Benefits of Offaly bog restoration outlined for National Biodiversity Week

RESTORING Bord na Mona's cutover bogs will enhance biodiversity and help with decarbonisation, one of the company's ecologists said last week.

To mark National Biodiversity Week, David McNicholas led a walk at Lough Boora Discovery Park last Friday and outlined Bord na Mona's plans for 33,000ha of its peatlands around the country.

Government and European Union funding worth some €117m is being invested through the company's Peatlands Climate Action Scheme and many workers formerly employed in peat harvesting are now employed on the new project.

Bord na Mona's 'brown to green' strategy originally envisaged peat production being phased out by 2030 but the timeline was accelerated by a High Court ruling against the energy company.

“Bord na Mona would have been one of the main employers in the Midlands and all of a sudden peat production ceased and there were a lot of job losses associated with that,” said Mr McNicholas.

While Bord na Mona continues to be active in wind energy and has plans for solar farms, significant numbers of staff have switched to bog rehabilitation.

They do this by blocking the drains which were previously used to dry out vast areas of bog in advance of industrial harvesting for peat-fired power stations, briquette manufacture and horticulture products.

Engineers and hydrological consultants are involved in the work and they survey the various bogs.

The correct proportion of water creates the conditions where peat begins to form once again, with acidic concentrations necessary to promote the growth of sphagnum moss, the building block of the peatlands.

“The plan is to implement really intensive measures of drain blocking where we can work with the topography of the bog to try and optimise the water level within the peat to within 10 cm above or below the peat to try and create peat forming conditions again,” said Mr McNicholas.

If there is residual deep peat, for example depths of more than two metres, the water will be acidic. With shallower peat the conditions are more alkaline and stimulating sphagnum growth is more difficult, resulting in a fen-type landscape instead, but some sphagnum does nonetheless appear.

“Depending on the fall in the bog we're putting in between three and seven drain blocks every 100 metres. It's quite intensive,” added the ecologist.

“The guys who were working on the bogs as part of the milling understood those bogs and know them intimately because they spent years on them.

“Their knowledge of the bog is brilliant because they know where you can't go with a machine.”

Bord na Mona is also now in a position to offer its expertise on a consultancy basis to other owners of large tracts of peatland, such as the National Parks and Wildlife Service.

Ceasing peat harvesting and rewetting the bogs results in natural regrowth, especially of birch, and Bord na Mona has also engaged in planting of other tree species.

Numerous grasses and wildflowers reappear and the narrow gauge rail lines are becoming pollinator corridors.

Reeds and other pioneering plants in turn result in invertebrates like flies and midges repopulating the bog and that attracts birdlife back as the peatland rewilds.

Boora is seeing hen harriers and whooper swans, among many others. Hen harriers are a protected species because of declining numbers and they breed in the Slieve Aughty mountains in Galway and Clare and then visit Boora.

Whooper swans (distinguished from the mute swans because of the sound they make) fly to Offaly from Iceland.

Along with the birds, animals like grey squirrels and pine martens are making their homes in Lough Boora.

Mr McNicholas explained that wetting the dried out bogs combats climate change by locking in carbon.

“The drain blocking is keeping that residual peat in the ground. [On cut bogs] it's kept high and dry so the oxygen in the atmosphere is getting into the peat and oxidising it and letting the carbon out,” Mr McNicholas explained.

“When we block those drains and get that water table up we keep that peat wet and in the ground and the carbon isn't getting in the atmosphere so we're meeting our carbon objectives.”

Bord na Mona has employed carbon specialists and they have erected monitoring towers on the bogs.

“They can tell you which direction the carbon is going, whether it's coming up out of the ground into the atmosphere or whether it's coming from the atmosphere down.”