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Abstrakt

Candona rectangulata is an ostracod species common in cold (<15 ° C ) shallow freshwater Arctic water bodies. This species is useful in palaeolimnological studies because only few known autecological data can be applied in reconstructions of palaeoclimate. Particular attention was paid to the temperature, which is the basic factor determining the geo− graphic range of a species. In this study a wide tolerance of C. rectangulata to the temperature was demonstrated for the first time. Its high tolerance to the temperature changes seems to be based on induction of set of proteins belonging to the family of heat shock proteins. Using PAGE−SDS electrophoresis variation in the protein profile of non−model organism undergoing stress in the field (South Spitsbergen, near Stanisław Siedlecki Polish Polar Station) and in laboratory cultures was presented. These results could explain the eurythermic range of C. rectangulata and its good adaptation to the environmental conditions which normally do not exist in Arctic freshwater ponds.
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The mesostigmatid mite Vulgarogamasus immanis (Berlese, 1904) is reported in Svalbard for the first time. The gamasid mite community of Svalbard is amongst the best known of invertebrate groups of the archipelago due to recent revisions based on fresh sampling campaigns. Nonetheless, a hitherto unrecorded species of gamasid mite was recently found along the strandline in Barentsburg. This record brings the total gamasid mite inventory of Svalbard to 23 species. The current inventory of Svalbard is bedeviled with synonyms and misidentifications. Nevertheless, resolving these confusions and maintaining an accurate and updated species inventory is of prime importance in understanding the ecology of this region. Especially in a period of rapid environmental change.
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Abstrakt

Pigments (chloropigments-a and carotenoids) in sediments and macroalgae samples, collected in Hornsund, in July 2015 and July 2016, were analysed (HPLC) in this work. In spite of the aerobic conditions and the periodic intensive solar irradiation in the Arctic environment, neither of which favour pigment preservation in water column and surface sediments, our results indicate that these compounds can provide information about phytoplankton composition, primary production and environmental conditions in this region. The sum of chloropigments-a, a marker of primary production, in the Hornsund sediments varied from 0.40 to 14.97 nmol/g d.w., while the sum of carotenoids ranged from 0.58 to 8.08 nmol/g d.w. Pheophorbides-a and pyropheophorbides-a made up the highest percentage in the sum of chloropigments-a in these sediments, supplying evidence for intensive zooplankton and/or zoobenthos grazing. Among the carotenoids, fucoxanthin and its derivatives (19'-hexanoyloxyfucoxanthin and 19'-hexanoyloxy-4-ketofucoxanthin) contributed the highest percentage, which points to the occurrence mainly of diatoms and/or haptophytes in the water. The pigment markers show that the input of macroalgae to the total biomass could be considerable only in the intertidal zone.
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Abstrakt

The present contribution to lichen−forming and lichenicolous biota of northern− most Billefjorden (Petuniabukta area, central Spitsbergen, Svalbard) contains 40 species of lichens. Four species: Arthonia ligniariella, Candelariella lutella, Ochrolechia upsaliensis, Polyblastia pernigrata are new for the Svalbard Archipelago.
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Abstrakt

A 6 km long stretch of the coast of Calypsostranda between Skilvika and Josephbukta, situated on the western side of Recherchefjorden, was investigated. It is made of an accumulative marine terrace at a height of 2–8 m a.s.l. (terrace 1) and width of 40–180 m, divided by a cliffed section in the frontal moraines of Renardbreen. From the character and intensity of changes, the area was divided into 6 zones. The aim was to analyse the dynamics of changes within coastal zone from 1936 to 2007 and to characterise the influence of various morphogenetic factors (marine, fluvial, cryospheric). The important element of this study has been to determine sources and directions of sediment transport. The dynamics of changes of coastal zone in the Calypsostranda region was established from archival maps and precise GPS measurements for the periods: 1936–1960, 1960–1990, 1990–2000, 2000–2005, 2005–2006, 2006–2007. Comparing the extension of shoreline between 1936 and 2007 showed that there was more erosion than accumulation. Nearly 110 000 m 2 of the area of terrace 1 decreased, whereas about 77 000 m 2 appeared. The net balance for 1936–2007 was about −32 700 m 2 , on average over the whole length of the shoreline, it re − treated by 5.7 m (0.08 m a −1 ). The cease of sediment delivery in the extramarginal sandur fans area of Renardbreen caused intensification of marine processes, that made the shore − line retreat by over 100 m. Continuing sediment delivery from the Scottelva catchment, with contribution of material from erosion of the north end of the shoreline studies, caused the aggradation of coastal zone by over 60 m near its mouth.
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Abstrakt

Meteorological and biometeorological conditions during the warm seasons (June– September) of 1979–2008 are described for the Hornsund area, Spitsbergen. The measure− ments were taken at four sites: at Hornsund, at the Hans Glacier (at its equilibrium line and in the firn section) and at the summit of Fugleberget. The variation of meteorological and biometeorological conditions was analysed in relation to altitude, distance from the sea and the ground type. In warm seasons, the air temperature at Hornsund was 2.2 #2;C higher on aver− age than at the Hans Glacier (central section) and by 2.8 #2;C than at the Hans Glacier (firn sec− tion) and at Fugleberget. The average wind speed recorded at Hornsund was higher (0.6ms−1) than at the Hans Glacier and lower (0.9ms−1) than at Fugleberget. Four biometeorological in− dices were used: wind chill index (WCI), predicted insulation of clothing (Iclp), cooling power (H) and subjective temperature index (STI). The strongest thermal stimuli were ob− served on the Hans Glacier and in the upper mountain areas. The study has found a consider− able degree of spatial variation between the meteorological elements investigated and the biometeorological indices in the Hornsund area. The impact of atmospheric circulation on meteorological elements and biometeorological indices is also presented. The mildest bio− meteorological conditions of the warm season found at Hornsund were associated with air masses arriving from the southwest and west.
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Abstrakt

Hornsund, an Arctic fjord in the west coast of Spitsbergen (Svalbard), was selected as All Taxa Biodiversity Inventory (ATBI) site under EU 5th Framework Concerted Action BIOMARE (2000–2002), especially due to its pristine, undisturbed natural character. On the base of large material (89 stations located throughout the fjord and 129 Van Veen grab samples) collected during cruises of RV Oceania in July in 2002, 2003, 2005 and 2007 and literature search a comprehensive list of species recorded within Hornsund area, on the soft bottom with depth range of 30–250 m is provided. Over 220 species were identified including 93 species of Polychaeta, 62 species of Mollusca and 58 species of Crustacea. Species list is supported by information on the zoogeographical status, body length and biological traits of dominant species. Need for further research on Hornsund soft bottom fauna with more sampling effort is highlighted.
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Abstrakt

The thermal, anemometric and bioclimatic conditions on the topoclimatic scale were investigated in the summer season in the EbbaValley region in central Spitsbergen. Eight measurement sites, representing different ecosystems and different types of active surfaces typical of Spitsbergen, were chosen and automatic, hourly recorded, measurements were per− formed at the sites between 11 and 25 of July 2009. The analysis of the spatial distribution of the air temperature and thewind−chill temperature, both for the dayswith radiation and non−ra− diation weather, indicates that the most favorable regions in the interior of Spitsbergen are those situated in the shielded central parts of the valleys and in the lower parts of the slopes with southern exposure. The thermal and wind conditions are definitely less favorable at the tops of elevations and on the glacier. Large differences between the air temperature and the wind−chill temperature were noted, particularly during the unfavorable non−radiation weather, on the glacier and on open peaks due to a large horizontal and vertical wind−chill temperature gradient. The thermal inversions observed in the Ebba Valley in July 2009 were not of the typi− cal, glacier katabatic wind origin. They appeared during the western air circulation, which brings advection of cooled air from above the cold waters of Petunia Bay. The cold air pene− trates into the valley and pushes upwards themass of warmer air in the valley, creating a rather thin inversion layer, whose upper edge is marked with thin Stratus clouds.
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Abstrakt

This paper presents a detailed study of melting processes conducted on Hansbreen - a tidewater glacier terminating in the Hornsund fjord, Spitsbergen. The fieldwork was carried out from April to July 2010. The study included observations of meltwater distribution within snow profiles in different locations and determination of its penetration time to the glacier ice surface. In addition, the variability of the snow temperature and heat transfer within the snow cover were measured. The main objective concerns the impact of meltwater on the diversity of physical characteristics of the snow cover and its melting dynamics. The obtained results indicate a time delay between the beginning of the melting processes and meltwater reaching the ice surface. The time necessary for meltwater to percolate through the entire snowpack in both, the ablation zone and the equilibrium line zone amounted to c. 12 days, despite a much greater snow depth at the upper site. An elongated retention of meltwater in the lower part of the glacier was caused by a higher amount of icy layers (ice formations and melt-freeze crusts), resulting from winter thaws, which delayed water penetration. For this reason, a reconstruction of rain-on-snow events was carried out. Such results give new insight into the processes of the reactivation of the glacier drainage system and the release of freshwater into the sea after the winter period.
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Abstrakt

The thermal state of permafrost is a crucial indicator of environmental changes occurring in the Arctic. The monitoring of ground temperatures in Svalbard has been carried out in instrumented boreholes, although only few are deeper than 10 m and none are located in southern part of Spitsbergen. Only one of them, Janssonhaugen, located in central part of the island, provides the ground temperature data down to 100 m. Recent studies have proved that significant warming of the ground surface temperatures, observed especially in the last three decades, can be detected not only just few meters below the surface, but reaches much deeper layers. The aim of this paper is evaluation of the permafrost state in the vicinity of the Polish Polar Station in Hornsund using the numerical heat transfer model CryoGrid 2. The model is calibrated with ground temperature data collected from a 2 m deep borehole established in 2013 and then validated with data from the period 1990-2014 from five depths up to 1 m, measured routinely at the Hornsund meteorological station. The study estimates modelled ground thermal profile down to 100 m in depth and presents the evolution of the ground thermal regime in the last 25 years. The simulated subsurface temperature trumpet shows that multiannual variability in that period can reach 25 m in depth. The changes of the ground thermal regime correspond to an increasing trend of air temperatures observed in Hornsund and general warming across Svalbard.
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Abstrakt

Hornsund and Kongsfjorden are two similar-sized Arctic fjords on the West coast of Spitsbergen. They are influenced by cold coastal Arctic water (Hornsund) and warmer Atlantic water (Kongsfjorden). Environmental conditions affect the timing, quantity, spatial distribution (horizontal and vertical) of spring and summer blooms of protists as well as the taxonomic composition of those assemblages. Here, we compile published data and unpublished own measurement from the past two decades to compare the environmental factors and primary production in two fjord systems. Kongsfjorden is characterized by a deeper euphotic zone, higher biomass and greater proportion of autotrophic species. Hornsund seems to obtain more nutrients due to the extensive seabird colonies and exhibits higher turbidity compared to Kongsfjorden. The annual primary production in the analysed fjords ranges from 48 g C m-2 y-1 in Kongsfjorden to 216 g C m-2 y-1 in Hornsund, with a dominant component of microplankton (90%) followed by macrophytes and microphytobenthos.
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Abstrakt

Lacydonia (Polychaeta: Phyllodocida) is a poorly known genus containing 16 species that are sporadically collected in low densities all over the world oceans. During three cruises (in June 2014 in Ullsfjorden, northern Norway, in January 2015 in Kongsfjorden, and in June 2012 in Smeerenburg, Svalbard) nine specimens of Lacydonia eliasoni were found on sandy and muddy sediments at depths from 180 to 350 m. All specimens were incomplete and consisted of 10 to 29 chaetigers. This study presents the first record of the Lacydonia genus in the waters of Svalbard as well as the first record of L. eliasoni in coastal waters off northern Norway. This species has been reported previously in the Skagerrak and Trondheimsfjorden (southern Norway), our findings therefore may indicate a northward extension of its range, possibly due to climate changes.
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Abstrakt

Palaeomagnetic−petrographic−structural analyses of Proterozoic–Lower Palaeozoic metamorphosed carbonates from 12 locations within Oscar II Land (Western Spitsbergen) have been carried out to determine their usefulness in palaeogeographic reconstructions for Caledonian time. Structural analyses confirm that metacarbonates record several stages of deformation: D1, D2 ductile phases related to Caledonian metamorphism and a D3 brittle phase related to Late Cretaceous–Paleogene evolution of the West Spitsbergen Fold Belt. The latter is represented by thrust faults, localized folds with strain slip cleavages and late extensional collapse. Petrographic investigations reveal that Caledonian greenschist facies metamorphism was characterized by the high activity of H 2 O−CO 2 −rich fluids which promoted extensive recrystallization and within−rock spatial reorganization of sampled meta carbonates. Microscopic, SEM and microprobe analyses exclude the existence of any primary pre−metamorphic ferromagnetic minerals (primary−related to sedimentation and or early diagenesis) and point to metamorphic 4C superstructure (Fe 7 S 8 ) pyrrhotite as the main ferromagnetic carrier in investigated rocks. This is confirmed by the three−component isothermal remanent magnetization (IRM) procedures and the results of thermal demagnetizations. In 12 sites a total number of 72 independently oriented palaeomagnetic samples were collected from which 181 specimens were drilled and thermally demagnetized. Sampled metacarbonates are weakly magnetized (NRM <0.2mA/m). The statistically significant palaeomagnetic results were achieved only from 1 of 12 investigated sites. In one site situated in the Western overturned limb of the Holmesletfjellet Syncline intermediate unblocking temperatures – “pyrrhotite related” component WTSJ5M superimposed on the S1 Caledonian schistosity was recognized (D = 100.7 ° , I = −21.4 °a 95% = 5.5 ° , k = 58.23). Coincidence of WTSJ5M with Silurian–Devonian sector of the Baltica reference path after unfolding of the syncline by the angle of 130 ° suggests synfolding origin of this direction. Further, this suggests that Holmesletfjellet Syncline originated as an open fold and has been transformed into an overturned syncline during the Late Caledonian shortening or in the Late Cretaceous–Palaeogene time.
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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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Abstrakt

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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Abstrakt

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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The results from a hydrological monitoring program of Breelva basin (Spitsbergen, Svalbard) have been analysed to improve the understanding of the Werenskiöld Glacier system’s functioning in the High Arctic. Hydrographs of a 44 km 2 river basin (27 km 2 of which was covered by a glacier) were analysed for the period 2007–2012. Seasonal discharge fluctuations were linked to glacier ablation and meteorological parameters, including atmospheric circulation types. A dichotomy was found in the discharge peaks generation during the hydrologically active season, with the main role played by snow and ice melt events during its first part and the rainfall regime dominating its second part. Foehn type strong winds played a significant role in the generation of ablation type floods ( e.g. in August 2011). A simple classification of the runoff regime was applied to the examined six−year period, resulting in the identification of its three types: the ablation type (dominant in 2007 and 2009), the rainfall type (in the years 2011–2012), and the mixed type (during 2008 and 2010). According to publications the river flow season in Spitsbergen begins in June and end with freeze−up in September or at the beginning of October. Recently, this season for Breelva tend to be extended with the mid−May onset and end in the second part of October. A multiannual trend was noted that reflects a growing importance of rainfalls, especially in September. Rainfall waters play a more distinct role in outflow from the Breelva catchment recently.
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Glacierized fjords are dynamic regions, with variable oceanographic conditions and complex ice−ocean interactions, which are still poorly understood. Recent studies have shown that passive underwater acoustics offers new promising tools in this branch of polar research. Here, we present results from two field campaigns, conducted in summer 2013 and spring 2014. Several recordings with a bespoke two−hydrophone acoustic buoy were made in different parts of Hornsund Fjord, Spitsbergen in the vicinity of tidewater glaciers to study the directionality of underwater ambient noise. Representative segments of the data are used to illustrate the analyses, and determine the directions of sound sources by using the time differences of arrivals between two horizontally aligned, broadband hydrophones. The results reveal that low frequency noise (< 3 kHz) is radiated mostly from the ice cliffs, while high−frequency (> 3 kHz) noise directionality strongly depends on the distribution of floating glacial ice throughout the fjord. Changing rates of iceberg production as seen for example in field photographs and logs are, in turn, most likely linked to signal amplitudes for relevant directions. These findings demonstrate the potential offered by passive acoustics to study the dynamics of individual tidewater glaciers.
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Abstrakt

A section of a gravel−dominated coast in Isbjørnhamna (Hornsund, Svalbard) was analysed to calculate the rate of shoreline changes and explain processes controlling coastal zone development over last 50 years. Between 1960 and 2011, coastal landscape of Isbjørnhamna experienced a significant shift from dominated by influence of tide−water glacier and protected by prolonged sea−ice conditions towards storm−affected and rapidly changing coast. Information derived from analyses of aerial images and geomorphological mapping shows that the Isbjørnhamna coastal zone is dominated by coastal erosion resulting in a shore area reduction of more than 31,600 m 2 . With ~3,500 m 2 of local aggradation, the general balance of changes in the study area of the shore is negative, and amounts to a loss of more than 28,000 m 2 . Mean shoreline change is −13.1 m (−0.26 m a −1 ). Erosional processes threaten the Polish Polar Station infrastructure and may damage of one of the storage buildings in nearby future.
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Abstrakt

We present the variability of the thermal state and thickness of permafrost active layer at the raised marine beaches in Svalbard. The investigations were carried out using direct probing, thaw tube, ground temperature and radar soundings at Holocene strand plains 10–20 m a.s.l. in Fuglebergsletta (SW Spitsbergen) and at the shore of Kinnvika Bay (Nordaustlandet). Their results were compared to those obtained at other coastal sites in Svalbard. The ground temperature measurements were conducted in 2009 on August, recognized as the standard month for the maximum thawing during the last decade. The studied sites are typical for close to extreme active layer conditions on Svalbard. In Hornsund, the thawing depth exceeded 2 m, while in Kinnvika the active layer was thinner than 1 m. In Svalbard, the depth of thawing decreases generally from south to north and from the open sea coast to the central parts of islands. These differences are the consequence of diverse climatic conditions strongly determined by the radiation balance modified by a number of regional ( e.g. ocean circulation) and local ( e.g. duration of snow deposition) conditions.
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The aim of this study was to identify a suitable lichen species for the long−term monitoring of heavy−metal atmospheric pollution in Svalbard. Cladonia and Cetraria s.l. species that have been widely used until now for assessing heavy−metal deposition in the Arctic are in decline over extensive areas of Svalbard, mainly due to climate change and over−grazing by reindeer. Cetrariella delisei , rarely used for biomonitoring, is still common and widespread in this area. Levels of Cr, Ni, Fe, Cu, Pb, Zn, Cd and Mn were measured in three lichen species: Cetrariella delisei , Cladonia uncialis , Flavocetraria nivalis and in a moss Racomitrium lanuginosum from Sørkapp Land, South Spitsbergen. The results imply that Cetrariella delisei can be safely compared to Cladonia uncialis for identifying the levels of heavy metals, but direct comparison between Cetrariella delisei and other species studied is more difficult owing to differences in levels of heavy metals even in samples from the same site.
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This paper provides an overview of the results of research on changes in ground temperature down to 50 cm depth, on the Kaffiøyra Plain, Spitsbergen in the summer seasons. To achieve this, measurement data were analysed from three different ecotopes (CALM Site P2A, P2B and P2C) – a beach, a moraine and tundra – collected during 22 polar expeditions between 1975 and 2014. To ensure comparability, data sets for the common period from 21 July to 31 August (referred to as the “summer season” further in the text) were analysed. The greatest influence on temperature across the investigated ground layers comes from air temperature (correlation coefficients ranging from 0.61 to 0.84). For the purpose of the analysis of the changes in ground temperature in the years 1975–2014, missing data for certain summer seasons were reconstructed on the basis of similar data from a meteorological station at Ny-Ålesund. The ground temperature at the Beach site demonstrated a statistically−significant growing trend: at depths from 1 to 10 cm the temperature increased by 0.27–0.28 ° C per decade, and from 20 to 50 cm by as much as 0.30 ° C per decade. On the Kaffiøyra Plain, the North Atlantic Oscillation (NAO) has a greater influence on the ground an d air temperature than the Arctic Oscillation (AO).
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The aim of the study was to compare cyanobacterial and algal assemblages occurring in ornithocoprophilous habitats formed under the influence of two seabird colonies (mixed colony of piscivorous Uria lomvia and Rissa tridactyla and planktivorous Alle alle) nesting on the southwest side of Hornsund (Spitsbergen). Various influences of the bird colonies (e.g. surface trophy, treading) lead to the formation of ornithogenic habitats with quantitatively and qualitatively diverse cyanobacterial and algal assemblages. Only 6 species common to both habitats were identified, but due to their different proportions the similarity ended there. Cyanobacterial and algal assemblages of both ornithogenic habitats also react rather differently to the intensity of the bird colonies' influence. The assemblages located directly beneath piscivorous bird nests were characterized by a larger number of species, which decreased the farther from the colony it was. Cyanobacterial and algal assemblages located directly next to planktivorous bird nests were species poor, but species richness increased at locations farther from their direct influence. The obtained results confirmed that bird colonies characterized by different diet and behavior influenced the formation of two separate, quantitatively and qualitatively different cyanobacterial and algal assemblages. Species such as Eucapsis sp., Gleocapsopsis sp., Gloeothece sp., Woronichinia sp., Hematococcus sp. were characteristic for algae and cyanobacteria assemblages in the vicinity of piscivorous bird colonies, whereas Aphanocapsa sp., Gloeothece sp., Komvophoron minutum, Pseudanabaena sp., Gloeocystis sp. 2 occurred in the vicinity of planktivorous bird colonies.
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Abstrakt

The Passhatten Member (Anisian–Ladinian) is the most westward exposure of the Middle Triassic sedimentary sequence of Spitsbergen. The member has an average organic carbon of 2.21 wt %. The sediments were deposited in a shallow shelf environment under conditions of high biological productivity stimulated by a well−developed upwelling system and an enhanced nutrient supply from land areas. The high biological productivity caused a high supply of organic particles to the shelf bottom. Decomposition of organic matter initiated oxygen deficiency in the bottom waters; however, bottom water dynamics on the shallow shelf temporarily replenished the oxygen. Consequently, the Passhatten Mb section is bioturbated, even in thick black shale horizons and consists of alternately spaced lithological layers with variable organic carbon content. The organic matter is dominated by type II kerogen with a mixture of strongly altered marine and/or land derived organic matter. Calculated initial hydrogen index values suggest oil−prone organic matter similar to kerogen I and II types. The organic matter is in the upper intermediate stage of thermo−catalytic alteration, close to the cata− and metagenetic boundary. Maturity indicators including Rock−Eval, Maximum Temperature, Organic Matter Transformation Ratio, Residual Carbon content, as well as the volume of methane generated suggest mature to overmature organic matter. Methane potential retained in the black shales sequence is significant. Unexpelled gas is estimated at 395 mcf/ac−ft for the examined section.
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