Prescribed burning not as damaging as previously thought

December 03, 2018

New research by the University of Liverpool has found that prescribed burning, a controversial technique where fires are intentionally used to manage vegetation, is not as damaging to peat growth as previously thought if carried out on a sensible rotation, and can produce several positive outcomes.

In a study published in Nature Geoscience, scientists analysed data from a long-term ecological experiment at Moor House National Nature Reserve which contained areas of moorland that only been burned in 1954, or since 1954 had burned either every ten or every twenty years. These were compared with "control" areas unburned since the 1920s.

Analysis of changes in vegetation composition, led by Emeritus Professor Rob Marrs from the University's Department of Earth, Oceans & Ecological Sciences, found that the areas which hadn't been subjected to any prescribed burns were dominated by heather, and other low-level, peat-forming species, and contained less good peat-forming species such as Sphagnum mosses and cotton grasses.

New stratigraphical data collected on the rate of peat and carbon accumulation led by Professor Richard Chiverrell from the University's Department of Geography & Planning measured numerous peat profiles sampled from the different prescribed burn areas.

Professor Chiverrell said:" This is first time that stratigraphical techniques have been used within the structure of a designed experiment. Our data show only limited reduction of peat and carbon accumulation with increased burning treatments. Crucially, there was continued peat and carbon accumulation even in the areas that had undergone the regime of most frequent burning."

The researchers also modelled the effects of these experimental prescribed burning treatments on potential damage caused by severe wildfires, and predicted that prescribed burning on rotation in some areas would reduce fire fuel loads (the amount of flammable material available to be burned in a fire), protect against more severe ecosystem damage, allow better access for fighting wildfires and promote faster recovery post-wildfire.

Prescribed burning is a technique used throughout the world however its use, especially on peatlands in Britain, is contentious. It has been thought by many involved in peatland conservation that prescribed burning stops peat growth, reduces carbon capture, increases coloration in water and reduces the amount of peat-forming species especially Sphagnum mosses and cotton grass.

Emeritus Professor Rob Marrs said: "The research, which was truly interdisciplinary and combined several scientific approaches, centred on a long-term, replicated experiment at Moor House National Nature Reserve. As part of that experiment the moorland was subjected to four burning treatments to determine the change in composition of the main species. The value of long-term experiments is that they allow new hypotheses can be tested which were unforeseen at the start,

"Our study produced surprising results that are the opposite of what many conservationists had previously thought. It showed that the areas which had not been burnt since 1954 ended up with more heather and less peat forming species but the most frequently burned treatment had more of these species and did not stop carbon accumulation. We advise that prescribed burning be used in some areas within a moorland management plan to minimize fuel loads.

"This work is unique because it uses stratigraphical methods, usually used to measure change over millennia, to assess recent environmental changes within a relatively long-term manipulative field experiment."
-end-
The paper `Experimental evidence for sustained carbon sequestration in fire-managed, peat moorlands' is published on 3rd December 2018 in Nature Geoscience (doi: 10.1038/s41561-018-0266-6. or weblink: http://dx.doi.org/10.1038/s41561-018-0266-6)

Notes to editors:

  1. The University of Liverpool is one of the UK's leading research institutions with an annual turnover of £523 million. It is a member of the Russell Group. Visit http://www.liv.ac.uk or follow us on twitter at: http://www.twitter.com/livuninews
  2. Moor House National Nature Reserve is run under the Centre for Ecology & Hydrology's Environmental Change Network (NERC's National Capability), and is included in the inventory of important experiments on the Ecological Continuity Trust's register.
  3. Calibration of the changes in lead concentrations to a time scale was performed by Emeritus Professor Peter Appleby and Dr Gayane Piliposyan from the University's Environmental Radioactivity Research Centre.
  4. The work was made possible by the Geotek Multi-Sensor Core Logging and Near Infrared Spectrometry facilities available within the University's Central Teaching Laboratories, alongside specialist Energy Dispersive X-ray Florescence (Spectro XEPOS ED-XRF) in the Environment Change laboratories.
  5. Postgraduate students on Masters Programmes (MSc in Climate and Environmental Change and MSc Environmental Science) in the University's School of Environmental Science contributed to the research.
  6. The work was part funded by a BioDiversa grant (NERC/DEFRA, NE/G002096/1) and the Heather Trust (whose small grant funded the radiometric measurements).


University of Liverpool

Related Peat Articles from Brightsurf:

Carbon-releasing 'zombie fires' in peatlands could be dampened by new findings
New simulations have provided clues on reducing uncontrolled peat fires, which hide underground and are notoriously bad for human health and the environment.

Study finds seabird ecosystem shift in Falkland islands
The 14,000-year-old record raises a very troubling question about where seabirds in the South Atlantic and Southern Ocean will go as the climate continues to warm.

Where will the seabirds go?
A new study of a 14,000-year record, published in Science Advances, shows that seabird poop transformed an entire ecosystem in the Falkland Islands, raising questions about the birds' survival and the potential impact of climate change on sensitive terrestrial-marine ecosystems

Indonesia's old and deep peatlands offer an archive of environmental changes
Researchers probing peatlands to discover clues about past environments and carbon stocks on land have identified peatland on Borneo that is twice as old and much deeper than previously thought.

Carbon storage from the lab
Researchers at the University of Freiburg established the world's largest collection of moss species for the peat industry and science

Enforcement more effective than financial incentives in reducing harmful peat fires?
A new study looking at incentives to reduce globally harmful peatland fires suggests that fear of enforcement and public health concerns influence behaviour more than the promise of financial rewards.

Bering Sea ice extent is at most reduced state in last 5,500 years 
Through the analysis of vegetation from a Bering Sea island, researchers have determined that the extent of sea ice in the region is lower than it's been for thousands of years.

Oil spill clean- up gets doggone hairy
A study investigating sustainable-origin sorbent materials to clean up oil spill disasters has made a surprising discovery.

Low-severity fires enhance long-term carbon retention of peatlands
High-intensity fires can destroy marshy peatlands and cause them to emit huge amounts of their stored carbon into the atmosphere as greenhouse gases, but a new Duke University study finds low-severity fires spark the opposite outcome.

Lacustrine ecosystems needed 10 million years to recover after end-permian mass extinction
A research team led by Prof. WANG Bo from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NIGPAS) found that both lake and peat-forming forest ecosystems probably took as long as 10 million years to recover after the end-Permian mass extinction.

Read More: Peat News and Peat Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.