1. Terrestrial Ecology Section; Department of Biology; University of Copenhagen; Universitetsparken 15 Copenhagen Ø DK-2100 Denmark
2. Environmental Microbiology and Biotechnology; Department of Environmental Science; Aarhus University; Frederiksborgvej 399 DK-4000 Roskilde Denmark
3. Institute of Urban Environment; Chinese Academy of Sciences; 1799 Jimei Road Xiamen 361021 China
4. Arctic Station; University of Copenhagen; P.O. Box 504 3953 Qeqertarsuaq Greenland