Vol.:(0123456789) 1 3 Extremophiles DOI 10.1007/s00792-017-0967-6 ORIGINAL PAPER Efect of environmental parameters on biodiversity of the fungal component in lithic Antarctic communities Laura Selbmann 1  · Silvano Onofri 1  · Claudia Coleine 1  · Pietro Buzzini 2  · Fabiana Canini 1  · Laura Zucconi 1   Received: 28 July 2017 / Accepted: 21 September 2017 © Springer Japan KK 2017 Keywords Antarctic · Climate change · DGGE · Endolithic communities · Fungi Introduction Rock represents the earliest terrestrial niche for life at the time when microbes were the only life forms on Earth. At present, when conditions are too harsh for complex organ- isms, microbes remain the only settlers and even withdraw inside rocks if external environmental parameters become incompatible for active life. Airspace within rocks ofers microbiota a protected and bufered microenvironment and, actually, endolithic development allows life to expand into diferent extreme conditions, i.e., hot and cold deserts or geothermal environments (Friedmann and Ocampo 1976; Friedmann 1982; Bell 1993; Walker et al. 2005). Rocks are the prevailing substratum for life in Antarctica (Nienow and Friedmann 1993); soils generated in the distant past, when the continent was positioned at higher latitudes, were eroded by ice and winds once continental drift moved Antarctica into its present position at the South Pole (Selbmann et al. 2015). Highly oligotrophic soils of the McMurdo Dry Val- leys support relatively low biomass: an autotrophic com- ponent is lacking, prokaryotes are dominated as actinobac- teria, while eukaryotic assemblages are largely dominated by fungi, both flamentous and yeasts (Pointing et al. 2009; Rao et al. 2011; Lee et al. 2012). Rocky outcrops support the highest standing biomass in the Antarctic ice-free desert (Cowan and Tow 2004; Cary et al. 2010; Cowan et al. 2014). Some ice-free areas of continental Antarctica are consid- ered the best analogues for a Martian environment; there, the conditions approach the limits of tolerability for most life forms, and endolithic lifestyle is the most widespread type of colonization and often the sole possibility for survival Abstract A wide sampling of rocks, colonized by micro- bial epi–endolithic communities, was performed along an altitudinal gradient from sea level to 3600 m asl and sea distance from the coast to 100 km inland along the Victo- ria Land Coast, Antarctica. Seventy-two rock samples of diferent typology, representative of the entire survey, were selected and studied using denaturing gradient gel electro- phoresis to compare variation in fungal diversity according to environmental conditions along this altitudinal and sea distance transect. Lichenized fungi were largely predominant in all the samples studied and the biodiversity was heavily infuenced even by minimal local variations. The n-MDS analysis showed that altitude and sea distance afect fun- gal biodiversity, while sandstone allows the communities to maintain high biodiversity indices. The Pareto-Lorenz curves indicate that all the communities analyzed are highly adapted to extreme conditions but scarcely resilient, so any external perturbation may have irreversible efects on these fragile ecosystems. Communicated by A. Oren. Electronic supplementary material The online version of this article (doi:10.1007/s00792-017-0967-6) contains supplementary material, which is available to authorized users. * Laura Selbmann selbmann@unitus.it 1 Department of Ecological and Biological Sciences (DEB), University of Tuscia, Viterbo, Italy 2 Department of Agricultural, Food and Environmental Sciences, Industrial Yeasts Collection DBVPG, University of Perugia, Perugia, Italy