HoliSoils research explores the long-term impacts of clear-cutting on soil carbon
Clear-cutting as a forest management practice is often criticized for its environmental impacts, but the practice and its consequences are actively debated. While clear-cutting temporarily turns forests into carbon sources rather than carbon sinks, these changes also have lasting effects, particularly on C stocks, that need to be understood over complete forest rotations.
Focusing on soil organic carbon (SOC), researchers studied two long-term forest monitoring sites in Finland (Scots pine and Norway spruce) that had been clear-cut and where SOC stocks time series have recently been measured. They used a soil carbon model (Yasso) to assimilate all the information from the data and then clear-cutting with a reference set-aside scenario over more than one full forest rotation.
The results of the modelling exercise, published in a new paper, showed that while thinnings operations didn’t significantly affect carbon storage, clear-cutting had major impacts. Each clear-cut event created negative soil carbon balance for decades, and it took 37-69 years for the forest soils to reach a break-even point where new carbon uptake compensated for the carbon lost. The biggest sources of carbon emissions after clear-cutting came from leftover harvest materials, followed by dead roots and fallen leaves.
When comparing managed forests to unmanaged ones, the clear-cut areas had negative soil carbon budgets until the next thinning or even the next clear-cut, while unmanaged forests consistently stored carbon in their soils. This suggests that forest carbon studies ignoring long-term soil effects may reach misleading conclusions, and that rotation forestry could not be a very effective management approach if carbon storage is a priority.
This article was written by Lorenzo Menichetti (Natural Resources Institute Finland).
More information:
Menichetti, L., A. Lehtonen, A.-J. Lindroos, et al. 2025. “Soil Carbon Dynamics During Stand Rotation in Boreal Forests.” European Journal of Soil Science 76, no. 4: e70154. https://doi.org/10.1111/ejss.70154.
