[Socio-ecological restoration, a concrete transposition of the normative concept of nature-based solutions?]

“Nature-based solutions” (NBS) are now widely referred to as a way of making anthropized ecosystems more sustainable. NBS stems from the principles of ecological engineering as conceptualized by H. T. Odum. Odum (1962), based on an approach centered on energy flows and ecosystem self-regulation. Despite their growing popularity, the implementation of these NBS remains complex and often focused solely on societal benefits, with little benefit to biodiversity. The current climate and ecological crisis calls for a reconsideration of our relationship with nature, integrating both social and ecological objectives in a new mobilization of societies and ecosystems in crisis. This is what is advocated by socio-ecological restoration, a recent concept developed during the reconstruction of coastal cities after the 2011 tsunami in Japan. This concept proposes the joint repair of ecosystems and human social cohesion, using elements of the ecosystem taken as historical landmarks before disturbance, enabling a local anchoring to regain a viable social and ecological trajectory. Socio-ecological restoration is not a classic program activity, but a social process in which several actors get involved by relying on each other, without using the expression itself. We propose to generalize this socio-ecological restoration, beyond post-disaster or post-conflict situations, to modify development practices and create real synergies between living humans and non-humans. In this respect, we use the reopening of the Bièvre River in the Paris region as an example of relevant socio-ecological restoration, because it involves the local community and responds to ecological issues. In conclusion, we make five recommendations for adapting the principles of socio-ecological restoration to the implementation of NBS, with a view to making not only our environments more resilient in the face of global change, but also those environments that concern the entire non-human living world and are often overlooked in field practices. By opting for a more eco-centric approach, NBSs could be in line with the IUCN’s initial definition, ultimately becoming Solutions Based For and By Nature, in line with the challenges of an effective ecological transition in the field.