The general objectives are to position ourselves as a reference research center in the Mediterranean area regarding the effects of global change (recent and future) in the functioning of river ecosystems, and to develop transversal research at network level river in which all aquatic environments are considered, as well as their interaction with the terrestrial environment. Specifically, there are 3 lines of research within AI3: i) study of the effect of flow and temperature alterations on Carbon flows in fluvial systems; ii) study of the effects of low flows (hydrological drought) on the functioning of fluvial biofilms and biogeochemical cycles; iii) study of ecosystem services.