Diversity and species composition of diatom communities of Ardley Island, South Shetland Islands

The Antarctic diatom flora has been at the centre of interest of many studies in past decades. The present paper brings new information on the species richness, biogeography and community composition of diatoms on the Ardley Island, South Shetland Islands. One fresh-water and ten soil samples had been collected from the Antarctic Special protected area (ASPA) in the spring of 2019. The following analysis revealed eighty-six diatom taxa in well-developed communities, dominated by Luticola muticopsis, L. truncata, Pinnularia australoschoenfelderi, P. austroshetlandica and P. borealis. According to the current biogeographical knowledge, the majority of species have restricted distribution among the Antarctic Realm; 46.5% of them are reported from various islands of the Maritime Antarctic Region. Based on the dominance of species as Luticola muticopsis and L. truncata and their ecological preferences, we concluded that the species composition of the diatom communities is driven by high nutrient input from breeding seabirds and the moisture availability during the austral summer.