Elevation and plant species identity jointly shape a diverse arbuscular mycorrhizal fungal community in the High Arctic

Knowledge about the distribution and local diversity patterns of arbuscular mycorrhizal (AM) fungi are limited for extreme environments such as the Arctic, where most studies have focused on spore morphology or root colonization. We here studied the joint effects of plant species identity and elevation on AM fungal distribution and diversity. We sampled roots of nineteen plant species in eighteen locations in Northeast Greenland, using next generation sequencing to identify AM fungi. We studied the joint effect of plant species, elevation, and selected abiotic conditions on AM fungal presence, richness, and composition. We identified twenty-nine AM fungal virtual taxa (VT), whereof six represent putatively new VT. AM fungal presence increased with elevation, and as vegetation cover and the active soil layer decreased. AM fungal composition was jointly shaped by elevation and plant species identity. We demonstrate that the Arctic harbours a relatively species-rich and non-randomly distributed diversity of AM fungi. Given the high diversity and general lack of knowledge here exposed, we encourage further research into the diversity, drivers and functional role of AM fungi in the Arctic. Such insight is urgently needed for an area with some of the globally highest rates of climate change.