Microbial diversity and associated metabolic potential in the supraglacial habitat of a fast-retreating glacier: a case study of Patsio glacier, North-western Himalaya.

In the present study, we investigated the microbial community composition and their associated metabolic potentials using the 16S rRNA gene (V3-V4) and ITS (ITS1) amplicon sequencing approach in the Patsio glacier. The bacterial community composition was mainly dominated by Bacteroidota (18%-38% of total reads) and Cyanobacteria (9%-30%), along with a rare Candidate phylum Patescibacteria. Ferruginibacter (13%) and Polaromonas (8%) were the most dominant genera identified across the samples known to have potential ecological roles in colonization, driving the functioning of supraglacial habitats. The prevalence of metabolic genes associated with nitrogen, carbon and sulfur cycling processes was identified in the present study. The fungal diversity was dominated by members of unclassified phyla, followed by Ascomycota (up to 6%) and Basidiomycota (up to 4%), in terms of its relative abundance. The relative abundance of Fusarium and Didymella (8%-14%) was higher among the high altitude, cryoconite samples (P1-P5), while Rhodotorula (12%-29%) dominated in the glacial ice debris samples (P6-P8). Thus, our study provides significant insights into dynamics of microbial communities and its potential ecological roles in the changing climate.