This paper highlights the contribution of the scientific work within ELOISE to the understanding of the ecological functioning of coastal ecosystems under eutrophication stress and what the implications are for the management of these systems.
Our main objectives were (i) to identify the cross-cutting concepts emerging from the scientific studies, (ii) to point out how these concepts changed our view of the intrinsic characteristics of ecosystems and of their responses to man-made disturbance, and (iii) to relate them to issues in ecosystem management. One important conclusion is the crucial issue of spatial and temporal scale for most of the processes controlling the fluxes and impacts of nutrients in water systems. Beside the availability of the appropriate models and databases, necessary tools to bridge the gaps between scales, the main challenge for water systems managers is how to organize a system where appropriate and coordinated actions can be taken at all scales, from local communities to the European level. This study points out some tremendous advances in our understanding of essential processes in nutrient cycling that are triggered by progresses in fundamental scientific knowledge. It follows that continuing efforts at deepening our insight into ecosystem functioning are required to support a sound management for coastal ecosystems.