Mind bog-gling new study reveals Marsden Moor stores over a million tonnes of carbon

Best known as a popular spot for tourists and walkers in West Yorkshire, and sandwiched between the conurbations of Leeds and Manchester, this 2,300-hectare moorland (5,683 acres) has provided weekend fresh air for generations of mill and office workers.

Now there is evidence that these windswept uplands hold between 1 to 1.5 million tonnes of carbon in their ‘millennia-old’ peat, highlighting the vital role that healthy blanket bogs play in the tackling the climate emergency. It also shows the importance of preserving and restoring the moorlands, to prevent vast amounts of carbon from being released into the atmosphere.

The carbon estimate was obtained by a team of researchers from the School of Geography at the University of Leeds, led by palaeoecologist Dr Antony Blundell, working together with nine dedicated community volunteers and Rangers from the National Trust to carry out an assessment of peat depths and stratigraphy (the make-up of different layers of peat which were created over time).

Across more than 100 days over a four-year period, the team measured the depth of the peat at 2,290 set locations across the entire Marsden Moor estate – covering nearly every hectare of the windswept moorlands.

This research provided an accurate estimate of the total amount of peat across the estate - around 21 million cubic tonnes – allowing the team to calculate the amount of carbon stored as between 1 and 1.5 million tonnes.

This work followed on from a smaller study carried out in 2019, of a 350-hectare site known as Blakeley Clough in the Wessenden Valley on the moors, which found around 300,000 tonnes of carbon had been sequestered there.

Further studies are ongoing at 60 of the sample locations to analyse how bulk density and carbon content varies with location and depth, which will facilitate a more robust final site-wide carbon estimate.

Dr Antony Blundell, a senior researcher into peatlands at the University of Leeds, said: “A good carbon storage estimate is extremely important as it can illustrate the value of these moorlands and their role in mitigating climate change. The work of the volunteers has allowed us to gather much more data than we would normally have available – so we expect a really robust estimate of carbon storage to be derived from this project.”

As well as revealing the capacity of the peat for holding carbon, the team has been able to learn a lot more detail about how the peatlands were formed and their current condition. Through some initial radiocarbon dating, they have confirmed that the peat started to form locally in some areas as early as 10,000 years ago and then spread from Mesolithic times, ‘blanketing’ the landscape.

Dr Blundell explained: “Peat on average forms at up to 1mm per year, and the deepest areas of peat discovered were over five metres deep. In some locations, some depths showed evidence of Stone Age fires while other sites at other depths had evidence of ancient trees including pine and birch, and others again showed partially degraded vegetation.

“From these preliminary findings, we can begin to create a database of peat quality and constituents linked to the vegetation across the estate, which should be unique in the UK.”

Dr Blundell concluded: “Peat is like a book – once you can read it, you can understand the history of a place and how you might restore it.”

Ian Dowson, Marsden Area Ranger for the National Trust said: “The volunteer team has been able to locate areas where Sphagnum moss and cotton sedges are strongly preserved in the peat but are not present today because of 200 years of industrialisation and pollution. We are confident that they can flourish again with the help of restoration efforts.”

These restoration efforts are ongoing on the moor, where Trust rangers work with partner organisations such as Moors to the Future, Yorkshire Water, and the West Yorkshire Combined Authority, to restore bare patches of peat, to plant Sphagnum moss and other native species of plant, and to lower the risk of moorland fires, which can damage the peat and allow carbon to disperse.

The slow decay rates of Sphagnum moss can contribute positively to the future accumulation of organic matter at the estate, building peat soils and locking away carbon.

To help the process of planting more Sphagnum moss, the Trust has now set up its own Sphagnum moss nursery - the first established by the charity - where plugs of the wonder plant are being cultivated for the first time, ready to be planted out this autumn.

The need for moorland restoration is an urgent issue on a global scale. According to the International Union for Conservation of Nature, (IUCN), emissions from drained and damaged peatlands are a significant contributor to climate change. Estimated at 1.9 gigatonnes of CO2e annually, equivalent to five per cent of global anthropogenic greenhouse gas emissions; the risk is disproportionately high, considering damaged peatlands cover just 0.3% of landmass.

It’s therefore vital the landscape – which has historically been degraded by atmospheric pollution – is protected to make sure no more captured carbon is allowed to escape.

Tia Crouch, Peat Ecologist for the National Trust, said: “The National Trust owns around 25,000 ha of peatland across England, Wales and Northern Ireland, of which 70% (17,500ha) is currently in a degraded condition.

“Healthy peatlands are a ‘climate action trump card’. Our vision is to have all the degraded peatlands in our care under restoration by 2040 – aiding the recovery of peatland and the wildlife it supports and saving 140,000 tonnes of carbon emissions per year. We are making good progress towards this ambition with restoration underway across nearly 6,000 hectares since 2021.”