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DOI	10.1007/s11430-016-9055-4
	Altitudinal effect of soil n-alkane delta D values on the eastern Tibetan Plateau and their increasing isotopic fractionation with altitude
	Bai Yan; Chen ChiHao; Fang XiaoMin; Liu XiaoMing; Guo HaiChao
通讯作者	Bai, Y (通讯作者)
发表日期	2017
ISSN	1674-7313
EISSN	1869-1897
起始页码	1664
结束页码	1673
卷号	60 期号:9
英文摘要	Stable isotope paleoaltimetry has provided unprecedented insights into the topographic histories of many of the world's highest mountain ranges. However, on the Tibetan Plateau (TP), stable isotopes from paleosols generally yield much higher paleoaltitudes than those based on fossils. It is therefore essential when attempting to interpret accurately this region's paleoaltitudes that the empirical calibrations of local stable isotopes and the relations between them are established. Additionally, it is vital that careful estimations be made when estimate how different isotopes sourced from different areas may have been influenced by different controls. We present here 29 hydrogen isotopic values for leaf wax-derived n-alkanes (i.e., D-delta(wax) values, and abundance-weighted average delta D values of C-29 and C-31) in surface soils, as well as the delta D values of soil water (delta D-sw) samples (totaling 22) from Mount Longmen (LM), on the eastern TP (altitude similar to 0.8-4.0 km above sea level (asl), a region climatically affected by the East Asian Monsoon (EAM). We compared our results with published data from Mount Gongga (GG). In addition, 47 river water samples, 55 spring water samples, and the daily and monthly summer precipitation records (from May to October, 2015) from two precipitation observation stations were collected along the GG transect for delta D analysis. LM soil D-delta(wax) values showed regional differences and responded strongly to altitude, varying fromaEuro'160aEuro degrees toaEuro'219aEuro degrees, with an altitudinal lapse rate (ALR) ofaEuro'18aEuro degrees km(aEuro'1) (R (2)=0.83; p < 0.0001; n=29). These D-delta(wax) values appeared more enriched than those from the GG transect by similar to 40aEuro degrees. We found that both the climate and moisture sources led to the differences observed in soil D-delta(wax) values between the LM and GG transects. We found that, as a general rule, epsilon (wax/rw), epsilon (wax/p) and epsilon (wax/sw) values (i.e., the isotopic fractionation of D-delta(wax) corresponding to delta D-rw, delta D-p and delta D-sw) increased with increasing altitude along both the LM and GG transects (up to 34aEuro degrees and 50aEuro degrees, respectively). Basing its research on a comparative study of D-delta(wax), delta D-p, delta D-rw(delta D-springw) and delta D-sw, this paper discusses the effects of moisture recycling, glacier-fed meltwater, relative humidity (RH), evapotranspiration (ET), vegetation cover, latitude, topography and/or other factors on epsilon (wax/p) values. Clearly, if epsilon (wax-p) values at higher altitudes are calculated using smaller epsilon (wax-p) values from lower altitudes, the calculated paleowater delta D-p values are going to be more depleted than the actual delta D values, and any paleoaltitude would therefore be overestimated.
关键词	STABLE-ISOTOPE WATER ISOTOPES METEORIC WATER LUNPOLA BASIN LATE MIOCENE PRECIPITATION CHINA PALEOELEVATION ELEVATION GRADIENTS
英文关键词	Hydrogen isotope values for leaf wax-derived n-alkanes; Aparent fractionation factor; Surface water evaporation; Local water vapor recycling; Paleoaltitudinal reconstruction; Eastern Tibetan Plateau
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000409376600009
来源期刊	SCIENCE CHINA-EARTH SCIENCES
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/258940
推荐引用方式 GB/T 7714	Bai Yan,Chen ChiHao,Fang XiaoMin,et al. Altitudinal effect of soil n-alkane delta D values on the eastern Tibetan Plateau and their increasing isotopic fractionation with altitude[J]. 中国科学院青藏高原研究所,2017,60(9).
APA	Bai Yan,Chen ChiHao,Fang XiaoMin,Liu XiaoMing,&Guo HaiChao.(2017).Altitudinal effect of soil n-alkane delta D values on the eastern Tibetan Plateau and their increasing isotopic fractionation with altitude.SCIENCE CHINA-EARTH SCIENCES,60(9).
MLA	Bai Yan,et al."Altitudinal effect of soil n-alkane delta D values on the eastern Tibetan Plateau and their increasing isotopic fractionation with altitude".SCIENCE CHINA-EARTH SCIENCES 60.9(2017).