Turning bogs from wastelands to nature-scapes

You know when you are in a healthy peatland because it is soggy. The ground quakes when you walk on it and a misstep fills your boots with a brown cold liquor. It is no coincidence that the Irish word for soft — “bog” — also lends itself to these places that are not quite land.
A healthy bog can be 90 per cent water, more than the water in milk. It is not easy, but we can walk on bogs because of the astonishing water holding properties of sphagnum moss. This humble plant also performs the alchemy of drawing carbon dioxide out of the atmosphere to convert the gas into solid mass through photosynthesis.
Peat soils cover more than 23 per cent of the country, meaning many Irish people have long had close interactions with the peatlands, through their use for energy, agriculture, horticulture and forestry. There are also deep cultural attachments to bogs.
Literature, songs, stories, art and architecture draw from peatland landscapes and people’s experiences with community, work and nature in bogs. This close association between people and peatlands is critical for turning bogs from exploited wastelands to restored nature-scapes.
Peatlands are everywhere in Ireland and successful restoration of peatlands needs buy-in from the people who live in and among them. Catherine Farrell and colleagues recently argued for a strong “bottom-up” approach to peatland restoration that considers the deep links between peatlands and the landowners and communities that are their custodians.
Carbon is directly released from peatlands through the burning of turf. Carbon from plants like sphagnum is stored for decades or centuries without decomposing in the oxygen-poor, acidic water of peatlands. When turf is harvested, dried and burned with oxygen, carbon is released to the atmosphere as carbon dioxide, a potent Green House Gas. Stopping turf extraction, however, is not sufficient to prevent carbon loss. Carbon is also lost from degraded peatlands that are no longer harvested.
An astonishing 85 per cent of our peatlands are degraded. Drainage of peat soils for agriculture, forestry and commercial peat extraction has led to many peatlands becoming climate-damaging carbon sources rather than their natural state as carbon stores and sinks and repositories of biodiversity.
The colour of bog water comes from dissolved organic carbon, nitrogen and phosphorous as well as natural plant chemicals like tannins (which is what makes your tea brown). You can see a drained bog leaking carbon out in the brown bog water. The acceleration of carbon leakage from bogs over the past century is not a natural process, human drainage of peatlands is responsible for five per cent of global carbon emissions.
In a healthy soggy bog, the carbon dissolved in the water mostly stays there because there is not enough oxygen to convert it to carbon dioxide gas. When a bog is drained, however, the dissolved organic carbon leaks out where it mixes with the oxygen in faster running water to make carbon dioxide which escapes to the atmosphere.
Carbon dioxide and other greenhouse gases — methane and nitrous oxide — are also produced when bogs respire or breathe. Peatland soil is full of living organisms from bacteria to beetles that, like humans, take in oxygen and breathe out carbon dioxide. Where there is no oxygen there are bog organisms that do not need oxygen and can breathe out the greenhouse gases methane and nitrous oxide. A healthy bog balances the carbon being created through the photosynthesis of plants with the greenhouse gases being breathed out.
Bog restoration is delicate and expert work, requiring an understanding of the complexities of water flow in peatland systems together with expert engineering knowledge and the right equipment. Our peatlands are a rich heritage that have been used, abused and valued in different ways throughout history. We are entering a new era of peatland restoration that if done right will build on existing strong connections between people and peatlands and which will create new traditions of working with nature to build rather than degrade bogs.
Next time you pass a healthy peatland, tóg go bog é — tread softly — thousands of years of nature, and the benefits it provides, are under your soggy feet.
Prof Yvonne Buckley is the co-director of the Co-Centre for Climate + Biodiversity + Water at Trinity College Dublin