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Poisonous Plants of the Karakalpak Part of the Ustyurt Plateau (Uzbekistan)
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作者 Aymuratov Rapat Abduraimov Ozodbek +2 位作者 Shomurodov Habibullo Abduraimov Azizbek Adilov Bekzod 《American Journal of Plant Sciences》 CAS 2024年第2期83-94,共12页
The article presents the composition and current state of poisonous plants distributed on the Ustyurt plateau. Ustyurt is one of the largest deserts in Central Asia, differing from other deserts of the world in geogra... The article presents the composition and current state of poisonous plants distributed on the Ustyurt plateau. Ustyurt is one of the largest deserts in Central Asia, differing from other deserts of the world in geographical location, relief, flora and fauna and other features. The territory of Ustyurt occupies 21.3 million hectares, of which the Karakalpak part accounts for 7.2 million hectares. Poisonous alkaloid-bearing plants of the Karakalpak part of the Ustyurt plateau Anabasis aphylla, Atriplex flabellum, Kalidium capsicum, Salsola arbusculaeformis, Salsola foliosa, Aellenia subaphylla, Anabasis brachiata, Rheum tataricum, Capparis spinosa, Glycyrrhiza aspera. Alkaloid-bearing plants that are not eaten or poorly eaten by cattle Ephedra distachya, Delphinium songaricum, Anabasis salsa, alkaloid-bearing plants eaten by animals without harm Carex physodes, Eremopyrum orientale, Agrophyllum repens, Astragalus amodendron, Astragalus villosissimus, species of the genera Calligonum, Salsola. Poisonous plants of the Karakalpak part of the Ustyurt plateau. An analysis of the pasture flora of the Karakalpak part of the Ustyurt plateau shows that 62 species of wild poisonous plants belonging to 49 genera and 19 families grow here. Although these plants are considered poisonous, but in modern pharmaceutics and medicine, they are used as medicinal. 展开更多
关键词 Ustyurt plateau SPECIES Poisonous desert Climate Change
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Monitoring desertification processes in Mongolian Plateau using MODIS tasseled cap transformation and TGSI time series 被引量:3
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作者 LIU Qingsheng LIU Gaohuan HUANG Chong 《Journal of Arid Land》 SCIE CSCD 2018年第1期12-26,共15页
Most remote sensing studies assess the desertification using vegetation monitoring method. But it has the insufficient precision of vegetation monitoring for the limited vegetation cover of the desertification region.... Most remote sensing studies assess the desertification using vegetation monitoring method. But it has the insufficient precision of vegetation monitoring for the limited vegetation cover of the desertification region. Therefore, it offers an alternative approach for the desertificafon research to assess sand dune and sandy land change using remote sensing in the desertification region. In this study, the indices derived from the well-known tasseled cap transformation (TCT), tasseled cap angle (TCA), disturbance index (DI), process indicator (PI), and topsoil grain size index (TGSI) were integrated to monitor and assess the desertification at the thirteen study sites including sand dunes and sandy lands distributed in the Mongolian Plateau (MP) from 2000 to 2015. A decision tree was used to classify the desertification on a regional scale. The average overall accuracy of 2000, 2005, 2010 and 2015 desertification classification was higher than 90%. Results from this study indicated that integration of the advantages of TCA, DI and TGSI could better assess the desertification. During the last 16 years, Badain Jaran Desert, Tengger Desert, and Ulan Buh Desert showed a relative stabilization. Otindag Sandy Land and the deserts of Khar Nuur, Ereen Nuur, Tsagan Nuur, Khongoryn Els, Hobq, and Mu Us showed a slow increasing of desertification, whereas Bayan Gobi, Horqin and Hulun Buir sandy lands showed a slow decreasing of desertification. Compared with the other 11 sites, the fine sand dunes occupied the majority of the Tengger Desert, and the coarse sandy land occupied the majority of the Horqin Sandy Land. Our findings on a three or four years' periodical fluctuated changes in the desertification may possibly reflect changing precipitation and soil moisture in the MR Further work to link the TCA, DI, TGSI, and PI values with the desertification characteristics is recommended to set the thresholds and improve the assessment accuracy with field investigation. 展开更多
关键词 desertIFICATION MODIS desert sand dune sandy land Mongolian plateau
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Groundwater characteristics and climate and ecological evolution in the Badain Jaran Desert in the southwest Mongolian Plateau 被引量:1
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作者 Zhe Wang Li-juan Wang +5 位作者 Jian-mei Shen Zhen-long Nie Ling-qun Meng Le Cao Shi-bo Wei Xiang-feng Zeng 《China Geology》 2021年第3期421-432,共12页
The Badain Jaran Desert is the third largest desert in China,covering an area of 50000 km2.It lies in Northwest China,where the arid and rainless natural environment has a great impact on the climate,environment,and h... The Badain Jaran Desert is the third largest desert in China,covering an area of 50000 km2.It lies in Northwest China,where the arid and rainless natural environment has a great impact on the climate,environment,and human living conditions.Based on the results of 1∶250000 regional hydrogeological surveys and previous researches,this study systematically investigates the circulation characteristics and resource properties of the groundwater as well as the evolution of the climate and ecological environment since the Quaternary in the Badain Jaran Desert by means of geophysical exploration,hydrogeological drilling,hydrogeochemistry,and isotopic tracing.The results are as follows.(1)The groundwater in the Badain Jaran Desert is mainly recharged through the infiltration of local precipitation and has poor renewability.The groundwater recharge in the desert was calculated to be 1.8684×10^(8)m^(3)/a using the water balance method.(2)The Badain Jaran Desert has experienced four humid stages since the Quaternary,namely MIS 13-15,MIS 5,MIS 3,and the Early‒Middle Holocene,but the climate in the desert has shown a trend towards aridity overall.The average annual temperature in the Badain Jaran Desert has significantly increased in the past 50 years.In detail,it has increased by about 2.5℃,with a higher rate in the south than in the north.Meanwhile,the precipitation amount has shown high spatial variability and the climate has shown a warming-drying trend in the past 50 years.(3)The lakes in the hinterland of the Badain Jaran Desert continuously shrank during 1973‒2015.However,the vegetation communities maintained a highly natural distribution during 2000‒2016,with the vegetation cover has increased overall.Accordingly,the Badain Jaran Desert did not show any notable expansion in that period.This study deepens the understanding of groundwater circulation and the climate and ecological evolution in the Badain Jaran Desert.It will provide a scientific basis for the rational exploitation of the groundwater resources and the ecological protection and restoration in the Badain Jaran Desert. 展开更多
关键词 desert groundwater Water resource assessment Ecological environment Hydrogeological survey engineering Badain Jaran desert Alxa Right Banner SOUTHWEST Mongolian plateau China
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Monitoring rock desert formation caused by two different origins(ice-snow melting and drying)in the Qinghai-Tibet Plateau of China by considering topographic and meteorological elements
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作者 JIA Wei SHI Peijun +3 位作者 WANG Jing'ai MA Weidong XIA Xingsheng ZHOU Yuantao 《Journal of Arid Land》 SCIE CSCD 2022年第8期849-866,共18页
Monitoring rock desert formation caused by two different origins(ice-snow melting and drying)through remote sensing is crucial to our understanding of the interaction between the underlying surface of different rock d... Monitoring rock desert formation caused by two different origins(ice-snow melting and drying)through remote sensing is crucial to our understanding of the interaction between the underlying surface of different rock desert and land-atmosphere types,as well as the relationship between bare land and soil erosion.A number of achievements have been made in remote sensing monitoring of desert areas,but there is a lack of accurate classification and remote sensing identification of rock desert types based on formation mechanism.In this study,the north and south sides of the eastern Kunlun Mountains in the northern part of the Qinghai-Tibet Plateau of China were taken as the study areas.Landsat operational landscape imager,digital elevation model,and precipitation and temperature grid data were used as data sources.By identifying the bare areas based on the normalized difference vegetation index(NDVI),we used the multi-element fusion method of contours,isotherms,and isohyets to identify the rock desert types in the ice-snow melting and dry areas.The results showed that:(1)the rock desert areas identified by remote sensing based on topographic and meteorological elements were highly accurate,with an overall accuracy of 88.45%and kappa coefficient of 0.77.The multi-element fusion method of contours,isotherms,and isohyets could effectively identify the rock desert types in the ice-snow melting and dry areas;(2)the optimal segmentation range of the ice-snow melting and dry areas was 3600 m contour,-2°C-2°C isotherms,and 100-130 mm isohyets.The areas with elevation less than 3600 m,annual average temperature higher than 2°C,and average annual precipitation less than 100 mm were rock desert in the dry areas.The range of-2°C-2°C isotherms and 100-130 mm isohyets was the transition area between the ice-snow melting and dry areas.The areas with elevation higher than 3600 m,annual average temperature less than-2°C,and average annual precipitation higher than 130 mm were rock desert in the ice-snow melting areas;and(3)the identification accuracy of the bare areas based on the NDVI method was better,specifically,the identification accuracy of plain bare areas was generally better than that of mountain bare areas.The remote sensing identification method considers not only the topographic factors that have great influence on the spatial distribution of the two types of rock desert areas,but also the meteorological factors,which can provide a scientific reference for the effective identification of the two types of rock desert areas. 展开更多
关键词 rock desert in the ice-snow melting areas rock desert in the dry areas CONTOURS isotherms isohyets Qinghai-Tibet plateau
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Desert-steppe migration on the Loess Plateau at about 450 kaBP
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作者 ZHAOJingbo 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期115-122,共8页
According to the field investigation, observation by an electronic microscope and x-ray identification and chemical analysis, desert-steppe migration in the Loess Plateau at about 450 kaBP was studied. The data show t... According to the field investigation, observation by an electronic microscope and x-ray identification and chemical analysis, desert-steppe migration in the Loess Plateau at about 450 kaBP was studied. The data show that gypsum illuvial horizon indicating the desert-steppe environment developed in the early stage of the formation of the fifth layer loess in Shaoling tableland in Chang'an and Bailu tableland in Xi'an of Shaanxi are situated in the southern Loess Plateau. This indicates that remarkable drying occurred, a large-scope migration of desert steppe took place toward south and the climate zone migrated 5 degrees in latitude to south which is the largest migration range indicated by geochemical indexes. The desert-steppe and more wild environment distributed widely on the Loess Plateau at that time. The development of gypsum also indicates that the climate changed at 450 kaBP from monsoon climate to nonmonsoon climate in the Loess Plateau, and the region was not affected by summer monsoon and was in the cold and dry environment of nonmonsoon climate. Annual mean precipitation was about 200 mm, 400 mm less at that time than at present. 展开更多
关键词 the Loess plateau GYPSUM arid climate large-scale migration of desert-steppe
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黄土高原靖边剖面岩石磁学性质及其古环境意义
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作者 董良 沈中山 邓成龙 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2024年第8期3060-3074,共15页
中国黄土在东亚第四纪气候环境变化研究领域占有重要地位,靖边黄土剖面位于黄土高原北部边缘,对东亚季风变化敏感.本文对靖边黄土剖面进行了详细的岩石磁学和环境磁学研究.剖面沉积物中的主要磁性矿物为磁铁矿、磁赤铁矿以及赤铁矿,黄... 中国黄土在东亚第四纪气候环境变化研究领域占有重要地位,靖边黄土剖面位于黄土高原北部边缘,对东亚季风变化敏感.本文对靖边黄土剖面进行了详细的岩石磁学和环境磁学研究.剖面沉积物中的主要磁性矿物为磁铁矿、磁赤铁矿以及赤铁矿,黄土中的碎屑磁铁矿普遍经历了低温氧化作用的初始阶段,形成磁赤铁矿外壳包裹磁铁矿内核的结构,导致矫顽力大幅增加.磁化率随温度变化曲线(X-T)指示成壤作用生成的单畴颗粒的亚铁磁性矿物(磁铁矿和磁赤铁矿)的含量在L15(约1.25Ma)后整体减少,表明东亚夏季风强度发生阶段性减弱.黄土层中的磁化率与非磁滞磁化率比值(X/X_(ARM))与来自物源区粗粒磁性矿物含量相关,冬季风增强则X/X_(ARM)值越高,靖边剖面黄土层X/X_(ARM)在L14以后整体增加,L6以来逐渐增加,表明东亚冬季风发生过两次增强.矫正后磁化率与非磁滞磁化率((X-X_(0))/X_(ARM))指示了来自物源区磁性矿物含量,靖边剖面自2.6Ma以来,(X-X_(0))/X_(ARM)逐渐增加,源区的磁性矿物含量增多表明冬季风逐渐增强.非磁滞剩磁与饱和等温剩磁中值退磁场比值(MDF_(ARM)/MDF_(SIRM))与样品相关,样品磁性矿物粒度越粗,低温氧化作用越弱,矫顽力越高,MDF_(ARM)/MDF_(SIRM)越高,靖边剖面MDF_(ARM)/MDF_(SIRM)分别在L14和L6后整体升高,表明磁性矿物粒度整体变粗,代表了沙漠两次向南扩张.综上磁学参数一致表明,靖边黄土剖面有效地记录了东亚季风演化过程,对研究亚洲内陆干旱环境演变有重要意义. 展开更多
关键词 黄土高原 靖边剖面 岩石磁学 环境磁学 东亚季风 沙漠扩张
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Ministry of Natural Resources Plateau Desert Area Strategic Mineral Exploration and Development Technology Innovation Center Opening Ceremony
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《China Nonferrous Metals Monthly》 2024年第1期8-8,共1页
In Middle December,Plateau Desert Area Strategic Mineral Exploration and Development Technology Innovation Center of Ministry of Natural Resources was officially opened in Xining,Qinghai.The Center was co-applied and ... In Middle December,Plateau Desert Area Strategic Mineral Exploration and Development Technology Innovation Center of Ministry of Natural Resources was officially opened in Xining,Qinghai.The Center was co-applied and co-constructed by Qinghai Provincial Geological Survey Bureau,Qinghai Salt Lake Research Institute of Chinese Academy of Sciences,and Qinghai Yellow River Mining Co.,Ltd.As the first Technology Innovation Center of the Ministry of Natural Resources approved by Qinghai Provincial Natural Resources System,the Center aims to provide scientific basis for comprehensively promoting the implementation of a new round of breakthrough strategy in mineral exploration. 展开更多
关键词 plateau desert BREAKTHROUGH
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Geochemical Information Indicating the Water Recharge to Lakes and Immovable Megadunes in the Badain Jaran Desert 被引量:6
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作者 CHEN Jiansheng ZHAO Xia +3 位作者 SHENG Xuefeng WANG Jiyang GU Weizu CHEN Liang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第4期540-546,共7页
Calc-sintersdistributed in the middle of lakes and rhizoconcretions scattered at the slopes of sand dunes were observed during three explorations to the Badain Jaran Desert in the past two years. Wet sands were also f... Calc-sintersdistributed in the middle of lakes and rhizoconcretions scattered at the slopes of sand dunes were observed during three explorations to the Badain Jaran Desert in the past two years. Wet sands were also found underneath the dry surface sand layers of about 20-50 cm in thickness. The geochemical parameters were measured on minerals and water samples collected from the Badain Jaran Desert and neighboring areas. The results show that the water system in the desert may be recharged from the groundwater originating from the precipitation of the Qilian Mountains and/or the Tibetan Plateau rather than the local rainfalls. 展开更多
关键词 Badain Jaran desert isotopic compositions calc-sinter groundwater Qilian Mountains and Tibetan plateau
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Seasonal Patterns of Soil Respiration in Three Types of Communities along Grass-Desert Shrub Transition in Inner Mongolia, China 被引量:5
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作者 金钊 齐玉春 +1 位作者 董云社 Manfred DOMROES 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第3期503-512,共10页
The seasonal dynamics of soil respiration in steppe (S. bungeana), desert shrub (A. ordosica), and shrubperennial (A. ordosica +C. komarovii) communities were investigated during the growth season (May to Octo... The seasonal dynamics of soil respiration in steppe (S. bungeana), desert shrub (A. ordosica), and shrubperennial (A. ordosica +C. komarovii) communities were investigated during the growth season (May to October) in 2006; their environmental driving factors were also analyzed. In the three communities, soil respiration showed similar characteristics in their growth seasons, with peak respiration values in July and August owing to suitable temperature and soil moisture conditions during this period. Meanwhile, changes in soil respiration were greatly influenced by temperatures and surface soil moistures. Soil water content at a depth of 0 to 10 cm was identified as the key environmental factor affecting the variation in soil respiration in the steppe. In contrast, in desert shrub and shrub-perennial communities, the dynamics of soil respiration was significantly influenced by air temperature. Similarly, the various responses of soil respiration to environmental factors may be attributed to the different soil textures and distribution patterns of plant roots. In desert ecosystems, precipitation results in soil respiration pulses. Soil carbon dioxide (CO2) effluxes greatly increased after rainfall rewetting in all of the ecosystems under study. However, the precipitation pulse effect differed across the ecosystem. We propose that this may be a result of a reverse effect from the soil texture. 展开更多
关键词 soil respiration grass-desert shrub transition Stipa bungeana Artemisia ordosica Artemisiaordosica Cynanchum komarovii Ordos plateau
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THE PATTERN OF GENERAL ATMOSPHERIC CIRCULATION IN EASTERN ASIA BEFORE THE UPLIFT OF THE TIBETAN PLATEAU
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作者 Jiang Xinsheng, Pan Zhongxi, Fu Qingping (Chengdu Institute of Geology and Mineral Resources,Chinese Academy of Geological Sciences, Chengdu 610082 , China) 《地学前缘》 EI CAS CSCD 2000年第S1期399-400,共2页
The global climatic change study is a hot point today.As the pattern of the general circulation of the atmosphere is the key factor for climate,the reconstruction of the pattern of the past general circulation of the ... The global climatic change study is a hot point today.As the pattern of the general circulation of the atmosphere is the key factor for climate,the reconstruction of the pattern of the past general circulation of the atmosphere has become important part of the global climatic change study.The paleowind belts are the comprising part of the past general circulation of the atmosphere and also the records of the circulation,therefore,their reconstruction will be helpful to the reconstruction of the general circulation of the atmosphere.In present years,the pattern of the general circulation of the atmosphere has attracted great concern from scientists.For example,Zhang Linyuan and Liu Dongsheng, based on the existence and inexistence of the Tibetan Plateau and paleogeography,divide the evolution of the general circulation of the atmosphere in eastern asia into two stages:the planetary wind stage before the uplift of the plateau and the monsoon stage after the uplift of the plateau which is subdivided into ancient monsoon and modern monsoon stages.While Dong Guangrong et al., Jiang Xinsheng et al. and Cooke et al, based on the latitudinal distribution of the Cretaceous and Tertiary deserts and the generation of arid climate,suggest that there was a subtropical high pressure zone across the eastern asia and was a planetary wind system,but have not found any direct record of the circulation.It is true that before the Early Tertiary,not only organism, but also inorganism,i.e.,biogeography and lithogeography, show strong zonal distribution.It can only indicate that zonal climate was evident at that time.Of course, as the climate is the result of the influences on the ground by zones of the circulation,it is reasonable to deduce the existence of zonal circulation,i.e. the the existence of the planetary wind system,from the zonal climate.But it would be much better if direct record of planetary wind system were found.Prevailing winds are the main geological agent for a desert which must leave deep stamps on the desert.The stamps on modern desert are reflected by dune migrating directions and on paleodesert by foreset dip directions..It is the most direct geological record for reconstructing paleowind belts and has been extensively used to reconstruct paleowind belts,paleogeography,paleoclimate and even to check the paleolatitude determined by paleomagnetism (for example, Opdyke and Runcorn, 1960; Creer, 1958; Pook, 1962; Bigarella and Salamuni,1961). 展开更多
关键词 CRETACEOUS deserts REGULARITY of paleowind DIRECTIONS pat tern of paleowind BELTS UPLIFT of the Tibet plateau
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青藏高原干旱荒漠地区叶面积指数时空变化及影响因素
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作者 郭玉超 任鸿瑞 《中国水土保持科学》 CSCD 北大核心 2023年第5期38-50,共13页
探索青藏高原干旱荒漠地区植被生长状况及其影响因素,以期为该地区生态环境治理、可持续发展及环境保护提供参考。基于GLASS LAI数据,辅助气候、地形、社会等因子,采用最大值合成法、趋势分析法、变异系数法与偏相关分析法,分析1981—2... 探索青藏高原干旱荒漠地区植被生长状况及其影响因素,以期为该地区生态环境治理、可持续发展及环境保护提供参考。基于GLASS LAI数据,辅助气候、地形、社会等因子,采用最大值合成法、趋势分析法、变异系数法与偏相关分析法,分析1981—2018年青藏高原干旱荒漠地区植被叶面积指数(LAI)时空变化格局。结果表明:1)植被LAI在这38 a间呈显著增加趋势(P<0.05),有64.85%的区域趋于增长,35.15%的区域趋于退化;2)不同海拔区间植被LAI变化特征有所差异,海拔≤2000 m呈不显著降低趋势(P>0.05),海拔>2000 m均呈显著增加趋势(P<0.05),其波动程度在海拔>6000 m及海拔≤2000 m区间更高;3)植被LAI与气温、降水呈正相关区域所占比例分别为63.93%和52.72%,其中通过显著性检验区域比例分别为11.56%和4.45%,气温与降水相比对植被LAI变化影响更为显著。1981—2018年间,研究区气候逐渐向暖湿化方向转变,对植被生长产生积极影响。经济发展、人口数量上升给该区植被覆盖带来一定负面影响,体现在土地利用变化上主要显示为草地退化、未利用土地扩张的特征。 展开更多
关键词 叶面积指数 变化格局 干旱荒漠地区 青藏高原
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中国沙漠的同位素分区特征 被引量:20
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作者 杨杰东 陈骏 +2 位作者 饶文波 李高军 季峻峰 《地球化学》 CAS CSCD 北大核心 2007年第5期516-524,共9页
系统采集了中国10个主要沙漠或沙地(塔克拉玛干沙漠、巴丹吉林沙漠、腾格里沙漠、柴达木沙漠、毛乌素沙漠、库布齐沙漠、古尔班通古特沙漠、浑善达克沙地、科尔沁沙地和呼伦贝尔沙地)样品,并在黄土高原西峰、环县和洛川剖面采集了马兰黄... 系统采集了中国10个主要沙漠或沙地(塔克拉玛干沙漠、巴丹吉林沙漠、腾格里沙漠、柴达木沙漠、毛乌素沙漠、库布齐沙漠、古尔班通古特沙漠、浑善达克沙地、科尔沁沙地和呼伦贝尔沙地)样品,并在黄土高原西峰、环县和洛川剖面采集了马兰黄土(L1)样品。通过选择合适的粒级和样品处理方法,对样品酸不溶物进行了Nd和Sr同位素组成的测定。测定结果表明,中国10个沙漠或沙地的Nd同位素组成εNd(0)的变化范围大,为-1.2~-17.2。根据Nd同位素组成范围,10个沙漠或沙地的εNd(0)从高到低可以分为4个区域:A1:古尔班通古特沙漠和呼伦贝尔沙地(-1.2~-4.0);A2:浑善达克沙地和科尔沁沙地(-4.4~-7.0);B:塔克拉玛干沙漠、柴达木沙漠、巴丹吉林沙漠和腾格里沙漠(-7.4~-11.7);C:毛乌素沙漠和库布齐沙漠(-11.8~-17.2)。中国沙漠Nd同位素组成的分区性与中国北方的大地构造和山脉分布密切相关,并表明中国沙漠具有近源性,即沙漠物质主要来源于其邻近周围的山脉和基底岩石的风化侵蚀。通过对比,黄土高原黄土Nd和Sr同位素组成与柴达木沙漠和阿拉善高原的沙漠(腾格里和巴丹吉林沙漠)相同,而与其他沙漠不同。塔克拉玛干沙漠碳同位素组成为0.19‰~0.62‰;柴达木沙漠、巴丹吉林沙漠和黄土高原马兰黄土碳同位素组成都落在1.20‰~2.40‰之内。黄土高原马兰黄土碳同位素组成与柴达木沙漠和巴丹吉林沙漠相类似,而与塔克拉玛干沙漠不同。本次研究为Liuetal.(1996)的推论,即黄土高原黄土物质最终来源于青藏高原东北缘,提供了一个有力的同位素证据。 展开更多
关键词 沙漠 黄土 ND同位素 黄土高原 青藏高原
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黄土高原黄土物源区的同位素证据 被引量:15
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作者 杨杰东 李高军 +2 位作者 戴澐 饶文波 季峻峰 《地学前缘》 EI CAS CSCD 北大核心 2009年第6期195-206,共12页
系统采集了黄土高原马兰黄土、河西走廊和青藏高原东北部黄土、河床沙和湖泥样品。用酸淋洗去除方解石后,黄土高原马兰黄土εNd(0)值从-9.2到-11.3,87Sr/86Sr比值从0.71784到0.71944,都落在同位素B区内,与青藏高原东北部、巴丹吉林沙漠... 系统采集了黄土高原马兰黄土、河西走廊和青藏高原东北部黄土、河床沙和湖泥样品。用酸淋洗去除方解石后,黄土高原马兰黄土εNd(0)值从-9.2到-11.3,87Sr/86Sr比值从0.71784到0.71944,都落在同位素B区内,与青藏高原东北部、巴丹吉林沙漠和腾格里沙漠的值一致。黄土高原马兰黄土白云石的δ13C值从1.2‰到1.5‰,与青藏高原东北部和河西走廊黄土,巴丹吉林沙漠的白云石的值类似。这些表明青藏高原东北部、巴丹吉林沙漠和腾格里沙漠可能是黄土高原黄土的源区,从而排除了其他沙漠(古尔班通古特沙漠、塔克拉玛干沙漠、毛乌素沙漠、库布齐沙漠、浑善达克沙地、科尔沁沙地和呼伦贝尔沙地)作为黄土物源区的可能性。同位素研究结果和野外调查进一步揭示,黄土高原黄土、巴丹吉林沙漠和腾格里沙漠物质可能最终都是来源于青藏高原东北部。 展开更多
关键词 同位素 黄土 沙漠 中国黄土高原 青藏高原
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鄂尔多斯沙漠高原湖淖群的形成演化及生态功能探讨 被引量:17
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作者 黄金廷 王文科 +3 位作者 何渊 王钊 乔冈 马雄德 《资源科学》 CSSCI CSCD 北大核心 2006年第2期140-146,共7页
湖淖群是鄂尔多斯沙漠高原的重要组成部分,有维持湖滨的植物群落生长、缓和湖泊流域的气候变化、维持生物多样性等作用,具有重要的生态功能。本文从湖淖的形成和补给来源出发,分析了湖淖的特点。从新构造运动、气候变化和人类活动等方... 湖淖群是鄂尔多斯沙漠高原的重要组成部分,有维持湖滨的植物群落生长、缓和湖泊流域的气候变化、维持生物多样性等作用,具有重要的生态功能。本文从湖淖的形成和补给来源出发,分析了湖淖的特点。从新构造运动、气候变化和人类活动等方面研究了区内湖淖群的演化。研究表明,近年来受气候干旱和人类活动的影响,区内地下水位下降,湖淖补给量减小,是湖淖水域萎缩、生态功能减退的主要原因。这为进一步研究鄂尔多斯高原湖淖群的作用及保护生态环境提供了科学依据。 展开更多
关键词 湖群演化 生态功能 地下水 部尔多斯沙漠高原
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蒙古中南部地区的上地幔P波速度结构 被引量:11
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作者 张风雪 吴庆举 +4 位作者 李永华 高孟潭 Ulziibat Munkhuu Sukhbaatar Usnikh Demberel Sodnomsambuu 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2014年第9期2790-2801,共12页
利用中蒙国际科技合作专项项目在蒙古中南部地区布设的69个宽频带地震仪在2011年8月—2013年7月所记录的远震波形数据,采用波形相关方法在0.02-0.1 Hz的频段内拾取了18551个有效的P震相相对走时残差数据,进一步采用有限频走时层析成像... 利用中蒙国际科技合作专项项目在蒙古中南部地区布设的69个宽频带地震仪在2011年8月—2013年7月所记录的远震波形数据,采用波形相关方法在0.02-0.1 Hz的频段内拾取了18551个有效的P震相相对走时残差数据,进一步采用有限频走时层析成像的方法,反演获取了蒙古中南部下方深达800 km的P波速度结构.结果显示:肯特山下方的低速异常极有可能是推测中的肯特山地幔柱的反映;呼斯坦瑙鲁和曼达尔戈壁西边的低速异常可能与杭爱山高原下的地幔柱或地幔对流有关联;戈壁滩的低速异常带可能和达里甘嘎火山有相同的热来源。可能是该区火成岩存在的深部原因,也可能是戈壁滩及其周边地区地幔柱或下地幔热物质上涌的表现. 展开更多
关键词 蒙古 层析成像 杭爱山高原 肯特山 戈壁滩
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中更新世全球最大冰期与中国沙漠扩张 被引量:19
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作者 邬光剑 潘保田 +1 位作者 管清玉 高红山 《冰川冻土》 CSCD 北大核心 2002年第5期544-549,共6页
位于青藏高原和西北干旱区交界带的沙沟黄土剖面 ,详细记录了 0 8MaBP以来东亚季风系统和沙漠演化的历史 .L6黄土层中 ,中值粒径和砂粒含量表明当时冬季风极端强盛 ,沙漠大规模扩张 ,其范围仅次于末次冰期最盛期 .在 0 6~ 0 7MaBP以... 位于青藏高原和西北干旱区交界带的沙沟黄土剖面 ,详细记录了 0 8MaBP以来东亚季风系统和沙漠演化的历史 .L6黄土层中 ,中值粒径和砂粒含量表明当时冬季风极端强盛 ,沙漠大规模扩张 ,其范围仅次于末次冰期最盛期 .在 0 6~ 0 7MaBP以前 (即深海氧同位素MIS16阶段 ) ,北半球高纬度大陆冰盖大规模扩展 ,全球冰量达到最大 ,并且西伯利亚冰盖的扩展 ,还使得西伯利亚高压增强 ;同时 ,青藏高原上也发育了最大规模的冰川 ,从而强化了西风和东亚冬季风 .其结果造成了中国季风边缘区的沙漠扩张 .虽然全球冰量和青藏高原是影响沙漠演化的重要因素 ,但在不同的时段其机制可能有所不同 ,也不能忽略其它因素的影响 . 展开更多
关键词 青藏高原 最大冰期 黄土 沙漠演化 大陆冰盖 粒度
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荒漠植物沙鞭(Psammochloa villosa)种质资源收集及谱系遗传分化初探 被引量:9
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作者 吕婷 刘玉萍 +3 位作者 周勇辉 刘涛 张晓宇 苏旭 《草地学报》 CAS CSCD 北大核心 2018年第3期733-740,共8页
沙鞭(Psammochloa villosa)是禾本科(Poaceae)、针茅族(Stipeae)、沙鞭属(Psammochloa)中一个具有重要经济和生态价值的荒漠特有种,具有较强的抗逆性,是一种优质防风固沙植物,主要分布于内蒙古高原及其毗邻沙地。2013-2016年,本研究调... 沙鞭(Psammochloa villosa)是禾本科(Poaceae)、针茅族(Stipeae)、沙鞭属(Psammochloa)中一个具有重要经济和生态价值的荒漠特有种,具有较强的抗逆性,是一种优质防风固沙植物,主要分布于内蒙古高原及其毗邻沙地。2013-2016年,本研究调查了沙鞭野生种质资源在内蒙古高原及其毗邻地区的自然地理分布,并在群体水平上收集了凭证标本、DNA材料和成熟种子;同时,从采集材料中选取具有代表性的180个个体进行了nrITS序列的扩增和测序,结果发现沙鞭所有参试种群的nrITS序列存在两个较为明显的谱系遗传分支,即一个分支主要由生长于内蒙古高原东部的所测个体组成,另一个分支由内蒙古高原西部的所测个体构成,这与依据外部形态特征和叶表皮微形态特征鉴分的结果相吻合。此外,本文还进一步讨论了这些丰富的种质资源对今后研究和利用沙鞭的重要性和相关途径。 展开更多
关键词 内蒙古高原 沙鞭 荒漠植物 种质资源
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青藏高原东缘古近纪沙漠及其对季风起源的启示 被引量:15
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作者 江新胜 崔晓庄 +4 位作者 伍皓 熊国庆 卓皆文 陆俊泽 江卓斐 《沉积与特提斯地质》 CAS CSCD 2012年第3期54-63,共10页
沙漠沉积是地质历史演化过程中的一种特殊沉积,是特殊气候条件下的产物,对研究全球气候变化、大气环流样式具有独特的作用。沙漠沉积在地质历史中普遍存在但极少保存,它的发现和研究对恢复地质历史具有重要意义。研究表明,现代东亚季风... 沙漠沉积是地质历史演化过程中的一种特殊沉积,是特殊气候条件下的产物,对研究全球气候变化、大气环流样式具有独特的作用。沙漠沉积在地质历史中普遍存在但极少保存,它的发现和研究对恢复地质历史具有重要意义。研究表明,现代东亚季风系统建立前,尤其是古近纪早、中期,青藏高原东缘仍然处于行星环流所控制的干旱带内,发育了大量代表干旱炎热气候的石膏与盐类沉积,但至今尚未找到沙漠存在的确切记录。近年来,笔者采用沉积学、古气候学、古地理学等手段,并结合前人研究资料,对青藏高原东缘沉积盆地的古近纪早、中期红色地层进行了综合研究。结果表明,青藏高原东缘存在一个厚度稳定的古近纪早、中期风成沙丘富集带。在此基础上,通过古地理、沉积模式及古气候替代指标等分析,论证了青藏高原东缘存在古近纪盆山型沙漠沉积体系的可能性。沉积相、古流向分析揭示,青藏高原东缘存在一个由干旱向潮湿、由行星风系向季风风系转换的界面,可能暗示了东亚季风建立事件的发生。本研究相关成果可为新生代中国干旱带演化与全球气候变化研究提供可贵的沉积学资料,也可为青藏高原隆升与东亚季风起源研究提供重要的大气环流证据。 展开更多
关键词 青藏高原东缘 古近纪 沙漠 古气候 季风起源
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鄂尔多斯沙漠高原白垩系地下水水化学演化的多元统计分析 被引量:30
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作者 吴春勇 苏小四 +1 位作者 郭金淼 董维红 《世界地质》 CAS CSCD 2011年第2期244-253,共10页
结合稳定同位素(D1、8O1、3C),应用聚类分析和因子分析两种多元统计分析方法,对鄂尔多斯沙漠高原白垩系含水层地下水水化学演化特征进行研究。结果表明:研究区环河组和洛河组地下水均可分为3大类,且大致在地下水补给区、径流区和排泄区... 结合稳定同位素(D1、8O1、3C),应用聚类分析和因子分析两种多元统计分析方法,对鄂尔多斯沙漠高原白垩系含水层地下水水化学演化特征进行研究。结果表明:研究区环河组和洛河组地下水均可分为3大类,且大致在地下水补给区、径流区和排泄区分别聚类,每一类的水化学特征和同位素特征均存在一定的差异;研究区地下水均起源于大气降水,发生了岩盐溶滤、碳酸盐矿物溶解、硫酸盐矿物溶解、硅酸盐矿物溶解和阳离子交换等水文地球化学作用。相对洛河组地下水,环河组地下水水化学演化特征还受到了大气降水稀释作用和酸碱演化的影响。 展开更多
关键词 鄂尔多斯沙漠高原 白垩系含水层 水化学演化 聚类分析 因子分析 地下水
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荒漠植被红砂(Reaumurta soongorica)水热响应的年轮学研究 被引量:30
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作者 肖生春 肖洪浪 +2 位作者 宋耀选 段争虎 陆明峰 《中国沙漠》 CSCD 北大核心 2006年第4期548-552,共5页
红砂是黄土高原荒漠植被带主要建群植物种之一,在植被恢复重建和生态建设中具有重要意义。本文以皋兰县40 a天然植被封育区为例,运用树木年轮学方法,对不同坡向红砂与当地水热条件变化的时空响应及分布格局进行了研究。研究结果表明,红... 红砂是黄土高原荒漠植被带主要建群植物种之一,在植被恢复重建和生态建设中具有重要意义。本文以皋兰县40 a天然植被封育区为例,运用树木年轮学方法,对不同坡向红砂与当地水热条件变化的时空响应及分布格局进行了研究。研究结果表明,红砂具有明显的年轮特征,可以进行树木年轮方面的研究。虽然不同坡向水分条件和植被状况有很大差异,但红砂径向生长对区域水热变化具有非常一致的响应模式:同生长季降水呈正相关关系,尤以7月降水量最为显著;同生长季气温呈负相关关系,以6月最为显著。根据不同坡向红砂年龄分布格局分析结果,并考虑到水土流失的防治效果,黄土高原西部荒漠植被带的封育期限不宜少于10 a。 展开更多
关键词 红砂 灌木树木年轮学 水热变化 荒漠植被带 植被恢复 黄土高原
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