Temperature signal recorded in δ2H and δ13C values of wood lignin methoxyl groups from a permafrost forest in northeastern China

Yabo Wang; Xiaohong Liu; Tobias Anhäuser; Qiangqiang Lu; Xiaomin Zeng; Qiuliang Zhang; Keyi Wang; Lingnan Zhang; Yu Zhang; Frank Keppler

doi:10.1016/j.scitotenv.2020.138558

Temperature signal recorded in δ²H and δ¹³C values of wood lignin methoxyl groups from a permafrost forest in northeastern China

Sci Total Environ. 2020 Jul 20:727:138558. doi: 10.1016/j.scitotenv.2020.138558. Epub 2020 Apr 8.

Authors

Affiliations

¹ School of Geography and Tourism, Shaanxi Normal University, Xi'an 710119, China.
² School of Geography and Tourism, Shaanxi Normal University, Xi'an 710119, China; State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China. Electronic address: xhliu@snnu.edu.cn.
³ Institute of Earth Sciences, Heidelberg University, Im Neuenheimer Feld 234-236, 69120 Heidelberg, Germany; Department of Chemical and Physical Sciences, University of Toronto Mississauga, Mississauga L5L1C6, Canada.
⁴ School of Geography and Tourism, Shaanxi Normal University, Xi'an 710119, China; Xi'an Botanical Garden of Shaanxi Province (Institute of Botany of Shaanxi Province), Xi'an 710061, China.
⁵ Forest College of Inner Mongolia Agricultural University, Hohhot, Inner Mongolia 010018, China.
⁶ Institute of Earth Sciences, Heidelberg University, Im Neuenheimer Feld 234-236, 69120 Heidelberg, Germany; Heidelberg Center for the Environment HCE, Heidelberg University, D-69120 Heidelberg, Germany.

PMID: 32498208
DOI: 10.1016/j.scitotenv.2020.138558

Abstract

Stable isotopes in wood lignin methoxyl groups (δ²H_LM and δ¹³C_LM values) have been suggested as valuable complementary paleoclimate proxies. In permafrost forests, tree growth is influenced by multiple factors, however temperature appears to have the strongest impact on tree growth and, therefore, on carbon cycling. To test whether δ²H_LM and δ¹³C_LM values of trees from permafrost regions might record climate parameters, two dominant tree species (Larix gmelinii, larch, and Pinus sylvestris var. mongolica, pine) collected from a permafrost forest in China's Greater Hinggan Mountains, were investigated. The two tree species larch and pine covered time spans of 1940 to 2013 and 1870 to 2013, respectively. Results showed significant correlations of pine and larch δ²H_LM values and larch δ¹³C_LM values with temperatures and in particular with the mean temperature of the growing season from April to August. However, only weak correlations of δ²H_LM and δ¹³C_LM values with moisture conditions, such as precipitation amount and relative humidity were observed. In addition, species specificity in the climate response was most obvious for δ¹³C_LM values. Compared to a temperature reconstruction based on tree ring width, pine δ²H_LM-based reconstruction showed strongest spatial correlations with regional temperature. Therefore, δ²H_LM values might be a promising proxy to reconstruct growing-season temperatures in permafrost regions.

Keywords: Larix gmelinii; Pinus sylvestris var. mongolica; Temperature reconstruction; Tree rings; δ(2)H(LM) and δ(13)C(LM).

MeSH terms

China
Forests
Lignin
Permafrost*
Temperature
Trees
Wood

Substances

Lignin