New research indicates that restoration of peatlands can result in climate mitigation within just a few decades. In Finland, some 60,000 hectares of previously forestry-drained peatlands have already been restored, comprising mainly nutrient-poor sites with weak tree growth. In such cases, peatland plants remain viable and react rapidly to restoration, resulting in the formation of a thick new layer of Sphagnum moss.
Plant ecologist and lecturer Dr Teemu Tahvanainen at the University of Eastern Finland compiled available data and earlier results from drained and restored peatlands to inform a modelling study on climate mitigation potential of restoration. The results indicate that peatland restoration can contribute to between 2 and 6 CO2-equivalent tons per hectare of annual climate mitigation, in a one-hundred-year assessment perspective. The implication is that restoration of weakly productive forestry-drained peatlands could make a pivotal contribution to the land-use sector emission scenarios in Finland.
The study indicates better climate impact than earlier studies, where long-lasting warming impact had been indicated for the most common restoration cases. The study utilised results of moss growth and water level trends in restoration sites to infer carbon sequestration and methane emissions after restoration in a process-based modelling approach. In contrast, earlier studies had presumed instant recovery of pristine peatlands’ emission factors due to lack of data from restored peatlands.
The study focused on nutrient-poor and acidic peatlands, where proliferation of Sphagnum moss vegetation can result in a temporarily effective carbon sink. Such decadal-scale development after restoration typically leads to the establishment of relatively dry bog-type vegetation, while the target of restoration may have been set as a wet peatland type.
“This difference in the vegetation response likely dampens methane emissions, acting in favour of climate mitigation,” Dr Tahvanainen says.
The study was published in the journal Restoration Ecology.
Research article:
Tahvanainen, T. (2026) Restoration of forestry-drained oligotrophic peatlands can bring climate change mitigation within a few decades. Restoration Ecology DOI:10.1111/rec.70326
https://onlinelibrary.wiley.com/doi/10.1111/rec.70326
Video on the climate impact of peatland restoration: https://youtu.be/6isoAxVH_tI