Afforestation of cut-away peatlands and peat fields

Does afforestation of peat fields restrain GHG emissions?

The study showed that peat fields in agricultural use were significant sources of carbon dioxide (CO2) and nitrous oxide (N2O), as well as mild methane sinks. Afforestation did not decrease the relatively significant emissions of N2O. In fact, winter-time emissions of N2O were even more substantial than emissions in the summer. Peat fields remained as mild methane sinks also after afforestation.

The age of the tree stand, tree species, the thickness of peat layer or ground water height seemed to have little effect on the decomposition of peat and hence, CO2 emission from soil. In afforested peat fields the decomposition of old peat remained at quite a high level in spite of afforestation. Due to the high peat nitrogen stores, peatlands have a high wood production potential, provided that the mineral nutrition of trees is balanced. Accumulation of carbon in the tree stand can partly compensate for the carbon loss from soil. According to preliminary calculations, most stands at the age of 30 are already carbon sinks.

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