The 2013 annual meeting of the working group ‘Marine Benthal and Renewable En-ergy developments’ was held on the 19-22 March at the laboratory of 'Continental and Coastal Morphodynamic' in Caen, France. The meeting was attended by 21 ex-perts, representing nine countries (Belgium, Estonia, France, Germany, Ireland, Po-land, Sweden, UK, Netherlands). The meeting was co-chaired by Jennifer Dannheim (Alfred Wegener Institute, Germany) and Andrew B. Gill (Cranfield University, UK). The terms of references were summarized in three thematic subgroups: (A) The ‘knowledge group’ (ToR A, E) will evaluate and review existing knowledge of the effects of offshore renewable constructions and related topics (e.g. artificial reefs). (B) The ‘monitoring group’ (ToR B, F) will review and evaluate sampling techniques the scientific efficiency of ongoing monitoring programmes of offshore renewable con-struction projects by identifying knowledge gaps and simplifying future standard-ized research. (C) The ‘metadatabase group’ (ToR C, D) will develop a database of metadata that will help to cross-foster research and target monitoring, as well as fu-ture modelling approaches.
The knowledge group will develop a set of hypothesis-driven pathways from a con-ceptual scheme of cause–effect relationships (outcome of the WKEOMB) and will evaluate how knowledge of related topics (e.g. artificial reefs) can contribute to the issue of effects of renewable energy constructions. The disentanglement of the con-ceptual scheme began with consideration of components of relevance to societal is-sues, i.e. the benthal being (1) a ‘biogeochemical reactor’, (2) a source of biodiversity and (3) a source of food resources for higher trophic levels. Schemes were simplified and text descriptors of the processes (i.e. the hypotheses) that link the remaining components were formulated. During subsequent meetings, prioritization of the most important cause–effect relationships and the description of the main pathways of cause–effect-chains will be done.
The monitoring group will review why monitoring is needed, what needs to be moni-tored and how best to achieve those needs. This requires reviewing existing guidance for monitoring for marine renewables and other relevant marine activities. It was identified that time and spatial scale was crucial to the determination of the need to monitor and consequently what data should be collected and the best methodologies. Also identification of the type and extent of change, in the context of determining any significance, compared to natural variability and other effectors of change to the ben-thal community. The next stage is to write a review paper concerning monitoring and the crucial issues that were identified by the group. This will then be linked into the activities of the other two groups.
The metadatabase group was suggested to link to the Téthys ANNEX IV knowledge-management system, which is a USA-led collaborative project to gather and share information on the environmental effects of ocean energy development (tidal, wave, and ocean current) under the auspices of the Ocean Energy Systems (OES). A metadatabase will improve information exchange and guidelines for sampling tech-niques on renewable energy construction monitoring techniques (linked back to the monitoring group) and will simplify collaboration in the research field of marine re-newables effects on the benthal in the future.