Teagasc and NUI Galway have been awarded almost €600,000 in funding from the Department of Agriculture to research how best to manage the rewetting of peat soils.

The project will focus on water table management on carbon-rich soils. There is an estimated 300,000ha of grassland on drained carbon-rich soils across Ireland.

The Climate Action Plan, unveiled by Government in November, included a plan to target 80,000ha of grasslands on drained organic soils for reduced management intensity, or rewetting.

Much of this land is currently used for beef, sheep and dairy production.

Potential challenges

The plan acknowledged some of the potential challenges ahead for this 80,000ha target, noting that the “willingness of farmers to rewet their land if incentives were offered is difficult to predict as the level of farming intensity that can be sustained post-reduced management intensity is farm- and site-specific”.

Annexes to the Climate Action Plan, published in December, revealed that the interim target is to have 40,000ha of land under reduced management intensity by the end of 2027.

Rewetting these soils to improve sequestration and preventing additional carbon release will rely on manipulating the water table by removing and blocking existing artificial drainage features, according to Teagasc.

Main objective

The main objective of the joint research project, known as REWET, is to assess how water tables in different areas respond to manipulation through removing drains and also to look at the costs involved and the resulting benefit of rewetting the land.

The ultimate aim is to develop rewetting methods for peat soils that will then be used as the basis for management of peat land, reducing the impact of greenhouse gas emissions on the environment, promote improved soil health and support sustainable habitats at all scales.

REWET project

Patrick Tuohy and Eoin Fenton will work with Mark Healy and Eve Daly of NUIG on the project.

“The nuts and bolts of how best to rewet land are not really there,” Tuohy told the Irish Farmers Journal. “What will work in some locations may not work in others.

“There are around 300,000ha to 350,000ha of these drained soils and, under the climate plan, around a quarter of that is going to be rewet,” he explained.

“We’re also going to look at the cost per hectare of rewetting, including the cost of the work, but also the cost to farm production, and the carbon sequestration dividend it yields.

“We will look at the impact on surrounding land too, on neighbouring farms.”

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Watch: from cutting turf to rewetting the bog in Co Donegal

Carbon budgets: 175,000ha of peatland and grassland to be rewetted