1. Department of Geobiology, University of Göttingen, Göttingen, Germany
2. Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland
3. Landcare Research, Dunedin, New Zealand
4. School of Biological Sciences, University of Auckland, Auckland, New Zealand
5. Department of Soil Science of Temperate Ecosystems, Büsgen-Institute, University of Göttingen, Göttingen, Germany
6. Finnish Museum of Natural History, University of Helsinki, Finland
7. Department of Biosciences, University of Helsinki, Finland