Environmental samples have been taken during summer in the Arctic Ocean and the Southern Ocean, respectively. During the project, different water depths, covering the surface water, the chlorophyll max (where the major phytoplankton groups reside) and the under-ice water were sampled and DNA was extracted for characterization. Two phylogenetic informative markers were sequenced in order to study the marine fungal community (ITS2 region) as well as the wider microbial eukaryotic community (V4 region). This approach allowed for the identification of putative distribution patterns. Furthermore, relationships between marine-derived fungal community structures and environmental parameters were elucidated using statistical tests.
Preliminary results of this project revealed a high diversity of unclassified marine fungi, particular in high Arctic regions. Comparisons with chytrid sequence data from public databases originating from different oceanographic regions showed a close phylogenetic relationship between chytrids from cold-water environments compared to those originating from temperate oceanographic regions. This finding suggests a potential biogeographic distribution of chytrids. To evaluate potential environmental factors, influencing fungal community structure and distribution, different parameters have been tested. The data revealed an effect for sea ice concentration and salinity. In terms of chytrids, this groups was mainly recovered in ‘low saline’, sea ice melt influenced sampling sites. Microbe-microbe co-association analyses, indicated a correlation between certain diatom species and chytrid prevalence. The results of this study are submitted for publication in a peer review journal.
