Which carbon is the oldest in permafrost-affected soils?

High-latitude regions store significant amounts of global soil organic carbon, which is highly vulnerable to climate change. Most of this carbon is stored in frozen permafrost soils covered by boreal forests. Wildfires, which are predicted to increase in frequency and intensity, contribute to a long-term carbon pool that might compensate for wildfire emissions. Pyrogenic carbon, a byproduct of biomass burning, is derived from incomplete combustion of vegetation during wildfires and has higher chemical stability than its initial biomass. It consistently contributes to around 7% of the total soil organic carbon in the studied mineral soils, despite variability in ages. The age and quantity of pyrogenic carbon are controlled by soil and site properties, which will change in the future. Therefore, pyrogenic carbon is an important and substantially aged pool in permafrost-affected soils and needs to be considered in relation to future climatic changes and the carbon cycle of high-latitude regions.


Open access publication:
Schiedung, M., Ascough, P., Bellè, S.-L., Bird, M.I., Bröder, L., Haghipour, N., Hilton, R.G., Lattaud, J., Abiven, S., 2024. Millennial-aged pyrogenic carbon in high-latitude mineral soils. Communications Earth & Environment 5, 177. https://doi.org/10.1038/s43247-024-01343-5