Mycobiota of Underground Habitats: Case Study of Harmanecká Cave in Slovakia

Abstract

Harmanecká Cave is located in the Harmanec Valley to the northwest of Banská Bystrica city, in the southern part of the Great Fatra Mountains, Slovakia. This cave is the most important underground locality of bat occurrence in Slovakia (population of 1000 to 1500 individuals). The study aimed at mycological evaluation of the air, the water, and the rock surface of Harmanecká Cave in Slovakia. The samples were taken on 24 July 2014. To examine the air, the Air Ideal 3P sampler was used. Microbiological evaluation of the rock surface was performed using swab sampling and the water by using the serial dilution technique. The authors observed a relationship between air temperature and the concentration of fungi. The concentration of airborne fungi increased with the increase in the air temperature and decreased with distance from the entrance to the cave. The density of airborne fungi isolated from the outdoor air samples was 810.5 colony-forming units (CFU) per 1 m3 of air and from 27.4 to 128.5 CFU for the indoor air samples. From the rock surface inside the cave, 45.0 to 106.6 CFU per 1 cm2 were isolated, whereas from the water, 29.9 CFU per 1 ml were isolated. Seven species of filamentous fungi were isolated from the external air samples and 12 species of filamentous fungi and 3 species of yeast-like fungi from the internal air samples. From the surface of the rocks inside the cave, 5 species of filamentous fungi and 1 species of yeast-like fungi were cultured, whereas from the water samples, 6 species of filamentous fungi were cultured. Cladosporium spp. were the fungi most frequently isolated from the external air; from the internal air, Penicillium urticae was most frequently isolated; from the rock surface, it was Gliocladium roseum; and from the water, it was P. chrysogenum. The species found in the cave can be pathogenic for humans and animals, especially for immunocompromised persons, and they can also cause biodegradation of the rocks. However, the concentration of airborne fungi inside the cave did not exceed official limits and norms stated as dangerous for the health of tourists.

Substrate and spatial variables are major determinants of fungal community in karst caves in Southwest China

“…Most of the abundant genera observed in our study were also common in other caves, such as Acremonium , Alternaria , Aspergillus , Cephalotrichum , Cladosporium , Fusarium , Penicillium and Trichoderma (Popović et al, ; Vanderwolf et al, ; Zhang et al, ). Talaromyces , which was dominant in rock samples in this study, was also observed by Ogórek, Dylag, Visnovska, Tancinova, and Zalewski () and Ogórek, Višňovská, and Tančinová (). However, we also found uncommon fungi in this study.…”

“…Talaromyces, which was dominant in rock samples in this study, was also observed by Ogórek, Dylag, Visnovska, Tancinova, and Zalewski (2016) and Ogórek, Višňovská, and Tančinová (2016). However, we also found uncommon fungi in this study.…”

“…Because of the lack of studies, fungal dispersal in caves remains poorly understood. Ogórek, Dylag, et al () and Ogórek, Višňovská, et al () investigated airborne fungi and RIF in caves in Slovakia and found that they decreased from the entrance to the bottom of the cave. In contrast, in the study performed by Man (), an increasing trend for airborne fungi was found in Heshang Cave.…”

Dark stains on rock surfaces in Driny Cave (Little Carpathian Mountains, Slovakia)

“…(Nováková 2009; Bezerra et al 2012; Ogórek et al 2016a, b). The literature also reported that the active growth of this species was found on marten excrement in Domica Cave (Slovakia), but it was identified only by morphological features and without detailed characterization (Nováková 2005).…”

“…Additionally, microscopic fungi and bacteria may be isolated from various substrates and places in caves and other underground sites such as air, sediments, vermiculations, bat guano, decaying organic material, rock surfaces, bioaerosols, etc. (Nováková 2009; Ogórek et al 2016a, b; Walochnik and Mulec 2009; Vanderwolf et al 2013; Borda et al 2014; Popović et al 2015). …”