Making the ecosystem services approach operational: A case study application to the Aarhus River, Denmark.

The ecosystem services (ESS) approach seeks to identify and characterize links between ecosystems and human welfare. The DESSIN ESS evaluation framework is a novel methodology that has been developed to operationalize ecosystem service assessment, with a focus on urban freshwater settings. This paper describes an application of the framework to a retrospective case study in Aarhus, Denmark, which was used to test the framework and make suggestions for improvement. River restoration and wastewater management measures enhanced ecosystem state and the provision and use of purification and recreation ESS for selected beneficiaries, including increased economic values. Feedback from this case study suggests a missing link between science-based ESS approaches, which often have a normative basis in ecosystem status, and the real-world provision and use of ESS in urban settings. In the urban context, many ESS result from a combination of human and ecosystem inputs, and the human inputs can often be significant. Quantifying ESS provision and use therefore requires understanding how ecosystem and human inputs work together to make contributions to human welfare.