As everyone knows, the fourth Sunday of July is World Bog Day.
OK, maybe it isn’t as well known as World Book Day, but it’s still worth celebrating.
Peatland bogs can be found in around 180 countries around the globe. Although they cover just three per cent of total land area, they store around twice as much carbon as all the world’s forests.
And they’re increasingly at risk from human activity. As well as direct damage from air pollution, agriculture and exploitation, they’re being dried and burnt by rising temperatures and changing weather patterns.
The damage is being driven by increasing levels of greenhouse gases. And when peat bogs are damaged, they add to the problem. Globally, about four per cent of human-induced greenhouse gas emissions come from degraded peatland.
Remarkably, given its size, the UK is home to about 13 per cent of the world’s peat bogs. At least four-fifths of that has been damaged.
The UK’s peatlands currently store some 3.2 billion tonnes of carbon. If that’s burnt or otherwise oxidised, it would release over 10 billion tonnes of carbon dioxide, or about 30 years’ worth of our current territorial emissions.
Clearly, our bogs are worth protecting.
A walk around the bogs
For World Bog Day, I joined a walk led by the National Trust around the Marsden Moor estate, in the Pennines west of Huddersfield.
Sitting right at the top of the Peak District National Park, Marsden Moor is also a Site of Special Scientific Interest, Special Protection Area and Special Area of Conservation, thanks to its blanket bog and ground-nesting birds.
By one recent estimate, Marsden Moor is home to over one million tonnes of peat. The deepest parts of that were laid down over 6,000 years ago. More recently, given its location in one of the world’s first industrialised regions, it’s been battered by pollution.
In core samples drawn from the moor, the top inches of peat are visibly darker and denser than the deeper and older material. That means it’s less effective at holding water, so heavy rainfall on the tops can quickly lead to flooding on the valley bottoms.
The National Trust is now working with partners including the Moors for the Future Partnership to rewet the moorland, keeping more water on the tops where it can reduce the risk of both fires on the tops and floods in the towns below.
Visiting after a string of record-breaking heatwaves, the view on the tops wasn’t quite as parched as I’d thought it might be, but it was still the driest I’ve seen it.
Too much of the top is now dominated by purple moor-grass, which crowds out other species and increases the risk of fire when it dries to dense tussocks.
Thanks in part to the restoration programme, there’s a good show of bilberry and bog cotton. I also spotted a few stumpy willows lurking in hollows, a good sign of wet ground.
Helping hands
The walk highlighted a few of the long-term interventions to better understand and mitigate the effects of the changing climate on the bogs. We met volunteers who have planted rust rods at 23 points across the moor, to measure changes in the water table through the year.
There’s also the charming Eyes on the Bog project. Metal sculptures of a curlew and mountain hare provide fixed points for walkers to photograph the landscape, providing valuable information about how the moor changes over time.
On the lower and less peaty flanks of the moor, work includes new plantings of local trees such as rowan, oak and birch to help prevent erosion and keep water on the moors.
Returning to Marsden, we finished the visit (after some delicious chocolate bog cake) in the National Trust’s first sphagnum nursery. Here, volunteers cultivate the invaluable moss, which can hold up to 40 times its weight in water. Then comes the painstaking work of planting it, alongside beneficial native species of cotton grass and heather, across the heights of the moor.
Peatland bogs may seem like a small part of the global climate crisis, but they have a vital role in our shared ecosystem and need protecting. They can also be a fantastic place to visit. Happy World Bog Day to all.
