Peatlands are globally important in terms of greenhouse gas (GHG) emissions as it is estimated that they comprise up to 30% of the total global soil carbon pool. As peatlands develop, the build-up of plant and animal remains creates a store of carbon in a waterlogged and anoxic environment. Because of this waterlogged condition, there is limited scope for microbes to break down the peat and release carbon dioxide. When peatlands are drained, carbon is released mainly in the form of carbon dioxide and dissolved organic carbon.
This is also true for Irish peatlands and the role of managing Ireland’s peatlands has been highlighted in the National Peatlands Strategy (2015) as being important for future carbon accounting at a national level. Most of the Bord na Móna bogs have been drained at some point. Where possible Bord na Móna is restoring raised bogs to peat forming conditions – stopping further release of carbon dioxide and in time restoring the carbon sequestration function of the bog.
Bord na Móna is also funding research into determining the rate at which this switch occurs, and a project monitoring GHG emissions from a restored bog (Moyarwood in East Galway) was established in 2013, and is expected to continue to 2018.
Two GHG monitoring projects have also been carried out to inform rehabilitation measures on cutaway bogs – one in the rehabilitated Oweninny Bogs and one in a rehabilitated cutaway bog in Blackwater Bog (West Offaly). Both studies show that rewetting of the cutaway and establishment of wetland habitats such as poor fen and reed bed, reduces carbon dioxide emissions and leads in time to carbon sequestration.
Each of the studies has informed national carbon accounting measures carried out by the EPA, and Bord na Móna’s Carbon Working Group established in 2009, tracks policy developments and accounting approaches in consultation with the EPA Climate Action team.