CH4 emission in the Arctic has large uncertainty due to the lack of mechanistic understanding of the processes. CH4 oxidation in Arctic soil plays a critical role in the process, whereby removal of up to 90% of CH4 produced in soils by methanotrophs can occur before it reaches the atmosphere. Previous studies have reported on the importance of rising temperatures in CH4 oxidation, but because the Arctic is typically an N-limited system, fewer studies on the effects of inorganic nitrogen (N) have been reported. However, climate change and an increase of available N caused by anthropogenic activities have recently been reported, which may cause a drastic change in CH4 oxidation in Arctic soils. In this study, we demonstrate that excessive levels of available N in soil cause an increase in net CH4 emissions via the reduction of CH4 oxidation in surface soil in the Arctic tundra. In vitro experiments suggested that N in the form of NO3- is responsible for the decrease in CH4 oxidation via influencing soil bacterial and methanotrophic communities. The findings of our meta-analysis suggest that CH4 oxidation in the boreal biome is more susceptible to the addition of N than in other biomes. We provide evidence that CH4 emissions in Arctic tundra can be enhanced by an increase of available N, with profound implications for modeling CH4 dynamics in Arctic regions.
|Number of pages||13|
|Journal||Environmental Science and Technology|
|Publication status||Published - 2023 Feb 14|
Bibliographical noteFunding Information:
This study was supported by the Ministry of Science and ICT of Korea (2020R1I1A2072824, 2020M1A5A1110494, PN20081, 2021M1A5A1075508, PN22012, and 2022R1I1A1A01071925), Ministry of Environment of Korea (2022003640002), and the Ministry of Education of Korea (2019H1A2A1076239 and 2021R1A6A3A03039376).
© 2023 American Chemical Society.
All Science Journal Classification (ASJC) codes
- Environmental Chemistry