Phenotypic and genotypic diversity of airborne fungal spores in Demänovská Ice Cave (Low Tatras, Slovakia)

This paper is the first aero-mycological report from Demänovská Ice Cave. Fungal spores were sampled from the internal and external air of the cave in June, 2014, using the impact method with a microbiological air sampler. Airborne fungi cultured on PDA medium were identified using a combination of classical phenotypic and molecular methods. Altogether, the presence of 18 different fungal spores, belonging to 3 phyla, 9 orders and 14 genera, was detected in the air of the cave. All of them were isolated from the indoor samples, and only 9 were obtained from the outdoor samples. Overall, airborne fungal spores belonging to the genus Cladosporium dominated in this study. However, the spores of Trametes hirsuta were most commonly found in the indoor air samples of the cave and the spores of C. herbarum in the outdoor air samples. On the other hand, the spores of Alternaria abundans, Arthrinium kogelbergense, Cryptococcus curvatus, Discosia sp., Fomes fomentarius, Microdochium seminicola and T. hirsuta were discovered for the first time in the air of natural and artificial underground sites. The external air of the cave contains more culturable airborne fungal spores (755 colony-forming units (CFU) per 1 m3 of air) than the internal air (from 47 to 273 CFU in 1 m3), and these levels of airborne spore concentration do not pose a threat to the health of tourists. Probably, the specific microclimate in the cave, including the constant presence of ice caps and low temperature, as well as the location and surrounding environment, contributes to the unique species composition of aeromycota and their spores in the cave. Thus, aero-mycological monitoring of underground sites seems to be very important for their ecosystems, and it may help reduce the risk of fungal infections in humans and other mammals that may arise in particular due to climate change.