Peatland: A Burning Issue

This is the second in a series of four blogs by Nic Wilson exploring the critical importance of peatland conservation and restoration as nature-based solutions to climate change. This blog explores the environmental problems created by rotational burning. It highlights a case study from RSPB Geltsdale Nature Reserve where restoration work has seen peat rewetted and where burning has been replaced with less damaging heather cutting.

History

Vegetation burning (e.g. heather and grass burning) has been an ongoing practice in upland Britain for centuries, even millennia. Prior to the mid-nineteenth century, fire was used to improve grazing for red deer and sheep, a practice which continues today. After the middle of the nineteenth century, managed burning also became standard practice to create favourable habitat for red grouse (Lagopus lagopus scoticus) production. Rotational burning aims to provide forage and cover for red grouse and grazing for sheep by creating a mosaic of young nutritious heather and older heather (Calluna vulgaris) for cover.

Today peatland in the English uplands can be legally burnt between 1 October – 15 April. Burning in the uplands is increasing with recent research finding a 7-fold increase in burning on peatland in England from the 1940s to the present time¹ and burning increased at a rate of 11% per annum between 2001 to 2011 in Great Britain². Information from Natural England suggests there are currently over 400 consents allowing burning on sites internationally important for birds and deep peatland habitats³. These are all in areas managed for red grouse production.

Carbon Storage

While some studies of the effect of peatland burning can show a short-term carbon gain due to rapid heather growth, the long-term effects demonstrate significant damage to peatland hydrology and peatland vegetation, with associated impacts on peat and stored carbon. Each year damaged upland blanket bogs in England emit 350,000 tonnes of CO₂ Three quarters of this arises from areas that are rotationally burned⁵. 

Impact on Nature

Whilst some researchers have argued that peatlands are not damaged by burning, a recent Natural England evidence review found that burning has a range of detrimental impacts on peatlands in the uplands⁶. In 2008, inappropriate burning was cited by Natural England as a reason for the poor condition of peatland sites in England, alongside overgrazing and drainage. Burning continues to have an adverse impact on the state of blanket bog – a recent UK Gov report (Article 17 report) concluded that the overall conservation status of blanket bog in the UK was unfavourable (bad) due to a combination of intensive grazing, burning, game management, air pollution and drainage⁷. Once peatland is burnt, the water table is lowered and heather more rapidly colonises the drier ground and out-competes the sphagnum mosses, changing the vegetation balance and ultimately the whole ecosystem. In time, the water table rises and peat-forming vegetation can recover but after many cycles of burn-recovery-burn, the site gradually transitions toward a drier (more heath-like) state.

Wildfire Risk

When peatland is subject to rotational burning, the heather cover becomes more vigorous and widespread. This contributes to further drying of the soils, increasing the risk of hot fires, particularly outside the prescribed burning season when unmanaged fires are more frequent. Although burning has been seen as a way of reducing the fuel load on peatland thereby helping slow the spread of a wildfire, this method of management also perpetuates the heather-dominated vegetation, necessitating repeated burning to mitigate fire risk. In addition, tall heather cover is far more likely to cause hot fires which can burn into the peat and kill the sphagnum ground layer, preventing recolonization and rewetting of the site. Rather than burning the vegetation, we need to rewet bogs by raising the water table and creating the conditions for peat-forming vegetation to recover, making the peatland more resistant to the impact of fire.

The most effective long-term sustainable solution for addressing the wildfire risk on peatland is to rewet the site and return it to a fully functioning peat bog habitat. This involves evolving the way we use large areas of bog and heath habitat, and acting to restore damaged sites by blocking drains and gullies, reducing grazing and stopping burning. Peatlands in an improved state would continue to hold grouse at sufficient numbers to allow some grouse shooting to continue.

RSPB actions

In 2012, the RSPB made a formal complaint to the European Commission about concerns over Natural England’s action in relation to an upland grouse shooting estate, Walshaw Moor, in the South Pennines. The case expanded to cover the way in which Natural England and the UK Government permits and financially supports the ongoing burning of our globally important upland peatland habitats, particularly blanket bog in protected Special Areas of Conservation in northern England.

In September 2018, the RSPB called for a stop to burning on upland peat bogs – only 4% of which are currently in a healthy state due to years of burning, overgrazing and drainage. In 2018/19, Natural England sought to negotiate a voluntary halt to rotational burning on grouse moors, as a precursor to the estates giving up just over 400 consents to burn blanket bog.  While a number of estates did agree to give up their permission to burn, the majority did not do so.  In line with its commitment to the European Commission to end burning of blanket bog by October 2019, the Government committed to bring forward new legislation to bring a halt to such burning.  However, we are still waiting for Government to deliver on its promise, despite recent statements by a Defra minister that it is working on the legislation.

Case Study – Peatland Restoration at Geltsdale

RSPB Geltsdale in the North Pennines is a mixed landscape of blanket bogs, woodland, heath, meadows and grassland. The site encompasses two large hill farms and is managed for nature, with blanket bog restoration taking place through reduced sheep grazing, replacing heather burning with cutting and blocking the artificial moorland drains. Since the restoration work began, there has been a steady improvement in the condition of the blanket bog with 43% of plots in favourable condition by 2012, up from 10% in 2000.

As a result of the shift from burning to vegetation cutting, sphagnum continues to spread, with 14 species recorded across these areas along with increases in the distribution and frequency of other specialised blanket bog species. Curlew populations on the reserve are stable, contrary to the national trend, and lapwings have returned to the upland areas. Numbers of black grouse, whinchat and grasshopper warbler have also increased on the reserve, all showing the benefits of allowing sphagnum ecosystems to regenerate.

References

 ¹ Natural England. 2014. IPENS 055 Burning in the English Uplands - A Review, Reconciliation and Comparison of Results of Natural England’s Burn Monitoring: 2005-2014

² Douglas, D.J.T., Buchanan, G.M., Thompson, P., Amar, A., Fielding, D.A., Redpath, S.M. & Wilson, J.D. 2015. Vegetation burning for game management in the UK uplands is increasing and overlaps spatially with soil carbon and protected areas. Biological Conservation 191, 243-250

³ https://www.rspb.org.uk/our-work/our-positions-and-casework/casework/cases/walshaw-moor/

⁴ Carbon Trust conversion factors: -

https://www.carbontrust.com/resources/guides/carbon-footprinting-and-reporting/conversion-factors/

⁵ England’s peatlands: Carbon storage and greenhouse gases. Natural England (2010)

⁶ Natural England. 2013. The Effects of Managed Burning on Upland Peatland Biodiversity, Carbon and Water. Natural England Evidence Review 004

⁷ UK Government Report (Article 17 Habitats Directive) - http://cdr.eionet.europa.eu/Converters/run_conversion?file=gb/eu/art17/envxuwt7a/GB_habitats_reports-20190815-092118.xml&conv=589&source=remote#7130