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New Benthic Fossils from the Late Ediacaran Strata of Southwestern china

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 311-323页

作者： LIU Junping LI Ming tang Feng ZHAO Jiangtai SONG Sicun ZHOU Ying SONG Xiaohan REN Liudong School of Earth Science and Resources China University of GeosciencesBeijing 10083China Yunnan institute of Geological Survey Kunming 650216China Chinese Academy of Geological sciences Beijing 10037China Key Laboratory for Stratigraphy and paleontology MNRCBeijing 10037China School of Earth Science and Engineering Nanjing UniversityNanjing 210093China Department of Earth sciences University College LondonLondon WC1E 6BTU.K. CAS and Shandong Province Key Laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdaoShandong 266071China institute of geology Chinese Academy of Geological SciencesBeijing 10037China

The Jiangchuan Biota from the Jiucheng Member(Mb.)of the Dengying Formation(Fm.),discovered in Jiangchuan,eastern Yunnan,china,is marked by copious macrofossils at the apex of the Ediacaran *** fauna features benthic algae with varied holdfasts and other fossils of indeterminate taxonomic affinity and is compositionally unique compared to the Shibantan and Gaojiashan biotas of the Dengying *** the Miaohe and Wenghui biotas of the Doushantuo Fm.,elsewhere in *** novel benthic saccular macroalgal fossil,named here Houjiashania yuxiensis *** ***.,from the Jiangchuan Biota is based on fossils that are sausage-shaped,elongate,tubular,ranging from 0.3.to 4 cm in length,and up to 0.8 cm in *** terminus is blunt and rounded to an obtuse angle,the other is bent with a spread-out surface resembling a holdfast,suggesting a three-dimensional ***,stipe-shaped outgrowths,likely vestiges of sessile saccular life forms,are prevalent in macroalgal fossils of analogous size and shape,as well as present brown algae Scytosiphonaceae,such as Colpomenia and *** new findings augment the diversity of benthic algae,such as those known from the Early Neoproterozoic Longfengshan Biota in North *** benthic algal macrofossils in the Jiucheng *** to knowledge of Late Ediacaran metaphyte diversification and offer more clues about the evolutionary positioning of primitive *** co-occurrence of numerous planktonic and benthic multicellular algae and planktonic microbes might have facilitated ecologically the more extensive later Cambrian explosion evidenced by the Chengjiang Biota in Yunnan.

关键词： paleophytology benthic saccular algae algal evolution Neoproterozoic Jiucheng Member Jiangchuan Biota Yunnan Province

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 {2. and {3. 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 2.0-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

An ice-core record of vegetation and climate changes in the central Tibetan Plateau during the last 550 years

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Chinese Science Bulletin 2010年第12期55卷 1169-1177页

作者： YANG Bao tang lingyu LI ChunHai SHAO YaJun TAO ShiCheng YANG LunQing Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China MOE Key Laboratory of West china's Environmental System College of Earth and Environment sciences Lanzhou University Lanzhou 730000 China nanjing institute of {2. and {3. Chinese Academy of Sciences Nanjing 210008 China nanjing institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China

We present a 550-year ice-core pollen record with a 5-year resolution from the Puruogangri ice field in the central Tibetan *** of the relationship between pollen record and instrumental observations suggests that the sum of the steppe and meadow pollen taxa is a good indicator of summer (June-August) temperature,whereas the ratios of Cyperaceae/(Gramineae+Artemisia) [Cy/(G+A)] as well as M/S (meadow to steppe percentages) are indicative of humidity changes in this *** with δ18O and glacial accumulation records,the response of vegetation to climate change over the past 500 years was *** vegetation dominated during 1450-1640 AD,a time period characterized by cold-wet climate,while steppe vegetation expanded during 1640-1915 when warm-dry climate ***,during a cold and humid period,desert vegetation expanded *** 1980-2.02.due to the increase of summer temperatures,steppe and meadow vegetation predominates,while areas with desert vegetation are *** proxy series is the first high-resolution ice-core pollen record spanning the last 550 years for the central Tibetan Plateau.

关键词：沙漠植被青藏高原气候变化中央冰核草甸草原普若岗日冰原夏季气温

Pollen-inferred vegetation and environmental changes since 16.7 ka BP at Balikun Lake, Xinjiang

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Chinese Science Bulletin 2010年第22期55卷 2449-2457页

作者： TAO ShiChen AN ChenBang CHEN FaHu tang lingyu WANG ZongLi LU YanBin LI ZhiFei ZHENG TongMing ZHAO JiaJu MOR Key Laboratory of West china's Environmental System Lanzhou University Lanzhou 730000 China nanjing institute of {2. and {3. Chinese Academy of Sciences Nanjing 210008 China

A high-resolution fossil pollen record from the sedimentary cores of Balikun Lake, northwestern china, combined with modern surface pollen data, is used to reconstruct the history of vegetation and climatic change since 16.7 cal. ka BP. Fossil pollen assem-blages and lithology indicate that the study area was dominated by desert. The desert had extremely arid climate and lower effec-tive moisture during 16.7–7.9 cal. ka BP, especially from 16.7 to 8.9 cal. ka BP when the lake maybe dried up. During 8.9–7.9 cal. ka BP, the environment gradually recovered in this area. It was then followed by the optimum period from 7.9 to 4.3.cal. Ka BP, when the effective moisture obviously increased. It was characterized by the typical desert-steppe/steppe vegetation and was ac-companied with several patch-birch woodlands around the lake. After that, a short but extremely arid climatic event occurred during 4.3.3.8 cal. ka BP, and the vegetation quickly changed from desert-steppe/steppe to desert. It was a relatively optimum period from 3.8 to 0.53.cal. ka BP showing typical desert-steppe/meadow-steppe landscape. Since 0.53.cal. ka BP, the climate has shown signs of deteriorating again. Furthermore, regional comparison shows that the characteristics of climatic and environmental evolution in this area were clearly different from East Asia monsoonal area during the last 16.7 cal. ka BP. It was characterized by the arid climate during the late-glacial and early Holocene, and relatively wet during the mid-late Holocene.

关键词：环境变化巴里坤湖花粉记录 BP 植被中晚全新世新疆气候变化

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江苏南部湖成因演化再研究

江苏地质 1999年第1期23卷 30-33页

作者：邹松梅蒋梦林唐兴元江苏省地质调查研究院江苏金陵地质工程勘察院

记述了湖的基本特征，讨论了全新世镇江海侵对湖的影响，根据全新世各时期沉积物的分布，阐明了湖湖岸的变化；依据古生物与人类活动遗迹资料，指出湖演化发展可分为３个阶段，即距今１００００ａ～６０００ａ为雏形阶段，距今... 详细信息

记述了湖的基本特征，讨论了全新世镇江海侵对湖的影响，根据全新世各时期沉积物的分布，阐明了湖湖岸的变化；依据古生物与人类活动遗迹资料，指出湖演化发展可分为３个阶段，即距今１００００ａ～６０００ａ为雏形阶段，距今６０００ａ～２０００ａ为发展阶段，距今２０００ａ以来为现代湖成形阶段。究其成因为新构造活动—河道淤塞—人工改造而成。

关键词： Ge湖第四系成因演化江苏古湖泊湖泊地貌

Relationship between surface pollen assemblages and vegetation in Luonan Basin, Eastern Qinling Mountains, Central china

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Journal of Geographical sciences 2014年第3期24卷 427-445页

作者： ZHANG Wenchao LI Chunhai LU Huayu TIAN Xianhua ZHANG Hongyan LEI Fang tang lingyu School of Geographic and Oceanographic sciences Nanjing University Jiangsu Collaborative Innovation Center for Climate Change Nanjing 210093 China State Key Laboratory of Lake Science and Environment Nanjing institute of Geography and Limnology CAS Nanjing 210008 China College of Life sciences Shaanxi Normal University Xi'an 710062 China nanjing institute of {2. and {3. CAS Nanjing 210008 China

The catchment of South Luohe River in Central china is an important region for investigating modern pollen-environment relationship, because it is located in the transitional zone between south and north china, an environment which is sensitive to climate changes. In this study, 40 surface samples under ten vegetation types were collected to reveal the relationship between pollen assemblages and vegetation. The results show that the surface pollen assemblages reflect the vegetation quite well. In forest topsoils, the average of arbo- real pollen content is greater than 40%, and the Selaginella sinensis spore is high. As to sparse forest grassland and shrub community, the average arboreal pollen is 13.2. and 16.6% respectively, and the shrub pollen is relatively higher than that of grassland samples. The grassland and farmland are characterized by low percentage of tree and shrub pollen （〈10% and 〈1%）, and high percentage of herbs （〉80%）. Pinus, Quercus and some other arboreal pollen can indicate the regional vegetation because of their dispersal ability. Quercus pollen is under-representative and so is Pinus. Artemisia pollen is significantly over-represented, has poor correlation with the plant coverage, and may reflect human dis- turbance. Gramineae can indicate plant quite well, but with low representation. High content of Chenopodiaceae probably suggests human impact. Predominant Selaginella sinensis can be used as an indicator of forest environment. Cluster analysis and principal components analysis of pollen assemblages can distinguish forest and non-forest vegetation well. The former method is better at separating pine and mixed forests, while the latter is more stable and could better differentiate farmland and other non-forest area. The first axis of PCA mainly reflects the humidity.

关键词： surface pollen vegetation type cluster analysis PCA Luonan Basin

The relationship between fire,vegetation and climate from 6.2.1.3.ka BP,recorded by sediments from Toushe Basin,Taiwan Island

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The relationship between fire,vegetation and climate from 6....

Quantitative Estimates of Climate since the Last Deglaciation from Pollen in Northwest Yunnan,SW china

中国古生物学会孢粉学分会十届二次学术年会

作者： Zhenhui Huang Chunmei Ma Shyh-Jeng Chyi lingyu tang Lin Zhao School of Geography and Ocean Science Nanjing University Jiangsu Collaborative Innovation Center for Climate Change Department of Geography Kaohsiung Normal University nanjing institute of {2. and {3. Chinese Academy of Sciences

We obtained a sedimentary profile from Taiwan’s Toushe *** 12.AMS 14 C samples,we established a reliable stratigraphic *** and charcoal analysis revealed four stages of vegetation,fire and climate between 6.3.1.3.cal ka *** 6.2.4.6 cal ka BP,was a warm and wet period with subtropical evergreen broad-leaved forest and infrequent *** 4.6-3.0 cal ka BP,the climate became cooler and drier with forest declining and regional fires becoming more *** 3.0-2.1 cal ka BP,the EASM continued to weaken,leading to a cooler and drier climate with alpine meadow development,and the dry climate causing high-frequency *** 2.1-1.3.cal ka BP,the climate became warmer and wetter,forest developed and low-levels of of human activity began to impact the *** in climate were closely related to the change of EASM and ENSO.

关键词： pollen 6.3.1.3.cal ka BP vegetation fire EASM ENSO

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Quantitative Estimates of Climate since the Last Deglaciatio...

甘肃北山早白垩世似银杏化石的发现:兼论甘肃侏罗-白垩纪古大气CO_(2.变化

中国古生物学会孢粉学分会十届二次学术年会

作者： Caiming Shen Bin Yin Hongwei Meng Linpei Huang Qifa Sun Qian Zheng Hucai Zhang lingyu tang Chunhai Li Yunnan Key Laboratory of Plateau Geographical Processes and Environmental Changes College of Tourism and Geographical SciencesYunnan Normal University nanjing institute of {2. and {3. Chinese Academy of Sciences nanjing institute of Geography and Limnology Chinese Academy of Sciences

A modern pollen dataset used in this study consists of 75 surface samples from ponds,lakes,and reservoirs in Northwest Yunnan,Southwest *** data for each site,including monthly,seasonal and dry/rainy seasonal,as well as mean annual temperature and precipitation,were derived from observational data（1961-2.10） of 2. meteorological stations in this region using linear interpolation *** correspondence analysis（CCA） was used to reveal the climatic parameters that best reflect the main patterns of variation in this modern pollen dataset,and to detect anomalous *** of CCA indicate that mean annual precipitation（MAP）,precipitation in dry season（November-April）（Pds）,and January temperature（Tjan） are three climatic parameters controlling the variation of this modern pollen dataset in Northwest ***–climate transfer functions for MAP,Pds and Tjan were developed using the weighted-averaging partial least squares（WA-PLS） regression *** to the performance of WA-PLS regression models,3.component WA-PLS models were selected respectively for these three climatic parameters with low RMSEP（the root mean square error of prediction）,low maximum bias,and high coefficient of determination（r2. between observed and predicted values（RMSEP=48.7,17.9 mm,and 1.0 ℃;Maximum Bias=79.8,3..1 mm,and 1.6 ℃;r2.0.6,0.6,and 0.74 for MAP,Pds and Tjan,respectively）.Transfer functions for MAP,Pds and Tjan were then applied to a fossil pollen record from Lugu Lake in Northwest Yunnan to reconstruct paleoclimate in the catchment of this *** estimates of paleoclimate show that MAP and Pds fluctuated around 1000 and 110 mm（their present values）,but Tjan is 0.8-4.3.℃ lower than the present（5 ℃） during 15000-12.00 a BP（cal.a BP）.From 12.00 to 11500 a BP,MAP and Pds were ca.50 and 2. mm higher than the present,and Tjan increased to be the present *** climatic parameters at 11500-9100 a BP reached their maxima throughout the last d

关键词： Quantitative estimates,Climate Pollen,Transfer functions,Northwest Yunnan,Last deglaciation

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地球科学 2024年第1期49卷 209-223页

作者：任文秀韩磊吴光涛唐德亮孙柏年吴靖宇兰州大学地质科学与矿产资源学院甘肃兰州730000 甘肃省地质调查院甘肃兰州730000 现代古生物学和地层学国家重点实验室(中国科学院南京地质古生物研究所) 江苏南京210008

银杏类化石的微细构造是定量估算古大气二氧化碳浓度的良好材料.首次报道了甘肃北山中口子盆地早白垩世赤金堡组似银杏属化石,通过宏观和微观特征对比将其鉴定为Ginkgoites sibirica.利用气孔比率法定量重建Hauterivian-Barremian期的... 详细信息

银杏类化石的微细构造是定量估算古大气二氧化碳浓度的良好材料.首次报道了甘肃北山中口子盆地早白垩世赤金堡组似银杏属化石,通过宏观和微观特征对比将其鉴定为Ginkgoites sibirica.利用气孔比率法定量重建Hauterivian-Barremian期的古大气CO_(2.浓度为766~1 2.7 ppmv.结合前人数据,利用光合气体交换模型定量重建了甘肃省早侏罗世-早白垩世古大气CO_(2.浓度及变化趋势,侏罗纪普林斯巴期(Pliensbachian)、阿林期(Aalenian)、巴柔期早期(Early Bajocian)、巴柔期晚期(Late Bajocian)的古大气CO_(2.浓度分别为1 13. ppmv、92. ppmv、643.ppmv和785 ppmv;早白垩世Hauterivian-Barremian期的CO_(2.浓度为548 ppmv.结果显示早、中侏罗世二氧化碳浓度较高,向白垩纪呈下降趋势,早白垩世早中期达到低点后呈现缓慢波动上升;早白垩世晚期达到顶点,然后缓慢下降.研究表明光合气体交换模型可作为恢复古气候变化的有效手段.

关键词：似银杏属古大气CO_(2. 光合气体交换模型定量重建中生代古气候