DNA Metabarcoding Focusing on Eukaryote Communities on Langhovde Glacier, East Antarctica

Ecological structures and habitats of eukaryote communities in supraglacial environments have attracted attention because of their unique biodiversity and potential impact on glacial surface melt. In this study, we investigated the microbial community on Langhovde Glacier in East Antarctica, wherein few molecular biological studies have been conducted. We performed a comprehensive environmental DNA analysis and dissolved ion measurements focusing on various types of supraglacial waters scattered on Langhovde Glacier, as well as ponds in the adjacent off-ice area. 18S rRNA gene analysis revealed the presence of diverse eukaryotic taxa on the glacier, including Chlorophyta, Chrysophyceae, Cercozoa, Choanoflagellatea and Streptophyta. Distinct ecological structures were observed between large perennial supraglacial lakes and small transient supraglacial puddles on the glacier. Moreover, microbial diversity was greater in the off-ice ponds with elevated concentrations of dissolved ions. Only a limited number of eukaryotic gene sequences were shared on- and off-ice sites, and many of the gene sequences detected on Langhovde Glacier matched those from remote snow and ice fields worldwide. These results highlight the cosmopolitan nature of ice/snow algae and suggest that the physicochemical properties of the supraglacial water environment play a crucial role in shaping microbial diversity on glacier surfaces.