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杞麓湖孟氏螺蛳(Anularya mansuyi)壳体碳同位素记录的水体溶解无机碳变化

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湖泊科学 2024年第5期36卷 1436-1446页

作者：江戈平雷国良朱芸张文翔于源许丽红杜垚华李全聪孙婉婷福建师范大学湿润亚热带生态-地理过程教育部重点实验室福州350117 福建师范大学地理科学学院碳中和未来技术学院福州350117 福建师范大学稳定同位素中心福州350117 云南师范大学高原地理过程与环境变化云南省重点实验室昆明650500

湖泊中腹足类壳体碳酸盐的碳同位素与水体溶解无机碳密切相关,是研究区域湖泊水体碳循环的重要材料之一。滇中地区湖泊众多,然而该区域湖泊中水体溶解无机碳的变化特征仍不清楚。孟氏螺蛳壳体为滇中湖泊特有属,本文通过对杞麓湖现生孟... 详细信息

湖泊中腹足类壳体碳酸盐的碳同位素与水体溶解无机碳密切相关,是研究区域湖泊水体碳循环的重要材料之一。滇中地区湖泊众多,然而该区域湖泊中水体溶解无机碳的变化特征仍不清楚。孟氏螺蛳壳体为滇中湖泊特有属,本文通过对杞麓湖现生孟氏螺蛳壳体采集,并对其壳体沿生长方向开展碳酸盐δ~(13)C测试,尝试利用孟氏螺蛳壳体δ~(13)C分析杞麓湖水体溶解无机碳变化的变化特征。研究结果表明:(1)孟氏螺蛳壳体δ~(13)C与壳体生长环境密切相关,QLH-A与QLH-B在母体环境中的δ~(13)C平均值分别为-3.78‰与-5.55‰,变化幅度分别为2.07‰与3.03‰;在湖泊水体环境中的δ~(13)C平均值分别为-2.90‰与-3.28‰,变化幅度分别为1.81‰与1.74‰。(2)孟氏螺蛳在湖泊水体环境中生长时,壳体δ~(13)C记录了湖泊水体DIC的δ~(13)C_(DIC)变化特征,揭示出杞麓湖水体DIC主要受大气交换和湖泊中生物系统共同影响,其δ~(13)C_(DIC)在季节尺度变化不显著。(3)杞麓湖湖泊中大量水生藻类的死亡引起的有机质分解将导致湖泊水体δ~(13)C_(DIC)发生显著偏负变化,据此推断壳体δ~(13)C记录的偏负变化与云南2013年大旱期事件吻合,揭示出孟氏螺蛳壳体δ~(13)C具有记录湖泊生态系统自身重大变化的潜力。孟氏螺蛳古螺壳在滇中湖泊广泛分布,本文研究结果将有利于基于地层中的壳体识别地质历史时段滇中湖泊水体DIC特征及其湖泊生态系统的变化。

关键词：杞麓湖孟氏螺蛳碳同位素水体溶解无机碳

Discovery of bacteriopheophytin-a in lacustrine deposits from Lake Zigetang on the central Tibetan Plateau and its paleoenvironmental significance

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Science China Earth Sciences 2017年第12期60卷 2171-2180页

作者： LI HuaYong ZHANG HuCai CHANG FengQin ZHENG Qian ZHANG WenXiang lei guoliang lei YanBin PU Yang JI JunFeng Key Laboratory of Plateau Lake Ecology and Global Change Yunnan Provincial Key Laboratory of Plateau Geography Process and Environment ChangesCollege of Tourism and Geography ScienceYunnan Normal UniversityKunming 650500China School of Resource Environment and Tourism Anyang Normal UniversityAnyang 455000China College of Urban and Environment Sciences Central China Normal UniversityWuhan 430079China Key Laboratory for Subtropical Mountain Ecology(Ministry of Science and Technology and Fujian Province Funded) Fujian Normal UniversityFuzhoa 350007China Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100085China School of Remote Sensing Nanjing University of Information Science&TechnologyNanjing 210044China Institute of Surface Geochemistry Department of Earth SciencesNanjing UniversityNanjing 210093China

Lake Zigetang is located on the central Tibetan Plateau(TP) and represents a rare but typical meromictic lake in *** lake's stable meromixis sustains microflora communities, and changes in these communities are relatively independent of climate. Therefore, these communities can be used as paleoclimate proxies. In this paper, the stratification properties and their relationships with the microflora of Lake Zigetang were analyzed. We found that water depth and climate conditions were two important factors for maintaining meromixis in Lake Zigetang. Generally, stratification was enhanced during warm periods, while temperature differences between the mixolimnion and monimolimnion were decreased during cold periods. The presence of anoxygenic phototrophic bacteria(APB) was demonstrated by the discovery of bacteriopheophytin-a(Bph-a) in the *** bacterial community is mainly concentrated at the bottom of the chemocline and the top of the monimolimnion, where it forms a thin APB layer. Moreover, total APB productivity is mainly affected by the light intensity penetrating to the APB layer,which exponentially increases as the thermocline becomes shallow. Therefore, high Bph-a values in the lake corresponded to a shallow thermocline and warm periods, low Bph-a values corresponded to cold periods, and zero changes indicated that the water was completely mixed and reflected an extreme cold climate or low lake level period. Thus, Bph-a can be used as a climate proxy to reconstruct the history of lake stratification and climate changes.

关键词： Lake Zigetang Tibetan Plateau Meromictic lakes Thermocline Anoxygenic phototrophic bacteria

On Polynomial Dichotomy of Linear Discrete-Time Systems in Banach Spaces

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Journal of Mathematical Research with Applications 2015年第5期35卷 543-550页

作者： Tian YUE guoliang lei School of Science Hubei University of Automotive Technology

This paper deals with two concepts of polynomial dichotomy for linear difference equations which are defined in a Banach space and whose norms can increase not faster than *** illustrating examples clarify the relations between these *** approach is based on the extension of techniques for exponential dichotomy to the case of polynomial *** obtained results are generalizations of well-known theorems about the exponential stability and exponential dichotomy.

关键词： linear discrete-time systems uniform polynomial dichotomy polynomial dichotomy

Geochemical fractionation of rare earth elements in lacustrine deposits from Qaidam Basin

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Science China Earth Sciences 2009年第11期52卷 1703-1713页

作者： ZHANG HuCai ZHANG WenXiang CHANG FengQin YANG LunQing lei guoliang YANG MingSheng PU Yang lei YangBin Key Laboratory of Western China’s Environments MOECollege of Earth Sciences and EnvironmentsLanzhou UniversityLanzhou 730000China State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China Key Laboratory of Boyang Lake MOESchool of Environmental and Chemical EngineeringNanchang UniversityNanchang 330031China

Based on the concentration and distribution pattern analysis of the rare earth elements (REEs) at the Shell Bar section from Qaidam Basin, we studied the geochemical fractionations of REE in paleolake deposits and their paleo-environmental significance. Our results show that the REE concentration in AS (acid soluble) and AR (acid residual) fractions are 20.9 μg/g and 95.4 μg/g (except element Y) individually, showing a strong REE differentiation between AS and AR fractions. However, the two types of fractions (AS & AR) have similar REE distribution patterns, which are slightly rich in light earth rare elements (LREEs), with slightly right-tilting and negative Eu anomaly. The LREE of AR is richer than that of AS. There were no significant correlations between the REE in AS, AR and other proxies. It indicated that the lacustrine deposition had different material sources and experienced varying geochemical procedures. Correlation analysis between the REE and the content of fine grain-size (<4 μm) of the sediments, Rb/Sr ratio and Mn concentration showed high correlation coefficients. Our results demonstrated that the REE in acid soluble and residual fractions bear different environmental significances, which are strongly dependent on local environment. The REE of acid soluble fraction is closely related to the paleoclimatic changes in the lake catchment and the evolutionary processes of lake itself. Our results suggest that δCe and (La/Yb)n could be used as proxies of the reduction-oxidation conditions and furthermore the temperature change and the lake level fluctuations. Using these proxies, we reconstructed the paleoclimate and water level fluctuation history during the high lake level period lasting between 43.5 and 22.4 cal. ka BP.

关键词： Shell Bar section rare earth elements (REE) fractionation paleoclimate Qaidam Basin

Climate variability recorded by n-alkanes of paleolake sediment in Qaidam Basin on the northeast Tibetan Plateau in late MIS3

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Science China Earth Sciences 2010年第6期53卷 863-870页

作者： PU Yang ZHANG HuCai lei guoliang CHANG FengQin YANG MingSheng ZHANG WenXiang lei YanBin YANG LunQing PANG YouZhi State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China Graduate University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Boyang Lake MOESchool of Environmental and Chemical EngineeringNanchang UniversityNanchang 330031China

Here we combine n-alkanes preserved in a shell bar section from Qarhan paleolake, Qaidam Basin with the other sedimentary proxies to elucidate the lake evolution process during the period 39.7 to 17.5 14C ka BP (calibrated age ranges from 43.5 to 22.4 cal. ka BP). In different stages, the n-alkane homologues exhibited different distribution modes indicative of variations in the surrounding vegetation and the hydrologic condition of the lake. The n-alkanes proxies (CPIh, ACLh, Paq) have the same trends as the summer solar insolation variation, implying that the summer insolation is the most important climatic factor driving the environmental changes and also indirectly controls lake evolution on the Tibetan Plateau. CPIh and ACLh as well as the total pollen concentration appear to show a trend comparable with methane concentration record from the GRIP ice core that reflected the Dansgaard-Oeschger events. This demonstrates that the paleoclimate variations in Qarhan area generally agree with global climate change and show rapid oscillations in late MIS3. These findings provide the latest molecular fossil evidence from paleolake sediments to confirm that lake evolution on Tibetan Plateau in late MIS3 was closely associated with enhanced summer insolation.

关键词： paleolake sediment molecular fossil n-alkane paleoclimate paleoenvironment solar insolation

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

Climatic and environmental implications from n-alkanes in glacially eroded lake sediments in Tibetan Plateau:An example from Ximen Co

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Chinese Science Bulletin 2011年第14期56卷 1503-1510页

作者： PU Yang ZHANG HuCai WANG YongLi lei guoliang NACE Trevor ZHANG ShuPing School of Remote Sensing Nanjing University of Information Science & Technology Nanjing 210044 China State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008. China Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences. Lanzhou 730000 China Duke University. Divisio. of Earth and Ocean Sciences Durham. North Carolina 27708-0227. USA

Gas chromatography-mass spectrometry was used to identify a series of n-alkanes in the sediments of a typical glacially eroded lake in the eastern Tibetan *** comparing the distribution patterns of n-alkanes in lake sediments,surface soils and cow manure,it was shown that n-C 27-n-C 33 alkanes in the soil ecosystem of Ximen Co are derived from vascular plant species and that the distribution pattern of n-C 27-n-C 33 alkanes remains unchanged during the feeding and digestion processes of *** relative percentage of C 27,C 29 and C 31 n-alkanes decreased from the bottom to the top of the sediment core showing a trend of degradation of higher plants in the Ximen Co lake region during the formation of the 44 cm core.210 Pb dating,combined with pre-existing AMS 14 C dating results showed that the depositional core reflects climatic and environmental variations since about 900 years before *** n-alkane indexes (ACL 27-33,P aq,P wax) are comparable with regional temperature variation,especially recording the Little Ice Age event (LIA).This study highlights that n-alkanes are valid proxies for paleo-climate and paleo-environment reconstruction,despite the same distribution patterns in n-alkane molecular fossils derived from a typical glacially eroded lake.

关键词：湖泊沉积物青藏高原东部正构烷烃环境变化古气候侵蚀冰川合作

^(10)Be in quartz gravel from the Gobi Desert and evolutionary history of alluvial sedimentation in the Ejina Basin,Inner Mongolia,China

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Chinese Science Bulletin 2010年第33期55卷 3802-3809页

作者： LU YanWu GU ZhaoYan ALDAHAN Ala ZHANG HuCai POSSNERT Goran lei guoliang Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Department of Earth Sciences Uppsala University Uppsala S-75236 Sweden Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China Tandem Laboratory Uppsala University Uppsala S-75121 Sweden

Reconstructing the evolutionary history of the Gobi deserts developed from alluvial sediments in arid regions has great significance in unraveling changes in both tectonic activity and ***,such work is limited by a lack of suitable dating material preserved in the Gobi Desert,but cosmogenic 10Be has great potential to date the Gobi *** the present study,10Be in quartz gravel from the Gobi deserts of the Ejina Basin in Inner Mongolia of China has been measured to assess exposure *** show that the Gobi Desert in the northern margin of the basin developed 420 ka ago,whereas the Gobi Desert that developed from alluvial plains in the Heihe River drainage basin came about during the last 190 *** latter developed gradually northward and eastward to modern terminal lakes of the *** temporal and spatial variations in the Gobi deserts are a consequence of alluvial processes influenced by Tibetan Plateau uplift and tectonic activities within the Ejina *** episodes of Gobi Desert development within the last 420 ka indicate that the advance/retreat of alpine glaciers during glacial/interglacial cycles might have been the dominant factor to influencing the alluvial intensity and water volume in the *** floods and large water volumes would mainly occur during the short deglacial periods.

关键词：额济纳盆地戈壁沙漠冲积物内蒙古石英中国演化史沉积

Diatom Response to Global Warming in Douhu Lake,Southeast China

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Acta Geologica Sinica(English Edition) 2021年第2期95卷 638-647页

作者： LI Jingjing WANG Luo CAO Qi Patrick RIOUAL lei guoliang CAI Binggui ZHANG Jiaoyang ZOU Yafei YAN Yao WAN Xiaoqiao XIAO Jule School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China School of Geographical Sciences Fujian Normal UniversityFuzhou 350007China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China Key Laboratory of Humid Subtropical Ecogeographical Processes of the Ministry of Education Fujian Normal UniversityFuzhou 350007China Institute of Geography Fujian Normal UniversityFuzhou 350007China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

A large number of lacustrine sedimentary records indicate that global warming is the main factor leading to significant changes in diatom communities in lakes of the northern ***,due to the intensification of human activities since 1850,some scholars have emphasized that the increasing lake trophic level may be the main reason for the changes in diatom *** debate is *** order to avoid falling into the complex relationship between diatom changes and the seasonal cycle that characterizes lakes in mid and high latitudes,we chose a lake located at a low latitude,where the relationship between diatoms and temperature is not indirect but *** diatom record spans the past ca.100 years and reveals that the abundance of Aulacoseira granulata increased from 1900 until 1985,replacing the previously dominant Aulacoseira *** changes are in agreement with the increasing trend in global *** 1985,the percentages of the small-celled Discostella stelligera and the benthic diatom Navicula heimansioides have increased,while Aulacoseira granulata has *** latest shift is caused by further global *** conclude that warming is the main factor leading to changing diatom communities in Douhu Lake.

关键词： diatom global warming Douhu Lake China