Between light and dark, source and sink: N2O dynamics in a subarctic, nutrient-poor permafrost peatland
Triches, N., A. Bolek, M. Rovamo, R. Lamprecht, W. Hashmi, T. Yazbeck, K.Ivanova, N. Eves, D. Paul and A. M. Virkkala. 2025.
Abstract
Global warming and permafrost thaw in the Arctic raise concerns about increased green
house gas emissions. Nitrous oxide (N2O) is a potent greenhouse gas produced in soils, but
its uxes from nutrient-poor Arctic peatlands remain poorly quanti ed. Here, we present
1,487 chamber ux observations across three snow-free seasons in a nutrient-poor thawing
permafrost peatland. Our results reveal this ecosystem acts as a continuous, albeit small
N2O sink during the snow-free season. We also identify a persistent N2O hot spot, indicating
substantial localised production potential. Complex interactions between photosynthetically active radiation (PAR), CO2 uxes, and other environmental factors drive N2O uxes, with
PAR being important but not exclusive. Di erences in drivers and response shapes were ev
ident between light and dark conditions. These ndings highlight non-negligible N2O uxes
in nutrient-poor Arctic soils and the signi cance of hot spots for landscape-scale budgets.
The critical role of soil%u2013plant%u2013atmosphere interactions and light as a driver has implications
for global greenhouse gas budgets and climate mitigation, underscoring the need for further
research.
