1. Université de Lyon, Lyon, F–69003; Université Lyon 1, Villeurbanne, F–69622; ENTPE, Vaulx‐en‐Velin, F–69518; CNRS UMR 5023 ‘Ecologie des Hydrosystèmes Naturels et Anthropisés’, F–69622 Villeurbanne, France
2. Netherlands Institute of Ecology (NIOO‐KNAW) – Centre for Estuarine and Marine Ecology, PO Box 140, NL–4400 AC Yerseke, the Netherlands
3. Institut Universitaire de France, Paris, F–75005, France
4. Institute of Water and Wetland Research – Radboud University Nijmegen, Toernooiveld, NL–6525 ED Nijmegen, the Netherlands
5. Section of Plant Ecology & Biodiversity – Institute of Environmental Biology, Utrecht University, PO Box 800.84, NL–3508 TB Utrecht, the Netherlands