Fungal and bacterial diversity of Svalbard subglacial ice

L Perini,C Gostinčar,N Gunde-Cimerman

doi:10.1038/s41598-019-56290-5

Abstract

The composition of fungal and bacterial communities in three polythermal glaciers and associated aquatic environments in Kongsfjorden, Svalbard was analysed using a combination of cultivation and amplicon sequencing. 109 fungal strains belonging to 30 mostly basidiomycetous species were isolated from glacial samples with counts up to 103 CFU/100 ml. Glaciozyma-related taxon and Phenoliferia psychrophenolica were the dominant species. Unexpectedly, amplicon sequencing uncovered sequences of Chytridiomycota in all samples and Rozellomycota in sea water, lake water, and tap water. Sequences of Malassezia restricta and of the extremely halotolerant Hortaea werneckii were also found in subglacial habitats for the first time. Overall, the fungal communities within a glacier and among glaciers were diverse and spatially heterogenous. Contrary to this, there was a large overlap between the bacterial communities of different glaciers, with Flavobacterium sp. being the most frequently isolated. In amplicon sequencing Actinobacteria and Proteobacteria sequences were the most abundant.

Highlights

The archipelago of Svalbard is located in the Arctic Ocean between Norway and the North Pole
We focused on fungal and bacterial communities found in the subglacial ice of these glaciers and in the associated aquatic environments such as clear ice floating in sea water, glacial meltwater, moraine lake water, sea water and lake-derived tap water
Fungal and bacterial diversity of subglacial ice of three polythermal glaciers and their surrounding aquatic environments were analysed by a combination of cultivation and molecular methods

Summary

Introduction

The archipelago of Svalbard is located in the Arctic Ocean between Norway and the North Pole It is one of the best studied locations in the Arctics and considered a “hot spot” of Arctic microbiological research. Studies of microbial glacial communities have focused on either Bacteria[1,2,3], Fungi[4,5,6,7], Archaea[8], or viruses[9,10]. Glaciers with a polythermal basal regime[11] are defined by the presence of water at the subglacial drainage system at their basis[12] They are entirely warm-based, except at the margins, meaning that liquid water present at the glacier bed is generated by surface flow, friction, pressure melting, and groundwater infiltration[13]. Our findings show a considerable diversity ( for fungi) amongst local microbial communities and include the presence of a number species not expected in the Arctic environment

Methods

Results

Discussion

Conclusion