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The Antarctic lichens have been used as bioindicators in biomonitoring studies, having an important contribution to the floristic composition, and its existence is dependent on ice-free regions. The phytosociological data were obtained according to the Braun-Blanquet sampling method. This study compares the lichen formation of Arctowski region, using data collected during the Brazilian Antarctic Program expedition conducted in the austral summer of 2003/2004 and 2012/2013. According to data collected at the moment, increases of the lichens occurrences in the plant formations in the region were found. Studies indicate that abiotic factors, once linked to local factors can to affect the distribution of the communities in the environment. This essay suggests the fragility of lichen formation in the ice-free areas of Arctowski region. However, a long term evaluation as necessary to confirm this hypothesis. The phytosociological studies can contribute to the management of scientific activities involved with the Brazilian Antarctic Program.

This study was undertaken in ice-free areas adjacent to the Polish Antarctic Station Henryk Arctowski, during the austral summer 2013/2014. Phytossociological surveys were made in vegetation patches in the region, where a total of 332 20x20cm quadrats were launched in 10m transects. The five most frequent species in the samples were selected and their data are presented in this work. To check the most frequent species in the samples the index of ecological significance (IES) was used. The most important species were Deschampsia antarctica Desv. and Colobanthus quitensis (Kunth) Bartl the only one angiosperms occurring in Antarctica. Sanionia uncinata (Hedw.) Loeske Politrichastrum alpinum (Hedw.) G.L.Sm. and Syntrichia magellanica (Mont.) R.H. Zander. were the most representative moss species. The data of ecological significance of these species were compared to previous results in order to evaluate the changes in the vegetation in 10 year long-time monitoring.

The distribution of fungi in Antarctica is linked to the distribution of hosts such as birds, invertebrate populations and vegetation, consisting mainly of bryophyte and lichen communities. Light is a factor which influences the growth, reproduction and physiology of fungi due to the deleterious effects of radiation released. This study aimed to evaluate the influence of light on radial mycelial growth of two species of filamentous fungi found in Antarctica: Pseudogymnoascus pannorum (Link) Minnis & D.L. Lindner and an unidentified strain growing over angiosperm Colobanthus quitensis (Kunth) Bartl. and on the moss Sanionia uncinata (Hedw.) Loeske, respectively. The collections of material for this study were conducted during the Brazilian Antarctic expedition XXXI (2012-2013). The strains were isolated in solid potato dextrose agar medium, with pH adjusted to 4 and incubated at 26±1°C. Statistical results show that the variable light influences the radial mycelial growth of these fungi.

The aim of this study has been to research the conservation status of the plant communities in ice-free areas of Ullmann Point and Comandante Ferraz Antarctic Station vicinities, Admiralty Bay, King George Island, Antarctica. The study started with the classification and description of the plant communities based primarily on phytosociological and biodiversity data. The coverage degree and frequency of each species found was used to calculate the index of ecological significance. At Ullmann Point 12 plant species were found in higher frequency, when at Ferraz beach only 9 highly frequent species were found. The most important species in both studied areas were Sanionia uncinata (Hedw.) Loeske. Syntrichia princeps and Bryum pseudotrichetrum were found associated with the most important species at Ullmann Point and Ferraz Station beach respectively. These results have demonstrated the fragility of plant communities in Maritime Antarctica, based on the low frequency and coverage of moss species known in this area.