Background This paper aims to explore some aspects of the questioning developed as part of the 'Mental'eau' project, funded from 2023 to 2027 by the Rhine-Meuse Water Agency (Grand Est region, France). This research proposes an interdisciplinary approach based on environmental and human sciences, as well as scientific mediation (Fries-Paiola, C. 2024). It brings together a multidisciplinary research team, who works at answer two main questions: from the ‘one health’ concept (World Health Organization 2023), is there a correlation between the health level of aquatic ecosystems and human health, understood here through the dimension of the well-being of the people who visit these ecosystems? This research addresses some unexplored questions (Gascon et al. 2017). As a matter of fact, the analysis of the impact of the use of a natural site on human well-being is confined mainly to the study of the human-forest relationship, and when these sites are aquatic ones, they are almost exclusively urban (e.g. Cardinali et al. 2024). In these researches, the ecosystems state of health is not addressed as a factor that can have an impact on human well-being; even in the ‘one health’ approaches, questions are more about zoonoses but rarely about mental health regarded in connection with the state of health of the ecosystems. Therefore, 28 aquatic ecosystems belonging to the Moselle River watershed in France have been chosen as the analysis corpus. The methodology developed proposes a three-pronged approach to these sites: an ecological dimension, with a protocol, which aims at assessing their state of health (Paul, A. 2024); a psycho-social dimension, with a survey that aims at assessing the felt well-being of the people who are visiting the sites (Denechaud, C. 2024); and a territorial dimension to understand the sites in their socio-spatial dimension, based on observations and mapping works. an ecological dimension, with a protocol, which aims at assessing their state of health (Paul, A. 2024); a psycho-social dimension, with a survey that aims at assessing the felt well-being of the people who are visiting the sites (Denechaud, C. 2024); and a territorial dimension to understand the sites in their socio-spatial dimension, based on observations and mapping works. In conjunction with the exhaustive analyses of these 28 sites with this triple approach, the research will focus on a restricted corpus of 6 to 8 sites (chosen for their representative ecological and social components) in order to question, on one hand, the effects of sensitization on the representation of relationships to the aquatic ecosystems and, on the other hand, how understanding a site from a 'one health' perspective could impact its management, based on participatory workshops with stakeholders and local residents. Objectives The paper will question specifically theoretical and methodological issues, as well as first outcomes from the development of the social-spatial approach of both general and restricted corpus. Three aspects will be particularly developed. The first point will concern the contribution of an approach based on spatiality (site, territory and landscape) and on the diversity of points of view of different stakeholders (individuals in situ, users and inhabitants) and managers (elected officials, technicians or advocates), to understanding the relationships between these stakeholders and the sites. The second point will address the various aspects underlying the question of well-being by looking at how these sites are experienced and represented by the various stakeholders. What are the tensions between uses and practices, or between perceived ecosystem services and disservices? How does the sense of belonging to the aquatic ecosystem impact the relationships with the site? The third point will outline the way arbitrations can be thought of in terms of practices and management of these sites, in relation with the concept of ‘one health’. To say it differently, what is the level of perceived congruency between the interests of the ecosystem and those of the different stakeholders? Results In relation to objectives previously presented, this paper will try to identify first outcomes after two years of work. After a little more than one year to constitute the corpus, this spring will be dedicated to a big stage of field study. In addition to developing the theoretical and methodological aspects underlying the questions raised, this paper will analyze the initial results of various approaches: surveys and mapping works, participant and non-participant observations and first interviews (semi-directive and focus groups with different stakeholders). This paper will also propose a projection of the methodology, which will be developed as a part of workshops with the stakeholders from the sites of the restricted corpus. In the background to this paper, we will be looking at both the obstacles and levers to the effective implementation of interdisciplinary (between natural science disciplines and the humanities) and transdisciplinary (carried out in conjunction with local stakeholders) research (Chenorkian 2021).
Background In a global context undergoing profound transformation (climate change, collapse of biodiversity, new pandemics, social changes, etc.), the 'One Health' concept (World Health Organization 2023) may appear relevant both from a scientific point of view, to think about (and prevent) these crises, but also from a social - or even political - point of view, by proposing an additional way of making visible the ecosystemic interactions and interdependencies in which humans are involved. We explore this dual social and scientific aspect of the 'One Health' concept in Mental'Eau project, which focuses on the interface between humans and aquatic ecosystems (rivers, water bodies, canals). A preliminary literature review has shown that few studies have focused on the link between well-being and health in aquatic ecosystems. Co-funded by the Rhine-Meuse Water Agency, our 4-yr project proposes an interdisciplinary approach based on environmental sciences, human sciences and scientific mediation. It brings together a multidisciplinary research team (LIEC - Université de Lorraine CNRS, LHAC - Ecole Nationale Supérieure d'Architecture de Nancy, EABX and Beta - INRAE, ICube and LinCS - Université de Strasbourg CNRS) and the ‘Vigie de l'Eau’ association (Vittel), and involves local stakeholders. Objectives In this interdisciplinary research project, we are investigating the relationship that individuals have with aquatic ecosystems, as landscapes and environments for a variety of recreational practices. How can these ecosystems be a source of well-being for humans, and conversely, how can users' perceptions help to improve the quality of aquatic ecosystems? To what extent can we link human health and ecosystem health, from the perspective of the 'One Health' concept? Finally, how is this concept perceived and integrated (or not) by individuals, with possible implications for their practices and their experience of these environments? This research aims to link indicators of well-being (relaxation, ability to concentrate, happiness, serenity, creativity, etc.), as expressed by individuals frequenting places linked to water (rivers, lakes, etc.) with measurable indicators of the functionality and quality of these aquatic ecosystems (Observatoire National de la Biodiversité 2025) such as physico-chemical parameters, biodiversity. These scientific research objectives are complemented by more operational ones, which anchor the project presented in the field of action research. The project has three main operational targets: to raise awareness of the 'One Health' concept among the public visiting the various sites, through events, serious games, etc. to support local authorities in their decision-making on aquatic site development projects, through information meetings and the drafting of practical guidelines, and to provide scientific mediation for local residents in the vicinity of the sites studied, to present the research and its issues as well as its conclusions. to raise awareness of the 'One Health' concept among the public visiting the various sites, through events, serious games, etc. to support local authorities in their decision-making on aquatic site development projects, through information meetings and the drafting of practical guidelines, and to provide scientific mediation for local residents in the vicinity of the sites studied, to present the research and its issues as well as its conclusions. Outcomes First, a corpus of around 30 aquatic ecosystems was selected in the river Moselle watershed (Figs 1, 2, 3). These sites were selected based on both frequentation and functional characteristics criteria. The second step was to design a method for characterizing the ‘health’ of aquatic ecosystems. This work was carried out as part of an end-of-study internship at INRAE Bordeaux (Paul et al. 2025). The proposed method integrates indicators of ecosystem ecological integrity such as naturalness, diversity, water quality and ecological interest. Metrics are calculated on the basis of both physico-chemical and ecological parameters, and are represented by radar diagrams that provide a synthetic visualization of the ecosystem's state of health. Metrics are assessed at the 3 scales of the landscape, the immediate environment and the aquatic environment itself. This multimetric and multiscalar method is currently being finalized and should enable us to estimate the state of health of the ecosystem and its utilization for the sociological part of the study. Sociological surveys combining observation, questionnaires (around 50 per site) and interviews (around 10 per site) will be carried out in situ . To date, a questionnaire has been designed by Caroline Denechaud (PhD student) and will be tested on the sites from spring 2025. The questionnaire covers various items, namely the perception of the characteristics of the site visited (sensory experience), the appreciation of the experience (effect of the experience), and the perception of the ecological quality of the site (individual assessment of the state of the ecosystem) (Denechaud et al. 2025). Survey results will be used to derive indicators of human well-being. The last step will focus on analyzing the links between indicators of well-being and ecosystem health. Interpretation of these results will reveal, among other things, whether individuals relate their well-being to the health of the ecosystem and the indicators used, and whether there is resonance or dissonance between the state of well-being of individuals and the health of the ecosystems they visit. We are also looking into ways of raising awareness of the 'One Health' concept among the general public. These awareness-raising activities will be carried out at selected sites, using a serious game built by the association ‘La Vigie de l'Eau’ (Fig. 4). The results of the awareness-raising study will help to answer the following question: is a citizen who is aware of the 'One Health' concept more sensitive to the well-being provided by a good-quality environment and, conversely, does he think he can influence the health of the ecosystems he visits?
