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Title: Arctic soil methane sink increases with drier conditions and higher ecosystem respiration

Arctic wetlands are known methane (CH4) emitters but recent studies suggest that the Arctic CH4sink strength may be underestimated. Here we explore the capacity of well-drained Arctic soils to consume atmospheric CH4using >40,000 hourly flux observations and spatially distributed flux measurements from 4 sites and 14 surface types. While consumption of atmospheric CH4occurred at all sites at rates of 0.092 ± 0.011 mgCH4 m−2 h−1(mean ± s.e.), CH4uptake displayed distinct diel and seasonal patterns reflecting ecosystem respiration. Combining in situ flux data with laboratory investigations and a machine learning approach, we find biotic drivers to be highly important. Soil moisture outweighed temperature as an abiotic control and higher CH4uptake was linked to increased availability of labile carbon. Our findings imply that soil drying and enhanced nutrient supply will promote CH4uptake by Arctic soils, providing a negative feedback to global climate change.

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Publisher / Repository:
Nature Journal
Date Published:
Journal Name:
Nature Climate Change
Page Range / eLocation ID:
1095 to 1104
Medium: X
Sponsoring Org:
National Science Foundation
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