| Hydrogen isotope ratios of terrestrial leaf wax n-alkanes from the Tibetan Plateau: Controls on apparent enrichment factors, effect of vapor sources and implication for altimetry | |
| Zhang, XL (Zhang, Xiaolong)1,2; Xu, BQ (Xu, Baiqing)1,3; Gunther, F (Guenther, Franziska)4,5; Mugler, I (Muegler, Ines)4,6; Lange, M (Lange, Markus)4; Zhao, HB (Zhao, Huabiao)1,3; Li, JL (Li, Jiule)1; Gleixner, G (Gleixner, Gerd)4; Gleixner, G | |
| Source Publication | GEOCHIMICA ET COSMOCHIMICA ACTA
 |
| 2017 | |
| Volume | 211Issue:0Pages:10-27 |
| DOI | 10.1016/j.gca.2017.04.035 |
| Abstract | Empirical evidence suggested that the altitudinal dependence of hydrogen isotope ratios of leaf wax n-alkanes (dDwax) can be used to estimate paleoaltitudinal changes. However, the application of delta D-wax-based paleoaltimetry remains difficult, as the impacts of evaporative, transpirative and biosynthetic processes on hydrogen isotope fractionations in changing environments and the influence of likely changing water vapor sources are not well explored. For this study, we sampled stream waters, soils and plant leaves along two transects spanning large gradients of altitude, precipitation amount, vapor source, temperature and vegetation type on the Tibetan Plateau (TP). delta D values of stream water (as an approximation for delta D-p), soil water (delta D-sw) and plant leaf water (delta D-lw) as well as leaf wax n-alkanes were measured in order to quantify isotopic fractionations in the formation of leaf waxes. Most interestingly, we found a strong negative correlation between the evapotranspirative enrichment of leaf water against precipitation (epsilon(lw-p)), which combines the effects of soil evaporation and leaf transpiration, and the biosynthetic hydrogen isotope fractionation (epsilon(wax-lw)), which describes isotopic enrichment between leaf wax and leaf water. The relationship yields a steady apparent isotopic enrichment factor (epsilon(wax-p)) between leaf wax and precipitation, which is independent from climatic parameters and has an average value of -107 +/- 26% for grasses (monocotyledons) and -77 +/- 22% for trees (dicotyledons). Since the terrestrial n-alkanes, especially n-C27 and n-C29, in sediments are derived from trees and grasses, the likely change of the vegetation type in the uplift of mountains can change the isotopic estimates by about +/- 30%, which corresponds to an altitudinal change of +/- 1600 m. We, therefore, suggest that hydrogen isotope ratio of sedimentary n-C-31 alkane, which is mainly derived from grasses might be better proxies to reconstruct paleoaltitudes. Our large dataset of delta D-wax from trees and grasses that aimed to mirror the variability of environmental factors over geological time frames showed the lapse rates were significant, but much smaller than in previous studies. Most importantly our result demonstrated that the lapse rate significantly differed for both transects (p = 0.0068), i. e. 0.87 +/- 0.71%/100 m (R-2 = 0.28, p = 0.2841, n = 6) and 2.28 +/- 0.82%/100 m (R-2 = 0.34, p = 0.0135, n = 17) for Indian monsoon and Westerly dominated areas, respectively. This suggests that different moisture sources might strongly affected the observed lapse rates. In consequences altitude reconstructions are strongly complicated in areas with likely changing air masses like the Tibetan Plateau. (C) 2017 Elsevier Ltd. All rights reserved. |
| Subject Area | 自然地理学 |
| WOS ID | WOS:000405786800002 |
| Language | 英语 |
| Indexed By | SCI |
| Keyword | Delta-d Values Western Central-africa Stable-isotopes Organic-matter D/h Ratios Plants Implications Lipid Biosynthesis Surrounding Area Aquatic Plants Central Andes |
| WOS Research Area | Geochemistry & Geophysics |
| WOS Subject | Geochemistry & Geophysics ; Geochemistry & Geophysics |
| Cooperation Status | 国际 |
| Subtype | Article |
| Citation statistics | |
| Document Type | 期刊论文 |
| Identifier | http://ir.itpcas.ac.cn/handle/131C11/8005 |
| Collection | 图书馆 |
| Corresponding Author | Gleixner, G |
| Affiliation | 1.Chinese Acad Sci, Inst Tibetan Plateau Res, Key Lab Tibetan Environm Changes & Land Surface P, Beijing 100101, Peoples R China. 2.Univ Chinese Acad Sci, Beijing 100049, Peoples R China. 3.Chinese Acad Sci, CAS Ctr Excellence Tibetan Plateau Earth Sci, Beijing 100101, Peoples R China. 4.Max Planck Inst Biogeochem, POB 100164, D-07701 Jena, Germany. 5.Leibniz Ctr Trop Marine Res, Fahrenheitstr 6, D-28359 Bremen, Germany. 6.Univ Hamburg, Mittelweg 177, D-20148 Hamburg, Germany. |
| Recommended Citation GB/T 7714 | Zhang, XL ,Xu, BQ ,Gunther, F ,et al. Hydrogen isotope ratios of terrestrial leaf wax n-alkanes from the Tibetan Plateau: Controls on apparent enrichment factors, effect of vapor sources and implication for altimetry[J]. GEOCHIMICA ET COSMOCHIMICA ACTA,2017,211(0):10-27. |
| APA | Zhang, XL .,Xu, BQ .,Gunther, F .,Mugler, I .,Lange, M .,...&Gleixner, G.(2017).Hydrogen isotope ratios of terrestrial leaf wax n-alkanes from the Tibetan Plateau: Controls on apparent enrichment factors, effect of vapor sources and implication for altimetry.GEOCHIMICA ET COSMOCHIMICA ACTA,211(0),10-27. |
| MLA | Zhang, XL ,et al."Hydrogen isotope ratios of terrestrial leaf wax n-alkanes from the Tibetan Plateau: Controls on apparent enrichment factors, effect of vapor sources and implication for altimetry".GEOCHIMICA ET COSMOCHIMICA ACTA 211.0(2017):10-27. |
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| File Name/Size | DocType | Version | Access | License | ||
| V.211 10-27 2017.pdf（3971KB） | 期刊论文 | 作者接受稿 | 开放获取 | CC BY-NC-SA | View Application Full Text | |
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