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三原黄土中支链甘油单烷基甘油四醚类化合物的检出及其环境指示意义

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第四纪研究 2024年第5期44卷 1308-1321页

作者：潘高超张师豪杨石岭中国科学院地质与地球物理研究所中国科学院新生代地质与环境重点实验室北京100029 中国科学院大学地球与行星科学学院北京100049

来源于古菌和细菌的甘油二烷基甘油四醚(GDGTs)是重建古环境的重要指标。近年来,在培养菌、海洋、河流、湖泊和泥炭中检出了甘油单烷基甘油四醚类化合物(GMGTs或H-GDGTs),其中,支链甘油单烷基甘油四醚类化合物(brGMGTs或H-brGDGTs)的存... 详细信息

来源于古菌和细菌的甘油二烷基甘油四醚(GDGTs)是重建古环境的重要指标。近年来,在培养菌、海洋、河流、湖泊和泥炭中检出了甘油单烷基甘油四醚类化合物(GMGTs或H-GDGTs),其中,支链甘油单烷基甘油四醚类化合物(brGMGTs或H-brGDGTs)的存在被认为与高温环境有关。目前,brGMGTs在黄土中的分布特征和环境指示意义还不明确。三原黄土剖面(34.70°N,109.04°E)位于黄土高原中南部,剖面深度为17.1 m,年龄跨度为0~219 ka,涵盖S_(0)、L_(1)、S_(1)、L_(2)和S_(2-1)等地层单元。三原黄土剖面地层连续性好、分辨率高,是开展brGMGTs研究的理想材料。本研究选取了三原黄土剖面中72个黄土和古土壤样品,通过高效液相色谱-大气压化学电离-质谱/质谱,确认了黄土高原的黄土中存在brGMGT-1020、brGMGT-1034和brGMGT-1048这3种brGMGTs;brGMGTs的含量与GDGTs中的Ⅰa、Ⅱa和Ⅲa相关,这表明brGMGT-1020、brGMGT-1034和brGMGT-1048可能分别是由Ⅰa、Ⅱa和Ⅲa在微生物的作用下转化而来。三原黄土剖面中的brGMGTs相对含量与剖面深度/样品年龄正相关,这种关系可能是沉积后的物理化学过程导致的。在沉积年龄小于40 ka的黄土和古土壤中,brGMGTs相对含量的变化可以在一定程度上反映气候环境特征,较高的brGMGTs相对含量可能对应温度较高的时段。brGMGTs有潜力成为指示古增温事件的生物标志物。

关键词：中国黄土支链甘油单烷基甘油四醚类化合物(brGMGTs或H-brGDGTs) 生物标志物

The East Asian Monsoon since the Last Glacial Maximum:Evidence from geological records in northern China

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Science China Earth Sciences 2019年第8期62卷 1181-1192页

作者： shiling yang Xinxin DONG Jule XIAO Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Institutions of Earth Science Chinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China University of Chinese Academy of Sciences Beijing 100049China Bureau of General Affairs Chinese Academy of SciencesBeijing 100864China

The impact of global warming on the climate of northern China has been investigated intensively, and the behavior of the East Asian monsoon during previous intervals of climatic warming may provide insight into future changes. In this study, we use paleovegetation records from loess and lake sediments in the marginal zone of the East Asian summer monsoon(EASM) to reconstruct the EASM during the interval of warming from the Last Glacial Maximum(LGM) to the Holocene. The results show that during the LGM, desert steppe or dry steppe dominated much of northern China;in addition, the southeastern margin of the deserts east of the Helan Mountains had a distribution similar to that of the present-day, or was located slightly further south, due to the cold and dry climate caused by a strengthened East Asian winter monsoon(EAWM) and weakened EASM. During the last deglaciation, with the strengthening of the EASM and concomitant weakening of the EAWM, northern China gradually became humid. However, this trend was interrupted by abrupt cooling during the Heinrich 1(H1) and Younger Dryas(YD) events. The EASM intensified substantially during the Holocene, and the monsoon rain belt migrated at least 300 km northwestwards, which led to the substantial shrinking of the desert area in the central and eastern part of northern China, and to the large expansion of plants favored by warm and humid conditions. Paleoclimatic records from the marginal zone of the EASM all show that the EASM reached its peak in the mid-Holocene, and past global climatic warming significantly strengthened the EASM, thereby greatly improving the ecological environment in northern China. Thus, northern China is expected to become wetter as global warming continues. Finally, high resolution Holocene vegetation records are sparse compared with the numerous records on the orbital timescale, and there is a need for more studies of Holocene climatic variability on the centennial-to-decadal scale.

关键词： East Asian monsoon Last Glacial Maximum Holocene Paleovegetation Global warming

Seven million-year iron geochemistry record from a thick eolian red clay-loess sequence in Chinese Loess Plateau and the implications for paleomonsoon evolution

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Chinese Science Bulletin 2001年第4期46卷 337-341页

作者： shiling yang Zhongli Ding Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Recently, the Tertiary red clay sequence underlying Pleistocene loess has attracted much attention. The remarkable progress is the recognition that the Tertiary red clay sequence is also wind-blown in origin, thus providing a good opportunity to reconstruct long-term monsoon changes. In contrast to the loess deposits, the magnetic susceptibility and the pedogenic characteristics are almost independent of each other in the red clay, thus challenging the validity of the readily measurable magnetic susceptibility in describing the monsoon history recorded by the red clay. With the objective to address the long-term East Asia summer monsoon evolution, the free to total Fe2O3 ratios were calculated in a continuous eolian red clay-loess sequence at Lingtai, the Chinese Loess Plateau, which has a thickness of 305 m and a basal age of 7.0 Ma. The seven million-year Fe2O3 ratio record from the red clay-loess sequence indicates that (i) variations of the free to total Fe2O3 ratios of the loess can correlate

关键词： red clay-loess sequence free to total Fe2O3 ratios paleo-monsoon.

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全球变暖对水循环的影响:回顾与展望

第四纪研究 2024年第5期44卷 1079-1092页

作者：杨石岭陈祚伶黄晓芳唐自华张师豪姜文英丁仲礼中国科学院地质与地球物理研究所岩石圈演化与环境演变全国重点实验室北京100029 中国科学院大学地球与行星科学学院北京100049

20世纪70年代以来,全球气候变化引发了学术界的广泛关注。本文简要回顾了最近几十年来不同时间尺度气候变化预测的观点,总结了全球变暖可能引发的环境效应。在此基础上,梳理了新生代地质温暖期的东亚环境状况。从哲学和地质历史的角度... 详细信息

20世纪70年代以来,全球气候变化引发了学术界的广泛关注。本文简要回顾了最近几十年来不同时间尺度气候变化预测的观点,总结了全球变暖可能引发的环境效应。在此基础上,梳理了新生代地质温暖期的东亚环境状况。从哲学和地质历史的角度看气候维持不变是不可能的,未来要么在北半球太阳辐射的驱动下变冷,要么在温室气体的作用下变暖。地质记录和气候模拟结果大多显示,地质温暖期东亚夏季风雨带北进、降水增加;古增温导致水汽含量增加、热带辐合带北移和西太平洋副热带高压扩张是东亚季风降水增加的根本原因;从冰期-间冰期尺度看,全球变暖不仅对东亚地区是利大于弊,对全球大部分地区也是利大于弊;就提升未来气候变化预测和预估准确性而言,加强气候系统内部自然变率研究是当务之急。

关键词：古增温地质记录东亚夏季风大气CO_(2)浓度

Highly Thermo-Conductive Three-Dimensional Graphene Aqueous Medium

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Nano-Micro Letters 2020年第10期12卷 224-235页

作者： Zheng Bo Chongyan Ying Huachao yang Shenghao Wu Jinyuan yang Jing Kong shiling yang yanguang Zhou Jianhua Yan Kefa Cen State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringCollege of Energy EngineeringZhejiang University38 Zheda RoadHangzhou 310027People’s Republic of China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 311215People’s Republic of China Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongPeople’s Republic of China

Highly thermo-conductive aqueous medium is a crucial premise to demonstrate high-performance thermal-related *** has the diamond comparable thermal conductivity,while the intrinsic two-dimensional reality will result in strong anisotropic thermal conductivity and wrinkles or even crumples that significantly sacrifices its inherent properties in practical *** strategy to overcome this is to use three-dimensional(3D)architecture of ***,3D graphene structure with covalent-bonding nanofins(3D-GS-CBF)is proposed,which is then used as the filler to demonstrate effective aqueous *** thermal conductivity and thermal conductivity enhancement efficiency of 3D-GS-CBF(0.26 vol%)aqueous medium can be as high as 2.61 W m-1 K-1 and 1300%,respectively,around six times larger than highest value of the existed aqueous ***,3D-GS-CBF can be stable in the solution even after 6 months,addressing the instability issues of conventional graphene networks.A multiscale modeling including non-equilibrium molecular dynamics simulations and heat conduction model is applied to interpret experimental results.3D-GS-CBF aqueous medium can largely improve the solar vapor evaporation rate(by 1.5 times)that are even comparable to the interfacial heating system;meanwhile,its cooling performance is also superior to commercial coolant in thermal management applications.

关键词： Three-dimensional graphene Thermo-conductive aqueous medium Multiscale modeling Solar thermal conversion Practical thermal management

Pedogenic carbonate isotope record of vegetational evolution since late Miocene in Loess Plateau

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Chinese Science Bulletin 1999年第11期44卷 1034-1038页

作者： shiling yang Zhongli Ding Zhaoyan Gu Jimin Sun Shangfa Xiong Chinese Acad Sci Inst Geol Beijing 100029 Peoples R China

lsotopic analyses for paleovegetational evolution have been carried out on samples of the pedogenic carbonate nodules in the Red Clay-Loess sequence at Lingtai （35°N）, the Loess Plateau. Stable carbon isotopic composition indicates that （ ⅰ ） C4 plants might be present at least by7.0 Ma; （ ⅱ ） C4 plants expanded gradually between ～4.0 and ～3.2 Ma, and their biomass fraction was up to 50%; and （ ⅲ ） the biomass of C4 vegetation since ～2.0 Ma seems to have been decreased to the level （about 20%） before 4.0 Ma. C4 plant expansion at Lingtai cannot be fully understood with the 'global C4 expansion' model because it occurred much later up to 3.0 Ma than in Pakistan, which indicates that some changes in the regional climatic system may also contribute to C3/C4 shift except changes in atmospheric CO2 concentrations and temperature. The latitudinal zone for C3/C4 transition seems to move southwards slightly in East Asia, compared with the case in North America where 37°N is the ideal

关键词： pedogenic carbonate palaeovegetation shift atmospheric CO2 concentrations.

Methods and application of using detrital zircons to trace the provenance of loess

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Science China Earth Sciences 2012年第6期55卷 1837-1846页

作者： XIE Jing yang shiling DING ZhongLi Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The composition of single-grain detrital zircons is an effective provenance indicator of loess,and sheds new light on dust formation and *** we review the features of detrital zircons and their use as a provenance indicator,including internal structure,trace element,U-Pb age spectrum and Hf isotopic compositions,and present a case study from the Horqin sandy land and its surrounding *** loess samples have detrital zircon age peaks in range of 2600-2300,2100-1600,and 600-100 Ma,of which the 2600-2300 Ma zircon grains mainly have positive Hf(t) values(3.4-8.7),the 2100-1600 Ma zircon grains mainly have negative Hf(t) values(10.1-6.8),and the 600-100 Ma zircon grains have a variable Hf(t) values ranging from 21 to *** detrital zircon signatures of the loess are similar to the Horqin sandy land,but clearly different from the Chinese Loess Plateau and central-western deserts,implying that the loess is transported mainly from the Horqin sandy land in the Last Glacial *** these with neighboring tectonic units,we found that zircon populations at 2600-2300,2100-1600,and 600-100 Ma with negative Hf(t) values may come from the northeast North China Craton(NCC),and those at 600-100 Ma with positive Hf(t) values may come from the east Central Asian Orogenic Belt(CAOB).It is estimated that the two sources contribute equally to the Horqin sandy land and the surrounding loess.

关键词： loess provenance detrital zircon U-Pb age Hf isotope Horqin sandy land

深时重大生物和气候事件与全球变化:进展与挑战

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科学通报 2024年第2期69卷 268-285页

作者：沈树忠张飞飞王文倩王向东樊隽轩陈吉涛王博曹剑杨石岭张华李高军邓涛李献华陈骏南京大学地球科学与工程学院关键地球物质循环前沿科学中心内生金属成矿机制研究国家重点实验室南京210023 中国科学院南京地质古生物研究所现代古生物学与地层学国家重点实验室南京210008 中国科学院地质与地球物理研究所新生代地质与环境重点实验室北京100029 中国科学院古脊椎动物与古人类研究所脊椎动物演化与人类起源重点实验室北京100044 中国科学院地质与地球物理研究所岩石圈演化国家重点实验室北京100029

地球自5.4亿年前现代生态系统形成至今,发生了多次与碳循环扰动有关的重大气候事件.这些事件的触发机制、发展过程、环境变化及其伴随的生物响应型式为科学评估当今全球变化背景下生物多样性现状提供重要借鉴.然而,古-今生态系统变化时... 详细信息

地球自5.4亿年前现代生态系统形成至今,发生了多次与碳循环扰动有关的重大气候事件.这些事件的触发机制、发展过程、环境变化及其伴随的生物响应型式为科学评估当今全球变化背景下生物多样性现状提供重要借鉴.然而,古-今生态系统变化时间尺度大不相同,高分辨率关键环境因子(温度、CO_(2)、降雨量、海洋氧化还原条件等)在深时记录中亦难以获取,深时海陆生物多样性模式尚缺乏高分辨率记录.因此,当今全球变化与深时记录对比存在巨大鸿沟.地球5.4亿年以来大部分时间处于两极无冰的温室状态,期间伴随多次极冷和极热气候事件,但地球深时重大生物演化和气候事件的关系复杂.生物多样性在变冷的奥陶纪早期、晚古生代大冰期、晚新生代大冰期以及中-晚三叠世和白垩纪热室期均呈现稳定增加,而在奥陶纪末冰期快速降温期间和二叠纪末、三叠纪末、白垩纪末火山排气作用导致的快速升温过程中急剧下降.地质时期生物多样性对气候变化的不同响应型式表明,生物多样性变化的根本驱动因素可能不是简单的温度、大气CO_(2)浓度等环境因子的背景值高或低,而是环境因子的变化速率(环境变率).变率较小,环境相对稳定,生物有足够的时间适应环境变化,生物多样性不会丧失,甚至繁盛.反之,若环境因子变率过大,超出了生态系统的承受力,生物来不及适应,生物多样性就会显著降低,甚至引发大灭绝.已有模拟和计算表明,当今地球碳排放的速度有可能超过了地质历史时期任何一次生物大灭绝事件.因此,避免环境突变事件和生物大灭绝的再次发生成为政界、科学界和普通民众关注的焦点.打通地球多圈层界限,开展古-今地质记录、冷-热极端气候、海-陆生态系统和长-短时间尺度的综合对比研究,并通过建立适用于深时的地球系统模型,模拟重大生物和环境事件的背景与发生过程,是地球系统科学未来发展的重要方向.

关键词：深时极端气候重大生物事件环境变率全球变化地球系统模拟

A 249 kyr stack of eight loess grain size records from northern China documenting millennial-scale climate variability

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A 249 kyr stack of eight loess grain size records from north...