• nitrogen;
  • ammonia;
  • economic valuation;
  • ecosystem service;
  • air pollution;
  • biodiversity;
  • climate regulation


To date evaluation of the benefits of policies to control emissions of air pollutants in the UK has focused on human health effects, which are quantified economically, whereas ecosystem protection has been assessed using critical levels and critical loads. This paper considers the current feasibility of using an ecosystem services approach to appraise the benefits of alternative scenarios for controlling agricultural ammonia emissions in the UK. The effect of ammonia emission reductions on ecosystem service delivery was assessed using an impact pathway approach. A ‘weakest link’ analysis identified that economic valuation of impacts on many key ecosystem services was constrained by inadequate dose–response relationships to predict physical changes in service flows and/or by an inability to produce economic valuations of the predicted physical changes. For effects on biodiversity, both the timescale of response and poorly defined relationships between changes in species composition and ecosystem service delivery are significant barriers. However, it was possible to produce indicative values for the marginal impact of ammonia abatement measures on climate regulation; the values obtained were comparable in magnitude to those for human health impacts. The ecosystem service approach thus offers the potential to provide a holistic appraisal of the effects of emission reductions, and could therefore make a valuable contribution to future air quality management. However, improvements in data collection and quantification methods are needed before a full ecosystem services-based evaluation of costs and benefits becomes possible for ammonia and for other major air pollutants. Copyright © 2011 John Wiley & Sons, Ltd.