气候变化领域集成服务门户(CCPortal): Organic matter geochemical signatures of sediments of Lake Ngoring (Qinghai-Tibetan Plateau): A record of environmental and climatic changes in the source area of the Yellow River for the last 1500 years

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DOI	10.1016/j.palaeo.2020.109729
	Organic matter geochemical signatures of sediments of Lake Ngoring (Qinghai-Tibetan Plateau): A record of environmental and climatic changes in the source area of the Yellow River for the last 1500 years
	Pu Y.; Werne J.P.; Meyers P.A.; Zhang H.
发表日期	2020
ISSN	0031-0182
卷号	551
英文摘要	The climate history of the source area of the Yellow River (SAYR) is important to understanding the pacing and processes of climate evolution on the northeastern Qinghai-Tibetan Plateau (QTP). To date, results of research in this alpine region are limited. Herein, we provide a first lacustrine record from the largest freshwater lake on the QTP that archives climatic and environmental variations in the SAYR for the last 1500 yr. The bulk organic carbon and nitrogen isotopic compositions (δ13Corg and δ15Ntot) are combined with atomic carbon/nitrogen (C/N) ratios to indicate that the sedimentary organic matter in Lake Ngoring originates from autochthonous algae and that the terrestrial input is minor. Comparison of the record of organic carbon isotope values with published records of ice accumulation rate (IAR) of Dunde and Guliya glaciers from the northern QTP, the total solar irradiance (TSI), δ18O variations in the Greenland ice core and biologically sensitive indicators (C37:4 alkenone, crenarchaeol and bGDGT concentrations) from Lake Qinghai indicate that variations in the δ13Corg values in Lake Ngoring sediments reflect lake level fluctuations that are associated with variations in the amount of precipitation and glacier meltwater on the SAYR. High lake level phases indicated by positive shifts of δ13Corg values correspond to higher values of the North Atlantic Oscillation Index (NAOI) and lower values of the Southern Oscillation Index (SOIpr). This relation suggests that the hydrologic history in the SAYR is linked to changes in the Indian monsoon and the Westerlies and that both air masses delivered more moisture to the SAYR during high TSI stages. In contrast, variations in the δ15Ntot values resemble the multiple paleoclimate proxy records obtained from ice cores, peat sequences, lake sediments, and integrated paleo-records from other QTP sites, suggesting that the δ15Ntot values archived in Lake Ngoring sediments provide a history of past lake-water temperature variations that is consistent with the variation history of the temperature-dependent parameters from regional paleo-climatic studies. Global climatic events including the Dark Ages Cold Period, the Medieval Climate Anomaly, the Little Ice Age and Modern Warming in 20th century could be clearly observed in the δ15Ntot variations. In general, the δ13Corg and δ15Ntot values in Lake Ngoring sediments appear to be useful indicators for paleo-environment and paleo-climate reconstructions in alpine oligotrophic freshwater lakes such as this one. © 2020 Elsevier B.V.
英文关键词	Bulk organic matter; Climatic events; Indian monsoon; Lake level; Lake-water temperatures; Westerlies
语种	英语
scopus关键词	accumulation rate; carbon isotope; GRIP; ice core; lake level; Little Ice Age; Medieval Warm Period; meltwater; North Atlantic Oscillation; organic carbon; organic matter; paleoclimate; Southern Oscillation; Arctic; China; Greenland; Qinghai Lake; Qinghai-Xizang Plateau; Yellow River; algae
来源期刊	Palaeogeography, Palaeoclimatology, Palaeoecology
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/150479
作者单位	School of Geographical Sciences, Nanjing University of Information Science & Technology, Nanjing, 210044, China; Department of Geology and Environmental Science, University of Pittsburgh, Pittsburgh, PA 15260, United States; Department of Earth and Environmental Sciences, The University of Michigan, Ann Arbor, MI 48109, United States; School of Ecology and Environmental Science, Yunnan University, Kunming, 650091, China
推荐引用方式 GB/T 7714	Pu Y.,Werne J.P.,Meyers P.A.,et al. Organic matter geochemical signatures of sediments of Lake Ngoring (Qinghai-Tibetan Plateau): A record of environmental and climatic changes in the source area of the Yellow River for the last 1500 years[J],2020,551.
APA	Pu Y.,Werne J.P.,Meyers P.A.,&Zhang H..(2020).Organic matter geochemical signatures of sediments of Lake Ngoring (Qinghai-Tibetan Plateau): A record of environmental and climatic changes in the source area of the Yellow River for the last 1500 years.Palaeogeography, Palaeoclimatology, Palaeoecology,551.
MLA	Pu Y.,et al."Organic matter geochemical signatures of sediments of Lake Ngoring (Qinghai-Tibetan Plateau): A record of environmental and climatic changes in the source area of the Yellow River for the last 1500 years".Palaeogeography, Palaeoclimatology, Palaeoecology 551(2020).