Development of a Methodology to Summarise and Track Air Pollution Effects on Ecosystems at Regional Scales

January 2010

Background to research

Defra and the Devolved Administrations are responsible for an air quality classification scheme that assesses the impacts of air quality on human health, as well as a number of long-term air quality indicators. The classification scheme has two key functions: it provides information on the status of air quality based on near-real time information; and it feeds into one of the UK Government‟s headline air quality indicators for sustainable development. The indicators assess the progress of measured and modelled air pollution levels against specified health based targets.

Environmental regulators within the UK are responsible for not only impacts on human health but also for protecting the environment as a whole – including ecosystems and civil amenities. It is therefore recognised by these organisations that there would be benefits in developing a suitable methodology that could summarise all of the various negative effects of air pollutants: human health, ecosystems, and amenities.

A previous SNIFFER project, UKPIR03 “Extension of the UK Air Quality Classification Scheme: Scoping of Options”, investigated the feasibility of extending the health-based scheme to integrate ecosystem and civil amenity measures to provide a new tool for the management of air quality. The study also considered how a scheme could be tailored for use at a local and regional scale. The report recommended that any future work should focus, in the first instance, on the development of a classification system based on assessing ecosystem impacts.

Objectives of research
This project aims to fulfil the recommendations of this previous study by developing an appropriate methodology and set of indicators that can be used to identify and summarise the impacts of air pollutants on ecosystems. The key objectives are to provide a methodology which:

  1. Identifies the effects of air pollution on the ecosystem(s) under scrutiny;
  2. Identifies the potential sources of air pollutants affecting the ecosystem(s) under scrutiny;
  3. Facilitates long-term trend monitoring and analysis of the effects of air pollution on ecosystems so that the success (or otherwise) of regulatory measures can be assessed;
  4. Assists regulators (or other relevant bodies) to determine annual air pollution improvement targets or identify issues of concern requiring improvement;
  5. Provides the public with a simple, easily understandable and user-friendly means of assessing air pollution effects on ecosystems of interest.

In addition, there is a need to consider how the methodology can be applied across a range of spatial scales to allow for national and regional interrogation of data.

Key findings and recommendations
The full suggested methodology is split into three tiers of classification. Tier 1 uses existing critical load and critical level data to determine the level of risk to assign to each 1km x 1km grid square throughout the UK. Tier 2 enables a further classification of those areas deemed to be at risk where sufficient information exists and where such further classification is deemed to be valuable to the user. Tier 3, the final tier, provides a validation strategy to reduce the uncertainty of the assigned risk through the quantification of impacts. These Tiers are summarised below along with the key outputs.

  Description Key Outputs
Tier 1 Use of critical loads and critical levels to assign each 1km grid square a risk level of GREEN, AMBER or RED
  • A map of the UK showing worst-case risk from air pollution at a 1km x 1km resolution.
  • An underlying database to allow a summary of risk at a regional level and for different pollutant-habitat combinations
  • A starting point from which to focus more detailed classification.
Tier 2 Further classification of AMBER and RED risk into Level 1 to Level 4 to facilitate summary of regional impacts
  • More detail for defined geographical areas
  • The finer classification allows for more detailed long-term monitoring of risk status
  • A database of all at-risk habitats (optional)
Tier 3 Validation and reduction of uncertainty.
  • Evidence to confirm or refute the assigned risk categories· Focus funding and effort
  • Use of a standard set of bio-monitoring techniques to monitor site changes and compare sites regionally

The availability, periodicity and quality of data that could feed into the proposed methodology are identified and discussed.

In order to fully investigate the feasibility of developing the methodology discussed within this report, the implementation of a testing phase is considered. A demonstration area around Sheffield is recommended based on the presence of a Special Area of Conservation (SAC) and a large urban area in close proximity. This would serve to demonstrate the methodology within both comparatively data rich and data poor areas.

Key words: air pollution, air quality, bio-indicator, classification scheme, critical level, critical load, ecosystem, habitat, indicator, pollution, regional scale, risk-based methodology, risk-based approach

Copies of this report are available from the Foundation, in electronic format on CDRom at £20.00 + VAT or hard copy at £25.00, less 20% to FWR members.

N.B. The report is available for download from the SNIFFER Website