Rewilding Coastal Areas
The Planetology and Geosciences Laboratory (LPG) and the Centre Jean-Bodin are part of the European Rewrite project (Restoration of InterTidal sediment Ecosystems for carbon sequestration, climate adaptation and biodiversity support). The project's goal is to provide public authorities with scenarios for the "rewilding" of intertidal zones, which are covered at high tide and uncovered at low tide. These could prove invaluable in the face of climate change.
Analyses will help us to understand how these systems work.
Mudflats, seagrass beds, salt marshes... intertidal zones are home to an incredible wealth of biodiversity and serve as nurseries for many species. As buffer zones, they are able to absorb the force of the tides or the flooding of rivers. "They are also potential carbon sinks," adds Édouard Metzger, professor of geology at the Planetology and Geosciences Laboratory (LPG). "Overall, these are sites that could help mitigate the effects of climate change. That's one of the things we'll be looking at in the Rewrite project: trying to understand as best we can how this works".
Coordinated by the University of Nantes, led by Professor Vona Méléder-Tard, Rewrite brings together 25 public and private partners, including 17 universities and laboratories. In particular, they will study ten sites along the Atlantic coast in Europe, from Portugal to Ireland, as well as in Canada and the United States. In France, the work will focus on the Loire estuary and Bourgneuf Bay.
Coveted areas
Everywhere, intertidal zones have attracted human activity. "They are at the heart of many issues, including hunting, fishing, agriculture and the development of port areas," confirms Édouard Metzger. That's why, in addition to environmental specialists, the project is bringing on board academics in human and social sciences, sociologists, historians, and a legal expert, Arnaud de Lajartre, lecturer in heritage and environmental law at the University of Angers and member of the Centre de recherche juridique et politique Jean-Bodin. He explains: "We will analyse how we got to where we are today in terms of the management of these coastal areas,".
Arnaud de Lajartre is assisted in his mission by Solena Puig, a young lawyer hired for the project for a few months. Together, they will carry out a diagnostic of the international and European texts and national and local regulations that apply to the ten selected demonstrators. "From one country to another, we obviously don't all have the same regulations. However, intertidal zones are land that belongs to someone, be it the State, a local authority, private individuals, etc. If we're going to consider rewilding, we'll need to take this parameter into account".
A 5-year project
Beyond simply making an observation, the project should result in a tool to facilitate public decision-making. By understanding the biogeochemical, ecological and social functioning of these areas, the Rewrite partners will work together to define different scenarios (do nothing, restore, return to nature) "that will enable the managers of these sites to choose a trajectory for these places, so as to create either a system that will absorb the maximum amount of CO2, or increase biodiversity, or that will offer the best protection for coastal areas", explains Édouard Metzger, who is working with half a dozen members of the LPG on this project. "And for all these scenarios, we will have defined what legal levers can be mobilised to achieve this and what obstacles may exist," adds Arnaud de Lajartre.
Rewrite will deliver its conclusions at the end of 2028. The programme is being funded by the European Commission with €9 million, of which €140,000 is for the work of researchers from Angers.
