Denis Lacroix

The Mediterranean is one of the world’s most remarkable regional seas, with a high level of activity in several sectors: fishing, mining, industry, town expansion, trade and tourism. However, the opportunities are currently outweighed by the threats, particularly in terms of marine and coastal resources. Nevertheless, the increasing knowledge and awareness amid the region’s societies and States of the risk of negative impacts related to unpredictable changes lie behind an ever greater determination to understand the various phenomena involved and to make choices conducive to more positive change. Moreover, Mediterranean ecosystems seem to provide increasing opportunities for various forms of “Blue Growth” – as long as resources are considered as a legacy rather than a mine to be endlessly exploited: the management of resource flows should gradually take precedence over the exploitation of stocks. But for this to become a reality, comprehensive and relevant data sets, methods and objectives are needed in all disciplines, from physics to governance. Meanwhile, the social aspects of the issue are emerging in a variety of ways, via new demands from a public that is increasingly aware of food security, health, sustainability and ethics. There is therefore an urgent need for greater cooperation among all actors, coupled with an ability to outline the long-term choices in a context of uncertainty and increasing risk. In marine sciences–including social studies, research must draw on shared and open methods to (i) help facilitate the debates between all stakeholders; (ii) contribute to the collective selection of measures that will not later be regretted and (iii) promote a sense of ownership among all parties of the actions necessary in the Mediterranean. As with the climate change issues, research in the Mediterranean must contribute to avoiding the unbearable while managing the inevitable, at least as far as possible within this iconic maritime region.

The pressures on the use of the seashore are steadily rising, not only in developed countries but worldwide. Anthropogenic activity has long impacted the marine continental shelf down to a depth of approximately –200 m. New activities are now affecting this coastal space such as renewable energies, recreational uses and aquaculture in addition to the traditional ones of navigation or fishing. This evolution raises new sources of conflict amongst users which can require state involvement in order to manage the different stakeholders and pressure groups. However, the coastal space still offers a large potential for development for two reasons. Firstly, the physical three dimensional potential of this space enables the whole water column to be used, principally to increase the fishing productivity as in Japan. Secondly, innovative synergies can be created between socio-technical and ecological uses (a “fourth dimension”) such as the eco-design of wind turbine foundations in order to create fish habitat or sea grass settlement. This new vision in “4D” for the design and the management of coastal infrastructure can potentially reduce the risk of conflict as different uses of the coastal space would not necessarily exclude one another. Indeed, several forms of synergy could be developed such as fisheries with aquaculture or biological sustainability with social acceptability. Until now, limited attempts at such an approach have been done. We suggest this is likely due to the absence of a common eco-engineering vision and the lack of experience amongst biologists and engineers in the co-construction of projects. This eco-engineering, or “green” vision, also takes into account the complexity and resilience of the ecosystem in the long term, if underwater engineered infrastructures are also “eco”-designed to increase ecological gain This new conception, for development within the coastal area, provides for an increased bio-oriented complexity to engineered structure and therefore a better resistance of the ecosystem in the long term to anthropogenic pressures and a reduction in multi-user conflicts.