A1 Journal article (refereed)
Emissions of atmospherically reactive gases nitrous acid and nitric oxide from Arctic permafrost peatlands (2022)

Bhattarai, H. R., Marushchak, M. E., Ronkainen, J., Lamprecht, R. E., Siljanen, H. M. P., Martikainen, P. J., Biasi, C., & Maljanen, M. (2022). Emissions of atmospherically reactive gases nitrous acid and nitric oxide from Arctic permafrost peatlands. Environmental Research Letters, 17(2), Article 024034. https://doi.org/10.1088/1748-9326/ac4f8e

JYU authors or editors

Marushchak, Maija

Publication details

All authors or editors: Bhattarai, Hem Raj; Marushchak, Maija E; Ronkainen, Jussi; Lamprecht, Richard E; Siljanen, Henri M P; Martikainen, Pertti J; Biasi, Christina; Maljanen, Marja

Journal or series: Environmental Research Letters

eISSN: 1748-9326

Publication year: 2022

Publication date: 11/02/2022

Volume: 17

Issue number: 2

Article number: 024034

Publisher: IOP Publishing

Publication country: United Kingdom

Publication language: English

DOI: https://doi.org/10.1088/1748-9326/ac4f8e

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/80405

Abstract

Soils are important sources of nitric oxide (NO) and nitrous acid (HONO) in the atmosphere. These nitrogen (N)-containing gases play a crucial role in atmospheric chemistry and climate at different scales because of reactions modulated by NO and hydroxyl radicals (OH), which are formed via HONO photolysis. Northern permafrost soils have so far remained unexplored for HONO and NO emissions despite their high N stocks, capacity to emit nitrous oxide (N2O), and enhancing mineral N turnover due to warming and permafrost thawing. Here, we report the first HONO and NO emissions from high-latitude soils based on measurements of permafrost-affected subarctic peatlands. We show large HONO (0.1–2.4 µg N m−2h−1) and NO (0.4–59.3 µg N m−2h−1) emissions from unvegetated peat surfaces, rich with mineral N, compared to low emissions (⩽0.2 µg N m−2h−1 for both gases) from adjacent vegetated surfaces (experiments with intact peat cores). We observed HONO production under highly variable soil moisture conditions from dry to wet. However, based on complementary slurry experiments, HONO production was strongly favored by high soil moisture and anoxic conditions. We suggest urgent examination of other Arctic landscapes for HONO and NO emissions to better constrain the role of these reactive N gases in Arctic atmospheric chemistry.

Keywords: soil; arctic region; ecosystems (ecology); biogeochemical cycles; denitrification; nitrification; emissions; nitric oxide; atmospheric chemistry