How does land management influence FIre REsilience and carbon fate in BLANKET bogs? (FIRE BLANKET)

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In good condition, peatlands are the most efficient soil carbon store, regulate freshwater and climate, and maintain biodiversity. However, management interventions can jeopardise the delivery of all these services by destabilising the vast C store that peat has locked away over thousands of years. In the UK, up to 80% of UK peatlands are damaged and release carbon back to the atmosphere as greenhouse gases like CO2 and methane, which amplify climate change in the same way that fossil fuels do. Furthermore, destabilisation of the peat carbon store can alter the flow and the quality of water within the peatlands and into streams, rivers and all the way to the sea. This can affect drinking water supplies as well as freshwater and marine habitats and wildlife. Importantly, disturbed peatlands may also become more vulnerable to stress, including severe drought and wildfires - events which are predicted to increase with future climate change.Understanding how land-use interacts with climate extremes in peatlands is essential to inform which management practices are likely to best maintain and enhance peatland carbon storage. However, this is notoriously challenging to achieve. Indeed, climate extremes are rare and ephemeral by nature, and therefore can only be opportunistically studied. In addition, their effects can only be truly assessed where high-quality ground-based observations pre-date a given extreme event, and where data from both impacted and similar control areas can be compared afterwards. These conditions rarely come together, but when they do, they provide unique opportunities. Following a dry and warm spring, in mid-May 2019, a large wildfire burnt approximately >60 km2 within the Flow Country peatlands of Caithness and Sutherland, North Scotland. Covering 4000km2, the Flow Country is a site of global significance currently under consideration for UNESCO World Heritage Site status. Nevertheless, it has also been substantially modified in places by drainage and notably forestry (with non-native conifer trees), making those areas particularly vulnerable to catastrophic deep burning. Unlike other wildfires in the UK, the May 2019 Flow Country fire covers an exceptionally large area that includes peatlands in a range of conditions: drained, drained and afforested, under restoration (through forestry removal and drain blocking) and near-natural. These areas are also actively used for scientific research, with a wide range of prior data and a mature collaborative network of researchers and land managers currently in place. The May Flow Country fire has therefore created an unprecedented and urgent opportunity to quantify the interacting effects of fire, drought and past human interventions on peatland carbon storage and water quality.We want to seize this opportunity. First, we want to compare burn severity, carbon losses during the fire, and initial recovery across the different peatland management types. To do that, we will combine ground measurements, UAV images and a newly validated method that uses satellite radar data to measure peat surface motion. This method works because the peat surface motion is a direct response to water storage in the peat, and the type of plants on the peat surface. These in turn are the main indicators of peat condition. By comparing data in the periods prior to and after the wildfire, we can examine the ability of peatland to recover from such an event. Secondly, we will measure aqueous and gaseous carbon emissions across a range of burnt and unburnt land-uses and we will quantify changes in the quantity and quality of dissolved organic matter, in order to understand how changes attributed to the fire alter the fate of peatland C. Finally, we will use our new knowledge and consult with land managers to compare how different management strategies of forestry and forest-to-bog restoration influence fire risk and damage in order to make recommendations for management and policy.