Using ecosystem services to inform decisions on U.S. air quality standards.

The ecosystem services (ES) framework provides a link between changes in a natural system's structure and function and public welfare. This systematic integration of ecology and economics allows for more consistency and transparency in environmental decision making by enabling valuation of nature's goods and services in a manner that is understood by the public. This policy analysis (1) assesses the utility of the ES conceptual framework in the context of setting a secondary National Ambient Air Quality Standard (NAAQS), (2) describes how economic valuation was used to summarize changes in ES affected by NOx and SOx in the review, and (3) uses the secondary NOxSOx NAAQS review as a case study to highlight the advantages and challenges of quantifying air pollutant effects on ES in a decision making context. Using an ES framework can benefit the decision making process by accounting for environmental, ecological, and social elements in a holistic manner. As formal quantitative linkages are developed between ecosystem structure and function and ES, this framework will increasingly allow for a clearer, more transparent link between changes in air quality and public welfare.