Refining emissions from grassland peat soils
Patrick Tuohy, Owen Fenton, Lilian O’Sullivan and Conor Bracken tell us about Teagasc research which has revised estimates of greenhouse gas emissions from grassland peat soils, reducing them from 9Mt to 3.9Mt CO₂e annually.
Greenhouse gas emissions from grassland peat soils were previously estimated at approximately 9Mt CO₂e per annum, making this the highest-emitting category from the land use, land-use change and forestry sector (LULUCF). This estimate was based on assumptions regarding the drainage status of these soils.
Teagasc research highlighted the nature of these assumptions and proposed refined emissions estimates, which have been incorporated into the updated EPA National Inventory Report (March 2024). These estimates have significantly altered the wider understanding of the emission profile and the management of these soils, currently and into the future.
The study offered new insights into the drainage status of grassland peat soils. It showed that the extent of peatland drained for agriculture had been thus far overestimated in national inventory reporting. Evidence for these emission savings were garnered by compiling decades of evidence related to the drainage status of peat soils and data from national scientific literature. This evidence enabled a more accurate figure for grassland peat drainage status to be used in the national inventory.
These findings have directly and significantly reduced the estimated emissions from grassland peat soils (and the LULUCF sector more broadly) by 5.1Mt CO₂e per annum (from 9Mt to 3.9Mt, equating to approximately 7.5% of the total national emissions from all sectors as previously estimated).
This change will inform and have a considerable influence on future policy around such soils regarding their management, and their rewetting and restoration potential.
In any given year, the impact of Teagasc research is a combination of the continuing impact of past research and the new impact of recent research. The most recent publication highlights some of these new impacts achieved in 2023.