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Journal of Arid Land 2015年第1期7卷 1-9页

作者： Zhi ZHANG ZhiBao DONG ChangZhen YAN GuangYin HU Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Understanding the relationship between the changes in lake water volume and climate change can provide valuable information to the recharge sources of lake water. This is particularly true in arid areas such as the Badain Jaran Sand Sea, an ecologically sensitive area, where the recharge sources of lakes are heatedly debated. In this study, we determined the areas of 50 lakes （representing 70% of the total permanent lakes in this sand sea） in 1967, 1975, 1990, 2000 and 2010 by analyzing remote-sensing images using image processing and ArGIS software. In general, the total lake area decreased from 1967 to 1990, remained almost unchanged from 1990 to 2000, and increased from 2000 to 2010. Analysis of the relationship between these changes and the contemporaneous changes in annual mean temperature and annual precipitation in the surrounding areas suggests that temperature has significantly affected the lake area, but that the influence of precipitation was minor. These results tend to su- pport the palaeo-water recharge hypothesis for lakes of the Badain Jaran Sand Sea, considering the fact that the distribution and area of lakes are closely related to precipitation and the size of mega-dunes, but the contemporaneous precipitation can hardly balance the lake water.

关键词： arid environment lake change source of water recharge climate change

Aeolian transport over a developing transverse dune

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Journal of Arid Land 2014年第3期6卷 243-254页

作者： ZhiBao DONG Ping LV ZhengCai ZHANG JunFeng LU Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

The spatial and temporal changes in aeolian transport over a dune are fundamental factors that control the morphology of the dune. In the present study, we obtained direct field observations of aeolian transport over a developing transverse dune at the Shapotou Aeolian Experiment Site in the southeastern part of China＇s Tengger Desert. The transport rate versus wind speed relationship relationships over flat surfaces and over dunes that are s complicated over a developing dune compared with the n equilibrium with the wind. We obtained trend lines for transport rate over the transverse dune versus distance. The transport rate generally increased from the toe to the crest above the stoss slope, but the difference in transport rate between the crest and the toe was smaller than those that have been proposed for taller dunes. The crest/toe ratio for transport rates therefore seems to depend greatly on dune height. Flux density profiles for different points above the dune at different wind speeds were well described by the exponential decay law, as has been proposed for saltation flux density profiles. Coefficients in the flux density profile function can be defined in terms of the transport rate and wind speed. However, the dependence of relative decay rate with height and average saltation height on wind speed was weaker than that observed in a wind tunnel and above a fiat surface. The preliminary results obtained in this study require more evidence from field observations to fully describe aeolian transport above developing dunes.

关键词： aeolian transport aeolian geomorphology dune dynamics

Grain-size characteristics of linear dunes on the northern margin of Qarhan Salt Lake, northwestern China

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Journal of Arid Land 2015年第4期7卷 438-449页

作者： LI Jiyan DONG Zhibao ZHANG Zhengcai QIAN Guangqiang LUO Wanyin LU Junfeng Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

In order to clarify the formation mechanism of linear dunes on the northern margin of Qarhan Salt Lake, northwestern China, we analyzed the grain-size and sorting parameters of the dune and interdune sands. The surface sands （0-30 ram） from the dune base to the crest of both flanks and interdune corridors were sampled along transects from upwind to downwind through the dune field. The results indicated that the grain-size distribution differed at different positions between and within the dunes. The frequency curve for dune sands mainly showed a bimodal distribution, while the interdune sediments showed a trimodal distribution. The grain size distribution of the linear dunes showed a finer crest pattern, i.e. the crests were composed of sands that were generally finer, better sorted than those of base sands. In addition, at the dune field scale, the dune crest sands were tending to become much finer but sorting became worse along the downwind transects. However, the grain-size parameters of sediments in the interdune corridors showed no clear pattern. The results demonstrated that the grain size and sorting parameters exhibited a systematic change not only at the individual scale but also at the dune field scale. Our results quantitatively estimate the limited role of cohesive sediments on the formation of linear dune under unidirectional wind regime. More attention should be paid to a long-term wind regime observation, internal sedimentary structures and their formation ages.

关键词： linear dune longitudinal dune grain-size parameters Qarhan Salt Lake Qaidam Basin

Geomorphologic patterns of dune networks in the Tengger Desert,China

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Journal of Arid Land 2016年第5期8卷 660-669页

作者： WEN Qing DONG Zhibao Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Department of Geography Shaanxi Normal University

Dune networks are widely distributed in the world＇s deserts,which include primary ridges and secondary ***,they have not been sufficiently studied in a systematic manner and their origins and spatial and morphological characteristics remain *** provide information on the geomorphology of dune networks,we analyze the software geomorphologic patterns of the dune networks in China＇s Tengger Desert using matrix and laboratory to process remote-sensing *** on analysis of image features and their layout in a topographic map,we identify two types of dune networks （square and rectangular dune networks） with different size and morphological structures in the Tengger *** important geomorphic pattern parameters,ridge length,spacing,orientation and defect density,are *** length of primary ridges of dune networks decreases from northwest of the desert to the southeast,resulting an increasing spacing and a transition from rectangular dune networks to square dune *** regime and sediment supply are responsible for the variation in pattern *** use the spacing and defect density data to estimate the construction time of dune networks and found that the dune networks in the Tengger Desert formed since about 1.3 ka BP.

关键词： aeolian geomorphology dune networks geomorphological parameters geomorphic pattern analysis Tengger Desert

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人工模拟戈壁风沙流与风程效应观测

中国科学：地球科学 2011年第8期41卷 1505-1510页

作者：张正偲董治宝赵爱国中国科学院沙漠与沙漠化重点实验室兰州730000

风程效应是研究土壤风蚀和风沙流的一个重要概念,它影响土壤风蚀和风沙流的发生发展过程.对风程效应的研究有助于进一步认识风沙运动机制,为完善风沙物理和土壤风蚀研究提供科学依据.本文选择腾格里沙漠东南缘的中国科学院风沙综合观测... 详细信息

风程效应是研究土壤风蚀和风沙流的一个重要概念,它影响土壤风蚀和风沙流的发生发展过程.对风程效应的研究有助于进一步认识风沙运动机制,为完善风沙物理和土壤风蚀研究提供科学依据.本文选择腾格里沙漠东南缘的中国科学院风沙综合观测场人工模拟戈壁为研究对象,利用多路方口集沙仪对戈壁不同风程长度的风沙流进行观测,旨在说明戈壁风程效应与风沙流的关系.研究表明,风程对风沙流通量具有明显的影响,风沙流通量的拟合系数和相对递减率均随风程增加先减小后增加.风程不同,输沙率不同,总体表现为输沙率随风程增加先增加后降低,地面以上部分最先达到最大值,风程长度为34m左右,随后降低;随高度增加,最大输沙率所对应的风程长度有增加趋势.

关键词：风程效应人工戈壁风沙流

同方期刊数据库

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降尘收集方法对降尘效率的影响

环境科学 2013年第2期34卷 499-508页

作者：张正偲董治宝中国科学院寒区旱区环境与工程研究所沙漠与沙漠化重点实验室兰州730000

大气降尘收集方法较多,但目前还没有通用的野外观测方法,由于降尘收集方法的多样性以及降尘缸收集效率的不同,所观测的结果很难进行对比.目前对各类降尘缸收集降尘效率的研究较少.在腾格里沙漠地区,利用国家标准规定降尘缸,对干法、湿... 详细信息

大气降尘收集方法较多,但目前还没有通用的野外观测方法,由于降尘收集方法的多样性以及降尘缸收集效率的不同,所观测的结果很难进行对比.目前对各类降尘缸收集降尘效率的研究较少.在腾格里沙漠地区,利用国家标准规定降尘缸,对干法、湿法、过滤网法、过滤网+玻璃球法和减速沿法这5种降尘收集方法进行对比研究,旨在探讨不同降尘收集方法的收集效率,为准确评价区域降尘量提供依据.干法收集的降尘量仅占湿法的5%～62%;减速法仅占湿法的50%～95%;过滤网法仅占湿法的43%～89%;玻璃球+过滤网法仅占湿法的40%～80%.不同的降尘收集方法,风速明显影响降尘效率,平均风速2.5 m·s-1时,降尘效率与平均风速之间无明显规律.湿法收集的降尘粒度最细,依次为减速法、玻璃球+过滤网法、过滤网法和干法.平均风速,>5 m·s-1的平均风速与湿法,减速法收集的降尘量之间可以用指数函数表示.不同降尘方法观测的数据可以相互转化,干法、过滤网、过滤网+玻璃球法、减速沿法与湿法收集的降尘量之间为线性相关.在干旱及半干旱地区,减速法能够作为一种替代湿法进行收集降尘的有效方法.

关键词：降尘降尘缸效率野外观测方法

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腾格里沙漠东南缘春季降尘量和粒度特征

中国环境科学 2011年第11期31卷 1789-1794页

作者：张正偲董治宝中国科学院寒区旱区环境与工程研究所中国科学院沙漠与沙漠化重点实验室甘肃兰州730000

根据腾格里沙漠东南缘风沙科学观测场实测的降尘资料，对该地区春季（3-5月）降尘量和降尘粒度特征进行了研究．结果表明：该地区5月的降尘量最大，其次为4月和3月．春季降尘量的平均值为1053．3kg/hm2．研究区降尘平均粒径较粗，以沙... 详细信息

根据腾格里沙漠东南缘风沙科学观测场实测的降尘资料，对该地区春季（3-5月）降尘量和降尘粒度特征进行了研究．结果表明：该地区5月的降尘量最大，其次为4月和3月．春季降尘量的平均值为1053．3kg/hm2．研究区降尘平均粒径较粗，以沙物质为主．分选性较差至很好．偏度近对称至极正偏．峰度中等至很窄．受风速、地表粗糙度和沙源的影响，降尘粒级分布既有单峰，又有双峰和三峰，主要以双峰为主，同时，所有粒径中跃移颗粒约占90％，近距离输送的悬移颗粒占7％左右，而远距离输送的悬移颗粒仅占不到4％．因此可以认为，该地区跃移颗粒的跳跃高度高于前人的研究结果．同时，在腾格里沙漠东南缘的沙漠地区，大气降尘主要以局地的沙粒为主，远源沙尘贡献并不多．

关键词：腾格里沙漠东南缘降尘量粒度

腾格里沙漠东南缘不同发育阶段横向沙丘粒度特征

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中国沙漠 2015年第1期35卷 129-135页

作者：李超董治宝崔徐甲陕西师范大学旅游与环境学院陕西西安710062 中国科学院寒区旱区环境与工程研究所中国科学院沙漠与沙漠化重点实验室甘肃兰州730000

选取了腾格里沙漠东南缘风沙观测场内经人工平整后流动沙地上出现的新生横向沙丘和观测场外围未经人工干预的原始横向沙丘,采集了其表层的沉积物进行试验分析,探讨了不同发育阶段沙丘之间和沙丘表层不同部位之间沉积物粒度组成的空间差... 详细信息

选取了腾格里沙漠东南缘风沙观测场内经人工平整后流动沙地上出现的新生横向沙丘和观测场外围未经人工干预的原始横向沙丘,采集了其表层的沉积物进行试验分析,探讨了不同发育阶段沙丘之间和沙丘表层不同部位之间沉积物粒度组成的空间差异及其所反映的近地层风沙运动过程。结果表明:腾格里沙漠东南缘横向沙丘以细沙为主(53.87%),其次为中沙(42.57%),粗沙和极细沙含量很少;新生沙丘表层沙粒的平均粒径(1.98Φ)略大于原始沙丘(2.16Φ),而分选性都很好。两类沙丘的偏度都表现为近对称,峰度都表现为中等类型;由于沙丘所处发育阶段和尺度不同,即使在同一种风能环境下,两类沙丘及其表层不同部位沙粒的粒径分布也存在明显差异。

关键词：新生沙丘原始沙丘粒度风沙流腾格里沙漠

基于自组织理论的巴丹吉林沙漠高大沙山空间分布特征研究

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中国沙漠 2015年第2期35卷 294-300页

作者：李超董治宝陕西师范大学旅游与环境学院陕西西安710062 中国科学院寒区旱区环境与工程研究所沙漠与沙漠化重点实验室甘肃兰州730000

通过最邻近距离法定量描述了巴丹吉林沙漠高大沙山空间分布特征,分析和讨论了巴丹吉林沙漠高大沙山的主要成因和影响因素。结果表明:研究区内高大沙山空间分布的均匀程度整体上呈现出由西向东逐渐增大的趋势,而东南部靠近雅布赖山地区... 详细信息

通过最邻近距离法定量描述了巴丹吉林沙漠高大沙山空间分布特征,分析和讨论了巴丹吉林沙漠高大沙山的主要成因和影响因素。结果表明:研究区内高大沙山空间分布的均匀程度整体上呈现出由西向东逐渐增大的趋势,而东南部靠近雅布赖山地区略有降低,最邻近指数R主要分布在1.29~1.63。沙山底面积和沙山绝对高度在空间上同样呈现出由西向东逐渐增大的趋势,但巴丹吉林沙漠高大沙山空间分布均匀程度的发展并不直接受到所在地海拔的影响。巴丹吉林沙漠高大沙山在空间分布上具有较高的自组织特征,而风力作用是塑造和维持巴丹吉林沙漠高大沙山巨大高度与自组织排列特征的主要力量。

关键词：巴丹吉林沙漠最邻近分析自组织空间分布

基于MATLAB平台的遥感影像沙丘脊线提取与地貌格局表征参数计算

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中国沙漠 2013年第6期33卷 1636-1642页

作者：蒋缠文董治宝文青中国科学院寒区旱区环境与工程研究所沙漠与沙漠化重点实验室甘肃兰州730000

随着现代科学技术的发展,遥感影像为区域风沙地貌形态的研究提供了可靠的资料。近年来,有地貌学者提出了沙丘地貌格局分析法,通过在遥感影像上绘制沙丘脊线,量测和计算得到沙丘地貌格局表征参数,分析沙丘概率分布和空间变化规律、影响... 详细信息

随着现代科学技术的发展,遥感影像为区域风沙地貌形态的研究提供了可靠的资料。近年来,有地貌学者提出了沙丘地貌格局分析法,通过在遥感影像上绘制沙丘脊线,量测和计算得到沙丘地貌格局表征参数,分析沙丘概率分布和空间变化规律、影响因素及形成时间。本文选取腾格里沙漠典型横向沙丘区域为研究对象,发展基于MATLAB平台的遥感影像沙丘脊线提取方法,利用沙丘迎风坡与落沙坡在遥感影像中成像的灰度差异,对沙丘的沙脊线进行提取,继而获得沙丘脊线长度、沙丘间距、走向、缺陷密度等沙丘地貌格局表征参数。结果表明,该方法快捷、可靠,为沙丘脊线的绘制提供了一种新方法。

关键词：遥感影像 MATLAB 地貌格局表征参数图像处理沙丘脊线