ANALYSIS: Why Yorkshire's peatlands are worth protecting

There’s a reason for that. The peat beneath your feet will probably be at least six feet deep. In some places in Yorkshire it’s up to 40 feet deep. And because peat holds water, it’s a bit like walking on top of a giant, wet sponge – just denser and firmer.

Yorkshire’s peatlands were formed over thousands of years by the slow growth of sphagnum moss. It’s a tiny little plant that grows from the tip. Over time, layers build up. As new moss grows on top, the dead moss below is compressed – in damp, acidic conditions caused by the sphagnum itself – to form peat.

The stony backs of the Pennines and parts of the North York Moors are covered in thick blankets of the stuff. It doesn’t make for the most diverse of landscapes – you’re likely to see just the bog moss itself, and cotton grass, some heather, and a few cloudberries and crowberries.

But it is special. You may, if you know what you’re looking for, spot rare and endangered plant species such as carnivorous, insect-eating sundews. And for walkers who enjoy Yorkshire’s upland places the peatland has a strange, eerie beauty all its own.

It is hugely important in other ways, too.

The thick layers of peat act like a reservoir, for a start – according to the Yorkshire Peat Partnership, up to 10 per cent of the Earth’s fresh water is stored in peatlands like these. And peat plays what is possibly an even more important role, too – as a carbon trap.

Peat is essentially organic carbon. And it is estimated that between them, the world’s peatlands lock away something like 500 gigatonnes of peat – more than twice the carbon locked up in all the world’s forests.

Even more important, healthy peat bog continues to absorb carbon as it grows. “It takes in carbon dioxide from the atmosphere and stores it,” says Tim Thom, programme manager of the Yorkshire Peat Partnership.

Dammed drainage ditches in peat moor at Nidderdale. Photo: Matt Cross

So as long as they remain healthy, then, Yorkshire’s peatlands are acting as a giant carbon scrub, sucking C02 out of the air and helping to slow climate change.

The trouble is, the world’s peatlands aren’t healthy.

The Yorkshire Peat Partnership estimates that about a quarter of all the world’s peatlands have already been destroyed. In Indonesia, for example, great swathes of forest are being burned back to make way for palm oil plantations. But the forest grows on peat – and the peat is burned too, releasing huge quantities of carbon into the atmosphere.

The continuing global degradation of peatlands is releasing something like 3,000 megatonnes of carbon dioxide into the air each year, accounting for more than a tenth of all global greenhouse gas emissions, the Yorkshire Peat Partnership says.

Our own peatlands aren’t immune. Across the UK, something like 95 per cent of peatlands have been damaged. And since the middle of the last entry, the damage has been as bad in Yorkshire as it has anywhere else.

During and after the Second World War, there were attempts to drain the peatlands to create more grazing land. Drainage ditches were cut all over the Yorkshire uplands. This had the disastrous effect of lowering the water table and drying the peat out, so it began to erode. “It didn’t create more grazing, but it wrecked the peat,” says Andrew Walker of Yorkshire Water, which is one of the agencies involved in the Yorkshire Peat Partnership.

Yorkshire’s peatlands are also under threat from overgrazing, from acid rain and airborne pollution (especially in the southern Pennines, where peatland is surrounded by large cities such as Sheffield and Manchester), and from out-of control fires.

Yorkshire Water's Andrew Walker inspecting sphagnum moss

In the Nidderdale area, some of those fires were actually caused by training exercises during and after the war, when aircraft went down on the moors. “There’s evidence that we’re still trying to deal with the effects of these fires 60 years on,” says Mr Thom.

The degradation of peatland in Yorkshire has been so bad that even the water quality has been affected.

That is evident in the increasing discolouration of the water, says Andrew Walker. It has become ever browner – a sign that sediment from peat is leaching into the water.

That happens when the peat dries out. You’re always going to get some discolouration, Mr Walker says, but it became much worse after the drought of 1985. “Water colour levels jumped up.”

That causes real problems for the water company, because treating discoloured water is expensive. You can’t just filter it, it still comes out discoloured with tiny peat particles. So it has to be chemically treated.

Walkers will be familiar with the tell-tale signs of peatland erosion. You see drainage ditches so badly eroded they have developed into huge gullies.

Then there are peat hags – “dunes” of peat, often crowned by small clumps of vegetation but each surrounded by lower areas where the peat has dried out and blown away. There are even areas of bare peat – some huge – where nothing, not even moss, grows at all and the peat itself is completely exposed.

Peat hags in Bishopdale, south of Wensleydale

This peatland degradation is an environmental disaster, the Yorkshire Peat Partnership says. Since 1990, it says, the emission of carbon dioxide from peatland has increased by 25 per cent.

The good news is that, in the UK and Yorkshire at least, the fightback has begun.

In Yorkshire it’s a process that started in the 1990s, when we began reducing livestock grazing on peatland. But things really took off less than ten years ago.

The Yorkshire Peat Partnership was set up in 2008, and it began a long-term process of peatland restoration. Drainage ditches are being dammed to raise the water table and stop peat drying out.

And areas of peat that are eroded or bare are being “innoculated” with sphagnum moss to try to restart the peat-growing process.

The Yorkshire Peat Partnership now spends about £2million a year on peat restoration, while Yorkshire Water has its own restoration programmes.

It’s a slow process. “It grows really slowly,” says Mr Thom. “We’re trying to restore something which has taken 5,000 years to grow.”

Sphagnum moss: the vital ingredient of healthy peatlands

But 3,000 kms of drainage ditches have now been dammed, and sphagnum moss has been reintroduced on peatlands from Nidderdale and Colsterdale Moor near Masham to Humberstone Bank at Harrogate and Keighley Moor, Yorkshire Water’s first big peatland restoration scheme. “And we are seeing signs of recovery,” Mr Thom says.

Let’s hope that continues.

THE BATTLE TO RESTORE YORKSHIRE'S PEATLAND

Even within Yorkshire, every peatland is different, says the Yorkshire Peat Partnership. So the exact restoration method used depends on the way in which peatland has been damaged.

Here are some of the things being done:

Smaller eroded gullies: Peat dams are used. Peat is gathered from beside the gully and used to create a wedge-shaped dam

Larger eroded gullies more than one metre wide: either stone dams or wooden “sediment traps” are used. The latter slow the flow of water without stopping it altogether – allowing sediment to settle out of the water and build up behind the dam

Peat hags – “dunes” of peat surrounded by eroded areas. These typically have very steep sides of bare peat, when nothing can grow to stop the erosion. Hags are reprofiled to make the sides less steep. The vegetation growing on the top is rolled back, some peat removed, and the vegetation put back in place. The peat that was removed is then used to rebuild the sides of the hag to make them less steep, so natural vegetation can grow and stop the erosion

Reprofiling peat hags at Nidderdale. Photo: Joanna Richards

Bare peat: this is often “innoculated” with sphagnum moss – either by using cut sphagnum fragments transferred from healthy peat bog, or by using sphagnum propagated in a growth medium. Alternatively, bare peat can be treated with a brash of heather or cotton grass, which aims to provide a plant covering that will enable sphagnum moss to start growing again

FOUR GOOD REASONS TO PROTECT OUR PEAT BOGS

Biodiversity: blanket bog is a unique environment supporting rare and endangered species, including sundews, a carnivorous, insect-eating plant.

Carbon storage: Peatland locks up carbon that would otherwise be released into the atmosphere. The Yorkshire Peat Partnership estimates that the world’s peatlands hold the equivalent of 100 years worth of global fossil fuel emissions. Healthy peat, meanwhile, draws carbon dioxide out of the atmosphere, acting as a natural “carbon scrub”.

Water quality: damaged, eroded peatland means more sediment in the water, making it more expensive to treat: one of Yorkshire Water’s main reasons for being involved in peatland restoration.

Flood control: healthy peatland helps to naturally slow the flow of water, meaning it takes longer to flow down from the hilltops.

WHAT IS THE YORKSHIRE PEAT PARTNERSHIP?

The Yorkshire Peat Partnership includes The Yorkshire Wildlife Trust, the Yorkshire Dales National Parks Authority, Natural England, North York Moors National Parks Authority, Yorkshire Water and the Environment Agency. It also receives support from the Nidderdale AONB, Pennine Prospects, the National Trust, the Moorland Association, the National Farmers Union and the Yorkshire Dales Rivers Trust.

To find out more, visit www.yppartnership.org.uk/