In a recent study published in Restoration Ecology, researchers from the University of Eastern Finland measured post-restoration Sphagnum moss layer growth on 18 peatland sites in Finland 10 years after restoration. According to the study, a thick Sphagnum moss layer forms rapidly during the first 10 years after successful restoration, with carbon sequestration rates commonly exceeding those of pristine bogs.

The average thickness of the Sphagnum moss layers was 15 cm, and the amount of carbon they sequestered corresponds to approximately 48 tons of carbon dioxide per hectare. This amount is greater than what could be expected based on previous studies.

The best Sphagnum moss growth was observed in nutrient-poor sites in Southern Finland that had been restored to open bogs. Such peatlands are most commonly selected for restoration, and their timber production is generally poor when they are drained. Another important observation was an increase in the water-table depth, which was caused by the thickness growth of the Sphagnum moss layer. This could possibly mitigate methane emissions from the restored peatland.

The climate impact of peatland restoration is a much-discussed topic, as modelling studies have not shown a cooling effect in the case of forestry-drained peatland restoration in Finland. This is partly due to a lack of research findings from restored peatlands. These newly published results are promising in terms of the climate impact; however, they only fill a fraction of the knowledge gap. The results can help improve restoration efforts towards the desired climate impact.

Research article:

Laatikainen, A., Kolari, T.H.M. & Tahvanainen, T. 2025. Sphagnum moss layer growth after restoration of forestry-drained peatlands in Finland. Restoration Ecology, e70008. https://doi.org/10.1111/rec.70008