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Molecular fossil and paleovegetation records of paleosol S4 and adjacent loess layers in the Luochuan loess section, NW China

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Science China Earth Sciences 2008年第3期51卷 321-330页

作者： ZHANG HuCai YANG MingSheng ZHANG WenXiang LEI GuoLiang CHANG FengQin PU Yang FAN HongFang Key Laboratory of Western China’s Environmental Systems Ministry of EducationCollege of Earth and Environment SciencesLanzhou UniversityLanzhou 730000China State Key Laboratory of Lake and Environment Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China

Using gas chromatography-mass spectrometry (GC-MS) technique, a series of biomarkers were identi- fied, including n-alkanes, n-alkane-2-ones, isoprenoid etc. from the loess-paleosol samples collected from the S4 and adjacent L5, L4 of the Luochuan loess section, Northwestern China. Based on these data, especially n-alkanes and high-resolution magnetic susceptibility and grain size data, the pa- leoenvironment and paleovegetation history during S4 was reconstructed. The CPI (Carbon Predomi- nance Index) and correlation between n-alkanes and magnetic susceptibility and grain size data dem- onstrated that the molecular fossils in paleosol and loess layers can reflect the vegetation condition during the loess-paleosol formation, if the allochthonous organic inputs could be excluded reasonably. The ACL (average chain length) index is correlated well with paleomagnetic susceptibility and grain size variations, displaying their good synchrony with warm and humid climate. However, it relatively lagged behind the paleomagnetic susceptibility and the grain size variations when the climate began to deteriorate. During the formation period of paleosol, the n-alkanes was dominated by C31 homologue, indicating that the primary organic input originated from herbs. Our study also demonstrated that the herbs were more flourish than wood plants in Loess Plateau, especially in the Luochuan area during the warm and humid phase, and there was no typical forest vegetation developed in the studied period.

关键词： paleoenvironment Paleosol S4 Luochuan loess section biomarker paleovegetation

Comparison Study of paleovegetation and Paleoclimate in South and North Kunlun Mountains in Pliocene

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Science China Chemistry 1994年第12期37卷 1489-1498页

作者：黄赐璇 Institute of Geography Academia Sinica and the State Planning Commission of ChinaBeijing 100101PRC

According to the data of pollen analysis,the vegetation varied greatly between the southand the north of the Kurdun Mountains during the *** the south of the Kunlun Mountains,includ-ing their south flank,there was distribution of needle and broad-leaf mixed forest that contained tropical andsubtropical compositions,while to the north of the Kunlun Mountains,including their north flank,therewas distribution of temperate deciduous broad-leaf forest and *** both areas mentioned above,therewere scattered middle Asian arid plants of a lush growth in the late *** the Pliocene,the Pamir-Kunlun Ranges acted as the division line of the southern and northern types of ***,with the risingof these mountains,inciuding Pamir,Kunlun and Himalaya,this division line had been moving,until itreached the Xindukushi-Himalaya Mountains at present.

关键词： Pliocene Kunlun Mountains paleovegetation paleoclimate.

paleovegetation inferred from the carbon isotope composition of long-chain nalkanes in lacustrine sediments from the Song-nen Plain,northeast China

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Paleovegetation inferred from the carbon isotope composition...

Heterogeneous occurrence of evergreen broad-leaved forests in East Asia:Evidence from plant fossils

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Zhifu Wei Yongli Wang Baoxiang Wu Zixiang Wang Gen Wang Key Laboratory of Petroleum Resources Gansu Province/Key Laboratory of Petroleum Resources ResearchInstitute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences

Abundant n-alkanes were identified by GC/MS analysis in core sediments from Xianghai Lake and the Huola Basin,on the Song-nen Plain,northeast *** n-alkanes extracted from Xianghai Lake samples showed unimodal and bimodal *** main peaks of unimodal distribution were at n-C or n-C,and the mid-and long-chain nalkanes had odd-carbon-number predominance,suggesting they were derived mainly from terrestrial higher *** distributions of n-alkanes had maximum values centered at n-C and n-C in all *** short-chain n-alkanes with a maximum at n-C showed no odd–even predominance,however there was a strong odd-carbon-number predominance of long-chain n-alkanes,with a maximum at *** results suggest that organic matter in Xianghai Lake was derived from mixed sources,including bacteria,algae and terrestrial *** n-alkanesextracted from Huola Basin sediments were characterized by a unimodal distribution,with the maximum value at n-C,and the long-chain n-alkanes had an odd-carbon-number predominance,indicating that they were derived mainly from terrestrial higher *** addition,the compound-specific carbon isotope composition was determined for C27,C and Cn-alkanes in the core sediments,and the relative contributions of C and Cplants were estimated using a binary *** indicated that C plants were the dominant input during the late glacial and *** relative abundance of C and Cplants changed significantly through time,likely determined by cool versus warm climate conditions.

关键词： n-Alkanes d13C of long-chain nalkanes paleovegetation C3 and C4 plants Northeast China

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Plant Diversity 2025年第1期47卷 1-12页

作者： Jiagang Zhao Shufeng Li Jian Huang Wenna Ding Mengxiao Wu Tao Su Alexander Farnsworth Paul J.Valdes Linlin Chen Yaowu Xing Zhekun Zhou CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China University of Chinese Academy of Sciences Beijing 100049China Swiss Federal Institute for Forest Snow and Landscape Research WSL8903 BirmensdorfSwitzerland Senckenberg Natural History Collections Dresden Koonigsbrücker Landstraße 15901109 DresdenGermany State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation&Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China School of Geographical Sciences University of BristolBristol BS81SSUK State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Evergreen broad-leaved forests(EBLFs) are widely distributed in East Asia and play a vital role in ecosystem stability. The occurrence of these forests in East Asia has been a subject of debate across various disciplines. In this study, we explored the occurrence of East Asian EBLFs from a paleobotanical perspective. By collecting plant fossils from four regions in East Asia, we have established the evolutionary history of EBLFs. Through floral similarity analysis and paleoclimatic reconstruction, we have revealed a diverse spatio-temporal pattern for the occurrence of EBLFs in East Asia. The earliest occurrence of EBLFs in southern China can be traced back to the middle Eocene, followed by southwestern China during the late Eocene-early Oligocene. Subsequently, EBLFs emerged in Japan during the early Oligocene and eventually appeared in central-eastern China around the Miocene. Paleoclimate simulation results suggest that the precipitation of wettest quarter(PWet Q, mm) exceeding 600 mm is crucial for the occurrence of EBLFs. Furthermore, the heterogeneous occurrence of EBLFs in East Asia is closely associated with the evolution of the Asian Monsoon. This study provides new insights into the occurrence of EBLFs in East Asia.

关键词： Evergreen broad-leaved forests(EBLFs) Plant fossils East Asia Paleoclimate paleovegetation Asian monsoon

paleovegetational and paleoclimatic evolution series on northeastern Qinghai-Xizang Plateau in the last 30 ka

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Science China Earth Sciences 1996年第6期39卷 640-649页

作者：王富葆阎革Department of Geo-Ocean Sciences Nanjing University Nanjing 210008 China) 韩辉友Department of Geo-Ocean Sciences Nanjing University Nanjing 210008 China) 曹琼英Department of Geo-Ocean Sciences Nanjing University Nanjing 210008 China) 周卫健Department of Geo-Ocean Sciences Nanjing University Nanjing 210008 China) 李升峰Department of Geo-Ocean Sciences Nanjing University Nanjing 210008 China) Department of Geo-Ocean Sciences Nanjing University Nanjing 210008 China)

Palynological study of 2 lacustrine suites by limnological and 14C dating reveals the local evolutionary history of the paleovegetation and the paleoclimate of Zoige Plateau, northeastern Qinghai-Xizang Plateau, since the last 30ka. The territorial paleovegetation evolution experienced 7 stages: alpine desert vegetation, grassland, marsh and sub-alpine meadow, islet forest, marsh and meadow, Picea and Abies forest, marsh and sub-alpine meadow, islet dark conifer, marsh and sub-alpine meadow, and the inferred paleoclimate evolution shared similar variations correspondingly. The major climatic events during the periods of post-glacial and the Holocene left their distinct marks in sediment record.

关键词： Zoige Plateau paleovegetation paleoclimate topsoil pollen distribution.

Fifty years of Quaternary palynology in the Tibetan Plateau

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Science China Earth Sciences 2021年第11期64卷 1825-1843页

作者： Lingyu TANG Caiming SHEN Houyuan LU Chuanhai LI Qingfeng MA Yunnan Key Laboratory of Plateau Geographical Processes and Environmental Changes Faculty of GeographyYunnan Normal UniversityKunming 650500China Nanjing Institute of Geology and Paleontology Chinese Academy of SciencesNanjing 210008China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Nanjing Institute of Geography&Limnology Chinese Academy of SciencesNanjing 210008China CAS Center for Excellence in Tibetan Plateau Earth System Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Quaternary palynology in the Tibetan Plateau(TP)was initiated in the 1960s to meet the needs of economic development in western *** analysis was conducted for the first time on a 200-m long core of Quaternary lacustrine sediments taken from the main body of the TP in order to study pollen assemblages as well as vegetation and climate changes of glacial(cold)/interglacial(warm)*** analysis of alpine snow and ice began at the first scientific expedition to the TP in the *** the 1980s,a series of international collaborative programs were carried out under Sino-French,Sino-German,Sino-Australian,and Sino-American cooperation,marking the integration of Chinese Quaternary palynology society with the international *** methods for Quaternary palynology were gradually promoted and applied,changing the vegetational and climatic interpretation of Quaternary palynology from qualitative to *** the 1990s,many palynologists have carried out extensive Quaternary palynological studies on fossil pollen sites of more than 60 lakes/sections and alpine glaciers in the TP to discuss the spatiotemporal vegetation changes and climatic and environmental evolution of the TP since the *** the past half-century,Quaternary palynology in the TP has contributed to the establishment of the Chinese Quaternary pollen database and the study of vegetation and climate evolution since the Last Glacial Maximum(LGM)in the *** available pollen records revealed the spatial and temporal distribution of vegetation in the TP since the LGM,exhibiting expansions and shrinkages of forest,meadow,grassland and desert in different periods such as the LGM,the last deglaciation,and Holocene optimum *** paleomonsoon reflected by paleovegetation since the LGM has undergone the changes of weak-strengthening-strong-weakening but still active-shrinking,which is mainly affected by solar insolation.

关键词： Tibetan Plateau Lake core Ice core Quaternary palynology paleovegetation Paleoclimate

Pliocene flora and paleoenvironment of Zanda Basin, Tibet, China

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Science China Earth Sciences 2020年第2期63卷 212-223页

作者： Jian HUANG Tao SU Shufeng LI Feixiang WU Tao DENG Zhekun ZHOU CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesXishuangbanna 666303China University of Chinese Academy of Sciences Beijing 100049China Kunming Institute of Botany Chinese Academy of SciencesKunming 650201China Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of SciencesBeijing 100044China Center for Excellence in Life and Paleoenvironment Chinese Academy of SciencesBeijing 100044China

This paper describes a plant megafossil assemblage from the Pliocene strata of Xiangzi, Zanda Basin in the western Qinghai-Tibet Plateau. Twenty-one species belonging to 12 genera and 10 families were identified. Studies show that the Pliocene vegetation in Zanda Basin was mostly deciduous shrub composed of Cotoneaster, Spiraea, Caragana, Hippophae,Rhododendron, Potentilla fruticosa, etc. Leaf sizes of these taxa were generally small. Paleoclimate reconstruction using Coexistence Analysis and CLAMP showed that this area had higher temperature and precipitation in the Pliocene than today, and distinct seasonal precipitation variability was established. The reconstructed paleoelevation of Zanda Basin in the Pliocene was similar to modern times. In the context of central Asian aridification, the gradual drought in the area beginning in the late Cenozoic caused vegetation to transition from shrub to desert, and the flora composition also changed.

关键词： Qinghai-Tibet Plateau Cenozoic Pliocene Plant fossils paleovegetation Paleoclimate Environmental change

Challenges and opportunities in Quaternary palynology

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Science China Earth Sciences 2024年第7期67卷 2148-2161页

作者： Qinghai XU Houyuan LU Zhuo ZHENG College of Geographical Sciences Hebei Key Laboratory of Environmental Change and Ecological ConstructionHebei Normal UniversityShijiazhuang 050024China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China School of Earth Sciences and Engineering Sun Yat-sen UniversityZhuhai 519082China

Quaternary palynology plays a pivotal role in investigating global climate change and various other research fields,serving as an essential tool for the quantitative analysis of paleoenvironment ***,due to the vast diversity of terrestrial ecosystems and intricate interactions between vegetation,climate,and human activities,further advancements are required in the following aspects within this discipline.(1)The accuracy of classification in pollen morphology and fossil pollen identification needs improvement,particularly at the species *** represents a significant challenge in present Quaternary ***-aided intelligent recognition holds promise as a solution for species identification based on more detail pollen morphology.(2)Most pollen-based vegetation and climate reconstructions overlook the significance of bare *** bare ground can lead to substantial inaccuracies when quantitatively reconstructing past vegetation and climate.(3)While pollen records provide reliable information on paleoclimate changes,current quantitative climate reconstruction models heavily rely on modern pollen datasets derived from present-day vegetation disturbed more or less by human *** introduces bias and uncertainties into paleoclimate reconstruction.(4)Although pollen can serve as an indicator of human activities,accurately quantifying the intensity of human influence remains *** accurate identification of crop pollen,reconstructing reliable land cover/use data,and integrating multidisciplinary data may enhance the identification and quantification of signals related to human activity in pollen records.

关键词： Quaternary palynology Paleoclimate paleovegetation Human activity

Evolution of vegetation and climate since the last glacial maximum recorded at Dahu peat site, South China

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Science China Earth Sciences 2007年第8期50卷 1209-1217页

作者： XIAO JiaYi Lü HaiBo ZHOU WeiJian ZHAO ZhiJun HAO RuiHui Department of Geographical Science Nanjing Normal UniversityNanjing 210046China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710075China Department of History and Civilization Weinan Normal UniversityWeinan 714000China

Sporopollen analysis on a 346 cm peat record at Dahu, Jiangxi, chronologically constrained by 16 AMS 14C datings, provides an opportunity to reconstruct the vegetation evolution stages responding to cli-mate change in South China since the last glacial maximum. The result shows that during 18330-15630 cal a B.P., broad-leaved forest dominated the area, corresponding to mild, cool and fairly humid climate. At the interval of 15630-11600 cal a B.P., several evergreen broad-leaved species appeared within the broad-leaved forest, indicating moderate and humid condition. During early Holocene, broad-leaved evergreen forest community was constructed as Castanopsis/Lithorcarpus principally developed, suggesting a warm and humid scenario until 6000 cal a B. P. Since 6000 cal a B. P., abrupt forest deterioration happened with an contemporary increase of fern and herb communities, repre-senting a turnover to relatively cool and dry condition and as well, possible impact from human activi-ties. Meanwhile, several relatively cool and dry events can be identified in the sporopollen record, they can be correlated to the North Atlantic Heinrich event, YD and Holocene millennial-scale oscillations, implying that the low latitude climate was coupled with high latitude influences. Moreover, the varia-tions of temperature and humidity since LGM at Dahu were much smaller when compared with the re-cords in north monsoonal China.

关键词： peat site sporopollen analysis paleovegetation paleoenvironment