气候变化领域集成服务门户(CCPortal): Climate-induced speleothem radiocarbon variability on Socotra Island from the Last Glacial Maximum to the Younger Dryas

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DOI	10.5194/cp-16-409-2020
	Climate-induced speleothem radiocarbon variability on Socotra Island from the Last Glacial Maximum to the Younger Dryas
	Therre S.; Fohlmeister J.; Fleitmann D.; Matter A.; Burns S.J.; Arps J.; Schröder-Ritzrau A.; Friedrich R.; Frank N.
发表日期	2020
ISSN	18149324
起始页码	409
结束页码	421
卷号	16 期号:1
英文摘要	In this study, the dead carbon fraction (DCF) variations in stalagmite M1-5 from Socotra Island in the western Arabian Sea were investigated through a new set of high-precision U-series and radiocarbon (14C) dates. The data reveal an extreme case of very high and also climate-dependent DCF. For M1-5, an average DCF of 56.2±3.4% is observed between 27 and 18kyrBP. Such high DCF values indicate a high influence of aged soil organic matter (SOM) and nearly completely closed-system carbonate dissolution conditions. Towards the end of the last glacial period, decreasing Mg/Ca ratios suggest an increase in precipitation which caused a marked change in the soil carbon cycling as indicated by sharply decreasing DCF. This is in contrast to the relation of soil infiltration and DCF as seen in stalagmites from temperate zones. For Socotra Island, which is influenced by the East African-Indian monsoon, we propose that more humid conditions and enhanced net infiltration after the Last Glacial Maximum (LGM) led to dense vegetation and thus lowered the DCF by increasing 14CO2 input into the soil zone. At the onset of the Younger Dryas (YD) a sudden change in DCF towards much higher, and extremely variable, values is observed. Our study highlights the dramatic variability of soil carbon cycling processes and vegetation feedback on Socotra Island manifested in stalagmite DCF on both long-term trends and sub-centennial timescales, thus providing evidence for climate influence on stalagmite radiocarbon. This is of particular relevance for speleothem studies that aim to reconstruct past atmospheric 14C (e.g., for the purposes of 14C calibration), as these would rely on largely climate-independent soil carbon cycling above the cave. © 2020 Copernicus GmbH. All rights reserved.
语种	英语
scopus关键词	dissolution; infiltration; Last Glacial Maximum; paleoclimate; radiocarbon dating; soil organic matter; speleothem; stalagmite; Younger Dryas; Arabian Sea; Arkhabil Suqutra; Indian Ocean; Yemen
来源期刊	Climate of the Past
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/146738
作者单位	Institute of Environmental Physics, Heidelberg University, Heidelberg, Germany; Potsdam Institute for Climate Impact Research, Potsdam, Germany; GFZ German Research Centre for Geosciences, Section Climate Dynamics and Landscape Development, Potsdam, Germany; Department of Environmental Sciences, University of Basel, Basel, Switzerland; Institute of Geological Sciences, University of Bern, Bern, Switzerland; Department of Geosciences, University of Massachusetts, Amherst, United States; Curt-Engelhorn-Centre Archaeometry GGmbH, Mannheim, Germany
推荐引用方式 GB/T 7714	Therre S.,Fohlmeister J.,Fleitmann D.,et al. Climate-induced speleothem radiocarbon variability on Socotra Island from the Last Glacial Maximum to the Younger Dryas[J],2020,16(1).
APA	Therre S..,Fohlmeister J..,Fleitmann D..,Matter A..,Burns S.J..,...&Frank N..(2020).Climate-induced speleothem radiocarbon variability on Socotra Island from the Last Glacial Maximum to the Younger Dryas.Climate of the Past,16(1).
MLA	Therre S.,et al."Climate-induced speleothem radiocarbon variability on Socotra Island from the Last Glacial Maximum to the Younger Dryas".Climate of the Past 16.1(2020).