Towards answering the “so what” question in marine renewables environmental impact assessment

• Main Authors: Degraer, Steven, Birchenough, Silvana, Braeckman, Ulrike, Coolen, Joop W.P., Dannheim, Jennifer, De Mesel, Ilse, Grégoire, Marilaure, Kerckhof, Francis, Lacroix, Geneviève, Lindeboom, Han, Moens, Tom, Soetaert, Karline, Vanaverbeke, Jan, Van Hoey, Gert
• Format: Conference Object
• Language: unknown
• Published: 2016
• Subjects: North Atlantic
• Online Access: https://epic.awi.de/id/eprint/40807/; https://hdl.handle.net/10013/epic.47790

Marine renewable energy (MRE) projects are increasingly occupying the European North-Atlantic coasts and this is clearly observed in the North Sea. Given the expected impacts on the marine environment, each individual project is accompanied by a legally mandatory, environmental monitoring programme. These programmes are focused on the resultant effects on ecosystem component structure (e.g. species composition, numbers and densities) of single industrial projects. To date, there is a tendency to further narrow down to only a selection of ecosystem components (e.g. marine mammals and birds). While a wide knowledge-based understanding of structural impacts on (a selection of) ecosystem components exists, this evidence is largely lacking when undertaking impact assessments at the ecosystem functioning level (e.g. trophic interactions, dispersal and nutrient cycling). This critical knowledge gap compromises a scientifically-underpinned answer to the “so what” question of environmental impacts, i.e. whether the observed impacts are considered to be good or bad, or acceptable or unacceptable. The importance of ecosystem functioning is further acknowledged in the descriptors 4 and 6 of the Marine Strategy Framework Directive (EU MSFD) and is at the heart of a sustainable use and management of our marine resources. There hence is a fundamental need to focus on ecosystem functioning at the spatial scales at which marine ecosystems function when assessing MRE impacts. Here, we make a plea for an increased investment in a large (spatial) scale impact assessment of MRE projects focused on ecosystem functioning. This presentation will cover a selection of examples from North Sea MRE monitoring programmes, where the current knowledge has limited conclusions on the “so what” question. We will demonstrate how an ecosystem functioning-focused approach at an appropriate spatial scale could advance our current understanding, whilst assessing these issues. These examples will cover biogeochemical cycling, food webs and connectivity ...