1. LEQUiA, Institute of the Environment, Universitat de Girona, Carrer Maria Aurèlia Capmany 69, Girona 17003, Spain
2. Department of Civil Engineering and Architecture, University of Pavia, Via Ferrata 1, 27100 Pavia, Italy
3. Group of Molecular Microbial Ecology. Institute of Aquatic Ecology, Universitat de Girona, Carrer Maria Aurèlia Capmany 40, Girona 17003, Spain