- 1Chair of Soil and Plant Systems, Brandenburg University of Technology Cottbus-Senftenberg, Cottbus, Germany
- 2Centre for Microbiology and Environmental Systems Science, University of Vienna, Austria
- 3Department of Biology, Lund University, Sweden
- 4Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
Arctic wildfires disrupt biogeochemical cycles of carbon (C), nitrogen (N), and phosphorus (P), which challenges exposed tundra ecosystems. In this study, we investigated the legacy of variable fire intensity on soil microbial nutrient cycling in field experiments on Disko Island, West Greenland, three years post-fire. Despite finding no significant differences in gross N mineralization and consumption rates, high-intensity fire-treated soil microbes exhibited reduced degradation of a protein substrate in soil chips, suggesting altered microbial activity in organic N cycling pathways. These results highlight the return of some biogeochemical processes over time, and also reveal potential vulnerabilities in microbial communities and their functionality in legacy after high-intensity fire. As fire frequency in the Arctic is expected to increase due to climate change, long-term consequences for ecosystems may include shifts in microbial composition and nutrient cycling, and slow ecosystem recovery. The feedback could alter greenhouse gas emissions, accelerate permafrost thaw and cause ecosystem transformation. Understanding these processes is critical for predicting the wider ecological effects of more frequent and intense fires. Future research should focus on multi-temporal sampling and microbial dynamics to better capture fire-induced alterations and their cascading effects on Arctic ecosystems and global climate regulation.
How to cite: Rodas, S., Arellano, C., Hammer, E. C., Zou, H., Klingammer, F., Ambus, P., and Rütting, L.: Arctic tundra soil microbiology retained effects from controlled in situ fire after 3 years, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-15164, https://doi.org/10.5194/egusphere-egu25-15164, 2025.