Archaeal and bacterial profiles of intact microbial communities from MASE environments. Panel a shows the taxonomic profile obtained using the Archaea-targeting primer, on phylum (upper bar chart) and family level (below). Phyla names are followed by relative abundances (all datasets); no archaeal signatures were obtained from the glacier samples. Panel b shows the bacterial composition of all samples on class level (only those classes with > 0.1% are shown). Panel c displays the most abundant phyla of the microbial community (based on “universal” primer set, “microbiome”). For all panels, the relative abundance of each taxon is shown on the y-axis. The total relative abundance, summed up for all samples, is given in brackets behind the taxa names in the legends. For unclassified RSVs (“unassigned”) the highest assigned taxonomic level is given. For instance, “Archaea, not assigned” reflects all RSVs which were classified on Archaea level, but could not be assigned to other taxonomic levels. Full detail on the archaeal and universal dataset is given in Additional file 2: Supplementary Tables 2 and 3.