Funds plea to help farmers cut peatland carbon loss
FARMERS and conservationists are pioneering ways to reduce the environmental impact of farming on peat, as pressure mounts to cut emissions from UK peatlands.
And there are calls for funding focused on peatlands to help farmers switch to more sustainable systems.
Lowland agricultural crop and grassland peat soils that have been drained, ploughed and fertilised account for more than half of the 23 million tonnes of annual carbon dioxide emissions from UK peatlands, according to analysis led by the UK Centre for Ecology and Hydrology.
Jack Clough, from the University of East London’s Sustainability Research Institute, said where carbon-rich peatlands have been drained, microbes convert peat to carbon dioxide in the presence of oxygen, “literally turning peat into thin air”.
The peat is disappearing at the rate of around 1cm to 3cm (1.18in) a year, and where the water table is well below the surface – typically around 40-100cm (15-39in) because of drainage, it produces about 25-40 tonnes of carbon dioxide per hectare a year, he said.
Soil scientist-turned farmer Stephen Briggs, who farms on peat and clay in Cambridgeshire, said: “The only way to completely stop peat degradation, from losing these peat soils, and completely reducing carbon emissions is to stop farming them and to reflood them.”
But that has implications for livelihoods, the economy and food security, he added.
The Water Works project by Bedfordshire, Cambridgeshire and Northamptonshire Wildlife Trust is trialling a radical solution that involves reflooding the land while maintaining productive farming.
The wet farming, or paludiculture experiment, funded by the People’s Postcode Lottery, has created test beds where the water table will be kept to within 10cm (4in) of the surface to prevent carbon loss. Crops include bulrush, which could be used for insulation, and sweet manna grass
– a gluten-free grain.
The crops have all survived the very wet winter and dry April, although local Chinese water deer treated the flag iris as a salad bar, said Kate Carver, of Bedfordshire, Cambridgeshire and Northamptonshire Wildlife Trust.
Ms Carver said: “Through our field-scale trials and monitoring programmes, we aim to prove that wet farming can prevent the loss of carbon, prevent the loss of peat soils, clean water, and support wildlife.”
Mr Clough, with colleagues, is monitoring the carbon emissions, soil surface levels and water table at the Water Works scheme.
He said research showed each 10cm increase in the water table could reduce emissions from the peat soils by around three tonnes per hectare per year.
“There is real potential for public and private finance to expand paludiculture, which will make a positive difference to the way we manage our peat,” he said.
A Defra spokesman said its lowland agricultural peat task force was looking at how farmed peatlands could be better managed to reduce greenhouse gas emissions and to safeguard profitable agriculture. The group is co-ordinating work already under way and exploring new solutions, including innovative ways to manage peatland water-table levels.”