Wide divergence of fungal communities inhabiting rocks and soils in a hyper‐arid Antarctic desert

• Published in: Environmental microbiology Vol. 25; no. 12; pp. 3671 - 3682
• Main Authors: Canini, Fabiana, Borruso, Luigimaria, Newsham, Kevin K., D'Alò, Federica, D'Acqui, Luigi P., Zucconi, Laura
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.12.2023; Wiley Subscription Services, Inc
• Subjects: Abundance; Antarctic Regions; Bacteria; Deserts; Divergence; Fungi; Fungi - genetics; Microbial activity; Microbiomes; Microbiota; Microorganisms; Mycobiome; Photosynthesis; Porosity; Rock; Rocks; Soil; Soil - chemistry; Soil Microbiology; Soil porosity; Soils; Species classification; Species richness; Substrates; Yeast; Yeasts; Antarctic Regions
• ISSN: 1462-2912; 1462-2920
• DOI: 10.1111/1462-2920.16534

Highly simplified microbial communities colonise rocks and soils of continental Antarctica ice‐free deserts. These two habitats impose different selection pressures on organisms, yet the possible filtering effects on the diversity and composition of microbial communities have not hitherto been fully characterised. We hence compared fungal communities in rocks and soils in three localities of inner Victoria Land. We found low fungal diversity in both substrates, with a mean species richness of 28 across all samples, and significantly lower diversity in rocks than in soils. Rock and soil communities were strongly differentiated, with a multinomial species classification method identifying just three out of 328 taxa as generalists with no affinity for either substrate. Rocks were characterised by a higher abundance of lichen‐forming fungi (typically Buellia, Carbonea, Pleopsidium, Lecanora, and Lecidea), possibly owing to the more protected environment and the porosity of rocks permitting photosynthetic activity. In contrast, soils were dominated by obligate yeasts (typically Naganishia and Meyerozyma), the abundances of which were correlated with edaphic factors, and the black yeast Cryomyces. Our study suggests that strong differences in selection pressures may account for the wide divergences of fungal communities in rocks and soils of inner Victoria Land. We tested the differential selective pressure of rock and soil habitats on fungal communities in Antarctic deserts. We found a strong differentiation of the communities in the two habitats characterised by different microclimatic conditions. Rocks were dominated by lichenized fungi, while soils by yeasts.