分选性愈差,就愈趋于窄峰态。通过沉积环境判别得出沉积物为风成沙,主体为风成沉积环境,4种不同的沙丘环境敏感粒级组分集中于100~570μm,表明研究区域风沙活动强烈。由于地理要素所组成的差异化构造及人为原因,导致每个不同地貌部位表面沉积物的粒级-标准偏差值相对变化差异较大。[结论]绿洲-沙漠过渡带4种风积地貌沙物质粒径差异主要是由地形、风况及沙源沉积物结构所导致。[Objective]The distribution characteristics of particle size,magnetic susceptibility and environmentally sensitive grain size fractions of eolian sand sediments under different dune types in the oasis-desert ecotone were studied to explore the relevant parameters and distribution patterns of eolian sand sediments under different dune types.[Methods]Based on the grain size data and susceptibility data of each part of the four kinds of sand dunes in the oasis-desert ecotone,the correlation analysis was carried out by using mathematical statistical method.[Results]The surface sand contents of the four types of dunes differ in different geomorphic areas,with the surface sand content of the four types of dunes consisting mainly of very coarse silty sand,very fine sand and fine sand,with the total percentage content of 96.71%,97.54%,98.48%and 98.65%,respectively.All the four different dunes have moderately good sortability of surface sand material.The mean kurtosis values of the different dunes range from 0.93 to 1.02,which is a medium kurtosis.In general,the kurtosis values of the four dunes increase gradually from the bottom to the top of the windward slope and decrease from the top to the bottom of the leeward slope.The crescent-shaped dunes have the lowest kurtosis values,ranging from-0.03 to 0.01,which are mainly symmetrical,while kurtosis values of the wind shadow,gyre and scrub range from-0.04 to 0.44,which are mainly symmetrical and positively skewed.The mean grain sizes of sand material on the surface of wind shadow dunes,scrub dunes and crescent dunes show the highly significant positive correlation(p<0.01)with the skewness value,indicating that the coarser the mean grain size is,the more positive the skewness tends to be.A highly significant positive correlation(p<0.01)is found between the skewness and kurtosis of the sand material on the surface of the wind-shaded,scrub and crescent dunes,indicating that the poorer the sand material sorting is,the more narrowly kurtotic the sand material tends to be.The fou

关 键 词：绿洲-沙漠过渡带 沉积环境 粒度特征 磁化率 沙丘 策勒 

分 类 号：P931.3[天文地球—自然地理学]