1 Irstea, UR OPAALE, 17 av. de Cucillé, CS 64427, F-35044, Rennes, France; Université Rennes 1, 2 rue du Thabor, CS 46510, 35065, Rennes Cedex, France; Université Bretagne Loire, France.
2 Irstea, UR OPAALE, 17 av. de Cucillé, CS 64427, F-35044, Rennes, France; Université Bretagne Loire, France. Electronic address: romain.girault@irstea.fr.
3 Irstea, UR OPAALE, 17 av. de Cucillé, CS 64427, F-35044, Rennes, France.
4 Irstea, UR OPAALE, 17 av. de Cucillé, CS 64427, F-35044, Rennes, France; Université Bretagne Loire, France.