气候变化领域集成服务门户(CCPortal): Mid-Holocene moisture maximum revealed by pH changes derived from branched tetraethers in loess deposits of the northeastern Tibetan Plateau

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DOI	10.1016/j.palaeo.2019.01.034
	Mid-Holocene moisture maximum revealed by pH changes derived from branched tetraethers in loess deposits of the northeastern Tibetan Plateau
	Duan Y.; Sun Q.; Werne J.P.; Zhao H.; Zhang D.; Zhang N.; Liu J.; Wu D.; Chen F.
发表日期	2019
ISSN	0031-0182
起始页码	138
结束页码	149
卷号	520
英文摘要	The patterns of Holocene moisture variability inferred from different proxies remain controversial in the northeastern Tibetan Plateau (NETP), which impedes our understanding of the behavior and dynamics of the East Asian Summer Monsoon (EASM). Here we present two pH records spanning the last ~12 kyr from well-dated loess-paleosol sections (YWY14 and SHD09) from the NETP. Based on the modified cyclization ratio index (CBT′) of the branched glycerol dialkyl glycerol tetraethers (brGDGTs) and regional CBT′-pH empirical relationship, the reconstructed pH values from topmost samples are consistent with the instrumental pH values of the surrounding surface soil. Our results illustrate generally similar pH trends from two loess sections characterized by alkaline conditions from 12.0 to 8.5 cal kyr BP, neutral or acidic during the mid-Holocene and alkaline conditions again during the late Holocene. The intervals of lowest CBT′-derived pH values during the mid-Holocene in our records correlate with those of highest tree pollen percentage from adjacent lake sediments and the regionally weakest aeolian activity from records of paleosol development synthesized from the Chinese Loess Plateau (CLP) in northern China, suggesting a moisture maximum during that period. Taken together, we conclude that CBT′-derived pH variability can be potentially used as an indicator of EASM evolution and the wettest climate occurred during the mid-Holocene in the NETP. The changes in summer precipitation during the Holocene on the NETP can be attributed to the interaction between the mid-latitude westerlies and the EASM circulation. © 2019 Elsevier B.V.
英文关键词	CBT′; East Asian summer monsoon; Westerlies; Wettest climate
语种	英语
scopus关键词	alkalinity; eolian process; Holocene; lacustrine deposit; loess; paleosol; pH; pollen; precipitation (climatology); summer; westerly; China; Far East; Loess Plateau; Qinghai-Xizang Plateau
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/151028
作者单位	College of Earth and Environmental Sciences, MOE Key Laboratory of Western China's Environmental System, Lanzhou University, Lanzhou, 730000, China; National Research Center of Geoanalysis, Beijing, 100037, China; Department of Geology and Environmental Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States; Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences, Institute of Tibetan Plateau Reseacrh, CAS, Beijing, 100101, China
推荐引用方式 GB/T 7714	Duan Y.,Sun Q.,Werne J.P.,et al. Mid-Holocene moisture maximum revealed by pH changes derived from branched tetraethers in loess deposits of the northeastern Tibetan Plateau[J],2019,520.
APA	Duan Y..,Sun Q..,Werne J.P..,Zhao H..,Zhang D..,...&Chen F..(2019).Mid-Holocene moisture maximum revealed by pH changes derived from branched tetraethers in loess deposits of the northeastern Tibetan Plateau.Palaeogeography, Palaeoclimatology, Palaeoecology,520.
MLA	Duan Y.,et al."Mid-Holocene moisture maximum revealed by pH changes derived from branched tetraethers in loess deposits of the northeastern Tibetan Plateau".Palaeogeography, Palaeoclimatology, Palaeoecology 520(2019).