Recovery of the Red Forest from a fire event

Severe and acute radiation from the Chernobyl accident killed coniferous trees in a 4-6 km2 area of forest, now known as the ‘Red Forest’. In July 2016, an accidental fire burnt c.80% of this area presenting a unique opportunity to study the effect of fire on radionuclide biogeochemistry and the impact of radiation on the recovery of forest ecosystems exposed to a secondary stressor (fire). The RED FIRE project built upon pre-fire baseline measurements collected by the TREE project and data from collaborating Ukrainian scientists; this gave us an opportunity to contrast pre- versus post-fire ecosystem states. The objectives of the project were to assess the impact of fire on radionuclide mobility in soil and determine if there was any impact of radiation on the recovery of the forest ecosystem. To achieve these objectives we used some approaches novel to radioecology: bait lamina sticks to measure soil biological activity; aerial drone vegetation and contamination mapping; wildlife camera traps and bioacoustic recorders. This poster concentrates on our studies of the recovery of vegetation and soil biological activity following the fire. In April 2016 (pre-fire), we deployed bait lamina sticks at 18 sites in the Chernobyl Exclusion Zone (11 in the Red Forest) to investigate soil biological activity across a range of ambient dose rates (13-220 μSvh-1). The bait lamina sticks are 10 cm long PVC strips with 16 small holes along their length; the holes are filled with bait (food); loss of bait provides a measure of soil biological activity. In September 2016, to assess ecosystem recovery post-fire, we deployed bait lamina at 20 sites in the Red Forest, including the 11 sites previously used in April 2016; they were re-deployed in spring and autumn 2017. A summary of the results from these studies are presented. In September 2016, at each of the 18 bait lamina sites, vegetation cover was recorded using photographs. Sites were marked so that subsequent vegetation recovery could be monitored using photographs and by an on-ground vegetation survey; species present at each plot were identified and the percentage cover was recorded in September 2017. In March 2017, aerial drone flights were also used to provide a photogrammetric analysis of vegetation cover; the area will be reflown in summer 2018. A summary of the results from these studies is also presented. Acknowledgements: RED FIRE (https://www.ceh.ac.uk/redfire) was funded under a NERC Urgency Grant (NE/P015212/1). Deployment of the camera traps was conducted as part of the TREE project (http://www.ceh.ac.uk/tree) which is co-funded by the Natural Environmental Research Council, Environment Agency and Radioactive Waste Management Ltd.