Ecosystem services generated by rivers in very good ecological status (example of the Léguer (22) and the Estéron (06), rivers labeled "wild river sites")[Les services écosystémiques générés par les rivières en très bon état écologique (exemple du Léguer (22) et de l'Estéron (06), rivières labellisées "Sites rivières sauvages")]

The preservation of ecosystems/hydrosystems in very good ecologically healthy water or poorly impacted by human activities represents a capital challenge for the safeguarding of biodiversity/resources... Thus, the study being finalised in partnership with the OFB, Cerema, ERN, CentraleSupélec and the "association rivières sauvages" aims to address the dynamics of the interdependent relationships between an ecosystem of excellence and the actors who benefit from it, in order to shed light on the modalities of an adapted sustainable management taking into account the concept of ecosystem services provided by rivers labelled "wild river sites". To do this, 2 watersheds (Léguer (22) and Estéron (06)) have been analysed thanks to the assistance of the "Bassin versant du Léguer" and the development council of the Regional Natural Park of "Préalpes d'Azur", essential relays between the actors of territories and the research team. Several stages were carried out during the study, in particular (i) the collection of initial data for the socio-ecological study of the Estéron and Léguer catchment areas and their territory of influence; (ii) the identification of interdependencies, synergies, conflicts, between ecosystem services which allow to highlight the notion of a bundle of services and (iii) the biophysical and economic assessment of 4 services selected by the local steering committees. Finally, in order to qualify the attachment of the inhabitants to the Léguer Valley, development scenarios used for the construction of questionnaires have been elaborated in order to evaluate the willingness to pay of the local actors for their territory, but also to highlight the upstream-downstream solidarities of the territories via the example of the Estéron watershed which supplies drinking water to part of the Nice agglomeration. According to the watersheds studied, the 4 ecosystem services selected by the local stakeholders differ slightly but the availability of drinking water with little or no treatment, wood energy and CO2 carbon sequestration provided by the forest and the " bocage Breton" (particularity of the Leguer), outdoor activities (including hunting, fishing, hiking, kayaking ...) and the notion of attachment of the inhabitants to their valley (Leguer) or the feeling of tranquillity of the place (Estéron) are strong concepts that have been identified by the local steering committees.