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同学少年 2006年第4期 35-35页

The evolution of deserts with climatic changes in China since 150 ka B.P.

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Science China Earth Sciences 1997年第4期40卷 370-382页

作者：董光荣陈惠忠王贵勇李孝泽邵亚军金炯 Institute of Desert Research Chinese Academy of Sciences Lanzhou 730000 China

According to the bioclimatic zones, dune mobility and the fabric characteristics of stratigraphic sedimentary facies, the deserts in China are divided into Eastern, Western, Central and Northwestern deserts. Based on the records of stratigraphical facies, climatic proxies, historical data, etc. in each desert region, the evolution of deserts with climatic changes in time and space since 150 ka B. P. in China are dealt with; then the evolution of deserts in relation to the glacial climatic fluctuations caused by solar radiation changes, underlying surface variation and their feedback mechanism is discussed through comparison with global records; finally, in consideration of global wanning due to increasing of greenhouse gases such as CO2, the possible tendency of the evolution of deserts and the climatic changes is discussed.

关键词： 150 ka B.P. evolution of deserts climatic change

Local Meridional Circulation and deserts

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Advances in Atmospheric Sciences 2001年第5期18卷 864-872页

作者：刘平吴国雄孙菽芬 LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

This paper investigates the dry climatology of Sahara and Northwest China deserts from the viewpoint of local meridional circulation with Xie and Arkin rainfall dada and NCAR/NCEP reanalysis data. Results show that there are very dry centers with annual rainfall less than 50 mm over these two deserts while the rainy seasons are very different. In the south part of Sahara desert center and Northwest China desert, over 70% rainfall takes place in June, July and August (JJA). While in the north part of Sahara, rainfall mainly concentrates in December, January and February (DJF). The local biosphere-radiation mechanism proposed by Charney cannot explain the climatology of such very dry centers. Neither can the monsoon-desert mechanism proposed by Rodwell and Hoskins do for the strongest descent center is much more northward than the driest center over Sahara in JJA. From the viewpoint of local meridional circulation, the dryness climatology of Sahara and Northwest China deserts is investigated and compared. It is shown that in DJF, descent of local meridional circulation dominates the two deserts and very dry climate is unavoidable although the relative wet season is weak over the northern part of Sahara due to Mediterranean climate. While in JJA, there is ascent over the two deserts especially over Northwest China. Such ascent can explain the rainy season in south part of Sahara and Northwest China deserts. However, it is the local meridional circulation that takes strong and dry northerly from higher latitudes. The northerly either takes little moisture to the centers or prevents deep and strong convection over the centers. Such local meridional circulation leads to the dry climatology over the two deserts.

关键词： deserts local meridional circulation

Geothermal Energy Utilization in Jordanian deserts

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International Journal of Geosciences 2019年第10期10卷 906-918页

作者： Sanaa Al-Zyoud Department of Applied Earth and Environmental Sciences Institute of Earth and Environmental Sciences Al Al-Bayt University Al Mafraq Jordan

Jordan is blessed with shallow geothermal resources in NE and SE deserts. Jordanian deserts compose more than 70% of the country area. Furthermore, it’s the second vital area in fauna and flora variation after Jordan valley. Geothermal gradient in this area shows high promising future potential. New renewable energy systems installation in Jordan will have a positive environmental and economic contribution to the national bill. Currently, limited geothermal utilizations were evaluated in the Jordanian deserts. Thermal waters in the deserts were used for irrigation only. Six different applications for direct and indirect geothermal applications in Jordanian deserts were suggested and evaluated. Ground source heat pumps for heating and cooling purposes and crops drying were expected to be the most appropriate applications of geothermal energy in the deserts. Geothermal utilizations were investigated regarding their probable impact on local and national economic scale. Therefore, an integrated plan for geothermal applications in Jordan is becoming very essential in the future. It has been found that geothermal energy in Jordanian deserts could be utilized for different applications. Despite of the potential political, technical and financial barriers, exploiting new geothermal utilization in the deserts will contribute to solving socio-economic and environmental problems challenging poor deserts areas.

关键词： Geothermal Shallow Systems Direct and Indirect Utilization deserts Jordan

Turning deserts to Oases

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Beijing Review 2019年第36期62卷 2-2页

Miracles are occurring in northwest China where stretches of deserts are turning green with thriving trees and luxurious grass. Decades of efforts have resulted in triumph in the battle against desertification and China has not only achieved the UN sustainable development goal of zero net land degradation by 2030 well ahead of schedule, but also reversed the trend of desertification and sandification.

关键词： northwest deserts sandification

Spatial and temporal variability of soil water in drylands:plant water potential as a diagnostic tool

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Forestry Studies in China 2008年第2期10卷 74-80页

作者： Maik VESTE Markus STAUDINGER Manfred KüPPERS Research Center for Landscape Development and Mining Landscapes Brandenburg University of TechnologyCottbus D-03046Germany Institute of Botany and Botanical GardenUniversity of HohenheimStuttgart D-70599Germany AVL-ARGE Vegetation Ecology and Landscape Planing GmbH Wien A-1060Austria Institute of Botany and Botanical Garden University of HohenheimStuttgart D-70599Germany

Arid and semi-arid regions are characterized by low rainfall and high potential evaporative demand. Here, water is the major limiting factor for plant growth and productivity. Soil and surface hydrology properties （e.g. field capacity, infikration rates） effectively control the water re-distribution in the ecosystem, a fact that is aggravated in arid environments. Information of the spatial and temporal accessibility of soil water in desert ecosystems is limited. The purpose of the studies is the application of plant water potential to estimate the spatial and temporal variations of soil water availability in different arid ecosystems of the Negev （Israel） and southern Morocco. As model plants the evergreen shrubs Retama raetam, Thymelaea hirsuta and trees （Acacia tortilis） were chosen. Seasonal and spatial variations of the pre-dawn water potential （ψpd） were examined as diagnostic tool to determine water availability on the landscape level. The seasonal differences in the pre-dawn water potential were less pronounced on the dune compared to the interdune. This showed a better water availability on the dune slope. Also in the investigated wadis systems spatial differences of the water potential could be detected and related to the vegetation pattern.

关键词： soil water pattern predawn potential deserts Nizzana Negev

THE PATTERN OF GENERAL ATMOSPHERIC CIRCULATION IN EASTERN ASIA BEFORE THE UPLIFT OF THE TIBETAN PLATEAU

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地学前缘 2000年第S1期7卷 399-400页

作者： Jiang Xinsheng, Pan Zhongxi, Fu Qingping (Chengdu Institute of Geology and Mineral Resources,Chinese Academy of Geological Sciences, Chengdu 610082 , China)

The global climatic change study is a hot point *** 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 *** 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 *** present years,the pattern of the general circulation of the atmosphere has attracted great concern from *** 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 *** 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 *** is true that before the Early Tertiary,not only organism, but also inorganism,i.e.,biogeography and lithogeography, show strong zonal *** can only indicate that zonal climate was evident at that *** 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 *** it would be much better if direct record of planetary wind system were *** winds are the main geological agent for a desert

关键词： Cretaceous deserts regularity of paleowind directions pat tern of paleowind belts uplift of the Tibet Plateau

Two response patterns to negative environmental changes:Cases from Populus and Metasequoia

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Global Geology 2023年第2期26卷 63-73页

作者： ZHANG Yi XIONG Zhifeng GUO Shuangxing College of Paleontology Shenyang Normal UniversityShenyang 110034China Key Laboratory for Evolution of Past Life in Northeast Asia Ministry of Natural ResourcesShenyang 110034China Nanjing Institute of Geology and Palaeontology Chinese Academy of SciencesNanjing 210008China

Traditionally,plant distribution is thought to be closely related to environmental *** recently,it is found that Populus,quite different from other plant taxa,adapted to negative environmental changes,and successfully migrated to different climate zones from its origin places of warm temperate ***,Metasequoia is gradually tending to extinction from the Miocene to *** on above contrary cases,two response patterns of plant to negative environmental changes are *** is active adaptation represented by Populus,the other is passive adaptation represented by *** plants of passive strategy characterized for desert prevention might be easily replaced by those of active strategy characterized for desert *** growing plants,such as Populus with characteristics of drought and salt tolerance,wind and sand resistance,are selected in Tarim Basin in southern Xinjiang,China,as a good example of desert utilization in the construction of new highways and towns,not only serve as farmland shelterbelt in sandy *** addition,Populus with high-altitude and cold adaptation has also been selected as an ideal tree planted in ***,the idea of using Populus as one of the preferred pioneer trees to colonize Mars is proposed.

关键词： active adaptation passive adaptation Populus Metasequoia deserts Mars

Dasht-e Lut in Iran, the Most Complete Collection of Beautiful Geomorphological Phenomena of Desert

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Open Journal of Geology 2014年第6期4卷 249-261页

作者： Abdollah Yazdi Mohammad Hashem Emami Seyed Mohsen Shafiee Department of Geology Islamshahr Branch Islamic Azad University Islamshahr Iran Department of Geology Kahnooj Branch Islamic Azad University Kerman Iran

Given special tectonic and climatic conditions, Iran has the most diverse land-forms and beautiful geological phenomena, which could attract many scientific, adventurous tourists and geological researchers. The present study aims at studying and introducing wonderful geomorphological attractions and numerous geotourism potentials of very hot paradise of the earth, e.g. Dasht-e Lut of Iran, a desert which contains a collection of exclusive desert relieves and geological and geomorphological records of the world. Such unique perspectives as the biggest Nebkhas of the world, the largest Yardangs or Kaluts of the world, the hottest point of the earth, as well as rare species of desert structures such as salt marshes and salt polygons, Gandom Beryan Hill, massive sand dunes, Barchans, clay zones in pretty shapes, saline river , etc., present a vast and diverse extension of geographical beauties and phenomena of the desert. Using library studies, interpretation of satellite images and field studies, this study has been conducted. The results of the studies show that Lut Desert has considerable capability for carrying out complementary studies as well as effect on economic development process in national and international levels. In addition, geotourism development obstacles in Lut Desert are identified, and such solutions as development of ways for access to attractions, erection of geotourism development centers, advertisement and introduction of the desert's attractions, dispatch of guides with tourists, promotion of the region security, extension of accommodations and… for better use of the potentials of the desert, are provided. Furthermore, towards developing the region geotourism, some other fun and exciting activities such as sand skiing, racings and desert rallies, endurance cycling, sun bath, star observation, camel riding and so on, are suggested. Obviously, having various desert attractions and multiple geotourism potentials, Dasht-e Lut has the capability of b

关键词： Geomorphology Geotourism Dasht-e Lut deserts Kalut Iran

Elemental tracers for Chinese source dust

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Science China Earth Sciences 1996年第5期39卷 512-521页

作者：张小曳张光宇朱光华张德二安芷生陈拓黄湘萍 Xi'an Laboratory of Loess & Quaternary Geology. Chinese Academy of Seienees Xi'an 710054. China Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China Laboratory of Chmate Research National Meteorological Bureau Beijing 100081 China

The mass-particle size distributions of 10 dust-carrying elements in aerosol particles were determined tor 12 sites in desert regions of northern China. The desert dust is proved to he of origin of eolian loess deposited on the Loess Plateau. Their transport to the loess was mainly attributable to the non-dust storm processes under the interglacial climate condition. The impact ot" dust storm on the accumulation of the loess increased in the glacial stage. On the basis of the signatures of 4 dust elements (Al. Fe, Mg and Sc). Chinese dust is believed to have 3 major desert sources (northwestern deserts, northern high dust deserts and northern low dust deserts). With a chemical element balance model, an elemental tracer system is established to proportion the export of China-source dust.

关键词： Chinese deserts mineral dust atmospheric trace elements elemental tracer.