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Chinese Science Bulletin 2002年第1期47卷 76-78页

作者： DENG Tao, DONG Junshe & WANG YangInstitute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China Laboratory of Palaeobiology and Stratigraphy, Chinese Academy of Sciences, Nanjing 210008, China Department of Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing China Laboratory of Palaeobiology and Stratigraphy Chinese Academy of Sciences Nanjing China Department of Geological Sciences Florida State University Tallahassee USA

Stable carbon isotopes of C3 and C4 plants have completely distinct δ13C values respectively. Carbonate in tooth enamel of herbivorous mammals is significantly and regularly enriched in 13C compared to source carbon. As a result, we can reconstruct distributions of C3 and C4 plants in geological history based on carbon isotopes of mammalian tooth enamel. Carbon isotopes of 70 mammalian tooth enamel samples from 11 quaternary.localities in northern China are analyzed. This analysis indicates that C3 plants were dominant in the terrestrial ecosystem of northern China during the quaternary. which is completely different from Pakistan with relatively close latitudes where C4 plants were absolutely dominant. The great difference was caused by the uplift of the Tibetan Plateau. A simulation implied that a marked temperature decrease would happen in the north side of the Tibetan Plateau, but a temperature increase in the south side. The warming condition caused the transition from C3 to C4 plants in Pakistan

关键词： enamel carbon isotope northern China terrestrial ecosystem quaternary.

Demographic history of the Tibetan antelope Pantholops hodgsoni(chiru)

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Journal of Systematics and Evolution 2010年第6期48卷 490-496页

作者： 1,2,3Yu-Rong DU 1Song-Chang GUO 4Zhao-Feng WANG 1Hai-Xing CI 1Zhen-Yuan CAI 4Qian ZHANG 1Jian-Ping SU 4Jian-Quan LIU 1(Key Laboratory of Evolution and Adaptation of Plateau Biota,Northwest Institute of Plateau Biology,Chinese Academy of Sciences,Xining 810001,China) 2(Graduate University of the Chinese Academy of Sciences,Beijing 100049,China) 3(School of Life and Geography Science,Qinghai Normal University,Xining 810008,China) 4(Key Laboratory of Arid and Grassland Ecology,School of Life Science,Lanzhou University,Lanzhou 730000,China) (Key Laboratory of Evolution and Adaptation of Plateau Biota Northwest Institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China) (Graduate University of the Chinese Academy of Sciences Beijing 100049 China) (School of Life and Geography Science Qinghai Normal University Xining 810008 China) (Key Laboratory of Arid and Grassland Ecology School of Life Science Lanzhou University Lanzhou 730000 China)

The Tibetan antelope(chiru,Pantholops hodgsoni),a heavily poached species and symbol of the QinghaiTibetan Plateau(QTP),is noted worldwide for its special calving *** species originated in the early quaternary.and it is interesting to know how the following climatic oscillations affected its demographic dynamics in the climate-sensitive *** this study,we analyzed the mitochondrial D-loop region from 312 individuals sampled in all of the six major *** found high rates of gene flow and little genetic differentiation between populations,suggesting that the calving migration may have homogenized the genetic pool of this *** mismatch distribution analyses and coalescent simulations suggested that this species experienced a demographic expansion approximately 600-200 Kyr following the retreat of the large glaciers developed in the QTP at 800-600 Kyr,rather than at the end of the last glacial age,as previously suggested,based on a limited sample *** addition,we found evidence of a chiru population decrease probably related to the human settings at the QTP during the middle Holocene.

关键词： chiru calving migration demographic expansion mitochondrial D-loop quaternary.

Distributions of fatty acids in a stalagmite related to paleoclimate change at Qingjiang in Hubei,southern China

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Science China Earth Sciences 2005年第9期48卷 1463-1469页

作者： XIE Shucheng1,HUANG Junhua1,WANG Hongmei2,YI Yi1,HU Chaoyong1, CAI Yanjun3 & CHENG Hai4 1. Faculty of Earth Science,China University of Geosciences,Wuhan 430074,China 2. School of Environmental Studies,China University of Geosciences,Wuhan 430074,China 3. SKLLQG,Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,China 4. Department of Geology and Geophysics,University of Minnesota,MN55455,USA Faculty of Earth Science China University of Geosciences Wuhan China School of Environmental Studies China University of Geosciences Wuhan China SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an China Department of Geology and Geophysics University of Minnesota USA

Fatty acids extracted from a subtropical stalagmite at Qingjiang in Southern China’s Hubei Province were analysed using gas chromatography-mass spectrometry. These n-alkanoic acids range from C14 to C26 in carbon number, maximizing at C16, with a second dominance at C22. In contrast to the stalagmite analysed, the overlying soils are characterized by the dominance of heavy-molecular-weight homologues (>C20). The n-fatty acids in the stalagmite were proposed to be contributed by both the soil ecosystems and the microbes harboring in the percolating water and the cave. The ratios of unsaturated to saturated n-fatty acids (C16:1i/C16:0, C18:1/C18:0) appear to show trends comparable with the oxygen isotope records of the stalagmite carbonate, with enhanced values associated with the cold episode such as Heinrich event 1. This paleoclimate-dependent record of the n-fatty acids might reflect microbial changes in physiology and activity in response to the temperature. This record shows somewhat difference from the previous paleoclimate signal extracted from n-alkanols and n-alkan-2-ones of the same stalagmite. The acid record fails to document the well-known Younger Dryas event which was effectively shown by the latter two biomarkers derived from soil ecosystems. This discrepancy might result from the changing biogeochemical impact on different lipid fractions as well as the varied organism populations in different ecosystems.

关键词： biomarker, ecosystem, microbe, speleothem, paleoclimate, quaternary.

The paleoclimatic events and cause in the Okinawa Trough during 50 kaBP

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Chinese Science Bulletin 2001年第2期46卷 153-157页

作者： S.Berne Y.Saito Key Laboratory of Marine Science and Numerical Modeling State Oceanic Administration (SOA) Qingdao China First Institute of Oceanography SOA Qingdao China Institute of Oceanology Chinese Academy of Sciences Qingdao China Taiwan University Taibei China French Oceanographic Institute IFREMER Plouzane France Geological Survey of Japan Tsukuba Japan

Planktonic foraminiferal δ18O record for core DGKS9603 from the Okinawa Trough shows a series of climatic fluctuations and sudden cooling events in short time scale during 50 kaBP, which appear to correlate closely tothe Younger Dryas and Heinrich events H1-5 recorded in Chinese loess, the South China Sea, the North Atlantic cores and the Greenland ice cores. Three polarity reversal events, correlating to Gothenburg, Mungo and Laschamp events, approximately correspond to Heinrich events H1, H3 and H5 respectively, which could be a cause of global climate changes. The δ18O curve of the Okinawa Trough is well associated with the grain size record of the Lijiayuan loess profile in northwestern China and is somewhat different from the climate fluctuations documented in the Greenland ice cores. These correlation results indicate that regional factors play an important role in controlling the climate changes in the East Asia, and the East Asian Monsoon could be the prominent regional controlling factor.

关键词： Okinawa Trough sudden paleoclimatic change events polarity reversal events Late quaternary.

Evolution of drainage systems and its developing trend in connection with tectonic uplift of Eastern Kunlun Mt.

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Chinese Science Bulletin 2000年第20期45卷 1904-1908页

作者： LI Chang’an YIN Hongfu YU Qingwen Faculty of Earth Sciences China University of GeoscienceWuhan 430074China China Geological Survey Bureau Beijing 100812China

The Eastern Kunlun Mt. had been subjected to uplift together with the Qinghai-Xizang (Tibet) Plateau before the Early Pleistocene, and yet the Mt. did not protrude out of the Plateau surface. During that period lakes spread all over the studied region, with the drainage systems being all short rivers flowing into the lakes. At the end of the Early Pleistocene, intensive tectonic uplift led to the rising of the Eastern Kunlun Mt. and made the Mt. protrude onto the Plateau surface. As a result, a fault depression valley formed extending nearly from west to east along the fault belt of the Southern Kunlun Mt. Lakes in this region died out, surface runoffs joined into the valley of the Southern Kunlun Mt. resulting in a large river streaming nearly from west to east. Around 150 kaBP, because of the strong differential movement, rivers, such as the Jialu River and the Golmud River, retrogressively eroded seriously, cutting through the Burhan Budai Mt. Then they pirated the large river and divided it into

关键词： Eastern Kunlun Mt. drainage systems tectonic uplift retrogressive erosion quaternary.

Stepwise advance of the Mu Us Desert since late Pliocene:Evidence from a red clay-loess record

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Chinese Science Bulletin 1999年第13期44卷 1211-1214页

作者： Zhongli Ding Jimin Sun Dongsheng Liu Institute of Geology Chinese Academy of Sciences Beijing China

Analyses of paleomagnetic polarity reversals, magnetic susceptibility and grain size on the red clay-loess sequence, about 280 m thick, at Jingbian show that this sequence contains most of the stratigraphic units recorded in the standard red clay-loess sections of the Loess Plateau over the past 3.5 Ma. Using sand particle percentage ( > 63 μm%) of the eolian sequence as a proxy indicator of desert extent and aridity in the dust source regions, it is found that during the past 3.5 Ma, there are three important climatic events indicating the advance of the Mu Us Desert. The events occurred at about 2.6, 1.1 and 0.6 MaBP, respectively. The stepwise advance of the Mu Us Desert may be linked closely to increase in global ice volume and uplift of the Tibetan Plateau in the late Cenozoic.

关键词： loess desert quaternary.

Expansion and contraction of Chinese deserts during the quaternary

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Science China Earth Sciences 2002年第Z1期45卷 91-101页

作者：刘东生孙继敏 Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Episodic dune formations during the quaternary.are found in many deserts of *** causes of desert expansions on different time scales are not the same. Desert extension atabout 1.1 and 0.9 Ma ago were the response to the active tectonic movements, whereas the de-sert evolutions on the ten-thousand years time scale were the response to the orbital scale climaticchanges. Spatial scale studies on desert evolution indicate that desert margins shifted greatly dur-ing the last glacial maximum (LGM) and the Holocene optimum, its changing from 125°E of theLGM to 105°E of the climatic optimum. Historical desertification in the semiarid China is not a re-sponse to climate drought but largely associated with the human impacts (mainly over-cultivation)since about 2300 years ago, which leads to the reworking of the underlying LGM sands.

关键词： expansion, contraction, desert, quaternary.

Paleosols from North Part of Barlad City （Romania）

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Journal of Earth Science and Engineering 2012年第2期2卷 71-76页

作者： Daniel Bejan Bogdan Gabriel Ratoi Mihai Branzila Department of Geology Faculty of Geography and Geology Alexandru loan Cuza University of lasi Iasi 700505 Romania

The loess deposits comprise several paleosol layers reflecting alternation of drier and wetter climate during quaternary. Such a situation occurs in north of Barlad, on The Sohodau＇s Hill. Morphological study of the quarry paleosols from north of Barlad was accomplished based on field observations and macroscopic physic-chemical results. Three levels of paleosols with variable thickness were determined. These three fossils layers are interbedded by four loess deposits. The physical-chimical data provide important information for the paleosol genesis and depositional/climatic environments. The carbon content and C/N ratio indicate the strength of pedogenesis in the Pleistocene and trends of biomass accumulation.

关键词： Paleosols loess deposits pedogenesis quaternary.

Intraspecific phylogeography of Carchesium polypinum (Peritrichia, Ciliophora) from China, inferred from 18S-ITS1-5.8S ribosomal DNA

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Science China(Life Sciences) 2004年第1期47卷 11-17页

作者： MIAO Wei, YU Yuhe, SHEN Yunfen & ZHANG XiyuanDonghu Experimental Station of Lake Ecosystems, Chinese Academy of Sciences, Wuhan 430072, China Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China College of Life Sciences, Wuhan University, Wuhan 430072, China Donghu Experimental Station of Lake Ecosystems Chinese Academy of Sciences Wuhan 430072 China Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China College of Life Sciences Wuhan University Wuhan 430072 China

Based on the variation of site 34, 46, 241, 305 and 322 in the 18S-ITS1 rDNA sequence, 19 Carchesium polypinum populations collected from eight provinces of China were separated into northern and southern population along the delineation between the Yangtze River and the Pearl River. This geographic distribution pattern of Carchesium polypinum maybe results from two factors: the vicariance resulting from the formation of the delineation between the Pearl River and the Yangtze River accompanied with the uplift of Qinghai-Xizang Plateau, and the different dispersal paths of C. polypinum affected by the climate.

关键词： Carchesium polypinum, phylogeography, 18S-ITS1 rDNA sequence, population, vicariance, dispersal, quaternary.

The occurrence of a grassy vegetation over the Chinese Loess Plateau since the last interglacier:the molecular fossil record

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Science China Earth Sciences 2002年第1期45卷 53-62页

作者：谢树成陈发虎王志远安成邦王红梅 Faculty of Earth Science China University of Geosciences Wuhan 430074 China Department of Geography Lanzhou University Lanzhou 730000 China

A series of allochthonous and autochthonous molecular fossils were identified from the Holocene paleosol (S0), Malan Loess (L1) and the top Lishi Loess (S1) in Jiuzhoutai loess profile in Lanzhou through the GC/MS analysis. The allochthonous molecules were transported into the Plateau by the loess grains whilst the autochthonous molecules were related to the input of the local paleo-vegetation and could be used to reconstruct the paleo-vegetation. The distribution of the autochthonous n-alkanes was discriminated from the overlapping allochthonous homologues characterized by the CPI value of unity. The dominance of autochthonous C31 n-alkane implicates the occurrence of a grassy vegetation over the Loess Plateau since the last interglacier. The warmest period of the Holocene, though dominated by grass, was additionally characterized by the relatively increased abundance of C27 n-alkane indicative of woody plants. The desert plants might occur during the last glacier. The molecular fossil record is not con

关键词： molecular fossil n-alkane paleo-vegetation loess paleosol Lanzhou quaternary.