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Background: Ice-free areas in the Antarctic region are strongly limited. The presence of marine mammals and birds in those areas influence soil properties and vegetation composition. Studies on the terrestrial diatom flora in soils influenced by sea birds in the Maritime Antarctic region are scarce., Methods: Samples were collected from two transects on the western shore of the Admiralty Bay region. Light and scanning electron microscopic observations and statistical analyses were conducted to consider the impact of penguin rookeries on soil diatom assemblages., Results: The disturbance associated with the presence of penguin rookeries clearly influences the soil diatom diversity. Assemblages from areas with the highest nutrient input were characterized by a much lower diversity with only few species dominating the flora. One of recorded taxa could not be assigned to any of the known species. Therefore, based on the combination of morphological features analyzed using light and scanning electron microscopes and comparison with similar taxa in the Antarctic region and worldwide, the species is described hereby as new to science- Luticola kaweckae sp.nov. The new species is characteristic for soil habitats with strong penguin influence., Competing Interests: The authors declare that they have no competing interests., (© 2022 Kochman-Kędziora et al.)

The present article introduces data on natural radioactivity ( 40 K, 230,232 Th, 234,238 U) in the Antarctic marine and terrestrial environment. Various biota samples were analysed due to internal exposure to 40 K, 230,232 Th, 234,238 U. Activity concentration of 40 K was the highest in both marine and terrestrial samples. Mean values of 40 K activity concentration are 1340 Bq/kg and 370 Bq/kg for the marine and terrestrial samples respectively. 234 U/ 238 U ratios analysis revealed that sea waters and sea spray are the main source of the uranium in the terrestrial samples. Average 230,232 Th, 234,238 U activity concentrations in the Antarctic biota do not exceed 6 Bq/kg. Weighted internal dose rates are relatively low; they range from approximately 0.1 to 0.6 μGy/h. Statistically significant differences in radionuclide accumulation were discovered between the mosses and lichens. It may point to various mechanisms of the nutrient absorption from the environment by these organisms., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Gaseous phase hydration properties for thalli of Niebla tigrina from Atacama Desert, and for Umbilicaria antarctica from Isla Robert, maritime Antarctica, were analyzed using 1 H-NMR relaxometry, spectroscopy, and sorption isotherm analysis. The molecular dynamics of residual water was monitored to distinguish the sequential binding very tightly, tightly, and loosely bound water fractions. These two species differ in hydration kinetics faster for Desert N. tigrina [A 1  = 0.51(4); t 1  = 0.51(5) h, t 2  = 15.0(1.9) h; total 0.7 for p/p 0  = 100%], compared to Antarctic U. antarctica [A 1  = 0.082(6), t 1  = 2.4(2) h, t 2  = [26.9(2.7)] h, total 0.6 for p/p 0  = 100%] from humid polar area. The 1 H-NMR measurements distinguish signal from tightly bound water, and two signals from loosely bound water, with different chemical shifts higher for U. antarctica than for N. tigrina. Both lichen species contain different amounts of water-soluble solid fraction. For U. antarctica, the saturation concentration of water soluble solid fraction, c s  = 0.55(9), and the dissolution effect is detected at least up to Δm/m 0  = 0.7, whereas for N. tigrina with the similar saturation concentration, c s  = 053(4), this fraction is detected up to the threshold hydration level equal to ΔM/m 0  = 0.3 only.

The article presents results of the research on artificial radionuclides ( 137 Cs, 90 Sr, 241 Am) in the Antarctic environment. Samples of 12 species from the marine environment: Pygoscelis adeliae, Pygoscelis papua, Macronectes giganteus, Pagodroma nivea, Catharacta antarctica, Leptonychotes weddellii, Mirounga leonina, Harpagifer antarcticus, Chaenocephalus aceratus, Nacella concinna, Himantothallus grandifolius, Iridaea cordata (bones, feathers, soft tissues, eggs' shells of birds, bones, skin, fur of mammals, fish, mollusks' soft tissues and shells, algae) and samples of 4 species from the terrestrial environment: Sanionia uncinata, Usnea antarctica, Usnea aurantiaco-atra, Deschampsia antarctica (mosses, lichens, grass) were investigated. Differences in the accumulation of 137 Cs between marine and terrestrial ecosystem were shown, which are mostly due to conservatism of mosses and lichens and active removal of cesium by animal body. Furthermore discrepancy between mosses and lichens in the radioceasium accumulation was statistically proven with the additional use of Neutron Activation Analysis. Moreover, the internal weighted dose rates assessment was prepared using the ERICA Tool. The dose rates were relatively low, not exceeding several dozen nGy/h. Nonetheless, one species - Pagodroma nivea, was significantly outstanding due to the highest weighted dose rate it is burdened with., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The studies of low-temperature immobilization of bound water in Antarctic lichenized fungus Turgidosculum complicatulum were performed using 1 H NMR and DSC over a wide range of thallus hydration. 1 H NMR free induction decays were decomposed into a solid component well described by the Gaussian function and two exponentially decaying components coming from a tightly bound water and from a loosely bound water fraction. 1 H NMR spectra revealed one averaged mobile proton signal component. 1 H NMR measurements recorded in time and in frequency domain suggest the non-cooperative bound water immobilization in T. complicatulum thallus. The threshold of the hydration level estimated by 1 H NMR analysis at which the cooperative bound water freezing was detected was Δm/m 0 ≈ 0.39, whereas for DSC analysis was equal to Δm/m 0 = 0.375. Main ice melting estimated from DSC measurements for zero hydration level of the sample starts at t m = -(19.29 ± 1.19)°C. However, DSC melting peak shows a composed form being a superposition of the main narrow peak (presumably melting of mycobiont areas) and a broad low-temperature shoulder (presumably melting of isolated photobiont cells). DSC traces recorded after two-hour incubation of T. complicatulum thallus at -20 °C suggest much lower threshold level of hydration at which the ice formation occurs (Δm/m 0 = 0.0842). Presumably it is a result of diffusion induced migration of separated water molecules to ice microcrystallites already present in thallus, but still beyond the calorimeter resolution., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The work includes a description of the period from the moment of setting up Polish Polar Station on King George Island (1977) to the end of International Polar Year IV in 2009. Researches on flower plants focused, among others, on plants' morphology, morphological composition of the pollen and anatomical ultra-structure of the leaves. There were also carried out biochemical and other searches for the internal mutability. Within physiological studies one concentrated on the problem of reaction to temperature stress. Biological researches focused mainly on solving taxonomic and bio-geographic problems. Finally, were published several monographs and, among others, the first in history complete description of moss' flora of the whole of Antarctic (2008). Research works over algae included also such issues as floristics, bio-geography, taxonomy and ecology (for instance, the rookery's impact on distribution of algae, or the influence of inanimate factors on dynamics of condensing the Diatoma in different water and soil-bound tanks). Up till now, within mycological investigations has been identified a variety of lichen fungi that for the most part of Antarctic are a novelty. There were scientifically described new for science genera and species of Western Antarctic. Lichenological studies were made in the field of taxonomy, geography, lichenometry, biochemistry of lichens, lichenoindication, ecophysiology and from the point of analysis of base metals' content. There were also described new for science species. Since 1991, were published the results of searches for the base metals' content and vestigial chemical elements in lichens' thallus. Ecophysiological researches concerned both micro-climatic conditions' impact on primary production and lichens' adaptation to a very cold climate. One discovered a mechanism of two-phase hydratization/dehydratization of lichens' thallus. On the ground of palaeobotanical analyzes was reconstructed a development of flora in Western Antarctic from the late Cretaceous period to the beginning of Melville's continental glaciation. One singled out three floristic stages and were reconstructed their peculiarities in the development of flora. There was also described an early Jurassic flora of Hope Bay (Półwysep Antarktyczny - Antarctic Peninsula) that turned out to be the richest Jurassic flora in the world. From that point of view were analyzed new species of mineral plants. Ecological researches concentrated on the problems connected with several issues and, among others, with the processes of settlement and succession, distribution and ecology of land biotopes, changes in their spatial structure, and state of biotopes' biological mass. The second group of issues concerned the anthropogenous impacts. One also analyzed early stages of synanthropization of flora. Another important issue was recognizing an extent of the pollution of the environment, particularly with base metals. In the years 1977-2009 were published, at least, 426 notes, articles and monographs that were a result of botanical and mycological researches on sheets of land of Antarctic and Sub-Antarctic.

The genetic diversity of all available culture strains of the Tribonemataceae (Stramenopiles, Xanthophyceae) from Antarctica was assessed using the chloroplast-encoded psbA /rbcL spacer region sequences, a highly variable molecular marker, to test for endemism when compared with their closest temperate relatives. There was no species endemic for Antarctica, and no phylogenetic clade corresponded to a limited geographical region. However, species of the Tribonemataceae may have Antarctic populations that are distinct from those of other regions because the Antarctic strain spacer sequences were not identical to sequences from temperate regions. Spacer sequences from five new Antarctic isolates were identical to one or more previously available Antarctic strains, indicating that the Tribonemataceae diversity in Antarctic may be rather limited. Direct comparisons of the spacer sequences and phylogenetic analyses of the more conserved rbcL gene revealed that current morphospecies were inadequate to describe the actual biodiversity of the group. For example, the genus Xanthonema, as currently circumscribed, was paraphyletic. Fortunately, the presence of distinctive sequence regions within the psbA/rbcL spacer, together with differences in the rbcL phylogeny, provided significant autoapomorphic criteria to re-define the Tribonemataceae species.