Acknowledgements
Fieldwork for this study, including travel to and stay at Arctic Station was funded through the transnational access program INTERACT – International Network for Terrestrial Research and Monitoring in the Arctic. I am grateful to the Government of Greenland for sampling permission. I express my thanks to Anders Michelsen and Daan Blok for support with fieldwork preparation and sample transport. I thank Lennard van Rij for field assistance and Till Groh for lab assistance.