The LTSER Zone Atelier Loire belongs to LTER-France network. The ZAL studies the Loire River basin (127 000 km2) on a long term scale (-15000 years until today). It focuses on the functionning of the hydrosystem, the human societies living there and on the co-evolution hydrosystem – society. The LTSER hosts several study sites subjected to measurement or data collection campaigns during work involving different disciplines as well as managers around a key question. The Maine watershed site is a large area to study dynamics of a low-energy river draining a 22,000 km² basin. The Louroux (Indre-et-Loire) site includes operation of an agricultural catchment area (24 km²). The bog of la Guette (Cher, Sologne, 25 ha) is an instrumented site to follow the rehabilitation of eco-hydrological services (storage of carbon, hydrology, biodiversity). Mareau-aux-prés islands (Loiret, St-Mesmin, 13 ha) is a site subjected to river dynamics which allows to understand the impacts of works carried out in the dyked bed and dynamics of the landscapes.