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An annually laminated stalagmite from the eastern Qinghai-Tibetan Plateau provides evidence of climate instability during the early MIS5e in the Asian summer monsoon

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Science China Earth Sciences 2023年第5期66卷 1147-1164页

作者： Tao GAO Pingzhong ZHANG Hai CHENG Leilei ZHANG Xinhu LI Hongyu SHI Wei JIA Youfeng NING Hanying LI r.lawrence edwards Key Laboratory of Mineral resources in Western China(Gansu Province)and School of Earth Sciences Lanzhou UniversityLanzhou730000China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an710054China Department of Earth Sciences University of MinnesotaMinneapolis55455USA

The Marine Isotope Stage(MIS5e)is characterized by a warmer climate than that of the pre-industrial period,and serves as an analog for the Current Warm Period(CWP).However,uncertainties persist regarding its climatic ***,we retrieved a stalagmite(WXB075)from Wanxiang Cave in the eastern Qinghai-Tibetan Plateau,and employed abs-olute^(230)Th dating and relative annual layer data to establish a high-precision chronological framework for reconstructing the history of the Asian summer monsoon(ASM)and environmental evolution during early MIS5e with multiple *** findings indicate that the annually laminated stalagmite was formed during Cooling Event 27(C27).The deposition of WXB075 experienced a hiatus(~125.58 ka BP)due to a significant cooling event in the North Atlantic,which may be linked to the unstable climate in the Northern ***,the impact of meltwater discharge in high northern latitudes results in a two-phase evolution of the ASM,i.e.,an initial weaker stage followed by a gradual increase(with exception of deposition hiatus).The climatic instability of ASM is generally characterized by a quasi-60 year cycle that affects vegetation conditions,biological productivity,and karst hydroclimate ***,the increase in meltwater and decrease in temperature in the Northern Hemisphere have led to a weakened ASM and subsequent reduction in ***,vegetation degradation above the cave has occurred along with a slowdown of karst *** vegetation conditions,organic matter content,and wet/drought of the karst hydroclimate were affected by both the large-scale monsoon circulation and local environment during extreme weakening(strengthening)of the monsoon when high-frequency climatic events of ASM occurred.A comparison ofδ^(18)O records between early MIS5e and the past 2000 years reveals that the climate during early MIS5e differed significantly from that of CWP,Medieval Warm Period(MWP),and Dark Age Co

关键词： Eastern Qinghai-Tibetan Plateau Climate instability Wanxiang Cave stalagmite Asian summer monsoon Environmental response Deposition hiatus

Summer Monsoon rainfall Variability in Central China over the Past 4700 Years and Its Possible Link to Solar Activity

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Journal of Meteorological research 2021年第4期35卷 594-606页

作者： Jingwei ZHANG Kan ZHAO Xinggong KONG Yongjin WANG Xianfang WANG Shushuang LIU Zhenjun WANG Hai CHENG r.lawrence edwards School of Geography and Environment Jiangxi Normal UniversityNanchang 330022China School of Geography Science Nanjing Normal UniversityNanjing 210023China Key Laboratory ofPoyang LakeWetland and Watershed research of Ministry of Education Jiangxi Normal UniversityNanchang 330022China Lanling NO.4 Middle School Linyi 277700China Institute of Global Environmental Change Xi'an Jiaotong UniversityXi'an 710049China Department of Geology and Geophysics University of MinnesotaMinneapolis MN55455USA

Based on 467 pairs ofδ^(18)O andδ^(13)C records and 8230 Th dates from a stalagmite(BF4)from Xiniu Cave,central China,we present a reconstruction of 9-yr resolution monsoon rainfall record for the past 4700 ***δ^(18)O record shows good coherence with East Asian summer monsoon(EASM)rainfall proxies from adjacent regions during the overlapping intervals,suggesting thatδ^(18)O signal in BF4 can be interpreted as a monsoon rainfall ***δ^(13) C variations are related to changes in local processes at the cave site,and regional rainfall and temperature *** on theδ18 O record,a series of dry periods can be identified at 4500-4200,3500-3200,2800-2500,1900-1600,1400-1200,700-500,and 400-200 yr BP,while a series of wet periods can be identified at 4200-3600,2400-2200,3200-2800,1100-900,600-400,and 200-100 yr *** spectrum analysis on ourδ^(18) O record reveals significant cycles at 470 and 80 yr,coinciding with the typical solar periodic *** result suggests that changes in solar activity play a dominant role in driving centennial-decadal monsoon rainfall variation in central *** to minor changes in solar irradiance(less than 1.5 W m^(-2))over the past 4700 years,our record was further compared to the El Nino-Southern Oscillation(ENSO)and Pacific Decadal Oscillation(PDO)proxies,confirming that solar forcing on monsoon rainfall changes might be amplified by the ENSO and PDO *** 600 to 150 yr BP(the Little Ice Age,LIA),a positive shift of 2‰can be revealed in both theδ^(18)O andδ^(13)C records,indicating a cold/dry climatic *** comparing ourδ^(18)O andδ^(13)C records with historical documents,we suggest that the climatic deteriorations between 450 and 250 yr BP may have caused serious social unrest at the end of the Ming Dynasty.

关键词： stalagmite record Xiniu Cave solar activity El Nino-Southern Oscillation(ENSO) Pacific Decadal Oscillation(PDO) amplify mechanism Little Ice Age(LIA)

Application of Avaatech X-ray fluorescence core-scanning in Sr/Ca analysis of speleothems

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Science China Earth Sciences 2019年第6期62卷 964-973页

作者： Dong LI Liangcheng TAN Fei GUO Yanjun CAI Youbin SUN Gang XUE Xing CHENG Hong YAN Hai CHENG r.lawrence edwards Yongli GAO Jessica KELLEY State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences University of Chinese Academy of Sciences Center for Excellence in Quaternary Science and Global Change Chinese Academy of Sciences Institute of Global Environmental Change Xi'an Jiaotong University Open Studio for Oceanic-Continental Climate and Environment Changes Pilot National Laboratory for Marine Science and Technology Department of Earth Sciences University of Minnesota Department of Geological Sciences University of Texas at San Antonio

Application of X-ray fluorescence core-scanning(XrF-CS) on both marine and lake sediments has achieved remarkable results. However, its application has not been widely extended to the research on speleothems. In this study, we measure the Sr abundance and the Sr/Ca ratios of three stalagmites(two aragonite stalagmites, one calcite stalagmite) using the state-of-the-art fourth-generation Avaatech high-resolution XrF core scanner. Through comparisons among different scan paths and among different scan resolutions, as well as comparisons with inductively coupled plasma optical emission spectrometer(ICP-OES), Itrax XrF, and Artax XrF results, we confirm that the Avaatech XrF core scanner could precisely, quickly, and nondestructively analyze the high-resolution Sr abundance of speleothems. Furthermore, we combine the stalagmite δ^(18)O records to explore the paleoclimatic significance of the measured stalagmite Sr/Ca.

关键词： Avaatech XrF Speleothem Sr/Ca Paleoclimate

A dry episode during the Younger Dryas and centennial-scale weak monsoon events during the early Holocene:A high-resolution stalagmite record from southeast of the Loess Plateau,China

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A dry episode during the Younger Dryas and centennial-scale ...

末次冰消期亚洲季风突变事件的精确定年:以贵州衙门洞石笋为例

中国科学院地质与地球物理研究所2008学术年会

作者： r.lawrence edwards Department of Geology and Geophysics University of MinnesotaMinnesotaUSA.

[1]A high-resolution stalagmite oxygen isotope record from Dongshiya Cave,located southeast of the Chinese Loess Plateau,reveals detailed climatic oscillations between 12.7 and 9.0 ka BP,on centennial and decadal timescales, with a temporal resolution of 1 to 20 *** early Younger Dryas is characterized by a gradual increase inδO values,which is followed by a depositional hiatus for the remainder of the Younger Dryas,between 12.1 and 11.5 ka BP,implying a weak East Asian Monsoon or a dry climate during the Younger *** weak monsoon events between 11.5 and 9.0 ka BP punctuate the early Holocene East Asian Monsoon,and are likely tied to cold events in Greenland,including the Pre-boreal Oscillation and the 9.2 ky *** spectral analysis of the DongshiyaδO time series yields peaks at frequencies that have been linked to solar frequencies,indicating that solar changes may be,at least partially,responsible for changes in the intensity of the East Asian Monsoon during the early Holocene.

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中国科学（D辑） 2010年第2期40卷 199-210页

作者：杨琰袁道先程海张美良覃嘉铭林玉石朱晓燕 r.lawrence edwards 西南大学地理科学学院重庆400715 中国地质科学院岩溶地质研究所国土资源部岩溶动力学重点实验室桂林541004 Department of Geology and Geophysics University of Minnesota

通过贵州衙门洞Y1石笋33个U/Th年龄和1020个氧同位素数据的分析,重建了西南地区末次冰消期至全新世早期(16.2～7.3kaBP)平均分辨率达9a的亚洲夏季风演化特征.该时段发生的气候突变事件,在Y1石笋记录中得到明显揭示,类似格陵兰冰芯记录的... 详细信息

通过贵州衙门洞Y1石笋33个U/Th年龄和1020个氧同位素数据的分析,重建了西南地区末次冰消期至全新世早期(16.2～7.3kaBP)平均分辨率达9a的亚洲夏季风演化特征.该时段发生的气候突变事件,在Y1石笋记录中得到明显揭示,类似格陵兰冰芯记录的GI-1e～GI-1a事件(GIS)可以定义末次冰消期亚洲季风突变事件的中国基准(CIS)为A.1e～A.1a,Y1石笋δ18O值记录这些事件的开始时限分别为:(14750±50),(14100±60),(13870±80),(13370±80)和(12990±80)aBP;A.1a结束进入YD事件为(12850±50)aBP,YD结束进入全新世为(11500±40)aBP,其中BA转换(A.1e开始)和YD转换前后δ18O值有3‰的变幅.Y1记录区域对比表明亚洲季风在早全新世期间总体增强的趋势在各地区并没有显著的相位差异,因而不支持东亚和印度季风在轨道尺度上的反相位关系.Y1记录支持近10年来石笋研究的结果,即亚洲季风气候变化的驱动机制除了主导的太阳辐射、大西洋径向环流(MOC)及热带辐合带(ITCZ)运移外,短尺度上的季风变化和太阳活动密切相关.

关键词：石笋亚洲季风末次冰消期全新世铀系法定年 l衙门洞

A multiple-proxy stalagmite record reveals historical deforestation in central Shandong, northern China

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Science China Earth Sciences 2020年第11期63卷 1622-1632页

作者： Liangcheng TAN Wen LIU Tianli WANG Peng CHENG Jingjie ZANG Xiqian WANG Le MA Dong LI Jianghu LAN r.lawrence edwards Hai CHENG Hai XU Li AI Yongli GAO Yanjun CAI State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Center for Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710049China Open Studio for Oceanic-Continental Climate and Environment Changes Pilot National Laboratory for Marine Science and TechnologyQingdao 266061China 801 Institute of Hydrogeology and Engineering Geology Shandong Provincial Bureau of Geology&Mineral ResourcesJinan 250014China Shandong Engineering research Center for Environmental Protection and remediation on Groundwater Jinan 250014China Library of Chang’an University Xi’an 710064China Department of Earth Sciences University of MinnesotaMinneapolis MN 55455USA School of Geography Nanjing Normal UniversityNanjing 210097China Institute of Surface-Earth System Science Tianjin UniversityTianjin 300072China Department of Geological Sciences University of Texas at San AntonioSan Antonio TX 78249USA

Evaluating anthropogenic impacts on regional vegetation changes during historical time is not only important for a better understanding of the Anthropocene but also valuable in improving the vegetation-climate *** this study,we analyzed stable isotopes(δ^18O,δ^13C)and trace elements(Mg/Ca,Sr/Ca)of a stalagmite from Huangchao Cave in central Shandong,northern China.230Th and AMS14C dating results indicate the stalagmite deposited during 174BC and AD1810,with a hiatus between AD638 and *** similarities of theδ^18O and trace elements in the stalagmite suggest they are reliable precipitation ***δ^13C of the stalagmite,a proxy of vegetation change,was generally consistent with local precipitation and temperature variations on a centennial-scale before the 15th *** typically varied from–9.6‰to–6.3‰,indicating climate controlled C3 type vegetation during this ***,a persistent and marked increasing trend in theδ^13C record was observed since the 15th century,resulting inδ^13C values from–7.7‰to–1.6‰in the next four *** unprecedentedδ^13C change caused by vegetation deterioration cannot be explained by climate change but is fairly consistent with the dramatically increasing population and farmland in *** suggest that the increasing deforestation and reclamation in central Shandong began to affect vegetation in the mountain region of central Shandong since the 15th century and severely destroyed or even cleared the forest during the 16th–18th century.

关键词： Speleothem Stable isotopes Trace elements Deforestation Human activity 16th century

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贵州七星洞石笋文石-方解石序列记录的气候变化

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地球环境学报 2021年第6期12卷 632-640页

作者：黄守毅蔡演军吕雁斌贺梅成星程海 r.lawrence edwards 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710061 中国科学院大学北京100049 西安交通大学全球环境变化研究院西安710054 中国科学院第四纪科学与全球变化卓越创新中心西安710061 Department of Earth Sciences University of MinnesotaMinneapolis 55455USA

文石-方解石型石笋的矿物相变化可能与气候环境变化存在联系,但中国季风区有关此类石笋的古气候研究比较匮乏。本文对七星洞一个文石-方解石型石笋开展了岩石学鉴定和氧、碳同位素组成分析,发现其文石层的出现与δ^(18)O值、δ^(13)C值... 详细信息

文石-方解石型石笋的矿物相变化可能与气候环境变化存在联系,但中国季风区有关此类石笋的古气候研究比较匮乏。本文对七星洞一个文石-方解石型石笋开展了岩石学鉴定和氧、碳同位素组成分析,发现其文石层的出现与δ^(18)O值、δ^(13)C值的显著偏正存在联系,通过对文石形成的可能机制和δ^(18)O、δ^(13)C值变化的一般规律进行综合分析,验证了该类石笋中文石层出现指示气候干旱的论点。将石笋校正后的方解石δ^(18)O序列与董哥洞δ^(18)O记录进行对比,发现七星洞石笋QXZ文石层指示的干旱事件与董哥洞记录中的弱季风事件存在一定的对应关系,因此,研究该类型石笋的矿物相变化对于全面认识研究区季风变化历史具有重要意义。

关键词：石笋方解石文石 δ^(18)O 气候变化

青藏高原东部MIS5e早期亚洲夏季风气候不稳定性的年纹层石笋印迹

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中国科学：地球科学 2023年第5期53卷 1143-1162页

作者：高涛张平中程海张磊磊李新虎石宏宇贾伟宁有丰李瀚瑛 r.lawrence edwards 兰州大学地质科学与矿产资源学院甘肃省西部矿产资源重点实验室兰州730000 西安交通大学全球环境变化研究院西安710054 Department of Earth Sciences University of MinnesotaMinneapolisMN 55455USA

深海同位素5e阶段(Marine Isotope Stage,MIS5e)是比工业化前更温暖的气候时期,这一阶段的气候可为当代暖期(Current Warm Period,CWP)气候提供“气候变化的过去相似型”,但MIS5e时期气候内部稳定状况仍然不清楚.我们从青藏高原东部万... 详细信息

深海同位素5e阶段(Marine Isotope Stage,MIS5e)是比工业化前更温暖的气候时期,这一阶段的气候可为当代暖期(Current Warm Period,CWP)气候提供“气候变化的过去相似型”,但MIS5e时期气候内部稳定状况仍然不清楚.我们从青藏高原东部万象洞内采集到一根石笋WXB075,通过U-Th和纹层计数年代数据建立了该石笋生长的高精度年代模型,并利用多替代指标重建了MIS5e早期亚洲夏季风变迁与环境演化历史.结果显示,年纹层石笋WXB075生长于MIS5e早期的北大西洋C27(Cooling Event 27,C27)降温时期.受北大西洋降温的显著影响,该石笋生长被打断(沉积间断;~125.58ka BP),并可能与北半球气候不稳定状况有关.此外,由于北高纬冰融水排放的强烈作用,石笋WXB075δ^(18)O记录的MIS5e早期亚洲夏季风可定义为两个阶段:较弱阶段和逐步增强阶段(间断除外).总体上,亚洲夏季风气候不稳定性以准60a为循环周期,调控洞穴上覆植被状况、生物生产力变化和喀斯特动态水循环.然而,当北高纬冰融水排放加剧和温度降低时,亚洲夏季风强度减弱和降雨量大幅度减少并导致洞穴上覆植被退化和岩溶动态水循环减缓.而当亚洲夏季风高频气候事件发生时,洞穴上覆植被状况、有机质含量和喀斯特动态水循环干湿变化不仅受大尺度季风环流状况的显著影响,也深受局域环境的强烈作用.将MIS5e早期δ^(18)O记录与过去2000年以来δ^(18)O记录对比发现,MIS5e早期与CWP、中世纪暖期(Medieval Warm Period,MWP)和黑暗冷期(Dark Age Cold Period,DACP)亚洲夏季风存在镜像关系,而与小冰期(Little Ice Age,LIA)具有一定的相似性.通过与北半球其他地质记录对比,发现MIS5e时期气候不稳定性具有普遍性.功率谱结果显示,石笋WXB075MIS5e早期δ^(18)O记录具有显著的准60a和35a周期信号,与北大西洋多年代际涛动(Atlantic Multi-decadal Oscillation,AMO)周期一致.综合结果表明,MIS5e早期亚洲夏季风与太阳活动变化密切相关,并对热带复合带位置(Intertropical Convergence Zone,ITCZ)和大西洋径向翻转环流(Atlantic Meridional Overturning Circulation,AMOC)响应敏感.

关键词：青藏高原东部气候不稳定性万象洞石笋亚洲夏季风环境响应沉积间断

Human activity and climate change triggered the expansion of rocky desertification in the karst areas of Southwestern China

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Science China Earth Sciences 2021年第10期64卷 1761-1773页

作者： Chaojun CHEN Daoxian YUAN Hai CHENG Tsailuen YU Chuanchou SHEN rlawrence edwards Yao WU Siya XIAO Jian ZHANG Tao WANG ran HUANG Ziqi LIU Tingyong LI Junyun LI Chongqing Key Laboratory of Karst Environment School of Geographical SciencesSouthwest UniversityChongqing 400715China Key Laboratory of Karst Dynamics MNRGuangxiInstitute of Karst GeologyChinese Academy of Geological SciencesGuilin 541004China Yunnan Key Laboratory of Plateau Geographical Processes&Environmental Changes Faculty of GeographyYunnan Normal UniversityKunming 650500China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710049China High-precision Mass Spectrometry and Environment Change Laboratory(HISPEC) Department of GeosciencesTaiwan UniversityTaipei 10617China research Center for Future Earth Taiwan UniversityTaipei 10617China Global Change research Center Taiwan UniversityTaipei 10617China Department of Earth Sciences University of MinnesotaMinneapolisMN 55455USA Environnements et Paléoenvironnements Océaniques et Continentaux(EPOC) UMR CNRS 5805Universitéde BordeauxPessac 33600France School of Karst Science Guizhou Normal UniversityGuiyang 550001China

It is conducive to the sustainable development of human beings in karst regions to research the mechanism of karst rocky desertification(KrD)*** the large-scale KrD in southwestern China is caused by climate change or human activities is still *** this study,the evolution of the KrD in southwestern China over the past 2000 years was reconstructed through the high-precisionδ^(13)C record of stalagmites from Shijiangjun(SJJ)Cave,Guizhou Province,***δ^(13)C of the stalagmites from SJJ Cave exhibited heavy values from the Medieval Warm Period(MWP)to the Little Ice Age(LIA).Furthermore,theδ^(13)C records of other stalagmites and tufa from southwestern China also showed the same significant heavy *** the stalagmiteδ^(13)C could record the change of ecological environment,it indicated that the consistent change of the stalagmitesδ^(13)C may record the process of KrD expansion in the karst regions of southwestern *** the MWP,the stronger Asian summer monsoon and the northward movement of the rain belt led to a dry period in southwestern China and a wet period in northern *** contrast,it was wet in southwestern China and dry in northern China during the *** addition,after the Jing-Kang event(JK event,AD1127)occurred at the end of the Northern Song dynasty,the political and economic center of China migrated to southern China for the first time,which changed the population distribution pattern of larger population in the north and smaller population in the ***,the expansion of KrD in southwestern China was exacerbated in the MWP due to the change of climate in southwestern China,the migration of a large number of people,wars,the large-scale reclamation of arable land,and the cultivation of large areas of crops.

关键词： Karst rocky desertification Jing-Kang event Stalagmiteδ13C record Medieval Warm Period Little Ice Age