Abstract
In the UK the major source of ammonia is from agriculture, which contributes about 80% of UK emissions to the atmosphere, primarily from livestock, manure/slurry management and fertiliser use. Ammonia can have a range of impacts on the environment and human health, including : - Effects on human health, due to ammonia induced formation of particulate matter and smog; - Plant damage through high ammonia concentrations near point sources; - Decrease of species diversity of semi-natural areas due to nitrogen enrichment through atmospheric nirogen deposition, especially ammonia and ammonium; - Acidification of soils through transformation of deposited ammonia to nitrate and its subsequent leaching; - Pollution of ground water and drinking water due to nitrate leaching; - Eutrophication of surface waters due to nitrogen enrichment; - Global warming due to emission of nitrous oxide and methane, and cooling due to ammonium sulphate aerosols; Air quality management for ecosystem protection has primarily focussed to date on the use of critical levels and critical loads to define environmental thresholds above which adverse effects may occur. However, the effects on ecosystem services of exceedance of these thresholds have not been fully evaluated. Furthermore, the nature of ammonia emissions and their diffuse sources make analysis of control measures and policies particularly challenging, and means that a policy approach which considers these ecosystem impacts in isolation is not viable. The additional complexity arises from the way nitrogen derived from ammonia emissions ‘cascades’ through the environment undergoing transformations that create potential for interactions between losses of nitrogen compounds to air and water from terrestrial systems - so called “pollution swapping”. For example, techniques to reduce ammonia emissions from the soil to air could potentially lead to the nitrogen emerging as nitrates in water courses to the detriment of the aquatic environment or to nitrous oxide emissions that contribute to climate change. In the UK to date, most effort has been placed in quantifying ammonia emission fluxes and investigating abatement strategies at the national scale. The Gothenburg Protocol of the United Nations Economic Commission for Europe and the EU National Emissions Ceilings Directive (NECD) commit the UK to a national target of ammonia emissions for 2010. Defra’s emission projections indicate that although the UK is likely to meet the 2010 target a lot more needs to be done to protect the environment and human health and meet the potentially tighter NECD emisison ceilings planned for 2020, forthcoming revisions of the Gothenburg Protocal and the requirements of other policy levers and controls such as the Catchment Sensitive Farming Programme under the Water Framework Directive and the Nitrates Directive. In view of the complex interaction of the various effects a truly integrated assessment of the ammonia problem is required to feed into the policy appraisal process. In line with this need, the UK government has committed itself to embedding the ecosystems approach in existing policy/ regulatory frameworks, which focus on human well being and providing value for money. An Ecosystems Services approach, based on the work of the Millennium Ecosystem Assessment (MA) and others may provide important advantages over existing integrated assessment systems as it offers: (i) a holistic assessment that considers the whole range of ecosystem services as a starting point; (ii) inclusion of regulatory services, such as ecosystem controls on fluxes of pollutants in land-water- air systems, which are currently under represented on UK policy; (iii) identification of ancillary benefits and trade offs of policy measures; (iv) insight into the true costs of policy measures. This project will compare the ecosystems approach with current conventional air quality management approaches to determine which assesses ecosystem services more comprehensively in terms of impacts, value of ecosytem services and links to human well-being. This will acheived by comparing three different approaches to emission control which involve different types of potential for 'pollution swapping'. The project will also identify potential barriers, and their causes, to the implementation of an ecosystems approach for air quality policy development at national level in the UK. A stakeholder workshop will be held to evaluate the implications of the new approach, to identify possible solutions to the barriers, and to identify how an ecosystems approach could be implemented within current and future policy frameworks.
United Kingdom