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Science China Earth Sciences 2004年第8期47卷 727-738页

作者： JIANG Xinsheng PAN Zhongxi XIE Yuan LI Minghui Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Chengdu Institute of Geology and Mineral Resources CGSChengdu 610082China Chengdu Institute of Geology and Mineral ResourcesCGSChengdu 610082China Chengdu Institute of Geology and Mineral ResourcesCGSChengdu 610082China Chengdu Institute of Geology and Mineral ResourcesCGSChengdu 610082China

Climatic state under greenhouse effect is a currently hot point. Whether greenhouse climate in geological history, especially in Cretaceous, was equable or not has aroused extensive discussion. By analysis on depositional cyclcity, wind direction change and hydrologic cycle variation of Cretaceous desert in the Ordos Basin of China, the unequability of Cretaceous cli-mate is dealt. It is shown that Cretaceous climate was extremely cyclic, not only having long and mid term but also having strong seasonal even instantaneous changes. Therefore, it is sug-gested that Cretaceous climate was not equable.

关键词： Ordos Basin of China,Cretaceous desert cycle,wind direction change,hydrologic cycle variation,Cretaceous climatic unequability.

Vegetation and climate history of Anggertu Lake in the Tengger desert over the last millennium

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Journal of Oceanology and Limnology 2018年第6期36卷 2166-2180页

作者： DUAN Futao AN Chengbang ZHAO Yongtao WANG Wei CAO Zhihong ZHOU Aifeng College of Earth Environmental Sciences MOE Key Laboratory of Western China's Environmental SystemsLanzhou University

Reconstructing climate change of the last millennium is important to understand the current relationship between human-social activities and natural environmental changes. Pollen assemblages, losson-ignition(LOIo rg at 550°C), and grain size data collected from sediment core AGE15 A from the center of Anggertu lake(eastern Tengger desert, Inner Mongolia) were used to reconstruct the regional vegetation and climate history of the last millennium. desert or steppe desert, dominated by A rtemisia and Amaranthaceae, expanded around this region during the period of 988–1437 AD indicating a generally dry climate condition with two short humid periods(1003–1082 AD and 1388–1437 AD). These two wet periods were characterized by relatively high vegetation cover and bioproductivity, as reflected by high pollen concentrations and LOIo rg values. Increases in steppe and meadow vegetation communities(Poaceae, Cyperaceae) and vegetation cover during 1437–2015 AD suggest a wetting trend, which was also deduced from a gradual trend towards fine grains and higher lake biological productivity as reflected by LOIo rg values. An unstable lacustrine environment was identified via frequent fluctuations in pollen concentration and grain size after 1842 AD. This study also recorded a relatively dry Medieval Warm Period(MWP, 1082–1388 AD) and a wet Little Ice Age(LIA, 1437–1842 AD). Increased Amaranthaceae and high abundance of Poaceae may be related to overgrazing and agricultural activities that took place during those time periods. The evolution of vegetation in the lake region was influenced by climate change and human activities. These results could provide more fundamental support for studies of the environmental evolution of the Tengger desert.

关键词： Anggertu Lake Tengger desert lacustrine record vegetation climate changes the last millennium

Bulk transfer coefficients of the atmospheric momentum and sensible heat over desert and Gobi in arid climate region of Northwest China

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Science China Earth Sciences 2002年第5期45卷 468-480页

作者：张强卫国安黄荣辉曹晓彦 Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

By utilizing the data of the intensive observation period (May-June, 2000) of Dunhuang land-surface process field experiment that belongs to 'Land-atmosphere Interactive Field Experiment over Arid Region of Northwest China', the bulk momentum transfer coefficient Cd and bulk sensible heat transfer coefficient Ch between surface and atmosphere over desert and Gobi in the arid region are determined according to three different methods. The result shows that, though these bulk transfer coefficients are different, they are in the same order. Especially, the means of Cd and Ch are close. Moreover, through analyzing the wind direction, the interference of the building near the observational station with the data is eliminated. From this, the relation between the bulk transfer coefficients and the bulk Richardson number and the range of the typical values of the bulk transfer coefficients over desert and Gobi in the typical arid region are obtained.

关键词： desert and Gobi, bulk transfer coefficient, bulk Richardson number, interference of building.

New Phenotypes of Limnocythere inopinata from Lakes in Badain Jaran desert,Northern China

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1411-1412页

作者： JIANG Gaolei ZHAI Dayou ZHAO Hua SHEN Jianmei NIE Zhenlong LIU Linjing MAO Xin WANG Zhe Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Key Laboratory of Quaternary Chronology and Environment Evolution China Geological SurveyShijiazhuang 050061China Yunnan Key Laboratory for Palaeobiology Yunnan UniversityKunming 650091China

Objective Limnocythere inopinata(Baird,1843)is an ostracod widely distributed in recent non-marine waters and in Quaternary sediments,where it comprises various phenotypes(Yin et al.,1999;Zhang et al.,2015).Based on the nodation patterns,five phenotypes were described in previous publications,namely,the unnoded,the phenotype with one node in the postero-ventral part of the valve,one with two nodes in the antero-ventral and postero-ventral parts of the valve,another with three nodes in the antero-ventral,postero-ventral and postero-dorsal parts of the valve.

关键词： desert Quaternary waters

Inversion of the asymmetry factor for desert areas of China

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Science China Earth Sciences 2010年第4期53卷 561-567页

作者： WU YunZhao LU HuaYu LIU Qiang School of Geographic and Oceanographic Sciences Nanjing UniversityNanjing 210093China Institute of Remote Sensing Applications Chinese Academy of SciencesBeijing 100101China

deserts,which have high surface albedo and wide area,are important components of the earth *** is very important for the research of surface radiation and energy balance to understand the anisotropic scattering of desert *** emergence and development of multi-angle remote sensing made possible the inversion of the anisotropic scattering of desert areas at the regional or global ***,this paper explored the accuracy of the inversion of asymmetry factor using the Hapke model and the simulated single-and multi-phase MISR *** on the results,the asymmetry factor of representative surface of desert areas in northwestern China was *** values of the asymmetry factor retrieved from MISR data were compared with the values retrieved from the laboratory *** results showed that the single-phase MISR data could be used for the inversion of asymmetry parameter of desert *** sign of the asymmetry parameter for the laboratory measurements was positive,which suggests that the surface of laboratory samples is forward *** sign of the asymmetry parameter for MISR data was negative;that is,it is *** values of the asymmetry parameters retrieved from MISR data were related to the character of the land *** Loulan,where the surface was smoother than other sites,retrieved values exhibited the largest negative values of asymmetry factor,suggesting the strongest *** sand dune area of the Kumtag desert,which has the greatest roughness,had only slightly negative asymmetry factor *** findings indicated that at the sensor scale,a rough surface(e.g.,dunes) does not necessarily mean more backscattering than a smooth *** finding has significant implications for empirical methods(e.g.,using the normalized index of backward-scattered radiance minus forward-scattered radiance as an indicator of surface roughness),which should be used carefully for analyzing surface roughness from the remote

关键词： MISR Hapke model asymmetry parameter inversion Kumtag desert multi-angle remote sensing

Patterns of shrub species richness and abundance in relation to environmental factors on the Alxa Plateau:Prerequisites for conserving shrub diversity in extreme arid desert regions

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Science China Earth Sciences 2009年第5期52卷 669-680页

作者： XinRong Li HuiJuan Tan MingZhu He XinPing Wang XiaoJun Li Shapotou desert Research and Experiment Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Shrub species are considered the dominant plants in arid desert ecosystems, unlike in semiarid steppe zones or in grassland ecosystems. On the Alxa Plateau, northern China, sparse vegetation with cover ranging from 15... 详细信息

关键词： biodiversity conservation shrub species richness abundance Alxa Plateau desert ecosystems

Palaeomonsoon vicissitudes in eastern desert region of China since last interglacial period

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Science China Earth Sciences 1998年第2期41卷 215-224页

作者：董光荣王贵勇李孝泽陈惠忠金炯 1. Xi'an Open Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences 710054 Xi'an China 2. Institute of desert Research Chinese Academy of Sciences 730000 Lanzhou China

Based on the geological records, the palaeomonsoon in eastern desert region of China is divided into three major evolution stages, i.e. summer monsoon prevailing stage of last interglacial period (130-70kaB.P.), winter monsoon prevailing stage of last glacial period (70-10 kaB.P.), and unstable summer monsoon prevailing stage of postglacial period (10 kaB.P. to present) and further divided into several substages. The conversion between summer monsoon and winter monsoon in the region is dominated by the sudden change process. The north limit of summer monsoon in the region retreated to the north limit of sandy loess zone of the Loess Plateau in the last glacial period from the Mazong Mts.-Ulan Bator of last interglacial period, then it entered Shandan-Yabrai region in the optimum period of the Holocene, and finally it retreated to the present extended line from north piedmont of the Yinshan Mts to Hulun Buir. This shows that the summer monsoon caused by East Asian monsoon circulation tends to be weakened fluctuationally. However, the factors affecting the monsoon vicissitudes are complex, so special attention should be paid to the study of the short-period climatic fluctuations of the Holocene.

关键词： last interglacial period eastern desert region monsoon vicissitude.

Remote sensing based shrub above-ground biomass and carbon storage mapping in Mu Us desert,China

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Science China(Technological Sciences) 2010年第S1期53卷 176-183页

作者： XU Min 1,2,CAO ChunXiang 1,TONG QingXi 1,LI ZengYuan 3,ZHANG Hao 1,HE QiSheng 1,2,GAO MengXu 1,2,ZHAO Jian 1,2,ZHENG Sheng 1,2,CHEN Wei 1,2 & ZHENG LanFen 1 1State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University,Beijing 100101,China 2 Graduate School of the Chinese Academy of Sciences,Beijing 100049,China 3 Research Institute of Forest Resources and Information Techniques,Chinese Academy of Forestry,Beijing 10009,China 1. State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China 2. Graduate School of the Chinese Academy of Sciences Beijing 100049 China 3. Research Institute of Forest Resources and Information Techniques Chinese Academy of Forestry Beijing 10009 China

The estimation of above-ground biomass(AGB) and carbon storage is very important for arid and semi-arid ***-1A/B satellite data combined with field measurement data was used for the estimation of shrub AGB and carbon storage in the Mu Us desert,*** correlations of shrub AGB and spectral reflectance of four bands as well as their combined vegetation indexes were respectively analyzed and stepwise regression analysis was employed to establish AGB prediction *** prediction equation based on ratio vegetation index(RVI)was proved to be more suitable for shrub AGB estimation in the Mu Us desert than *** AGB and carbon storage were mapped using the RVI based prediction model in *** statistics showed the western Mu Us desert has relatively high AGB and carbon storage,and that the gross shrub carton storage in Mu Us desert reaches 16 799 200 t,which has greatly contributed to the carbon fixation in northern China.

关键词： above-ground biomass carbon storage Mu Us desert HJ-1A/B remote sensing

Characteristics and source of black carbon aerosol over Taklimakan desert

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Science China Chemistry 2010年第5期53卷 1201-1208页

作者： FU S.Joshua Department of Civil and Environmental Engineering The University of Tennessee

Black carbon(BC) and PM10 in the center of the Taklimakan desert were online monitored in the whole year of *** addi-tion,TSP samples were also synchronously daily collected by medium-volume samplers with Whatman41 filters in the spring of *** in the dust aerosol was up to 1.14%of the total mass of PM10.A remarkable seasonal variation of BC in the aerosol was observed in the order of winter>spring>autumn>*** peak value of BC appeared at midnight while the lowest one in the evening each day,which was just the reverse of that in the urban *** contribution of BC to the total mass of PM10 on non-dust storm days was～11 times of that in dust *** back trajectory and principal component analysis,it was found that BC in the dust aerosol over Taklimakan desert might be attributed to the emission from the anthropogenic activities,including domestic heating,cooking,combustion of oil and natural gas,and the medium-range transport from those oases located in the margins of the *** total BC aerosol from the Taklimakan desert to be transported to the eastward downstream was estimated to be 6.3×104 ton yr-1.

关键词： black carbon aerosol the Taklimakan desert long-range transport

Satellite image analysis and study of Taklimakan desert rain trails

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Science China Chemistry 1995年第9期38卷 1146-1153页

作者：徐希慧 Xinjiang Meteorological Bureau Urumqi 830002China

The Taklimakan desert nephsystem and rain trails after heavy precipitation have been moni-tored continuously for 3 years by using TIROS-N/NOAA meteorological satellite of the United *** facts and its statistical characteristics of the desert rain trails are mainly *** weathersystems which form the deset rain trails are *** significance and some other problems of desertrain trails are also discussed.

关键词： satellite image monitoring desert heavy rainfall desert rain trails drought.