Monitoring peatland using Earth observation data
By Anna Robinson
Monitoring of peatland condition has traditionally relied on ground-based surveys; however, some of our recent work suggests that Earth observation may provide a cost-effective dynamic method for large-scale assessment of peatland habitats.
The value of peatlands
In the UK, peatland covers over 10% of the land surface, but worryingly 80% of this is thought to be in damaged condition, due to threats such as drainage, extraction, burning and overgrazing (Bain et al. 2011; IUCN 2018). Why is this of such concern? Whilst peatlands don’t tend to capture the public imagination like tropical rainforests or flower rich meadows, they are still highly important and influential habitats. Peatlands provide essential ecosystem services such as climate regulation, water purification and flood prevention, as well as being vital ecosystems which provide habitat for nationally and internationally important species (FAO 2020).
What’s more, the condition of peatland has a direct impact on how well it can provide these important ecosystem services. For example, a peatland in a healthy condition helps regulate climate by acting as a carbon sink and removing the greenhouse gas carbon dioxide out of the atmosphere, as it naturally lays down more peat in a deepening layer. In a degraded peatland habitat, the peat becomes eroded and acts as a carbon source, releasing carbon dioxide back into the atmosphere, contributing to greenhouse gas emissions and climate change.
Taking this on board, it’s not surprising that peatlands feature highly in the conservation policies of the UK and its component countries, including in the UK Peatland Strategy, Scotland’s National Peatland Plan, Wales’ Peatlands for the Future, Defra’s 25 Year Environment Plan and Northern Ireland's peatland policy statement. Monitoring peatland extent and condition is critical – helping to keep tabs on the situation, know when and where is best to target conservation interventions, and to help evaluate the success of the restoration measures.
How has JNCC been involved in supporting peatland conservation?
As an organisation we don’t get involved in the practical implementation of conservation measures – that’s the role of the country nature conservation bodies in the UK. However, we do help to advise UK governments on conservation science issues, and look to provide cross-cutting support and join up across the UK through various means. We particularly look out for opportunities where we can make a difference and improve cost effectiveness, for example by exploring novel techniques and developing new methods ready for use across the four countries.
Since 2011, JNCC has been working with others to make the most of the potential for using Earth observation (EO) imagery from satellites to provide a quicker more cost-effective means of monitoring priority habitats such as peatland. In 2014, the European Copernicus space programme launched its first sentinel satellites, followed by satellites recording high-resolution optical imagery in 2015 and 2017. As a result, both the amount of EO data available and the resolution of the data, were increasing, and we wanted to make the most of it.
Defra EO Centre of Excellence
In 2015, JNCC became a key player in the new Defra EO Centre of Excellence (CoE) – set up to enable people from science and delivery bodies to work together, share best practice and facilitate the use of EO data in an operational environmental context. Our experts supported a number of EO CoE projects, including one initiated in 2016/17 specifically focussing on the use of EO to monitor peatlands. This Defra CoE and Scottish Government co-funded project looked into how Earth observation might provide a cost-effective method for large-scale assessment of peatland condition, with research being carried out by the UK Centre for Ecology & Hydrology and the James Hutton Institute. The resulting report describes the potential of freely available EO data to map and monitor the condition of the UK’s peatlands, linking this to impacts on greenhouse gas regulation.
The EO CoE project showed considerable potential and we decided to investigate it further, by exploring how different types of remote sensing data could be used to help monitor peatland condition at different scales. Our next project investigated the use of very-high resolution (VHR) imagery to create fine-scale maps of bare peat, a visual indicator of peatlands in poor condition. We then explored the best process to use to scale this up to predict bare peat across a wider region, using regression modelling with Sentinel-2 satellite imagery. The findings confirmed how this type of analysis can indicate where areas of peatland are in poor condition, whilst noting recommendations for improving the approach.
Following on from this, we partnered with Natural England, Welsh Government and Forest Research under a Copernicus User Uptake project as part of the Caroline Herschel Framework Partnership Agreement, to further explore how such methods and models could be used to detect changes in peatland condition over time. This project focussed on four peatland sites, covering upland and lowland sites across England, Scotland and Wales. The project was successful in demonstrating how changes over time could be identified using a time-series of Sentinel-2 imagery, as well as noting factors that could improve the accuracy of predictions. Through working with site experts, we were able to gain insights into interpreting and evaluating the approach – noting specific site nuances that influenced results (e.g. localised site flooding). The report highlighted that further methods could be explored to help take account of such issues and improve the approach, but overall we were encouraged by a lot of positive feedback from field staff on the potential of the methods to support and inform site management and evaluation, and to guide where best to target restoration measures.
Sharing the knowledge
Noting that conservation of peatlands is of global interest, we are keen to share our knowledge and understanding and collaborate more widely with the scientific community, both in the UK and beyond.
In December 2020, the International Union for Conservation and Nature (IUCN) held their 10th annual UK Peatland Programme Conference online, with the focus being to turning peatland strategy into action. The conference 'explored the vital role that healthy peatlands play in society's adaptability, resilience and recovery and shared progress made towards UK Peatland Strategy goals', whilst welcoming international speakers and delegates from across the globe. At this event analyst Becky Trippier, and habitat and EO specialist Paul Robinson presented JNCC’s recent work from the Copernicus User Uptake project, whilst JNCC’s international biodiversity advisor Stephen Grady presented an overview of the UK’s approach to assessing the conservation status of rare, threatened or endemic habitats, animals and plants in the context of peatland ecosystems. Becky and Paul also took part in a Q&A session alongside other scientists who discussed the methods for integrating remote sensing and ground surveys to assess peatland condition.
With the increasing focus on climate change and managing greenhouse gas emissions, in conjunction with the ongoing biodiversity crisis, the conservation of peatlands is now seen as being more important than ever. Having a better understanding of peatland condition and how it is changing is seen as critically important in helping us assess the overall status of the habitat and the ecosystem services it provides. It can also help us to understand where to target restoration measures, and to assess their effectiveness, leading to better and more sustainable land management decisions.
Our recent work highlights the potential role Earth observation data can play in providing a cost-effective means of monitoring peatland condition on a wide scale, and in facilitating targeted restoration efforts to support peatland recovery, carbon capture, and net-zero emissions goals across the UK.
Here at JNCC, we are pleased that the EO expertise and analytical capacity we have been developing over the last decade is really starting to help address practical conservation issues, and are looking forward to what we might tackle next.
Bain, C.G., Bonn, A., Stoneman, R., Chapman, S., Coupar, A., Evans, M., Gearey, B., Howat, M., Joosten, H., Keenleyside, C., Labadz, J., Lindsay, R., Littlewood, N., Lunt, P., Miller, C.J., Moxey, A., Orr, H., Reed, M., Smith, P., Swales, V., Thompson, D.B.A., Thompson, P.S., Van de Noort, R., Wilson, J.D. & Worrall, F. (2011) IUCN UK Commission of Inquiry on Peatlands. IUCN UK Peatland Programme, Edinburgh.
FAO (2020) Peatlands mapping and monitoring – Recommendations and technical overview. Rome. https://doi.org/10.4060/ca8200en
The International Union for the Conservation of Nature (IUCN). 2018. UK Peatland Strategy 2018-2040. IUCN UK Peatland Programme, Edinburgh. Available from: https://portals.iucn.org/library/sites/library/files/documents/2018-015-En.pdf [Accessed 07/07/2020].
Image credits: Golden plover © Anna Robinson; Sundew on sphagnum © Rebekah Robinson; Mapping process infographic produced by Becky Trippier, using data from Getmapping Plc and Bluesky International Limited , and ESA, 2020 Sentinel-2 imagery.