1. Department
of Geology, Lund University, Sölvegatan 12, SE-22362 Lund, Sweden
2. Department
of Biology, University of Copenhagen, Universitetsparken 4, DK-2100 Copenhagen, Denmark
3. Department
of Applied Environmental Science, Stockholm University, Svante Arrhenius
väg 8, SE-11418 Stockholm, Sweden
4. Department
of Earth Sciences, Utrecht University, Post Office Box 80.021, 3508 TA Utrecht, Netherlands