1. Croatian Forest Research Institute, 10450 Jastrebarsko, Croatia
2. Department of Geobotany, Faculty of Regional and Environmental Sciences, University of Trier, 54296 Trier, Germany
3. Earth and Life Institute, Université Catholique de Louvain, B-1348 Louvain-la-Neuve, Belgium
4. Faculty of Forestry and Wood Technology, University of Zagreb, 10000 Zagreb, Croatia
5. Swiss Federal Institute for Forest, Snow and Landscape Research WSL, CH-8903 Birmensdorf, Switzerland
6. Institute of Terrestrial Ecosystems, ETH Zurich, CH-8092 Zurich, Switzerland