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

1. Joint Nature Conservation Committee

The Joint Nature Conservation Committee (JNCC) is the statutory adviser to the UK Government and devolved administrations on UK and international nature conservation

Our role is to provide scientific evidence, information, and advice to inform decisions to protect the natural environment. Our specific role is to work on nature conservation issues that affect the UK as a whole and internationally, by:

• advising Government on the development and implementation of policies for, or affecting, nature conservation in the UK and internationally;
• providing advice and disseminating knowledge on nature conservation issues affecting the UK and internationally;
• establishing common standards throughout the UK for nature conservation, including monitoring, research, and the analysis of results; and
• commissioning or supporting research which it deems relevant to these functions.

Background to JNCC can be found on JNCC's website at: jncc.gov.uk/about-jncc/ ↗

2. 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.

3. 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.

4. Project Objectives

To meet the overall aims of this project (Section 2), 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.

5. 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 monitoring to other sites

6. Potential Follow-On Work

Bidders should be aware that there is the potential for the successful bidder to be requested by JNCC to undertake additional work on this contract into the financial year 2026/27. This could be for follow on work at other Energy Supply Industry sites (ESI's) subject to funding post March 2026.

Please note however that the potential for additional work to be undertaken is subject to a continuing need, availability of funds and satisfactory contractor performance. For the avoidance of doubt, no guarantee can be given that you will be asked to undertake the potential additional work outlined within this SoW document. Bidders are not asked to provide detailed project plans for these follow-on aspects at this stage.

7. Outputs

• A detailed report comparing current (2025) air quality, vegetation, and soil data with baseline surveys from 2011 and 2014.
• Assessment of ecological recovery indicators and identification of any changes in atmospheric pollutant levels and ecosystem health.
• Recommendations and lessons learned for extending similar monitoring and recovery assessments to other sites.
• Data and evidence to inform site management, policy decisions, and future monitoring strategies.

8. Product Specification

JNCC is committed to making its publicly available resources and documents accessible, in accordance with the Public Sector Bodies (Websites and Mobile Applications) (No. 2) Accessibility Regulations 2018.

Making material accessible means making sure it can be used by as many people as possible. This includes those with:

 impaired vision

 motor difficulties

 cognitive impairments or learning disabilities

 deafness or impaired hearing

The outputs and material that JNCC publishes should be compliant with the Web Content Accessibility Guidelines version 2.1 AA standard.

To meet this standard, all reports and other documentation which are to be made publicly available must adhere to JNCC's house-style (to be provided) and be produced using a JNCC template (to be provided), unless otherwise stated. (Project managers to note - there are two templates, please decide which is most appropriate, either the 'standard' template rather than the JNCC report template). All reports (draft and final) should be provided electronically via email both as a Microsoft Word document and an Adobe PDF.

Copies of documentation associated with case studies should be provided in electronic format with an associated reference catalogue.

For any other outputs or products which are to be made publicly available through JNCC, evidence regarding how the accessibility standard will be reached should be included.

(Note for author if research project/contract: see EQA Policy Appendix 4 (Communicating Evidence Quality). Ensure that data management and storage requirements are stipulated taking into account relevant policy for data access. See jncc.gov.uk/about-jncc/corporate… ↗