Air Pollution Recovery Indicators - Assessing potential indicators of recovery from air pollution through monitoring air quality and ecological parameters at Skipwith Common SAC

Overview

Project Aims • Assess whether there has been ecological recovery at Skipwith Common SAC following the closure of nearby coal-fired power stations, by monitoring air quality, vegetation, and soil parameters. • Replicate and enhance previous surveys (from 2011 and 2014) to detect changes in atmospheric pollutants (NH₃, SO₂, NOₓ), vegetation communities, and soil chemistry. • Develop robust, repeatable monitoring methods to track recovery indicators and provide a platform for future long-term monitoring. • Generate evidence to inform site management and national policy and provide recommendations for extending recovery assessments to other sites. Project Background The Large Plant Combustion Directive (LPCD), introduced by the European Union, aimed to reduce air pollution from large combustion plants by setting limits on emissions of sulphur dioxide (SO₂), nitrogen oxides (NOₓ), and particulate matter. As part of compliance, UK power stations were required to monitor ecological impacts at nearby Natura 2000 sites. UKCEH conducted a four-year monitoring programme (2011-2015) across seven sites, including Skipwith Common in North Yorkshire, which was notably affected by emissions from three nearby coal-fired power stations: Drax, Eggborough, and Ferrybridge. See figure1. Skipwith Common National Nature Reserve (NNR) spans 270 hectares was selected for its representative heathland vegetation, minimal land management, and proximity to existing monitoring infrastructure. The original study involved air quality measurements, vegetation surveys, and soil analyses. With the closure of the three power stations and reduced pollution levels suggested by regional data, this contract seeks to revisit the site to assess signs of ecological recovery. This includes evaluating changes in air quality, vegetation composition, and soil chemistry, building on the baseline data collected over a decade ago. Figure 1: Location of Skipwith Common (red point) and the three former coal-powered power stations (yellow points) This contract forms part of the Air Pollution Recovery Indicators programme of work. Project Objectives To meet the overall aims of this project (Section 0), the objectives are: To assess whether Skipwith Common SAC shows signs of ecological recovery from air pollution following the closure of nearby coal-fired power stations, by replicating and enhancing previous air quality, vegetation, and soil monitoring surveys. Project Objectives: Detailed Tasks Contractors are welcome to suggest their own sample placements, numbers and analysis. The below is just a suggestion based on previous work. • 12 months of air quality, vegetation, and soil monitoring at Skipwith Common SAC to detect signs of ecological recovery following the closure of nearby power stations. I. This could include monitoring of concentrations of NH₃, SO₂, and NOₓ (at least 10 locations) II. Utilise existing monitoring and data where possible e.g. wet deposition. III. Re-survey the original 50 quadrats (2x2 m) within the 1-hectare area using the same methodology as in 2011 and 2014 and record species presence and abundance to detect changes since 2014. IV. Estimate of soil chemistry across the site e.g. pH, nutrients and base cations V. Set up monthly soil solution sampling at 2 depths e.g. 15cm and 30cm and analyse for acid anions, base cations, pH, DOC, ammonium, phosphate, and conductivity. • Deploy a multi-parameter weather sensor to measure temperature, humidity, wind speed/direction, and pressure. • Install a solar radiation sensor to support dry deposition modelling. • Replicate and enhance previous surveys to enable direct comparison of current and past air pollution and ecological data. Compare 2025 findings with 2011 and 2014 data. • Develop and validate robust indicators and methodologies for tracking recovery from air pollution in heathland habitats. • Provide evidence and recommendations to inform site management, national policy, and potential extension of mon