| Title | Disentangling temperature effects on leaf wax n-alkane traits and carbon isotopic composition from phylogeny and precipitation |
| Authors | Wang, Jia Xu, Yunping Zhou, Liping Shi, Minrui Axia, Ergu Jia, Yufu Chen, Zixun Li, Jiazhu Wang, Guoan |
| Affiliation | China Agr Univ, Beijing Key Lab Farmland Soil Pollut Prevent & Re, Coll Resources & Environm Sci, Beijing 100193, Peoples R China. Peking Univ, Coll Urban & Environm Sci, MOE Key Lab Earth Surface Proc, Beijing 100871, Peoples R China. Chinese Acad Forestry, Inst Desertificat Studies, Beijing 100091, Peoples R China. Shanghai Ocean Univ, Hadal Sci & Technol Res Ctr HAST, Coll Marine Sci, Shanghai 201306, Peoples R China. |
| Keywords | Temperature effect Leaf wax n-alkanes Average chain length Carbon isotopic composition 400 mm isohyet Paleotemperature reconstruction COMPOUND-SPECIFIC DELTA-C-13 SEDIMENTARY ORGANIC-MATTER EOCENE THERMAL MAXIMUM PALEOVEGETATION RECONSTRUCTION TERRESTRIAL PLANTS HYDROGEN ISOTOPES BIOMARKER RECORD CUTICULAR WAX CHINESE LOESS GAS-EXCHANGE |
| Issue Date | 2018 |
| Publisher | ORGANIC GEOCHEMISTRY |
| Citation | ORGANIC GEOCHEMISTRY. 2018, 126, 13-22. |
| Abstract | Leaf wax n-alkanes are terrestrial plant biomarkers that have characteristics that are widely employed as proxies for climatic conditions. Understanding the relationship between different environmental factors to the amounts and types of leaf wax n-alkanes in modern plants is crucial for the application of these proxies to paleoenvironmental reconstructions. However, the effects of climate conditions on plant wax characteristics remain complicated due to the interactions among temperature, precipitation and phylogeny. To evaluate the effect of temperature with minimized interfering factors, we collected 106 Artemisia plants across a 15 degrees C mean annual temperature gradient along the 400 mm isohyet in China. Both total n-alkane concentration (Sigma alk) and carbon preference index (CPI) varied greatly but did not correlate with temperature. Average chain length (ACL) increased with temperature, especially summer temperature (T-JJA , June-August), indicating that ACL could be used as proxy for temperature. The stable carbon isotope compositions of n-C-27 , n-C-29 and n-C-31 were very similar in each plant (-38.2 parts per thousand, to -30.0 parts per thousand, -39.0 parts per thousand, to -30.2 parts per thousand, -38.7 parts per thousand, to -30.5 parts per thousand, respectively), which reflects a similar biosynthetic process for all three n-alkane homologues of Artemisia. There was a positive relationship between delta(13) C of bulk leaf tissues (delta C-13(b)ulk ) and of n-alkanes (delta C-13(alk)), and the average offset of delta C-13(29) relative to delta C-13(bulk) (epsilon c29/bulk) was -7.1 parts per thousand. Increasing trends in both delta C-13(bulk) and delta C-13(29) were found with temperature. However, correlation of delta C-13(b)ulk with temperature (R-2 = 18%) was much weaker than that of delta C-13(29) with temperature (R-2 = 60%). Therefore, delta C-13(29) appears to be a better proxy of paleotemperature than delta C-13(b)ulk . (C) 2018 Elsevier Ltd. All rights reserved. |
| URI | http://hdl.handle.net/20.500.11897/570842 |
| ISSN | 0146-6380 |
| DOI | 10.1016/j.orggeochem.2018.10.008 |
| Indexed | SCI(E) |
| Appears in Collections: | 城市与环境学院 地表过程分析与模拟教育部重点实验室 |
