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Abstrakt

Nine samples of basic (dolerite, gabbro) intrusions collected at Bellsund, South Spitsbergen, have been K−Ar dated. Three dates, between 87.8 and 102.9 Ma, obtained from dolerite sills which intrude Carboniferous and Permian deposits in Van Keulenfjorden point to a Cretaceous age of intrusive activity (Diabasodden Suite). The K−Ar dates obtained from dolerite and gabbro which intrude Upper Proterozoic metasedimentary terrane of Chamber− lindalen form two groups: the dates between 97.1 and 178.6 Ma point to a Mesozoic age of the intrusions (Diabasodden Suite); the dates from a tectonized gabbroid (280.9–402.0 Ma) might point to a Late Palaeozoic age of the intrusion. No K−Ar dates which would indicate a Proterozoic age of the basic intrusions were obtained.
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The results of the application and evaluation of the r.sun model for calculation of the total solar radiation for the Wedel Jarlsberg Land (SW Spitsbergen) are presented. Linke Turbidity Factor (LTF), which is the obligatory parameter for direct and diffused radiation calculations with the r.sun model, is derived here with the empirical formula and meteoro− logical measurements. Few different approaches for calculation of LTF are presented and tested. The r.sun model results, calculated with these various LTF, are evaluated through comparison with total solar radiation measurements gathered at Polish Polar Station. The r.sun model is found to be in good agreement with the measurements for clear sky condi− tions, with the explained variance (R2) close to 0.9. Overall, the model slightly underesti− mates the measured total radiation. Reasonable results were calculated for the cloudiness condition up to 2 octas, and for these r.sun model can be considered as a reliable and flexible tool providing spatial data on solar radiation for the study area.
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Genetic variability of two populations of Arctic freshwater crustacean Lepidurus arcticus (Crustacea, Notostraca) occuring in small tundra reservoirs near the Polish Polar Sta− tion in Hornsund (Spitsbergen) was studied. The allozyme polimorphism analysis of 11 en− zyme systems indicates a considerable distinctness and genetically heterogeneous character of the populations of L. arcticus inhabiting freshwater reservoirs of similar hydrological con− ditions situated close to each other (2 km). Our research revealed a complicated and geneti− cally heterogeneous character of the populations. Three hypotheses about genetic structure and type of reproduction were tested: hypothesis M – the free transfer without assigning a clone for particular reservoir and the lack of doublemutations; hypothesis I – separation of in− dividuals between reservoirs and the possibility of doublemutations; hypothesis S – presence of partial sexual reproduction in the population, probably with males. In conclusion participa− tion ofmales in reproduction is probable, despite their presence was not recorded in our study. Males usually occur in low numbers or not every year. The populations' clonal structure as well as the genetic diversity typical of species reproducing sexually was observed. The Hardy−Weinberg genetic equilibrium is maintained as new clonal lines appear due to the ge− netic diversity increasing incidentally as a result of sexual reproduction.
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In the southern Spitsbergen area, thermal and mineral waters are primarily associated with subpermafrost deep circulation, being mixed with shallow circulation and glacial waters. Four thermal springs, located in the region of Stormbukta (Sørkappland), were studied and analyzed. In the thermal waters, the main cation is sodium, while the main anions are chloride and bicarbonate. The temperatures of the mineral and thermal waters range from 3.4 to 15.1°C. The pH values are between 7.43 and 8.41. The total dissolved solids (TDS) content of the geothermal waters is in the range of 346–4031 mg/l and the Olsok thermal spring has the highest TDS values. Based on the variation in physicochemical characteristics, two thermal water types were distinguished in the study area. The first type is associated with thermal waters originating from deep circulation waters. The second type is associated with the thermal and mineral waters originating from the mixture of subpermfrost hot brines with glacial waters.
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Diatom assemblages from small pools and creeks on the Ecology Glacier forefield have been investigated. It is the first study in the Admiralty Bay region after the thorough taxonomic revision of the non-marine Antarctic diatom flora. A total of 122 diatom taxa, belonging to 35 genera were identified. More than 55% of all observed species have a restricted Antarctic distribution. Another 15% have a marine origin. Nitzschia gracilis Hantzsch, N. homburgiensis Lange-Bertalot and Planothidium rostrolanceolatum Van de Vijver et al. dominated the flora. Based on a DCA analysis, samples were subdivided in three groups reflecting ecological differences. Several samples (group 1) showed a mixed freshwater/marine diatom composition and are typical for coastal pools. Two other groups were separated based on the amount of limnoterrestrial taxa indicating the temporary character of some of the pools.
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In polar regions, apart from tundra and glaciers, geothermally active areas with elevated temperatures are important elements of ecosystems. One such geothermally active region characterized by mosaic ecosystems and vast areas covered by recent lava fields is Iceland. The aim of our study was to explore the diversity of invertebrates inhabiting geothermally active lava fields in the Krafla area (Iceland). Eight bryophyte samples were collected from a warm surface, mainly from the steaming areas. We have found Nematoda, Rotifera, Tardigrada and Oribatida in the samples. Habitat analysis demonstrated there to be 12 bryophyte species (five liverworts and seven mosses). The diversity of bryophytes in a single sample ranged from one to six species. The most common bryophyte was Racomitrium lanuginosum (Hedw.) Brid. Four species of tardigrades were found, including one that was new. Pilatobius islandicus sp. nov. is described herein by morphological, morphometric and molecular approaches (COI, 28S rRNA, 18S rRNA). Oribatida mites were identified as two species (Malaconothrus monodactylus (Michael, 1888) and Camisia foveolata Hammer, 1955). The average density of invertebrates was 13.1 ind./g with a maximum of 40.8 ind./g calculated per dry material. The tardigrades found in our study belonged to herbivores, microbivores and omnivores, whereas the mites belonged to saprophages, which indicates complex trophic networks in geothermally active lava fields.
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This paper constitutes the sensitivity study of application the Polar WRF model to the Svalbard area with testing selected parameterizations, including planetary boundary layer, radiation and microphysics schemes. The model was configured, using three one-way nested domains with 27 km, 9 km and 3 km grid cell resolutions. Results from the innermost domain were presented and compared against measured wind speed and air temperature at 10 meteorological stations. The study period covers two months: June 2008 and January 2009. Significant differences between simulations results occurred for planetary boundary layer (PBL) schemes in January 2009. The Mellor-Yamada-Janjic (MYJ) planetary boundary layer (PBL) scheme resulted in the lowest errors for air temperature, according to mean error (ME), mean absolute error (MAE) and correlation coefficient values, where for wind speed this scheme was the worst from all the PBL schemes tested. In the case of June 2008, shortwave and longwave radiation schemes influenced the results the most. Generally, higher correlations were obtained for January, both for air temperature and wind speed. However, the model performs better for June in terms of ME and MAE error statistics. The results were also analyzed spatially, to summarize the uncertainty of the model results related to the analyzed parameterization schemes groups. Significant variability among simulations was calculated for January 2009 over the northern part of Spitsbergen and fjords for the PBL schemes. Standard deviations for monthly average simulated values were up to 3.5°C for air temperature and around 1 m s-1 for wind speed.
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Climate change has been affecting plants over the last century and caused changes in life history features such as the flowering time. Herbarium specimens provide a snapshot of the past environmental conditions during their collection. The collection date in a herbarium specimen is a good proxy to determine the flowering period (phenology). In this study, phenological data from subarctic plant specimens collected over 100 years were gathered by using one of the largest herbarium databases in the World. The collection dates of 7146 herbarium specimens were analyzed and significant shifts in the phenology of subarctic plants were detected. In this study, most of the analyzed 142 species in a subarctic biogeographic region tended to flower earlier in the 1950–2018 period compared to the 1900–1949 as a possible result of the climate change. Flowering time shifted from 8 to 26 days in some species. Changes in flowering time may alter species interactions, community composition, and species distribution in a region. Therefore, results of this study may shed light on the possible shifts in phenology and plant responses under the climate change.
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This article aims to analyse the influence of weather types on meteorological conditions in Petuniabukta (Svalbard) during July and August of 2016. The paper analyses the daily courses of air temperature and humidity at four measurement points located on the west bank of Petuniabukta near Adam Mickiewicz University Polar Station during two different types of weather conditions: (i) cloudy and windy, (ii) calm and clear. These weather types, distinguished on the basis of wind speed and cloudiness, allowed for the creation of composite maps of the synoptic situation (SLP and geopotential height of 500 hPa distribution) and its anomalies. In the study area, the air temperature range in windy and cloudy weather conditions was larger (-10°C to 15°C) than that in sunny and calm weather (0°C to 15°C), which contrasts the range of humidity values. The diurnal cycle of meteorological elements in sunny and calm days is strongly related to the sun elevation angle. In the above-mentioned weather types, the air temperature was higher by several degrees (median 5°C to 8°C) than on windy and cloudy days (median about 0°C to 6°C) at each measurement point. On days with sunny and calm weather, a smaller vertical temperature gradient of air is observed (for sunny and calm days 0.63°C and for windy weather 0.8°C).
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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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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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Eleven species of cumaceans were found in 105 samples collected in Admiralty Bay (King George Island) in the summers of 1984/85 and 1985/86, from 20 to 500 m depth range. Four cumacean assemblages were distinguished using the multivariate analysis. They were characterized by the dominance of one or two species often with low density values. Two assemblages were found in open waters of Admiralty Bay. The first inhabited on sandy−clay−silt and silty−clay−sand bottom deposits in the depth range from 140 to 330 m, with Campylaspis maculata (1.6 ± 2.1 ind./0.1m 2 ; F = 72.4%) and Leucon sp. (1.4 ± 1.6 ind./0.1m 2 ; F = 68.9%) as key species. The second assemblage was found in the depth range from 50 to 120 m with silty−sand sediments, and it was characterized by the presence of Vauthompsonia inermis (6.5 ± 6.6 ind./0.1m 2 ; F = 92.0%). A third assemblage was found in shallow waters influenced by glaciers in the bottom area of Ezcurra Inlet. It was characterized by sandy−clay−silt sediments and the presence of Eudorella splendida (14.6 ± 9.4 ind./0.1m 2 ; F = 100.0%) as a core species. The last assemblage was found in the shallow sublittoral (50–100 m) of Ezcurra Inlet and the central basin, with Diastylis anderssoni armata (1.5 ± 1.1 ind./0.1m 2 ; F = 85.7%) and Diastylopsis goekei (1.1 ± 1.0 ind./0.1m 2 ; F = 71.4%) as the most frequent and abundant species. V. inermis is considered a eurytopic species with high frequency in the whole material, and was present in all four distinguished assemblages. E. splendida and D. goekei were also recorded in each of the assemblages, but their total frequency was lower.
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Here we report a photo−documented record of a barn swallow ( Hirundo rustica ) from the South Shetland Islands. We also review previous records of passerine vagrants in the Antarctic (south of the Antarctic Convergence Zone). This barn swallow is the first re− corded member of the Hirundinidae family on King George Island and is only the second passerine recorded in the South Shetland Islands. This sighting, along with previous records of austral negrito and austral trush represent the southernmost sightings of any passerine bird anywhere in the world.
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The occurrence and temporal variations of polar shallow groundwater systems and associated seasonal springs and seeps are studied using the example of springs and seeps in the vicinity of the eastern coast of Petuniabukta in central Spitsbergen, Svalbard. Altogether, 37 groundwater outflows were documented. The outflows were mostly located at the foot of talus slopes and were characterised by small discharges (<1 dm 3 s −1 ). The water emerging from the outflows varied widely in terms of temperature and specific electrical conductivity (SpC). These outflows were supplied mainly by water from permafrost, melting snowfields and rainfall. Daily changes were studied in four of the outflows during July 2006. The observed water discharges ranged from 0.04 to 0.7 dm 3 s −1 , and the temporal variations for the particular outflows were on the order of 50% of the average value. The water temperature amplitude for particular outflows was up to 1.5 ° C. The SpC was approximately 200 μScm −1 and increased with time by almost 40 μScm −1 in the case of two outflows drain − ing talus slopes. The water emerging from two springs in carbonate and sulphate rocks had an SpC up to 1295 μScm −1 , and in one case, its increase with time was observed to be 300 μScm −1 . The increase in the SpC with time probably reflects a decrease in the contribution of snow meltwater in the groundwater recharge. Among the major local factors affecting the groundwater outflows’ water quality and discharge rate were the following: geomorphology, rock type, meteorological conditions, state of permafrost and local water storage
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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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The fossil record of Antarctic Sphenisciformes dates as early as the late Palaeocene Cross Valley Formation, Seymour Island, Antarctic Peninsula. However, the best known Antarctic locality for early penguin remains (mainly isolated bones) is the Eocene La Meseta Formation that outcrops in the northeast of Seymour Island. The analysis of an unstudied set of specimens collected there by members of the British Antarctic Survey in 1989 has resulted in identification of a distal humerus from the unit Telm3 (early Eocene) of the formation that is the oldest known bone attributable to a medium−sized (in the context of the entire Cainozoic era) penguin. This find suggests that the origin of these birds, in con− junction with an increase in taxonomic diversity of the Eocene Sphenisciformes, was related to the Early Eocene Climatic Optimum (EECO) or, more probably, the early phase of subsequent cooling.
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Antarctic plants experience UV−B stress and for their survival they have been showing various adaptive strategies. The first line of defence is to screen UV−B radiation before it reaches the cell, then to minimize damage within the cells through other protective strategies, and finally to repair damage once it has occurred. A fifteen days experiment was designed to study lichen: Dermatocarpon sp. and Acarospora gwynnii under natural UV and below UV filter frames in the Indian Antarctic Station Maitri region of Schirmacher Oasis, East Antarctica. Changes in UV absorbing compounds, total phenolics, total carotenoids and chlorophyll content were studied. The change in total phenolics and total carotenoid content was significant in both Dermatocarpon sp. and A. gwynnii indicating that the increase in UV absorbing compounds, total phenolics and total carotenoid content act as a protective mechanism against the deleterious effect of UV−B radiations, whereas the change in chlorophyll content was not significant in both lichen species.
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In order to simulate the warming effects on Arctic wetlands, three passive open−top chambers (OTCs) and three control cage−like structures (CCSs) equipped with soil temperature and soil volumetric water content (VWC) probes for continuous micro− climatic measurements were installed in a wet hummock meadow, Petuniabukta, Billefjorden, central Spitsbergen, in 2009. The warming effects on primary productivity were investigated during summer seasons 2009 and 2010 in cyanobacterial colonies of Nostoc commune s.l., which plays an important role in the local carbon and nitrogen cycles. The microclimatic data indicated that the effect of OTCs was dependent on microtopography. During winter, two short−term snow−thaw episodes occurred, so that liquid water was available for the Nostoc communities. Because of the warming, the OTC hummock bases remained unfrozen three weeks longer in comparison to the CCSs and, in spring, the OTC hummock tops and bases exceeded 0 ° C several days earlier than CCS ones. Mean summer temperature differences were 1.6 ° C in OTC and CCS hummock tops, and 0.3 ° Cinthe OTC and CCS hummock bases. The hummock tops were drier than their bases; however the VWC difference between the OTCs and CCSs was small. Due to the only minor differences in the microclimate of OTC and CCS hummock bases, where the Nostoc colonies were located, no differences in ecophysiological characteristics of Nostoc colonies expressed as photochemistry parameters and nitrogenase activities were detected after two years exposition. Long−term monitoring of Nostoc ecophysiology in a manipulated environment is necessary for understanding their development under climate warming.
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The ability to grow clonally is generally considered important for plants in Arctic regions but analyses of clonal characteristics are lacking for entire plant communities. To fill this gap, we assessed the clonal growth of 78 plant species in the Petuniabukta region, central Spitsbergen (Svalbard), and analyzed the clonal and other life−history traits in the regional flora and plant communities with respect to environmental gradients. We distinguished five categories of clonal growth organs: perennial main roots produced by non− clonal plants, epigeogenous rhizomes, hypogeogenous rhizomes, bulbils, and stolons. Clonal growth differed among communities of the Petuniabukta region: non−clonal plants prevailed in open, early−successional communities, but clonal plants prevailed in wetlands. While the occurrence of plants with epigeogenous rhizomes was unrelated to stoniness or slope, the occurrence of plants with hypogeogenous rhizomes diminished with increasing stoniness of the substratum. Although the overall proportion of clonal plants in the flora of the Petuniabukta region was comparable to that of central Europe, the flora of the Petuniabukta region had fewer types of clonal growth organs, a slower rate of lateral spread, and a different proportion of the two types of rhizomes.
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Diurnal measurements of photosynthetic pr ocesses, effective quantum yield of photosystem II ( F PSII ), photosynthetic electron transport rate (ETR) were done in three domi− nant species of Arctic tundra ( Silene acaulis , Dryas octopetala , Salix polaris ) in Petunia− bukta, Spitsbergen. Daily courses of net photosynthesis (P N ) were calculated from chloro− phyll fluorescence data and daily photosynthesi s evaluated. The short−term field measure− ments were carried out in summer 2009, and 2010. Fluorometric parameters ( F PSII and ETR) were measured each 5 minutes as well as microc limate characteristics of the site for 10 (2009) and 8 days (2010), respectively. In all species photosynthetic ETR was well related to incident photosynthetically active radiation a nd leaf temperature. In general, D. octopetala exhibited slightly lower ETR than the other two speci es. Estimated maximu m photosynthetic rate (P Nmax ) reached 17.6, 21.4, and 22.9 μmol CO 2 m −2 s −1 for S. polaris , S. acaulis ,and D. octopetala , respectively. Daily photosynthesis reach ed comparable values in all species, D. otopetala , however, exhibited slightly lower values than the other two species both for overcast and fully sunny days (3.9 and 13.4 mmol CO 2 m −2 d −1 , respectively). The range of daily photosynthesis for S. polaris and S. acaulis studied, reached the ranges of 4.6–6.9 and 14.6–15.2 mmol CO 2 m −2 d −1 for overcast and fully sunny day, respectively.
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Determination of High Arctic regions bathymetry is strictly dependent from weather and ice mass quantity. Due to safety, it is often necessary to use a small boat to study fjords area, especially close to glaciers with unknown bathymetry. This precludes the use of modern multi−beam echosounders, and so traditional single−beam echosounders have been used for bathymetry profiling. Adequate interpolation techniques were determined for the most probable morphological formations in−between bathymetric profiles. Choosing the most accurate interpolation method allows for the determination of geographical regionalisation of submarine elevations of the Brepollen area (inner part of Hornsund, Spitsbergen). It has also been found that bathymetric interpolations should be performed on averaged grid values, rather than individual records. The Ordinary Kriging Method was identified as the most adequate for interpolations and was compared with multi beam scanning, which was possible to make due to a previously modelled single beam interpolation map. In total, eight geographical units were separated in Brepollen, based on the bathymetry, slope and aspect maps. Presented results provide a truly new image of the area, which allow for further understanding of past and present processes in the High Arctic.
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A rich collection of exceptionally preserved Lower Triassic fossil fish remains obtained during the Polish Spitsbergen Expedition of 2005 includes many isolated teeth believed to belong to a saurichthyid actinopterygian. Stable isotope analysis ( d 13 C and d 18 O) of putative Saurichthys teeth from the Hornsund area (South Spitsbergen) acting as a paleoenvironmental proxy has permitted trophic−level reconstruction and comparison with other Lower Triassic fish teeth from the same location. The broader range of d 13 C values obtained for durophagous teeth of the hybodont selachian, Lissodus , probably reflects its migratory behaviour and perhaps a greater feeding diversity. X−ray microcomputed tomography (XMT), a non−destructive technique, is used for the first time in order to elucidate de − tails of tooth histology, the results of which suggest that the method has considerable potential as a future analytical tool.
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We assessed culturable soil microfungal diversity in various habitats around Hornsund, Spitsbergen in the High Arctic, using potato dextrose agar ( PDA) medium. Thermal growth classification of the fungi obtained was determined by incubating them in 4 ° Cand 25 ° C, permitting separation of those with psychrophilic, psychrotolerant and mesophilic characteristics. In total, 68 fungal isolates were obtained from 12 soil samples, and grouped into 38 mycelial morphotypes. Intergenic spacer regions of these morphotypes were sequenced, and they represented 25 distinct taxonomic units, of which 21 showed sufficient similarity with available sequence data in NCBI to be identified to species level. Soil under ornithogenic influence showed the highest species diversity, including sequences assigned to Mortierella macrocystis, M. elongata, Mortierella sp., Cudoniella sp., Varicosporium elodeae , Beauveria bassiana , Geomyces pannorum , Penicillium sp. and Atradidymella muscivora . Fourteen taxa were classified as psychrophilic, seven mesophilic, and four psychrotolerant.
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