Peat bogs and climate change
Rob Stoneman – Chief executive – Yorkshire Wildlife Trust
Sphagnum is immortal.
Or at least it might be as it grows from its tip leaving only partially decomposed stems and leaves lower down in waterlogged peat, allowing the peat to accumulate and the plant to grow ever upwards. In this way, peat accumulates as a thick blanket across the hills or as low domes of bog in the lowlands.
As the glaciers receded to leave a wet landscape of lakes and bare moraine, many of the lakes gradually filled with sediment allowing Sphagnum to dominate, exploiting scarce nutrients with its intricate cellular arrangement of large hyaline cells and tiny photosynthetic cells. The swapping of nutrients for hydrogen ions acidifies the waters allowing Sphagnum to dominate whilst its growth pattern leads to peat formation. Eventually, the lake fills with sediment and peat and Sphagnum completely dominates the system allowing a dome of peat to grow up above the former lake surface. Here is a habitat that is created by and suited perfectly for this most primitive of mosses. Sphagnum is the king of the bogs.
On our hills, deforestation by Bronze Age farmers led to the leaching of thin hill-soils under high rainfall. Iron, leached from upper soil layers redeposited as an impervious layer – an iron pan. Impeded drainage, high rainfall and hill fog makes for ideal conditions for Sphagnum and upland Bronze Age farmland succumbed to bog-land – a blanket of peat across the Pennines and North York Moors.
This is wild land. A walk across the moors invokes a sense of freedom. “I may be a wage-slave on Monday, but I am a free man on Sunday”, goes the Ramblers song. That sense of wilderness comes, in part, from the unusual (for England) wildlife of the Moors – more akin to Siberia or northern Canada than temperate England. The rising bubbling trill of a curlew, the piping of breeding redshank, the fast-flighted zizz of dragonflies, a glimpse of mountain hare or the deep throated chuckling of red grouse are all deeply evocative of this seemingly untamed land.
And yet, as ever, these are habitats under threat. Afforestation, farmland ‘reclamation’ (drainage, ploughing, fertilising, seeding), peat cutting, industrial pollution and fire have all played a part to massively degrade our boglands. Indeed, by the late 1980s, conservationists realised that lowland raised bog exploitation was so rapid, this rare habitat would be gone by 2020. The Peat Campaign launched into action to stop peat cutting and reduce the use of peat in gro-bags and the like. Two decades on, the campaign was only a partial success. UK peat cutting has more or less been regulated out of Britain with some notable conservation successes. Most spectacular was the conservation of Thorne and Hatfield Moors, which cost the Government £17 million to buy out Scott’s peat extraction rights – the culmination of a long campaign with local naturalists (the Thorne and Hatfield Moors Conservation Forum) bravely leading the way with Yorkshire Wildlife Trust, RSPB and Friends of the Earth combining to make a defining case. Less successful, was the campaign to replace peat in horticulture with growing media made from recycled waste (coconut husks, bark mulches, green waste and the like). Whilst sales of peat alternatives have reached 50% in some stores, across the sector peat use has actually gone up. Instead of destroying British bogs, our insatiable demand destroys Russian or Estonian bogs – we have exported our environmental problems abroad.
On our hills, our blanket bogs have also fared badly. Moor-gripping (drainage), funded by the tax-payer, alongside over-grazing and burning mean that most blanket bogs are now degrading rather than accumulating peat. In the southern Pennines, industrial air pollution killed off the Sphagna leaving bare peat that has rapidly eroded, filling reservoirs with eroded peat and discolouring drinking water brown – at great cost to the water industry and ultimately us.
The Peat Campaign was all about conserving bogs for their wildlife value, their intrinsic beauty and their landscape. Today, the case for peatland conservation has been strengthened by another vital ecosystem service that peatlands provide – carbon storage.
Fossil fuel burning has increased atmospheric carbon dioxide from 220 parts per million (ppm) to over 360ppm today accelerating the greenhouse effect to a level that threatens climate chaos – reduced food production, the loss of half the world’s biodiversity and the flooding of all coastal cities (London and Hull for example) within a 100 years or so. The industrial revolution, powered above all by coal, and initiated here in the heart of England, has brought great prosperity but perhaps the cost will be too great for our civilisation to bear.
Coal – the fossilised remains of peat laid down in vast deep peat bogs in subsiding basins. A modern day analogy is probably the peat bogs of SE Asia. We have taken the laid down (sequestered) carbon from the time of the dinosaurs and released it back into the atmosphere. Peat bogs, then and now, from a massive store of global carbon. Worldwide, peatlands store 2,200 GtCO2e , equivalent to 35 years of human-caused greenhouse gas emissions. This vast store of carbon is in desperate trouble, with over half the world’s peatlands damaged in some way. For example, peatland drainage and associated peat swamp forest logging ensures that under-developed Indonesia is now the third-largest greenhouse gas emitter despite a low industrial base. In Britain, the sums are equally staggering. Britain’s bogs are so damaged, they are estimated to emit as much carbon per year as the entire British transportation system; likewise, if they were restored, they would sequester as much carbon again.
Peatland restoration thus offers a double win – the saving of carbon that would have been lost and re-initiated carbon sequestration. But is this possible?
To answer this, we need to wander around the UK. Let us start on a bog called Din Moss in Fife. Here a raised bog was drained and partly afforested some 120 years ago. Since then, the site has largely been ignored. The Scots Pines have matured and started to fall over. The drains long since filled in with debris and silt. A carpet of Sphagnum has spread across the fallen trees: natural restoration in action. At Langlands Moss, East Kilbride, the Scottish Wildlife Trust speeded up this process by removing all the confers and blocking ditches – the first large-scale trial to pave the way for major restoration programmes in the Flowe Country, Sutherland, on the Lochar Mosses in SW Scotland, on Roudsea Moss in Cumbria and on the border mires in Northumberland.
Meanwhile, back in Yorkshire, scientists at Sheffield University began to research the rehabilitation of cut-over bogs; research that allowed English Nature to begin the large-scale restoration of Fenns and Whixhall Mosses in Shropshire, the Solway mosses in Cumbria and most spectacularly of all the full-scale restoration of Thorne and Hatfield Moors here in Yorkshire. The dust-swirled killing fields of industrial peat extraction that blighted the moors have gone, replaced by shallow water lagoons resplendent with cotton grass and now showing the first bright green skin of Sphagna – the healing process has begun.
Fifty miles east of Thorne, on the blanket bogs of the southern Pennines, Moors for the Future have deployed helicopters, jute matting, hay-bales, limestone chips, grass-seed and heather brash to stabilise the bare peat of the Derbyshire and Yorkshire moors. The results are spectacular. The bare black mess of fast eroding moor is transformed into a green mosaic allowing Sphagna to get hold – a much needed return of this most keystone of species back into our Pennine moors.
In short, restoration is possible; the carbon gains can be achieved. The Yorkshire Wildlife Trust has long taken an active part in the peat campaign, especially in relation to the conservation of Thorne and Hatfield Moors. Today, we switch our focus to the high Pennine peats working in partnership with Yorkshire Water, the National Parks and Areas of Outstanding Natural Beauty, Natural England, Environment Agency and the National Trust. This partnership has set itself the realisable target of restoring all of Yorkshire’s peatlands to ensure Yorkshire contributes as fully as it can to reducing atmospheric carbon. At a national level, this Trust is working through the Wildlife Trusts partnership to unlock monies to spread the knowledge, expertise, money, research and networks to ensure all of the UK’s peatlands are restored.
The UK is an influential nation and by being an exemplar of good practice and expertise, it could enable the UK to bring the common sense required to the international negotiating table (the Bali Climate Change discussions) to ensure all the world’s peatlands (and forests) are protected to avoid climate chaos. The stakes have never been higher but the solutions are really rather simple and lie at the heart of the Gaia concept, where our civilisation merely facilitates the Earth to heal itself. We need to engineer the end of this Carbon Age and allow our forests, peatlands and seas to take the excess carbon out of the atmosphere. Human civilisation can do this but we must act now.