Diversity and community assembly of moss-associated fungi in ice-free coastal outcrops of continental Antarctica

To date, the relative roles of niche-related (e.g., environmental filtering and biological interactions) and non-niche-related (e.g., dispersal limitation) processes in the assembly of fungal communities have rarely been explored in ice-free coastal outcrops of continental Antarctica. Here, using variation partitioning, we show that the community composition of fungi associated with moss colonies sparsely distributed in ice-free coastal outcrops of East Antarctica is affected by a suite of environmental conditions more significantly than by geographic distance, indicating the primary importance of niche-related factors. This was mainly attributable to the widespread occurrence of the predominant, cosmopolitan fungal species, Phoma herbarum. The variance explained by spatial factors increased when the analysis was applied only to the dataset of the Lützow-Holm Bay area (by excluding the data of the Amundsen Bay area, which is 500 km from the Lützow-Holm Bay area), indicating the local importance of non-niche-related processes.