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Title: Soil volatile organic compound emissions in response to soil warming and nitrogen deposition
Biogenic volatile organic compounds (VOCs) play crucial roles in ecosystems at multiple scales, ranging from mediating soil microbial interactions to contributing to atmospheric chemistry. However, soil VOCs and how they respond to environmental change remains understudied. We aimed to assess how 2 abiotic global change drivers, soil warming and simulated nitrogen (N) deposition, impact soil VOC emissions over time in a temperate forest. We characterized the effect of warming, N deposition, and their interaction on the composition and emissions of soil VOCs during the growing season of 2 consecutive years. We found that chronic warming and N deposition enhanced total VOC emissions at certain times of the year (as high as 332.78 µg m–2 h–1), but that overall VOC composition was not strongly affected by these global change treatments. However, certain compounds, particularly sesquiterpenoids and alkanes, were sensitive to these treatments, with their emissions increasing under both chronic warming and N deposition. Moreover, specific signature VOCs—α-pinene, β-thujone, β-caryophyllene, and 2,4-dimethylheptane—were consistently found under chronic warming and N deposition. This suggests that emissions of specific VOC classes/compounds may increase under global change.  more » « less
Award ID(s):
1832210
PAR ID:
10397129
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Elementa: Science of the Anthropocene
Volume:
10
Issue:
1
ISSN:
2325-1026
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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