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Magnetostratigraphy of Late Cenozoic fossil mammals in the northeastern margin of the Tibetan Plateau

Science Bulletin 2003年第2期48卷 188-193页

作者： SONG Chunhui1,2.FANG xiaomin 1,2.GAO Junping1, NIE Junsheng1,YAN Maodu1,3,XU xianhai1 & SUN Dong1 1. MOE National laboratory of Western china抯 {2.al Systems & College of Resource and {2.,Lanzhou University,Lanzhou 730000,china 2. state key laboratory of loess and quaternary geology ,institute of earth {2.,chinese academy of sciences,xi抋n {12., china 3. Department of Geological sciences,University of Michigan,AnnArbor,MI 48109,USA Univ Arizona Steward Observ Tucson AZ 85721 USA MOE National laboratory of Western china\'s {2.al Systems & College of Resource and {2. Lanzhou University Lanzhou 730000 China

A number of fossil mammals have been found in the very thick Cenozoic stratigraphy of the Guide Basin in the northeastern margin of the Tibetan *** of these are of great significance in mammal evolution and stratigraphic correla-tion on and around the Tibetan Plateau and North ***,the chronology of these mamals is poorly *** of the mammals will not only place precise age constraints on the mammals,but also provide much inlormation on the related stratigraphy that records the uplift process of the Tibetan *** paleomagnetism of the upper part of the Cenozoic stratigraphy at He'erjia and Lajigai north of Guide County has revealed magnetic chrons that can be correlated to Ganss and 3An *** the section spanning about 3.16.5 Ma and the *** and third layers of fossil mammals at about 5.2.,5.1 and 4.4 Ma,*** of the significant genus Gazella kueitensis and the chinese elephant Anancus sinensis are firstly constrained at about 5.2. MaBP and 4.4 Ma,*** mammalian evolution and the associated increase in coarse sediments and sedimentation rate may suggest that the northeastern Tibetan Plateau was uplifted rapidly at that time,and the eastern Tibetan Plateau with its neighboring regions was not high enough to stop mammal exchange between the northern and southern sides of the Tibetan Piateau.

关键词： Tibetan Plateau Guide Basin Late Cenozoic stratigra-phy fossil mammals paleomagnetism.

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The δ^(18)O variation of a stalagmite from Qixing Cave,Guizhou Province and indi-cated climate change during the Holocene

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chinese Science Bulletin 2001年第22期46卷 1904-1908页

作者： CAI Yanjun, ZHANG Meiliang, PENG Zicheng, LIN Yushi, AN Zhisheng, ZHANG Zhaofeng & CAO Yunningstate key {2. of loess and quaternary geology, institute of earth environment, chinese academy of sciences, xi’an 710054, china Karst Dynamics {2., Ministry of Land and Resources, Guilin 541003, china Department of earth and Space Science, University of Science & Technology of china, Hefei 2.002., china state key {2. of loess and quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Karst Dynamics laboratory Ministry of Land and Resources Guilin China Department of earth and Space Science University of Science & Technology of China Hefei China

A stalagmite from Qixing Cave, Guizhou Province was dated with the TIMS U-series method and its oxygen isotope composition was analyzed. On the basis of the ages and the variations of the δ18O of the stalagmite, the climate change of the last 7.7 ka has been reconstructed in this area: 7.7-5.8 ka, summer monsoon maximum period; 5.8-3.8 ka summer monsoon weakening period; 3.8-0.15 ka, weakened summer monsoon and high amplitude climate fluctuations period. We put forward that the increasing trend of δ18O of the stalagmite reflected not only the weakening of the summer monsoon, which was caused by the decreasing of solar radiation in the Northern Hemisphere, but also the possibly decreasing contribution of the southwest monsoon to the rainfall of this area. These results are consistent with the output of the numerical climate-model modeling. The high amplitude fluctuation of the δ18O may imply the quick shift of the contributions of different moisture sources to the precipitation in this area.

关键词： stalagmite Holocene southwest monsoon.

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Sun-coupled climate connection between eastern Asia and northern Atlantic

Sun-coupled climate connection between eastern Asia and nort...

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中国科学院地质与地球物理研究所2.04学术年会

作者： Ming Tan institute of geology and Geophysics,{2. academy of sciences,Beijing,china state key laboratory of loess and quaternary geology,institute of earth environment,{2. academy of sciences, xi’an.Shaanxi,china Juzhi Hou institute of geology and Geophysics,{2. academy of sciences,Beijing,china Tungsheng Liu institute of geology and Geophysics,{2. academy of sciences.Beijing,china state key laboratory of loess and quaternary geology.institute of earth environment.{2. academy of sciences. xi’an.Shaanxi.china

[1]Few of annually resolved Proxy temperature records are reported to coincide with centennial

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Early agricultural development and environmental effects in the Neolithic Longdong basin(eastern Gansu)

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chinese Science Bulletin 2011年第8期56卷 762-771页

作者： ZHOU xinYing LI xiaoQiang ZHAO KeLiang DODSON John SUN Nan YANG Qing state key {2. of loess and quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi'an 710075 China laboratory of Human Evolution and Archeological Science Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Graduate University of chinese academy of sciences Beifing 100049 China institute for environmental Research the Australian Nuclear Science and Technology Organization Sydney NSW 1001 Australia

Neolithic agricultural development and environmental effects in the Longdong area were reconstructed using a synthetic approach,investigating pollen,charcoal,and seed remains for two cultural layer sections and five flotation *** show that Neolithic agriculture in the Longdong area had a simple organization and was dominated by the production of common millet,especially in the early and middle Yangshao *** the late Yangshao age,Neolithic agriculture developed into a more complex structure,dominated by both common and foxtail millet and the cultivation of rice and *** production of foxtail millet gradually increased through the Neolithic period,reaching its highest point during the Qijia *** were first cultivated during the late Yangshao culture,approximately 5000 cal a *** production began no later than 4800 cal a BP,and continued to exist in the Qijia culture,approximately 4000 cal a *** production in Neolithic Longdong,specifically in the "Yuan" area of the loess plateau,developed as a shrub and grass dominated *** in the river valleys was partly covered with Picea,Tusga,and Quercus coniferous and broadleaf mixed *** activity during the Neolithic period caused an increase in farmland on the loess tableland and a decrease in the abundance of shrub and grassland in the Longdong *** farmlands were abandoned,vegetation recovered with Hippophae-,Rosaceae-,Ephedra-,and Leguminosae-dominated shrublands and Artemisia-dominated grasslands.

关键词：新石器时代农业发展陇东地区环境影响甘肃东部早期新石器时期盆地

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environmental archaeology of the Dachang region in the Daning Valley,the Three Gorges reservoir region of the Yangtze River,china

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chinese Science Bulletin 2008年第S1期53卷 140-152页

作者： ZHANG Yun 1 &ZHU Cheng 2.1 state key {2. of Vegetation and environmental Change,institute of Botany,chinese academy of sciences,Beijing 100093, china 2.School of Geographic and Oceanographic sciences,Nanjing University,Nanjing 2.0093,china state key {2. of Vegetation and environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China School of Geographic and Oceanographic sciences Nanjing University Nanjing 210093 China

environmental archaeology of archaeological sites on both sides of the Dachang section in the Daning River,the Three Gorges of the Yangtze River,shows that riverbed evolution has a great influence on the distribution of archaeological sites during the prehistorical and historical period,and it restricts human activity and the development of ancient *** investigation,dating data,paleocurrent analysis of 100 gravels on the riverbed and archaeological excavation reveal that the riverbed of the Dachang section developed in the Shuangyantang region during the early stage,after about 30 kaBP it shifted westward gradually and reached the present *** with the westward shift,the focus of ancient culture changed for several *** the Western Zhou Dynasty's period,the east riverbank of the Daning River was the main residential *** the Han Dynasty,along with the westward shift,the living space of ancient people was no longer confined to the east riverbank and the focus of culture moved *** the Zhangjiawan site became the main dwelling *** the late Han Dynasty, the villages were flooded and the ancients had to immigrate to a high *** of the Han and the Jin Dynasties outcropped on the flood plain of the east bank because their surface sediments were eroded by several flood events and the westward shift of the riverbed.

关键词： the Daning River environmental archaeology the Shuangyantang site the Zhangjiawan site tombs of the Han and the Jin Dynasties

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Effects of Land Use and Land Cover Change on Soil Properties in Mu Us Sand Land of Inner Mongolia, china

Effects of Land Use and Land Cover Change on Soil Properties...

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经济发展方式转变与自主创新——第十二届中国科学技术协会年会

作者： Zhao JIN (state key {2. of loess and Quatemary geology, institute of earth environment, chinese academy of Science. xi’an 710075, china) state key {2. of loess and Quatemary geology Institute of Earth Environment Chinese Academy of Science. Xi’an 710075 China

In arid and semiarid regions, cultivation and shrub invasion are two important factors to impact grassland. The land use and land cover change have been widely found to result in soil carbon and nitrogen loss. However, there are few studies to compare the effects of cultivation and shrub invasion on soil physical and chemical properties. In Mu Us sand land of Inner Mongolia, china, grassland cultivation and shrub invasion widely occur. We found that the grassland cultivation and shrub invasion significantly decreased the content of silt and clay and increased the content of sand. Moreover, the grassland cultivation and shrub invasion were found to lead to the soil carbon and nitrogen loss. In this study, grassland cultivation resulted in more sand accumulation and more soil carbon and nitrogen loss than shrub invasion of grassland. The results indicate that grassland cultivation was stronger than shrub invasion to accelerate soil desertification in arid and semiarid regions.

关键词： soil PSD SOC TN grassland cultivation shrub invasion

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The vegetation and climate change during Neocene and Early quaternary in Jiuxi Basin, china

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Science china earth {2. 2005年第5期 676-688页

作者： MA Yuzhen 1 , FANG xiaomin 1,2., LI Jijun 1 , WU Fuli 1 & ZHANG Jun 1 1. key laboratory of Western{2.’s environmental Systems and College of Resources and environment, Lanzhou University, Lanzhou 730000,{2. 2. state key laboratory of loess and quaternary geology, institute of earth environment, chinese academy of sciences, xi’an 710075, {2.

Sporopollen record in the Laojunmiao Section at Yumen in the Hexi Corridor foreland depression at the northern margin of the Tibetan Plateau revealed that during the period of 13.0―11.15 Ma the ecological environment of the Jiuxi Basin is characterized by steppe vegetation and a semi-moist climate. During 11.16―8.60 Ma prevailed forests of cypress and a still warmer, moister climate; steppe vegetation and dry climate began probably at about 8.6 Ma. Although aridification had been relaxed time and again during 8.40―6.93 Ma (forest-steppe, warm-semi-moist), 6.64―5.67 Ma (open-forest and steppe, warmer-semi-moist) and 5.42.4.96 Ma (steppe, semi-arid), the climate in the region became drier and drier in response to the fre- quent occurrence of aridity during 6.93―6.64 Ma (steppe, semi-arid), 5.67―5.42.Ma (de- sert-steppe, arid), 3.66―3.30 Ma (desert-steppe, arid) and 2.56―2.2. Ma (desert, arid). Perhaps the important findings of our study are the notable expansion of drought-enduring plants during 3.66―3.30 Ma and about 2.56 Ma and the replacement of vegetation by vast arid desert.

关键词： Tibetan Plateau Hexi Corridor sporopollen record ecological environment vegetation evolution aridific-ation.

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黄土高原450ka BP前后荒漠草原大迁移的初步研究

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土壤学报 2003年第5期40卷 651-655,T001页

作者：赵景波陕西师范大学地理系

根据野外调查和室内鉴定、分析 ,讨论了黄土高原 45 0kaBP前后的荒漠草原大迁移问题。资料表明 ,在地处黄土高原南缘的陕西长安少陵塬和西安白鹿塬 ,第 5层黄土形成初期有代表荒漠草原环境的石膏发育 ,指示当时黄土高原气候发生了显著... 详细信息

根据野外调查和室内鉴定、分析 ,讨论了黄土高原 45 0kaBP前后的荒漠草原大迁移问题。资料表明 ,在地处黄土高原南缘的陕西长安少陵塬和西安白鹿塬 ,第 5层黄土形成初期有代表荒漠草原环境的石膏发育 ,指示当时黄土高原气候发生了显著的干旱化与大幅度的荒漠草原南迁 ,气候带向南迁移了约 5个纬度 ,荒漠草原和更为荒凉的环境广布于黄土高原。石膏的发育还揭示 ,在 45 0kaBP前后黄土高原气候发生了性质的转变 ,由季风气候转变为非季风气候 ,当时该区已基本不受夏季风的影响 ,并处在非季风气候的环境下。

关键词：黄土高原荒漠草原大迁移非季风气候石膏干旱气候

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The new basic theory on quaternary environmental research

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Journal of Geographical sciences 2004年第2期14卷 242-250页

作者： ZHAO Jingbo 1, 2. 3 (1. Department of Geography, Shaanxi Normal University, xi’an 710062. china 2. Center for Historical environment and Socio-Economic Development in Northwest china, Shaanxi Normal University, xi’an 710062. china 3. state key laboratory of loess and quaternary, institute of earth environment, CAS,{12., china) Department of Geography Shaanxi Normal University Xi’an China Center for Historical environment and Socio-Economic Development in Northwest china Shaanxi Normal University Xi’an China state key {2. of loess and quaternary Institute of Earth Environment CAS Xi’an China

On the basis of extensive survey to the quaternary paleosols, soils and weathering layers in the vast northern china and the {2. Plateau, we found some unusually special phenomena of chemical components such as unsuccessive illuvium, twin illuviums, unusually thick illuvium and multi-illuviums etc. According to the analysis on the content of CaCO 3 and the data of penetrating experiment, a new theory of illuvial depth or removal depth of CaCO 3 in weathering and leaching belt was constructed, which indicates that the time of CaCO 3 removing to the illuvial depth is very short, and the effect of time factor on illuvial depth can be ignored. The theory can be taken as a credible foundation for studying many geological and geographical problems in weathering and leaching belt. When the illuvial depth of CaCO 3 is bigger than the thickness of developing belt of soil or paleosol, it can be determined that the paleosol has turned into weathering crust. When the illuvial depth of CaCO 3 is bigger than the thickness of paleosol, paleosol is leaching moderately acid soil. When two, three layers or unusually thick CaCO 3 illuviums exist in the same weathering section or at the bottom of the same paleosol, there were two or more periods forming paleosol and corresponding climatic stages at that time. On the basis of the equation of relationship between mean annual rainfall (y) and illuvial depth of CaCO 3 (x) (y = 305.5x + 168.5) determined in the paper, mean annual precipitation during the development of paleosol can be calculated.

关键词： new illuvial theory quaternary soils CaCO_3 remove illuvial types illuvial depth

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Aeolian Facies Belts in the Taklimakan Desert

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Acta Geologica Sinica(English Edition) 1995年第3期69卷 317-328页

作者： Li Baosheng, Dong Guangrong, Zhang Jiasheng, Li Sen,Jin Heling, Chen Huizhong, Wen xiangle, Wang Yao, Lanzhou Desert Research institute, chinese academy of sciences, Lamhou, Gansuand Zhu Yizhixi’an Open {2. of loess and quaternary geology, chinese academy of sciences, xi’an, Gansu Fei Zhenbi Lanzhou Desert Research institute Chinese Academy of Sciences Lanzhou Gansu China

At least at the beginning of the last glacial epoch, the facies belts of dune sand, sandy loam and loess formed by winds had existed in the Taklimakan desert and areas south of it. There were no appreciable changes in the NE and NW wind systems and their wind fqrces that deposited dune sand, sandy loam and loess in the global cold stage since the last glacial epoch (accordingly no marked shifts of the boundaries of these aeolian facies belts took place. In the global warm stage since then, the climate in the Taklimakan desert and areas south of it became warm and dry, resulting in ablation of substantial volumes of ice and snow in their surrounding mountains and thus forming alluvial and diluvial deposits in the region. The alluvial-diluvial actions, however, failed to change the general framework of aeolian facies belts.

关键词： Taklimakan desert sandy loam belt loess belt last glacial depositional environment

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