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Rasmus Dyrmose Nørregaard, Mai Dang, Lis Bach, Ole Geertz-Hansen, Kim Gustavson, Peter Aastrup, Pall S Leifsson, Jens Søndergaard, Barbara Nowak, Christian Sonne
The former lead-zinc mine at Mestersvig, Greenland, continues to contaminate the surrounding environment despite its operations ceasing over 50 years ago. Elevated concentrations of heavy metals are found in water, sediment and biota in the terrestrial, freshwater and marine environments. To shed light on the present contamination and its potential effects on local fish we investigated gill and liver histology of sculpins (Myoxocephalus spp.) around the former mining area. Two species of sculpins were caught; shorthorn sculpins (M...
May 16, 2018: Environmental Research
Wendy C Andersen, Christine R Casey, Tara J Nickel, Susan L Young, Sherri B Turnipseed
Background : Triphenylmethane dyes and metabolites are known or suspected mutagens and areprohibited in animals intended for human consumption. Despite toxicity, triphenylmethane dyes are used illegally as inexpensive treatments for fungal and parasite infections in aquatic animals. Objective: AOAC INTERNTIONAL Official Method ℠ 2012.25 for the LC-MS/MS determination of malachite green, crystal violet, brilliant green, and metabolites leucomalachite green and leucocrystal violet in seafood products was previously validated for finfish (trout, salmon, catfish, and tilapia) and shrimp, but had not been fully validated for other types of aquacultured products such as eel, molluscan shellfish, or frog or for processed seafoods...
May 18, 2018: Journal of AOAC International
Norman Gentsch, Birgit Wild, Robert Mikutta, Petr Čapek, Katka Diáková, Marion Schrumpf, Stephanie Turner, Cynthia Minnich, Frank Schaarschmidt, Olga Shibistova, Jörg Schnecker, Tim Urich, Antje Gittel, Hana Šantrůčková, Jiři Bárta, Nikolay Lashchinskiy, Roland Fuß, Andreas Richter, Georg Guggenberger
Climate change in Arctic ecosystems fosters permafrost thaw and makes massive amounts of ancient soil organic carbon (OC) available to microbial breakdown. However, fractions of the organic matter (OM) may be protected from rapid decomposition by their association with minerals. Little is known about the effects of mineral-organic associations (MOA) on the microbial accessibility of OM in permafrost soils and it is not clear which factors control its temperature sensitivity. In order to investigate if and how permafrost soil OC turnover is affected by mineral controls, the heavy fraction (HF) representing mostly MOA was obtained by density fractionation from 27 permafrost soil profiles of the Siberian Arctic...
May 18, 2018: Global Change Biology
J E Wollenburg, C Katlein, G Nehrke, E-M Nöthig, J Matthiessen, D A Wolf-Gladrow, A Nikolopoulos, F Gázquez-Sanchez, L Rossmann, P Assmy, M Babin, F Bruyant, M Beaulieu, C Dybwad, I Peeken
Mineral ballasting enhances carbon export from the surface to the deep ocean; however, little is known about the role of this process in the ice-covered Arctic Ocean. Here, we propose gypsum ballasting as a new mechanism that likely facilitated enhanced vertical carbon export from an under-ice phytoplankton bloom dominated by the haptophyte Phaeocystis. In the spring 2015 abundant gypsum crystals embedded in Phaeocystis aggregates were collected throughout the water column and on the sea floor at a depth below 2 km...
May 16, 2018: Scientific Reports
Amanda M Koltz, Niels M Schmidt, Toke T Høye
The Arctic is experiencing some of the fastest rates of warming on the planet. Although many studies have documented responses to such warming by individual species, the idiosyncratic nature of these findings has prevented us from extrapolating them to community-level predictions. Here, we leverage the availability of a long-term dataset from Zackenberg, Greenland (593 700 specimens collected between 1996 and 2014), to investigate how climate parameters influence the abundance of different arthropod groups and overall community composition...
April 2018: Royal Society Open Science
Karsten Hueffer, Molly Murphy
Rabies is a serious zoonotic disease with significant public health consequences in the circumpolar North. Recent studies have advanced our understanding of the disease ecology in Alaska. In this paper, we review historical records of rabies in Alaska ranging from the late nineteenth century to the present, analyse the public health impact in the state and review studies on disease ecology before assessing challenges and anticipated altered disease dynamics in the face of a rapidly changing North. Rabies is a disease that has been present in Alaska continuously for over 100 years...
December 2018: International Journal of Circumpolar Health
Joseph R McConnell, Andrew I Wilson, Andreas Stohl, Monica M Arienzo, Nathan J Chellman, Sabine Eckhardt, Elisabeth M Thompson, A Mark Pollard, Jørgen Peder Steffensen
Lead pollution in Arctic ice reflects midlatitude emissions from ancient lead-silver mining and smelting. The few reported measurements have been extrapolated to infer the performance of ancient economies, including comparisons of economic productivity and growth during the Roman Republican and Imperial periods. These studies were based on sparse sampling and inaccurate dating, limiting understanding of trends and specific linkages. Here we show, using a precisely dated record of estimated lead emissions between 1100 BCE and 800 CE derived from subannually resolved measurements in Greenland ice and detailed atmospheric transport modeling, that annual European lead emissions closely varied with historical events, including imperial expansion, wars, and major plagues...
May 14, 2018: Proceedings of the National Academy of Sciences of the United States of America
Aaron M Jubb, Jeremy R Eskelsen, Xiangping Yin, Jianqiu Zheng, Michael J Philben, Eric M Pierce, David E Graham, Stan D Wullschleger, Baohua Gu
Massive amounts of organic carbon have accumulated in Arctic permafrost and soils due to anoxic and low temperature conditions that limit aerobic microbial respiration. Alternative electron acceptors are thus required for microbes to degrade organic carbon in these soils. Iron or iron oxides have been recognized to play an important role in carbon cycle processes in Arctic soils, although the exact form and role as an electron acceptor or donor remain poorly understood. Here, Arctic biofilms collected during the summers of 2016 and 2017 from tundra surface waters on the Seward Peninsula of western Alaska were characterized with a suite of microscopic and spectroscopic methods...
August 15, 2018: Science of the Total Environment
Venke Kristoffersen, Teppo Rämä, Johan Isaksson, Jeanette Hammer Andersen, William H Gerwick, Espen Hansen
The marine environment is a rich source of biodiversity, including microorganisms that have proven to be prolific producers of bioactive secondary metabolites. Arctic seas are less explored than warmer, more accessible areas, providing a promising starting point to search for novel bioactive compounds. In the present work, an Arctic marine Pseudomonas sp. belonging to the Pseudomonas (P.) fluorescence group was cultivated in four different media in an attempt to activate biosynthetic pathways leading to the production of antibacterial and anticancer compounds...
May 14, 2018: Marine Drugs
Eric Blomgren, Jenny C Hesson, Martina L Schäfer, Jan O Lundström
Major nuisance species are found among the floodwater mosquitoes and snow-pool mosquitoes, with the former being the main reason for mosquito control in most areas. Nuisance species vary with the area, and previous reports from northern areas conclude that the nuisance is most often caused by snow-pool mosquitoes. We investigated the mosquito fauna and abundances of host-seeking females using CDC traps baited with carbon dioxide, in Övertorneå city near the Arctic Circle in northern Sweden, after earlier complaints about massive mosquito nuisance...
June 2018: Journal of Vector Ecology: Journal of the Society for Vector Ecology
Pia Steinrücken, Svein A Mjøs, Siv K Prestegard, Svein R Erga
Microalgae with a high content of the omega-3 polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) are of great demand for microalgae-based technologies. An Arctic strain of the diatom Attheya septentrionalis was shown in previous experiments to increase its EPA content from 3.0 to 4.6% of dry weight (DW) in the nutrient-replete exponential phase and nutrient-depleted stationary phase, respectively. In the present study, a factorial-design experiment was used, to investigate this effect in more detail and in combination with varying salinities and irradiances...
2018: Frontiers in Plant Science
Klaus Dethloff, Dörthe Handorf, Ralf Jaiser, Annette Rinke, Pia Klinghammer
The Arctic has become a hot spot of climate change, but the nonlinear interactions between regional and global scales in the coupled climate system responsible for Arctic amplification are not well understood and insufficiently described in climate models. Here, we compare reanalysis data with model simulations for low and high Arctic sea ice conditions to identify model biases with respect to atmospheric Arctic-mid-latitude linkages. We show that an appropriate description of Arctic sea ice forcing is able to reproduce the observed winter cooling in mid-latitudes as result of improved tropospheric-stratospheric planetary wave propagation triggering a negative phase of the Arctic Oscillation/North Atlantic Oscillation in late winter...
May 12, 2018: Annals of the New York Academy of Sciences
Jøran Solnes Skaar, Erik Magnus Ræder, Jan Ludvig Lyche, Lutz Ahrens, Roland Kallenborn
A combination of local (i.e. firefighting training facilities) and remote sources (i.e. long-range transport) is assumed to be responsible for the occurrence of per- and polyfluoroalkyl substances (PFASs) in Svalbard (Norwegian Arctic). However, no systematic elucidation of local PFASs sources has been conducted yet. Therefore, a survey was performed aiming at identifying local PFAS pollution sources on the island of Spitsbergen (Svalbard, Norway). Soil, freshwater (lake, draining rivers), seawater, meltwater run-off, surface snow and coastal sediment samples were collected from Longyearbyen (Norwegian mining town), Ny-Ålesund (research facility) and the Lake Linnévatnet area (background site) during several campaigns (2014-2016) and analysed for 14 individual target PFASs...
May 12, 2018: Environmental Science and Pollution Research International
Dovilė Barcytė, Ladislav Hodač, Linda Nedbalová, Josef Elster
The traditional green algal genus Chloromonas accommodates mesophilic, cold-tolerant and cold-adapted microorganisms. In this paper we studied a new strain isolated from a wet hummock meadow in the High Arctic. We used morphological, ultrastructural and molecular data to assess the taxonomic position and phylogenetic relationships of the new isolate. The observed morphological features generally corresponded to the cold-tolerant Chloromonas characteristics. However, ellipsoidal or wide ellipsoidal vegetative cells, a massive parietal cup-shaped chloroplast with a number of continuously connected lobes, a thick cell wall, a prominent hemispherical papilla and the anterior position of an oblong or round eyespot distinguished the alga from all previously described Chloromonas species...
May 12, 2018: Journal of Eukaryotic Microbiology
Qing Mu, Manabu Shiraiwa, Mega Octaviani, Nan Ma, Aijun Ding, Hang Su, Gerhard Lammel, Ulrich Pöschl, Yafang Cheng
Polycyclic aromatic hydrocarbons like benzo( a )pyrene (BaP) in atmospheric particulate matter pose a threat to human health because of their high carcinogenicity. In the atmosphere, BaP is mainly degraded through a multiphase reaction with ozone, but the fate and atmospheric transport of BaP are poorly characterized. Earlier modeling studies used reaction rate coefficients determined in laboratory experiments at room temperature, which may overestimate/underestimate degradation rates when applied under atmospheric conditions...
March 2018: Science Advances
Alex C Y Yeung
No abstract text is available yet for this article.
May 2018: Nature
Marc Macias-Fauria, Eric Post
No abstract text is available yet for this article.
May 2018: Biology Letters
Niels M Schmidt, Jesper B Mosbacher, Bernhard Eitzinger, Eero J Vesterinen, Tomas Roslin
Mammal herbivores may exert strong impacts on plant communities, and are often key drivers of vegetation composition and diversity. We tested whether such mammal-induced changes to a high Arctic plant community are reflected in the structure of other trophic levels. Specifically, we tested whether substantial vegetation changes following the experimental exclusion of muskoxen ( Ovibos moschatus ) altered the composition of the arthropod community and the predator-prey interactions therein. Overall, we found no impact of muskox exclusion on the arthropod community: the diversity and abundance of both arthropod predators (spiders) and of their prey were unaffected by muskox presence, and so was the qualitative and quantitative structure of predator-prey interactions...
May 2018: Biology Letters
Aida Sarmiento-Vizcaíno, Julia Espadas, Jesús Martín, Alfredo F Braña, Fernando Reyes, Luis A García, Gloria Blanco
A cultivation-dependent approach revealed that highly diverse populations of Streptomyces were present in atmospheric precipitations from a hailstorm event sampled in February 2016 in the Cantabrian Sea coast, North of Spain. A total of 29 bioactive Streptomyces strains isolated from small samples of hailstone and rainwater, collected from this hailstorm event, were studied here. Taxonomic identification by 16S rRNA sequencing revealed more than 20 different Streptomyces species, with their closest homologs displaying mainly oceanic but also terrestrial origins...
2018: Frontiers in Microbiology
Benedetta Turchetti, Laura Selbmann, Nina Gunde-Cimerman, Pietro Buzzini, José Paulo Sampaio, Polona Zalar
Over 80% of the Earth’s environments are permanently or periodically exposed to temperatures below 5 °C. Cold habitats harbour a wide diversity of psychrophilic and psychrotolerant yeasts. During ecological studies of yeast communities carried out in cold ecosystem in the Italian Alps, Svalbard (Norway, Arctic region), and Portugal, 23 yeast strains that could not be assigned to any known fungal taxa were isolated. In particular, two of them were first identified as Rhodotorula sp., showing the highest degree of D1/D2 sequence identity with Cystobasidum laryngis accounted to only 97% with the type strain ( C...
May 5, 2018: Life
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