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Słowa kluczowe Antarctic plants fungi

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This paper recapitulates Polish botanical and mycological research on terrestrial and freshwater Antarctic ecosystems carried out between 1977 and 2009. The main results are briefly summarized. The references encompass nearly 200 papers on floristics, taxonomy, biogeography, ecology, cytology, bioc hemistry, physiology and genetics of lichens, mosses, fungi, algae and vascular plants inhabiting soils, rocks and inland waters in the Antarctic.
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There are hardly any data concerning the vertical micro−distribution of protozoa in water column in cryoconite holes on the glacier surface. Such comparisons can provide insights into the ecology of protozoa. The present research was made on Ecology Glacier (South Shetland Islands, Antarctic); vertical microzonation of c iliates in relation to physical and chemical parameters in cryoconite holes was studied. The density and biomass of protozoans significantly differed between the studied stations (cryoconite holes), with the lowest numbers in the surface water and the highest in the bottom water. The surface waters were dominated by mixotrophic and omnivorous taxa, whe reas the deepest sampling level has shown the increase of the proportion of bacterivore species . Ordination analysis indicated that TN and P−PO 4 can strongly regulate the abundance and species composition of protozoa. The redundancy analyses (RDA) showed that the ciliate communities can be separated into two groups. The first group included species associated with surface water: Halteria grandinella and Codonella sp. The second group included species that are associated with bottom water: Prorodon sp. , Holosticha pullaster , Stylonychia mytilus −complex and small scuticociliates.
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During three austral summer seasons, dust and soil from clothes, boots and equipment of members of scientific expeditions and tourists visiting the Polish Antarctic Station Henryk Arctowski were collected and analysed for the presence of fungal propagules. Of a total of 60 samples, 554 colonies of fungi belonging to 19 genera were identified. Colonies of the genus Cladosporium , Penicillium and non−sporulating fungus ( Mycelia sterilia ) dominated in the examined samples. The microbiological assessment of air for the presence of fungi was also conducted at two points in the station building and two others outside the station. A total of 175 fungal colonies belonging to six genera were isolated. Colonies of the genus Penicillium were the commonest in the air samples. The potential epidemiological consequences for indigenous species as a result of unintentional transport of fungal propagules to the Antarctic biome are discussed in the light of rapid climate change in some parts of the Ant − arctic and adaptation of fungi to extreme conditions.
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A new genus and species of heteronemertean from the Antarctic (Bellingshausen Sea), Oligodendrorhynchus hesperides , is described and illustrated. Some morphological features with major systematic significance are following: the mode of branching of the proboscis and its low number of terminal branches; the lack of horizontal lateral cephalic slits but in their place a pair of shallow epidermal depressions; a gelatinous amorphous connective stratum between the outer longitudinal and circular muscle layers; the presence of a rhynchocoelic nerve; isolated fibres of the rhynchocoel circular muscle layer interwoven with bundles of the adjacent body−wall inner longitudinal muscle fibres in the intestinal region. Other anatomical characters which can also be used to distinguish the new taxon from existing heteronemertean species that have a branched proboscis are also discussed.
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A new species of lichenized ascomycete, Massalongia olechiana Alstrup et Søchting, sp. nov. (Massalongiaceae) is described from the South Shetland Islands and the Antarctic Peninsula. The species is distinguished by laminal isidia and 5–7−septate ascospores. The relationships with the other species of the genus are discussed. From Massalongia carnosa , recorded from both the Arctic and the Antarctic, the new species is distinguished by its lack of isidioid squamules and in having pluriseptate ascospores instead of 1−septate ascospores
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Poa annua L. is the only non−native vascular plant that was successfully established in the maritime Antarctic. This project aimed to determine the amount of genetic and epigenetic variation within and between two populations of P. annua , one from South Shetland Is. (Antarctic) and the other one from Central Europe. We applied two AFLP marker systems, using endonucleases that recognised the same restriction site but differed in their sensitivity towards methylation. The Antarctic population differed from the Polish one both at the genetic and epigenetic levels. Genetic variability in the Antarctic population was lower than in the Polish one. Some loci in the Antarctic population showed signs of selection. The difference between Polish and Antarctic populations might be due to a weak bottleneck effect followed by population expansion. Using only epigenetic markers, the Ant − arctic population exhibited increased variation level compared to the Polish one. These may have resulted from plastic responses to environmental factors and could be associated with survival in extreme conditions.
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This paper offers a comparison of Muriella decolor specimens from different geographical regions and habitats (limestone caves in Poland and ice denuded areas near the Ecology Glacier, King George Island, South Shetland Islands, West Antarctic). Morphological and cytological variability, ecology and life strategies of M. decolor were studied in fresh samples, and also in cultures grown on agar plates. The complete life cycle, with de − tailed ultrastructural (LM and TEM) analysis are presented. The electron microscopic observations prove that materials identified as M. decolor collected in Poland and the Antarctic have distinct ultrastructural features. These include the chloroplast lamella arrangement, mitochondrial cristae structure and the cell wall thickness.
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The population structure, seasonal and diel changes in vertical distribution of two siphonophore species, Dimophyes arctica and Pyrostephos vanhoeffeni , in Croker Passage (Antarctic Peninsula) are examined, and compared with the results obtained by other au− thors in various oceanic areas. Zooplankton samples were taken at discrete depth intervals between 0 and 1200 m during day and night shifts, in both summer and winter seasons. Dimophyes arctica was present both in polygastric and eudoxid forms, with the latter being dominant throughout the entire study period. The results obtained demonstrate that Antarctic waters clearly enhance the reproductive ability of this species when compared with specimens from other oceanic regions. Maximum densities of Dimophyes arctica were recorded in December in the 200–400 m depth horizon. However, high concentrations of eudoxids were also recorded at deeper parts of the water column. Pyrostephos vanhoeffeni was, in contrast, most abundant in autumn and winter, and both species were found to proliferate and disperse or sink further down the water column during autumn and winter. Daily vertical migration was observed only during the summer period.
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Lichens, as typical obligate associations between lichenized fungi and their photosynthetic partners, are dominant in Antarctica. Three Antarctic lichens, Ochrolechia frigida , Umbilicaria antarctica , and Usnea aurantiaco−atra with different growth forms, were sampled nearby the Great Wall Station, King George Island. Molecular data revealed that the photosynthetic algae in these three lichens were Trebouxia jamesii . The net photo − synthesis (Pn) of three individuals from these species, together with environmental factors such as light and temperature, were recorded by CO 2 gas exchange measurements using a CI−340 portable photosynthetic system in situ . Differences between T(leaf) (the temperature of the thalli) and T(air) (the air temperature) for these lichens were not consistent, which reflected that environment and the growth form of thalli could affect T(leaf) significantly. Strong irradiation was expected to have adverse effects on Pn of Ochrolechia frigida and Umbilicaria antarctica whose thalli spread flat; but this photoinhibition had little effect on Usnea aurantiaco−atra with exuberant tufted thallus. These results indicated that photo − synthetic activity in lichens was affected by the growth forms of thalli besides microhabitat factors. One species of lichenized alga could exhibit diversified types of photosynthetic behavior when it was associated with various lichenized fungi in different microhabitats. It will be helpful for understanding how lichens are able to adapt to and colonize in extreme environments.
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Four halacarid species: Agaue agauoides, Agaue parva, Bradyagaue drygalskii, and Halacarus minor have been extracted from bottom samples taken in Admiralty Bay, King George Island, South Shetland Islands, another four, Colobocerasides auster, Halacarus arnaudi, Lohmannella fukushimai, and L. gaussi, from Kapp Norvegia, Atka and Halley Bay, Weddell Sea. Most of these species are widespread around Antarctica and adjacent islands. Diagnostic characters are outlined. An annotated list presents 66 halacarid species reported from south of the Antarctic Polar Front. © 2016 Polish Academy of Sciences 2016.
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This paper presents a complex study on ciliates from the different species of mosses of King George Island, South Shetland Islands, Antarctic. Samples of ciliates were collected from Polytrichastrum alpinum , Sanionia georgico−uncinata , Sanionia uncinata and Brachythecium austrosalebrosum . The highest species richness (19 taxa) occurred in habitats from Brachythecium austrosalebrosum . The lowest number of taxa (5) was observed in Polytrichastrum alpinum . The greatest abundance of ciliates was found in samples from Brachythecium austrosalebrosum (25–30 ind. g −1 ), while the lowest was found in samples from Polytrichastrum (4–6 ind. g −1 ). In each species of mosses, vertical differentiation of these protozoa assemblages was found. The number of species and abundance significantly increased in the lower samples. The upper samples of mosses were dominated by mixotrophic taxa, whereas samples from the lower part the proportions of bacterivore species increases. The RDA performed to specify the direct relationships between the abundance of ciliate taxa and environmental variables showed obvious differences between habitats studied. However, variables that significantly explained the variance in ciliate communities were: dissolved oxygen, pH, and nutrients.
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Between 1979 and 2007, various sampling projects from the Polish Arctowski Research Station in Admiralty Bay, King George Island, Antarctica, collected a diverse assemblage of pycnogonids, inter alia . Examination of this material has revealed 24 species in 11 genera and six families: all of this material is described. Samples were from poorly− sorted fine−sand to coarse−silt substrata, at depths between 27 and 405 m. The diverse assemblage was of species consistent with the known pycnogonid fauna of these depths in the South Shetlands and the Palmer Archipelago region, and includes a number of species re− corded for only the second time since the types. As typical for Antarctic waters, the predominant and most diverse genus was Nymphon (nine species); the prevalent species was Nymphon eltaninae , not Nymphon australe : implications for the apparent wide−distribution of records of the latter species are discussed. These records increase the biogeographical range of Nymphon subtile and Nymphon punctum from Subantarctic waters to the Scotia Sea
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Twenty six specimens of the polychaete Eulalia picta were found in finegrained sand tubes. Material was collected in the Antarctic fjord, Admiralty Bay at the depth of about 100 m. The comparison of tube sediment with the sediment composition at the collection site demonstrated that tubes were created with a high degree of particle selection. Our findings might suggest presence of the tube-building behavior in E. picta or show that this species is a highly specialized predator crawling into the tubes of other sessile polychaetes and uses their tubes as protective cases.
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The results of investigations on the coccidian parasites of three species of penguins ( Pygoscelis antarctica , P. papua and P. adeliae ), nesting at Livingston and King George Island (South Shetland Islands, the Antarctic) are presented. Three coccidian para− sites: Eimeria pygosceli Golemansky, 2003, Eimeria sp. and Isospora sp. were identified in faecal samples from 360 examined birds. The total prevalence of coccidian parasites was high: about 35% in all of examined penguins. No host specificity was observed. It is attributed due to the close phylogenetic relations, common habitats and nesting territories, similar feeding and reproductive biology of the three penguin species. In more than 20 specimens of investigated penguins a high intensity of oocysts in their guano was observed (80–220 oocysts in one microscopic field at magnification of 150×) an indirect indication of the negative role of the coccidian infections on penguin populations.
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Antarctic pearlwort ( Colobanthus quitensis ) is one of the flowering plant species considered native to maritime Antarctica. Although the species was intensively analyzed towards its morphological, anatomical and physiological adaptation to local environment, its genetic variability is still poorly studied. In the presented study, a recently developed retrotransposon−based DNA marker system (inter Primer Binding Site – iPBS) was applied to assess the genetic diversity and differentiation of C. quitensis populations from King George Island (South Shetland Islands, West Antarctic). A total of 143 scoreable bands were detected using 7 iPBS primers among 122 plant specimens representing 8 populations. 55 (38.5%) bands were found polymorphic, with an average of 14.3% polymorphic fragments per primer. Nine of all observed fragments were represented as a private bands deployed unevenly among populations. Low genetic diversity (on average H e = 0.040 and I = 0.061) and moderate population differentiation (F ST = 0.164) characterize the analyzed material. Clustering based on PCoA revealed, that the populations located on the edges of the study area diverge from the central populations. The pattern of population differentiation corresponds well with their geographic location and the characteristics of the sampling sites. Due to the character of iPBS markers, the observed genetic variability of populations may be explained by the genome rearrangements caused by mobilization of mobile genetic elements in the response to various stress factors. Additionally, this study demonstrates the usefulness of iPBS markers for genetic diversity studies in wild species.
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Phytoplankton composition plays a major role in biogeochemical cycles of the ocean. The intensity of carbon fixation and export is strongly dependent on the phytoplankton community. Yet, the contribution of different types of phytoplankton to the total production on various communities is still poorly understood in the Indian Ocean sector of Southern Ocean (SO). Therefore the variability of chlorophyll- A (Chl-a) and diatoms in the frontal ecosystems of the Indian sector of SO have been investigated along with the sea surface temperature (SST), sea surface wind (SSW), photosynthetically active radiation (PAR), and nutrients datasets for the period of 1998-2012. Combined analysis of in-situ, model and satellite observations indicate that the variability of Chl- A and diatoms were primarily influenced by light and wind. The Chl- A was higher at the sub-Antarctic front (SAF) followed by the sub-tropical front (STF) and the polar front (PF). The diatom concentration was higher at the SAF followed by the PF and STF. Maximum concentration of Chl- A and diatoms commonly observed at the SAF region are probably due to the moderate PAR, SST and wind. Dominance of diatoms at the PF may be attributed to their adaptability for low light conditions. The results from this study in the frontal ecosystems would help to understand the biogeochemical cycle of the Indian sector of the SO.
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Two new species of desmosomatid isopods, Eugerdella margaretae sp. n. and Eugerdella celata sp. n. are described from Admiralty Bay, King George Island, South Shetlands. Information is added to the original description of Eugerdella falklandica (Nordenstam, 1933) based on re−examination of the holotype. Both new species are similar to E. falklandica, for example by the body shape, the shape of pleotelson and presence of rows of four horn−like spines on the head. They are distinguished from E. falklandica by the number of setae on pereopod articles. Eugerdella celata sp. n. is distinguished by the presence of ventral spines on pereonites 1–4
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Fifteen species of isopods, representing 10 families, were recorded on holdfasts of the brown alga Himantothallus grandifolius . Material was collected in the 15–75 m depth range during the austral summer of 1979/80. The isopod community was dominated by Caecognathia antarctica (mean density 12.4 ± 13.1 ind./100 ml) followed by Cymodocella tubicauda (mean density 0.7 ± 2.1 ind./100 ml). Mean total density of isopods reached the value of 16.1 ± 14.0 ind./100 ml. The comparison with the other studies showed that hold− fasts are inhabited by a distinctive isopod community that differs from the isopod fauna associated with soft bottom of Admiralty Bay.
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The global zoogeographic distribution of the most widespread peracarid species occurring in three or more ocean basins below 2000 m is analysed. Basing on the published data we investigated 45 peracarid species, which have a most widespread distribution and most likely are cosmopolitan. Thirty−three species have a wide distribution in the Northern Hemisphere. Most species occur in the North Atlantic, however, 16 of these species occur also in the North Pacific, a more limited number of species occurs in the South Atlantic or South Pacific The Southern Ocean displays some special zoogeographic features and 22 widespread species occur there below 2000 m, including highly eurybathic ones. In total, 11 of the analysed species occur in all oceans. Eucopia australis (Lophogastrida), Munneurycope murrayi (Isopoda) and Eurythenes gryllus (Amphipoda) are the species with the widest distributions. Other peracarids occurring in all oceans are: the isopods Paramunnopsis oceanica and Eurycope sarsi , the mysid Caesaromysis hispida the lophogastrid Eucopia unguiculata, the amphipod Mesopleustes abyssorum and the tanaids Exspina typica, Paranarthura insignis and Pseudotanais nordenskioldi . No cumacean species has been reported with an ocean−wide distribution but Campylaspis glabra occurs in the Atlantic, Indian and Pacific oceans. Among plenty of rare species in each order there are only few species with wide distribution records. There is evidence from molecular genetic studies that some of the widespread peracarids represent several cryptic species, however, some, e.g. Eucopia australis , seem to be truly cosmopolitan species. Geography of sampling is biasing our view of biogeography. The history and quality of taxonomic work as well as the reliability of geographic records (quality control of large databases) limits our investigations of widespread or cosmopolitan species as much as the limited knowledge of variation within most species causes difficulties in defining morpho−species with certainty.
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This paper presents new records of stenothoids from the Scotia Arc (West Antarctic). Altogether twenty species were recorded, two of which are reported in the West Antarctic for the first time. In addition, two species are here recorded for the first time since their description. New data on distribution are supplemented by taxonomical remarks on the collected species.
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Cold−adapted marine bacteria producing extracellular hydrolytic enzymes are important for their industrial application and play a key role in degradation of particulate or ganic matter in their natural environment. In this work, members of a previously−obtained protease−producing bacterial collection isolated from different marine sources from Potter Cove (King George Island, South Shetlands) were taxonomically identified and screened for their ability to produce other economically relevant enzymes. Eighty−eight proteolytic bacterial isolates were grouped into 25 phylotypes based on their Amplified Ribosomal DNA Restriction Analysis profiles. The sequencing of the 16S rRNA genes from representative isolates of the phylotypes showed that the predominant culturable protease−producing bacteria belonged to the class Gammaproteobacteria and were affiliated to the genera Pseudomonas , Shewanella , Colwellia , and Pseudoalteromonas , the latter being the predominant group (64% of isolates). In addition, members of the classes Actinobacteria, Bacilli and Flavobacteria were found. Among the 88 isolates screened we detected producers of amylases (21), pectinases (67), cellulases (53), CM−cellulases (68), xylanases (55) and agarases (57). More than 85% of the isolates showed at least one of the extracellular enzymatic activities tested, with some of them producing up to six extracellular enzymes. Our results confirmed that using selective conditions to isolate producers of one extracellular enzyme activity increases the probability of recovering bacteria that will also produce additional extracellular enzymes. This finding establishes a starting point for future programs oriented to the prospecting for biomolecules in Antarctica.
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Our macroscopic observations and microscopic studies conducted by means of a light microscope (LM) and transmission electron microscope (TEM) concerning the reproduction biology of Colobanthus quitensis (Caryophyllaceae) growing in natural conditions in the Antarctic and in a greenhouse in Olsztyn (northern Poland) showed that this plant develops two types of bisexual flowers: opening, chasmogamous flowers and closed, cleistogamous ones. Cleistogamy was caused by a low temperature, high air humidity and strong wind. A small number of microspores differentiated in the microsporangia of C. quitensis , which is typical of cleistogamous species. Microsporocytes, and later micro − spores, formed very thick callose walls. More than twenty spheroidal, polypantoporate pollen grains differentiated in the microsporangium. They germinated on the surface of receptive cells on the dry stigma of the gynoecium or inside the microsporangium. A monosporic embryo sac of the Polygonum type differentiated in the crassinucellar ovule. During this differentiation the nucellus tissue formed and stored reserve materials. In the development of generative cells, a male germ unit (MGU) with differentiated sperm cells was observed. The smaller cell contained mainly mitochondria, and the bigger one plastids. In the process of fertilization in C. quitensis only one nucleus of the sperm cell, without cytoplasm fragments, entered the egg cell, and the proembryo developed according to the Caryophyllad type. Almost all C. quitensis ovules developed and formed perispermic seeds with a completely differentiated embryo both under natural conditions in the Antarctic and in a greenhouse in Olsztyn.
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Plants adapt to extremely low temperatures in polar regions by maximizing their photosynthetic efficiency and accumulating cryoprotective and osmoprotective compounds. Flowering plants of the family Poaceae growing in the Arctic and in the Antarctic were investigated. Their responses to cold stress were analyzed under laboratory conditions. Samples were collected after 24 h and 48 h of cold treatment. Quantitative and qualitative changes of sugars are found among different species, but they can differ within a genus of the family Poaceae. The values of the investigated parameters in Poa annua differed considerably depending to the biogeographic origin of plants. At the beginning of the experiment, Antarctic plants were acclimatized in greenhouse characterized by significantly higher content of sugars, including storage reserves, sucrose and starch, but lower total protein content. After 24 h of exposure to cold stress, much smaller changes in the examined parameters were noted in Antarctic plants than in locally grown specimens. Total sugar content and sucrose, starch and glucose levels were nearly constant in P. annua, but they varied significantly. Those changes are responsible for the high adaptability of P. annua to survive and develop in highly unsupportive environments and colonize new regions.
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A comparison between the levels of infection with Acanthocephala of the fish Notothenia coriiceps in Admiralty Bay (South Shetland Islands, Antarctic) in 1978/79 and 2007/08 is presented. The same eight acanthocephalan species, three echinorhynchids maturing in fish, Aspersentis megarhynchus (dominant species), Metacanthocephalus johnstoni (subdominant species) and M. dalmori (common species), and five polymorphids maturing in mammals and birds, Corynosoma hamanni , C. pseudohamanni (both co−dominant species), C. arctocephali and C. bullosum (both common species), and C. shackletoni (rare species), were found. Echinorhynchids were more numerous in 2007/08 (mean abundance 46.54 versus 35.35 in 1978/79), whereas polymorphids more numerous in 1978/79 (mean abundance 74.35 versus 36.40 in 2007/08). The overall results therefore demonstrated that echinorhynchids were more numerous than polymorphids in 2007/08 and the reverse was true in 1978/79. This situation is dependent mainly upon the decreased infections with C. hamanni , C. pseudohamanni and C. bullosum , and to a lesser degree upon the increasing of infections with M. johnstoni . The decrease of the three Corynosoma spp. is possibly associated with the decreasing of populations of final hosts, seals, on the shore of Admiralty Bay in the vicinity of Arctowski Station.
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Populations of Antarctic hairgrass Deschampsia antarctica Desv. from King George Island exhibit variation in many traits. The reason for that is not evident and could be addressed to variable environmental conditions. Obviously, phenotypic variation could be due to stable or temporal changes in expression pattern as the result of adaptation. Stable changes could be due to mutations or site DNA methylation variation that modified expression pattern. Recently, metAFLP approach was proposed to study such effects. A variant of methylation sensitive AFLP (Amplified Fragment Length Polymorphism), based on the isoschizomeric combinations Acc65 I/ Mse I and Kpn I/ Mse I was applied to analyze the sequence and site DNA methylation differences between two D. antarctica populations exhibiting morphological dissimilarities. Both DNA sequence mutations and site methylation pattern alternations were detected among and within analyzed populations. It is assumed that such changes might have originated as the response to environmental conditions that induced site methylation alternations leading to phenotypic variation of D. antarctica populations from South Shetland Islands.
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