1. Laboratory of Hydrology and Geochemistry of Strasbourg (LHyGeS); University of Strasbourg/ENGEES; CNRS, 1 rue Blessig F-67084 Strasbourg CEDEX France
2. Association pour la Relance Agronomique en Alsace (ARAA); 2 rue de Rome 67300 Schiltigheim France
3. Faculty of Geo-Information Science and Earth Observation ITC; University of Twente; Enschede The Netherlands