干旱区生态环境知识资源中心(Arid): Vegetation effects on temperature calibrations of branched glycerol dialkyl glycerol tetraether (brGDGTs) in soils

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DOI	10.1016/j.orggeochem.2018.10.010
	Vegetation effects on temperature calibrations of branched glycerol dialkyl glycerol tetraether (brGDGTs) in soils
	Liang, Jie 1,2,3; Russell, James M.3; Xie, Haichao 3,4; Lupien, Rachel L.3; Si, Guicai 1,5; Wang, Jian 1,6; Hou, Juzhi 1; Zhang, Gengxin 1
通讯作者	Zhang, Gengxin
来源期刊	ORGANIC GEOCHEMISTRY
ISSN	0146-6380
EISSN	1873-5290
出版年	2019
卷号	127 页码:1-11
英文摘要	Distributions of branched glycerol dialkyl glycerol tetraether (brGDGT) lipids are sensitive to environmental parameters, which enables their use in paleoenvironmental studies. In particular, the degree of methylation of brGDGTs (MBT and MBT') and the cyclization ratio of brGDGTs (CBT) are often used to estimate changes in temperature in paleoclimate studies. Application of these proxies requires reliable and precise calibrations to temperature. However, available calibrations of brGDGT proxies to temperature have large calibration errors in arid areas which suggests that other environmental variables influence brGDGT distributions in these areas. Here we analyze brGDGT distributions in soils from the Tibetan Plateau, an arid/semi-arid region with gradients in vegetation cover (forest, grassland, and desert) to examine: (1) the applicability of MBT'/CBT calibrations to reconstruct mean annual air temperature (MAAT); and (2) the effects of vegetation cover on temperature calibrations. We show that temperatures reconstructed using the global soil MBT'/CBT calibrations are warmer than instrumentally observed temperature, and that the calibrations are significantly influenced by the presence or absence of vegetation. Excluding sample sites without vegetation (bare soil) from temperature calibrations substantially improves the correlation between observed and reconstructed temperatures. Within the vegetated soils, we reanalyzed published global soil calibration datasets, including results of analyses that either did or did not separate 5- and 6-methyl brGDGT isomers, and find that the correlation between MBT'(5Me) and MBT' and temperature varies for different vegetation types (grass and forest) and that the error of temperature calibrations is reduced if calibrations are separated by the type of vegetative cover (grass or forest). We test these new calibrations in sequences from the Lantian and Mangshan loess of the Chinese Loess Plateau and find that reconstructed temperatures from both modern and Last Glacial Maximum sediments are more consistent with other reconstructions and climate model simulations when vegetation-specific calibrations are applied to the brGDGT data. The results indicate that changes in vegetation should be taken into consideration when applying brGDGT proxies to reconstruct past changes in climate. (C) 2018 Published by Elsevier Ltd.
英文关键词	Vegetation cover Vegetation type MBT ' CBT MBT '(5Me ) CBT5Me
类型	Article
语种	英语
国家	Peoples R China ; USA
收录类别	SCI-E
WOS记录号	WOS:000454881700001
WOS关键词	LOESS-PALEOSOL SEQUENCE ; ISO-DIABOLIC ACID ; MEMBRANE-LIPIDS ; MICROBIAL COMMUNITY ; SURFACE SOILS ; EAST-ASIA ; DISTRIBUTIONS ; GDGTS ; PROXIES ; PH
WOS类目	Geochemistry & Geophysics
WOS研究方向	Geochemistry & Geophysics
来源机构	兰州大学 ; 中国科学院青藏高原研究所 ; 中国科学院地质与地球物理研究所
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/217825
作者单位	1.Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Alpine Ecol, Beijing 100101, Peoples R China; 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China; 3.Brown Univ, Dept Earth Environm & Planetary Sci, Providence, RI 02912 USA; 4.Lanzhou Univ, Coll Earth & Environm Sci, MOE Key Lab West Chinas Environm Syst, Lanzhou 730000, Gansu, Peoples R China; 5.Chinese Acad Sci, Inst Geol & Geophys, Lanzhou Ctr Oil & Gas Resources, Lanzhou 730000, Gansu, Peoples R China; 6.China West Normal Univ, Land & Resource Coll, Nanchong 637002, Sichuan, Peoples R China
推荐引用方式 GB/T 7714	Liang, Jie,Russell, James M.,Xie, Haichao,et al. Vegetation effects on temperature calibrations of branched glycerol dialkyl glycerol tetraether (brGDGTs) in soils[J]. 兰州大学, 中国科学院青藏高原研究所, 中国科学院地质与地球物理研究所,2019,127:1-11.
APA	Liang, Jie.,Russell, James M..,Xie, Haichao.,Lupien, Rachel L..,Si, Guicai.,...&Zhang, Gengxin.(2019).Vegetation effects on temperature calibrations of branched glycerol dialkyl glycerol tetraether (brGDGTs) in soils.ORGANIC GEOCHEMISTRY,127,1-11.
MLA	Liang, Jie,et al."Vegetation effects on temperature calibrations of branched glycerol dialkyl glycerol tetraether (brGDGTs) in soils".ORGANIC GEOCHEMISTRY 127(2019):1-11.