1. Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research Research Unit Potsdam Telegrafenberg A45 Potsdam 14473, Germany
2. Vinogradov Institute of Geochemistry Siberian Branch of Russian Academy of Science Favorsky str. 1a Irkutsk 664033, Russia
3. Department of Ecology and Genetics University of Oulu Oulu 90014, Finland
4. Institute of Limnology Russian Academy of Sciences Sevastyanova str. 9 St. Petersburg 196105, Russia
5. Institute of Geology and Mineralogy University of Cologne Zuelpicher Str. 49a Cologne 50674, Germany
6. Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research Am Alten Hafen 26 Bremerhaven 27568, Germany
7. Arctic and Antarctic Research Institute Bering str. 38 St. Petersburg 199397, Russia
8. Institute of Earth Sciences St. Petersburg State University Universitetskaya nab., 7–9, St. Petersburg 199034 Russia