1. Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, Amsterdam, Netherlands
2. Department of Aquatic Ecology & Environmental Biology, Institute for Water and Wetland Research, Radboud University, Nijmegen, Netherlands
3. Altenburg and Wymenga Ecological Consultants, Veenwouden, Netherlands
4. Witteveen+Bos, Deventer, Netherlands
5. Department of Botany, Swedish Museum of Natural History, Stockholm, Sweden