TP18 Assessing Ecosystem Services and Benefits
Tuesday, 15 November 2005: 8:00 AM - 6:30 PM in Exhibit Hall

(BRU-1116-603512) Expanded conceptual models as an organizing framework for ecological benefits assessment.

Bruins, R¹, Heberling, M¹, ¹ U.S. Environmental Protection Agency, Cincinnati, OH, USA

ABSTRACT- The conceptual models that typically are used to organize ecological risk assessments are diagrammatic depictions of risk hypotheses — proposed explanations of relationships between sources, stressors, exposure pathways, and effects on ecological assessment endpoints. To assess ecological benefits, risk hypotheses must be expanded to include the changes in ecosystem services that will be associated with the changes in those endpoints. Further, since the evaluation of management alternatives (such as project alternatives for a local stream restoration or options for a national regulation) usually is the goal of benefits assessment, risk management hypotheses are needed as well. These are proposed explanations of how management alternatives will affect sources, exposures, effects and services. We show how expanded conceptual models may be used both to guide technical evaluation of alternatives and as a communication tool, helping stakeholders appreciate the relative merits of management and restoration alternatives, both in terms of the costs of those actions and their expected ecological benefits.

Key words: ecological risk assessment, ecosystem services, economics, risk management