Tree-ring cellulose oxygen isotopes indicate atmospheric aridity in the western Kunlun Mountains. (April 2022)

• Record Type: Journal Article
• Authors: Feng, Xiaoyu; Huang, Ru; Zhu, Haifeng; Liang, Eryuan; Bräuning, Achim; Zhong, Linhao; Gong, Zhaohui; Zhang, Peng; Asad, Fayaz; Zhu, Xiaolong; Grießinger, Jussi
• Is Part Of: Ecological indicators. Volume 137(2022)
• Publication Date: 2022-04
• Subjects: Atmospheric aridity -- Tree-ring cellulose δ18O -- Vapor pressure deficit -- Frequency-dependency -- Western Kunlun Mountains; Environmental monitoring -- Periodicals; Environmental management -- Periodicals; Environmental impact analysis -- Periodicals; Environmental risk assessment -- Periodicals; Sustainable development -- Periodicals; 333.71405
• DOI: 10.1016/j.ecolind.2022.108776
• Languages: English
• ISSNs: 1470-160X

Abstract

Graphical abstract: Summary for correlations of tree-ring cellulose oxygen isotopes from the western Kunlun Mountains with climates for the raw data (left) and 5-year high-frequency data (right). The key finding is that δ 18 OTRC is indicative of atmospheric aridity (VPD) at high-frequency interannual variations (right, 5-year high-frequency data), while such indicative ability disappears for longer timescales (Left, Raw data). Highlights: A δ 18 OTRC record from 1951 to 2015 for the western Kunlun Mountains was generated. δ 18 OTRC indicate May to August VPD variability at timescales <5 years. Frequency-dependency can highly influence the climatic interpretation of δ 18 OTRC . Abstract: As an important indicator of atmospheric aridity, the vapor pressure deficit (VPD) is being paid increasing attention in global change researches during recent decades. However, available proxy data with the capability to represent VPD is still scarce in the globe. Herein we demonstrated a "hidden" frequency-dependent indication of tree-ring cellulose oxygen isotope (δ 18 OTRC ) to atmospheric aridity in the western Kunlun Mountains, Central Asia. In applying correlation and partial correlation analysis, frequency-dependent climatic drivers triggering the δ 18 OTRC values were detected. For the raw data with inter-decadal variability, δ 18 OTRC variations mainly indicated May–August precipitation (Local: r = –0.59, p < 0.001; Moisture source: r = –0.53, p < 0.001), evapotranspiration (ET) (Local: r = –0.57, p < 0.001; Moisture source: r = –0.51, p < 0.001). After a 5-year high-pass filter, the δ 18 OTRC series revealed highly significant correlation with May–August VPD (Local: r = 0.82, p < 0.001; Moisture source: r = 0.80, p < 0.001). The partial correlation further confirmed the strong linkages with high-frequency VPD when the impact of any additional eco-climatological variable (precipitation, temperature, ET, soil moisture 0–40 cm) was excluded. In contrast, if the effect of May–August VPD was excluded, relationships between δ 18 OTRC and other variables turned insignificant. Collectively, it was concluded that δ 18 OTRC from the western Kunlun Mountains may indicate VPD at timescales < 5 years. Our results suggest that frequency-dependent climatic significances should be considered when interpreting multi-process determined δ 18 OTRC as a climate-proxy.