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A metric for assessing changes in biodiversity for the UK’s response to a data request under the Convention on Long-range Transboundary Air Pollution - AQ0832

Air pollution has harmful effects on UK habitats. Major reductions in emission and deposition of acidifying pollutants have been achieved, but habitats are still under threat from nitrogen (N) pollution. One of the major effects of N pollution is eutrophication, which increases the amounts of standing vegetation and plant litter, making habitats unsuitable for many species that are considered important for the integrity of the habitat. The effects of different N pollution scenarios on soil and vegetation, and thereby on habitat suitability for individual species, can be predicted with reasonable accuracy using soil-vegetation models. However, there has until recently been little consensus on how changes in the species composition of a habitat should be interpreted in terms of legislative targets, or in terms of more general concepts of habitat quality and damage.

In an initial study (AQ0828), habitat specialists at the Statutory Nature Conservation Bodies were consulted to canvas their views on how habitat quality should be assessed. This was done using a combination of qualitative methods (semi-structured interviews) and quantitative methods (ranking of a set of habitat examples). Although aspects such as the total number of species, or presence of structurally important species, were considered important, the clearest relationship with the specialists’ overall assessment of the quality of the examples was obtained by using habitat-specific sets of positive indicator-species. Such species have been partially defined for many habitats in ‘Common Standards Monitoring’ guidance, and there is ongoing work to revise these species lists for UK Priority Habitats.

The current project aims to build on the results of the initial study and fully develop habitat-specific metrics to inform the development of air pollution policy. Specifically, the UK is a Signatory Party to the UNECE Convention on Long R/’ange Transboundary Air Pollution, under which a ‘Call for Data’ has been issued which asks Signatory Parties to provide operationalised biodiversity metrics for use in this context. The project will develop metrics that can be used to interpret the outputs from soil-vegetation models, using worked examples from real sites. These metrics and examples will be used to prepare a response to the Call for Data.
The overall aim of the study is to fully develop metrics for interpreting the outputs from soil-vegetation models in terms of progress towards the objective of ‘no net loss of biodiversity’. Specific objectives are:
1. To select habitats and example sites to operationalise and illustrate the metrics, discuss this selection with Defra, and finalise the list of sites on 14th February 2014.
2. To set up the MADOC-MultiMOVE soil-vegetation model for these sites, by calibrating to current conditions as indicated by abiotic measurements and/or the floristic composition.
3. To run the model forward to 2100 under N emissions scenarios provided by the CCE.
4. To develop methods for calculating habitat-specific summary metrics from model outputs.
5. To calculate these metrics for the example sites under the scenarios provided, and make a first submission to CCE in the Call for Data template, including a 10-page report on methods, on 3rd March 2014.
6. To describe and justify the approach in a 20-page report to Defra and in a “UK Status Report” chapter for the 2014 CCE Status Report, with drafts to be submitted on 28th March and 15th April and a final version on 9th May.
7. To further develop these metrics and make a second submission to CCE in the Call for Data template, on 9th May 2014.
8. To further publicise and disseminate the project and its conclusions.
Dependencies are illustrated in a chart, submitted separately in the file "AQ0828 DivMet followup - dependencies and GANTT chart.docx"
Project Documents
• FRP - Final Report : Final report - AQ0832 Operationalising a metric of nitrogen impacts on biodiversity for the UK response to a data request from the Coordination Centre for Effects   (622k)
Time-Scale and Cost
From: 2014

To: 2014

Cost: £29,667
Contractor / Funded Organisations
Centre For Ecology and Hydrology (CEH)
Air Quality              
Fields of Study
Air Quality