1. Institute of Landscape Ecology and Resources Management, Research Centre for BioSystems, Land Use and Nutrition; Justus-Liebig-Universität Giessen; Giessen Germany
2. Now at Department of Hydrology, Water Resources Management and Environmental Engineering; Ruhr-Universität Bochum; Bochum Germany
3. Now at alpS GmbH; Innsbruck Austria
4. Now at Department of Biological and Ecological Engineering; Oregon State University; Corvallis Oregon USA