Trade-offs in ecosystem services under various river management strategies of the Rhine Branches

To make river basins more climate resilient, provide a better living environment for people and other organisms, the EU encourages integrated river and floodplain management (RFM) and calls for restoration of 25,000 km of EU rivers to a free-flowing state in the EU Nature Restoration Law. To support decision making in this domain, there is a need for a holistic assessment framework. However, most policy appraisal studies in river management to date have a limited scope and focus on impacts of measures in a single domain, such as flood risk reduction or water quality. In this study we address this gap by using quantitative models to analyse the supply of 13 ecosystem services under various RFM strategies for the Rhine Branches in the Netherlands. We use a mix of biophysical and monetary indicators to quantitatively assess ecosystem services and the trade-offs involved in different RFM strategies. The results show that strongly regulated, mono-functional RFM has overall lower ES supply than more integrated, multifunctional RFM strategies with rehabilitated floodplains. The latter generally increase ES supply across all domains (provisioning, regulating, cultural), with the exception of crop and fodder production in the floodplains. Overall, our results can inform formulation and communication on RFM strategies in the Netherlands and elsewhere. Also, our approach serves as a demonstration of how the ES framework can be used to support quantitative impact assessment in this domain.