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Sample records for arctic marine food

  1. Trophic transfer of contaminants in a changing arctic marine food web: Cumberland Sound, Nunavut, Canada.

    Science.gov (United States)

    McKinney, Melissa A; McMeans, Bailey C; Tomy, Gregg T; Rosenberg, Bruno; Ferguson, Steven H; Morris, Adam; Muir, Derek C G; Fisk, Aaron T

    2012-09-18

    Contaminant dynamics in arctic marine food webs may be impacted by current climate-induced food web changes including increases in transient/subarctic species. We quantified food web organochlorine transfer in the Cumberland Sound (Nunavut, Canada) arctic marine food web in the presence of transient species using species-specific biomagnification factors (BMFs), trophic magnification factors (TMFs), and a multifactor model that included δ(15)N-derived trophic position and species habitat range (transient versus resident), and also considered δ(13)C-derived carbon source, thermoregulatory group, and season. Transient/subarctic species relative to residents had higher prey-to-predator BMFs of biomagnifying contaminants (1.4 to 62 for harp seal, Greenland shark, and narwhal versus 1.1 to 20 for ringed seal, arctic skate, and beluga whale, respectively). For contaminants that biomagnified in a transient-and-resident food web and a resident-only food web scenario, TMFs were higher in the former (2.3 to 10.1) versus the latter (1.7 to 4.0). Transient/subarctic species have higher tissue contaminant levels and greater BMFs likely due to higher energetic requirements associated with long-distance movements or consumption of more contaminated prey in regions outside of Cumberland Sound. These results demonstrate that, in addition to climate change-related long-range transport/deposition/revolatilization changes, increasing numbers of transient/subarctic animals may alter food web contaminant dynamics.

  2. Trophic transfer of contaminants in a changing arctic marine food web: Cumberland Sound, Nunavut, Canada.

    Science.gov (United States)

    McKinney, Melissa A; McMeans, Bailey C; Tomy, Gregg T; Rosenberg, Bruno; Ferguson, Steven H; Morris, Adam; Muir, Derek C G; Fisk, Aaron T

    2012-09-18

    Contaminant dynamics in arctic marine food webs may be impacted by current climate-induced food web changes including increases in transient/subarctic species. We quantified food web organochlorine transfer in the Cumberland Sound (Nunavut, Canada) arctic marine food web in the presence of transient species using species-specific biomagnification factors (BMFs), trophic magnification factors (TMFs), and a multifactor model that included δ(15)N-derived trophic position and species habitat range (transient versus resident), and also considered δ(13)C-derived carbon source, thermoregulatory group, and season. Transient/subarctic species relative to residents had higher prey-to-predator BMFs of biomagnifying contaminants (1.4 to 62 for harp seal, Greenland shark, and narwhal versus 1.1 to 20 for ringed seal, arctic skate, and beluga whale, respectively). For contaminants that biomagnified in a transient-and-resident food web and a resident-only food web scenario, TMFs were higher in the former (2.3 to 10.1) versus the latter (1.7 to 4.0). Transient/subarctic species have higher tissue contaminant levels and greater BMFs likely due to higher energetic requirements associated with long-distance movements or consumption of more contaminated prey in regions outside of Cumberland Sound. These results demonstrate that, in addition to climate change-related long-range transport/deposition/revolatilization changes, increasing numbers of transient/subarctic animals may alter food web contaminant dynamics. PMID:22957980

  3. Trophodynamics of some PFCs and BFRs in a western Canadian Arctic marine food web.

    Science.gov (United States)

    Tomy, Gregg T; Pleskach, Kerri; Ferguson, Steve H; Hare, Jonathon; Stern, Gary; Macinnis, Gordia; Marvin, Chris H; Loseto, Lisa

    2009-06-01

    The trophodynamics of per- and polyfluorinated compounds and bromine-based flame retardants were examined in components of a marine food web from the western Canadian Arctic. The animals studied and their relative trophic status in the food web, established using stable isotopes of nitrogen (delta15N), were beluga (Delphinapterus leucas) > ringed seal (Phoca hispida) > Arctic cod (Boreogadus saida) > Pacific herring (Clupea pallasi) approximately equal to Arctic cisco (Coregonus autumnalis) > pelagic amphipod (Themisto libellula) > Arctic copepod (Calanus hyperboreus). For the brominated diphenyl ethers, the lipid adjusted concentrations of the seven congeners analyzed (Sigma7BDEs: -47, -85, -99, -100, -153, -154, and -209) ranged from 205.4 +/- 52.7 ng/g in Arctic cod to 2.6 +/- 0.4 ng/g in ringed seals. Mean Sigma7BDEs concentrations in Arctic copepods, 16.4 ng/g (n = 2, composite sample), were greater than those in the top trophic level (TL) marine mammals and suggests that (i) Arctic copepods are an important dietary component that delivers BDEs to the food web and (ii) because these compounds are bioaccumulative, metabolism and depletion of BDE congeners in top TL mammals is an important biological process. There were differences in the concentration profiles of the isomers of hexabromocyclododecane (HBCD) in the food web. The most notable difference was observed for beluga, where the alpha-isomer was enriched (accounting for approximately 90% of the SigmaHBCD body burden), relative to its primary prey species, Arctic cod, where the alpha-isomer accounted for only 20% of the SigmaHBCD body burden (beta: 4% and gamma: 78%). For the C8-C11 perfluorinated carboxylic acids, the trophic magnification factors (TMFs) were all greater than unity and increased with increasing carbon chain length. PFOS and its neutral precursor, PFOSA, also had TMF values greater than one. There were also pronounced differences in the PFOSA to PFOS ratio in ringed seal (0.04) and in

  4. Defining ecospace of Arctic marine food webs using a novel quantitative approach

    Science.gov (United States)

    Gale, M.; Loseto, L. L.

    2011-12-01

    The Arctic is currently facing unprecedented change with developmental, physical and climatological changes. Food webs within the marine Arctic environment are highly susceptible to anthropogenic stressors and have thus far been understudied. Stable isotopes, in conjunction with a novel set of metrics, may provide a framework that allows us to understand which areas of the Arctic are most vulnerable to change. The objective of this study was to use linear distance metrics applied to stable isotopes to a) define and quantify four Arctic marine food webs in ecospace; b) enable quantifiable comparisons among the four food webs and with other ecosystems; and, c) evaluate vulnerability of the four food webs to anthropogenic stressors such as climate change. The areas studied were Hudson Bay, Beaufort Sea, Lancaster Sound and North Water Polynya. Each region was selected based on the abundance of previous research and published and available stable isotope data in peer-review literature. We selected species to cover trophic levels ranging from particulate matter to polar bears with consideration of pelagic, benthic and ice-associated energy pathways. We interpret higher diversity in baseline carbon energy as signifying higher stability in food web structure. Based on this, the Beaufort Sea food web had the highest stability; the Beaufort Sea food web occupied the largest isotopic niche space and was supported by multiple carbon sources. Areas with top-down control system, such as Lancaster Sound and North Water Polynya, would be the first to experience an increase in trophic redundancy and possible hardships from external stressors, as they have fewer basal carbon sources and greater numbers of mid-high level consumers. We conclude that a diverse carbon energy based ecosystem such as the Beaufort Sea and Hudson Bay regions are more resilient to change than a top down control system.

  5. Trophic transfer of persistent organochlorine contaminants (OCs) within an Arctic marine food web from the southern Beaufort-Chukchi Seas

    International Nuclear Information System (INIS)

    The trophic status and biomagnification of persistent OCs within the near-shore Beaufort-Chukchi Seas food web from Barrow, AK is discussed. - Stable isotope values (δ13C, δ15N) and concentrations of persistent organochlorine contaminants (OCs) were determined to evaluate the near-shore marine trophic status of biota and biomagnification of OCs from the southern Beaufort-Chukchi Seas (1999-2000) near Barrow, AK. The biota examined included zooplankton (Calanus spp.), fish species such as arctic cod (Boreogadus saida), arctic char (Salvelinus alpinus), pink salmon (Oncorhynchus gorbuscha), and fourhorn sculpin (Myoxocephalus quadricornis), along with marine mammals, including bowhead whales (Balaena mysticetus), beluga whales (Delphinapterus leucas), ringed seals (Phoca hispida) and bearded seals (Erignathus barbatus). The isotopically derived trophic position of biota from the Beaufort-Chukchi Seas marine food web, avian fauna excluded, is similar to other coastal food webs in the Arctic. Concentrations of OCs in marine mammals were significantly greater than in fish and corresponded with determined trophic level. In general, OCs with the greatest food web magnification factors (FWMFs) were those either formed due to biotransformation (e.g. p,p'-DDE, oxychlordane) or considered recalcitrant (e.g. β-HCH, 2,4,5-Cl substituted PCBs) in most biota, whereas concentrations of OCs that are considered to be readily eliminated (e.g. γ-HCH) did not correlate with trophic level. Differences in physical-chemical properties of OCs, feeding strategy and possible biotransformation were reflected in the variable biomagnification between fish and marine mammals. The FWMFs in the Beaufort-Chukchi Seas region were consistent with reported values in the Canadian Arctic and temperate food webs, but were statistically different than FWMFs from the Barents and White Seas, indicating that the spatial variability of OC contamination in top-level marine Arctic predators is attributed to

  6. Trophic transfer of persistent organochlorine contaminants (OCs) within an Arctic marine food web from the southern Beaufort-Chukchi Seas

    Energy Technology Data Exchange (ETDEWEB)

    Hoekstra, P.F.; O' Hara, T.M.; Fisk, A.T.; Borgaa, K.; Solomon, K.R.; Muir, D.C.G

    2003-08-01

    The trophic status and biomagnification of persistent OCs within the near-shore Beaufort-Chukchi Seas food web from Barrow, AK is discussed. - Stable isotope values ({delta}{sup 13}C, {delta}{sup 15}N) and concentrations of persistent organochlorine contaminants (OCs) were determined to evaluate the near-shore marine trophic status of biota and biomagnification of OCs from the southern Beaufort-Chukchi Seas (1999-2000) near Barrow, AK. The biota examined included zooplankton (Calanus spp.), fish species such as arctic cod (Boreogadus saida), arctic char (Salvelinus alpinus), pink salmon (Oncorhynchus gorbuscha), and fourhorn sculpin (Myoxocephalus quadricornis), along with marine mammals, including bowhead whales (Balaena mysticetus), beluga whales (Delphinapterus leucas), ringed seals (Phoca hispida) and bearded seals (Erignathus barbatus). The isotopically derived trophic position of biota from the Beaufort-Chukchi Seas marine food web, avian fauna excluded, is similar to other coastal food webs in the Arctic. Concentrations of OCs in marine mammals were significantly greater than in fish and corresponded with determined trophic level. In general, OCs with the greatest food web magnification factors (FWMFs) were those either formed due to biotransformation (e.g. p,p'-DDE, oxychlordane) or considered recalcitrant (e.g. {beta}-HCH, 2,4,5-Cl substituted PCBs) in most biota, whereas concentrations of OCs that are considered to be readily eliminated (e.g. {gamma}-HCH) did not correlate with trophic level. Differences in physical-chemical properties of OCs, feeding strategy and possible biotransformation were reflected in the variable biomagnification between fish and marine mammals. The FWMFs in the Beaufort-Chukchi Seas region were consistent with reported values in the Canadian Arctic and temperate food webs, but were statistically different than FWMFs from the Barents and White Seas, indicating that the spatial variability of OC contamination in top

  7. Seasonal variation in accumulation of persistent organic pollutants in an Arctic marine benthic food web.

    Science.gov (United States)

    Evenset, A; Hallanger, I G; Tessmann, M; Warner, N; Ruus, A; Borgå, K; Gabrielsen, G W; Christensen, G; Renaud, P E

    2016-01-15

    The aim of the present study was to investigate seasonal variation in persistent organic pollutant (POP) concentrations, as well as food-web biomagnification, in an Arctic, benthic marine community. Macrozoobenthos, demersal fish and common eiders were collected both inside and outside of Kongsfjorden, Svalbard, during May, July and October 2007. The samples were analysed for a selection of legacy chlorinated POPs. Overall, low levels of POPs were measured in all samples. Although POP levels and accumulation patterns showed some seasonal variation, the magnitude and direction of change was not consistent among species. Overall, seasonality in bioaccumulation in benthic biota was less pronounced than in the pelagic system in Kongsfjorden. In addition, the results indicate that δ(15)N is not a good predictor for POP-levels in benthic food chains. Other factors, such as feeding strategy (omnivory, necrophagy versus herbivory), degree of contact with the sediment, and a high dependence on particulate organic matter (POM), with low POP-levels and high δ(15)N-values (due to bacterial isotope enrichment), seem to govern the uptake of the different POPs and result in loads deviating from what would be expected consulting the trophic position alone. PMID:26519572

  8. Tracing carbon flow in an arctic marine food web using fatty acid-stable isotope analysis.

    Science.gov (United States)

    Budge, S M; Wooller, M J; Springer, A M; Iverson, S J; McRoy, C P; Divoky, G J

    2008-08-01

    Global warming and the loss of sea ice threaten to alter patterns of productivity in arctic marine ecosystems because of a likely decline in primary productivity by sea ice algae. Estimates of the contribution of ice algae to total primary production range widely, from just 3 to >50%, and the importance of ice algae to higher trophic levels remains unknown. To help answer this question, we investigated a novel approach to food web studies by combining the two established methods of stable isotope analysis and fatty acid (FA) analysis--we determined the C isotopic composition of individual diatom FA and traced these biomarkers in consumers. Samples were collected near Barrow, Alaska and included ice algae, pelagic phytoplankton, zooplankton, fish, seabirds, pinnipeds and cetaceans. Ice algae and pelagic phytoplankton had distinctive overall FA signatures and clear differences in delta(13)C for two specific diatom FA biomarkers: 16:4n-1 (-24.0+/-2.4 and -30.7+/-0.8 per thousand, respectively) and 20:5n-3 (-18.3+/-2.0 and -26.9+/-0.7 per thousand, respectively). Nearly all delta(13)C values of these two FA in consumers fell between the two stable isotopic end members. A mass balance equation indicated that FA material derived from ice algae, compared to pelagic diatoms, averaged 71% (44-107%) in consumers based on delta(13)C values of 16:4n-1, but only 24% (0-61%) based on 20:5n-3. Our estimates derived from 16:4n-1, which is produced only by diatoms, probably best represented the contribution of ice algae relative to pelagic diatoms. However, many types of algae produce 20:5n-3, so the lower value derived from it likely represented a more realistic estimate of the proportion of ice algae material relative to all other types of phytoplankton. These preliminary results demonstrate the potential value of compound-specific isotope analysis of marine lipids to trace C flow through marine food webs and provide a foundation for future work. PMID:18481094

  9. Does temporal variation of mercury levels in Arctic seabirds reflect changes in global environmental contamination, or a modification of Arctic marine food web functioning?

    Science.gov (United States)

    Fort, Jérôme; Grémillet, David; Traisnel, Gwendoline; Amélineau, Françoise; Bustamante, Paco

    2016-04-01

    Studying long-term trends of contaminants in Arctic biota is essential to better understand impacts of anthropogenic activities and climate change on the exposure of sensitive species and marine ecosystems. We concurrently measured temporal changes (2006-2014) in mercury (Hg) contamination of little auks (Alle alle; the most abundant Arctic seabird) and in their major zooplankton prey species (Calanoid copepods, Themisto libellula, Gammarus spp.). We found an increasing contamination of the food-chain in East Greenland during summer over the last decade. More specifically, bird contamination (determined by body feather analyses) has increased at a rate of 3.4% per year. Conversely, bird exposure to Hg during winter in the northwest Atlantic (determined by head feather analyses) decreased over the study period (at a rate of 1.5% per year), although winter concentrations remained consistently higher than during summer. By combining mercury levels measured in birds and zooplankton to isotopic analyses, our results demonstrate that inter-annual variations of Hg levels in little auks reflect changes in food-chain contamination, rather than a reorganization of the food web and a modification of seabird trophic ecology. They therefore underline the value of little auks, and Arctic seabirds in general, as bio-indicators of long-term changes in environmental contamination. PMID:26798998

  10. Does temporal variation of mercury levels in Arctic seabirds reflect changes in global environmental contamination, or a modification of Arctic marine food web functioning?

    Science.gov (United States)

    Fort, Jérôme; Grémillet, David; Traisnel, Gwendoline; Amélineau, Françoise; Bustamante, Paco

    2016-04-01

    Studying long-term trends of contaminants in Arctic biota is essential to better understand impacts of anthropogenic activities and climate change on the exposure of sensitive species and marine ecosystems. We concurrently measured temporal changes (2006-2014) in mercury (Hg) contamination of little auks (Alle alle; the most abundant Arctic seabird) and in their major zooplankton prey species (Calanoid copepods, Themisto libellula, Gammarus spp.). We found an increasing contamination of the food-chain in East Greenland during summer over the last decade. More specifically, bird contamination (determined by body feather analyses) has increased at a rate of 3.4% per year. Conversely, bird exposure to Hg during winter in the northwest Atlantic (determined by head feather analyses) decreased over the study period (at a rate of 1.5% per year), although winter concentrations remained consistently higher than during summer. By combining mercury levels measured in birds and zooplankton to isotopic analyses, our results demonstrate that inter-annual variations of Hg levels in little auks reflect changes in food-chain contamination, rather than a reorganization of the food web and a modification of seabird trophic ecology. They therefore underline the value of little auks, and Arctic seabirds in general, as bio-indicators of long-term changes in environmental contamination.

  11. Biodiversity of Arctic marine ecosystems and responses to climate change

    DEFF Research Database (Denmark)

    Michel, C.; Bluhm, B.; Gallucci, V.;

    2012-01-01

    . These changes have important impacts on the chemical and biological processes that are at the root of marine food webs, influencing their structure, function and biodiversity. Here we summarise current knowledge on the biodiversity of Arctic marine ecosystems and provide an overview of fundamental factors...... that structure ecosystem biodiversity in the Arctic Ocean. We also discuss climateassociated effects on the biodiversity of Arctic marine ecosystems and discuss implications for the functioning of Arctic marine food webs. Based on the complexity and regional character of Arctic ecosystem reponses...

  12. Seasonality in contaminant accumulation in Arctic marine pelagic food webs using trophic magnification factor as a measure of bioaccumulation.

    Science.gov (United States)

    Hallanger, Ingeborg G; Warner, Nicholas A; Ruus, Anders; Evenset, Anita; Christensen, Guttorm; Herzke, Dorte; Gabrielsen, Geir W; Borgå, Katrine

    2011-05-01

    Seasonality in biomagnification of persistent organic pollutants (POPs; polychlorinated biphenyls, chlorinated pesticides, and brominated flame retardants) in Arctic marine pelagic food webs was investigated in Kongsfjorden, Svalbard, Norway. Trophic magnification factors (TMFs; average factor change in concentration between two trophic levels) were used to measure food web biomagnification in biota in May, July, and October 2007. Pelagic zooplankton (seven species), fish (five species), and seabirds (two species) were included in the study. For most POP compounds, highest TMFs were found in July and lowest were in May. Seasonally changing TMFs were a result of seasonally changing POP concentrations and the δ¹⁵N-derived trophic positions of the species included in the food web. These seasonal differences in TMFs were independent of inclusion/exclusion of organisms based on physiology (i.e., warm- versus cold-blooded organisms) in the food web. The higher TMFs in July, when the food web consisted of a higher degree of boreal species, suggest that future warming of the Arctic and increased invasion by boreal species can result in increased food web magnification. Knowledge of the seasonal variation in POP biomagnification is a prerequisite for understanding changes in POP biomagnification caused by climate change.

  13. Seasonality in contaminant accumulation in Arctic marine pelagic food webs using trophic magnification factor as a measure of bioaccumulation.

    Science.gov (United States)

    Hallanger, Ingeborg G; Warner, Nicholas A; Ruus, Anders; Evenset, Anita; Christensen, Guttorm; Herzke, Dorte; Gabrielsen, Geir W; Borgå, Katrine

    2011-05-01

    Seasonality in biomagnification of persistent organic pollutants (POPs; polychlorinated biphenyls, chlorinated pesticides, and brominated flame retardants) in Arctic marine pelagic food webs was investigated in Kongsfjorden, Svalbard, Norway. Trophic magnification factors (TMFs; average factor change in concentration between two trophic levels) were used to measure food web biomagnification in biota in May, July, and October 2007. Pelagic zooplankton (seven species), fish (five species), and seabirds (two species) were included in the study. For most POP compounds, highest TMFs were found in July and lowest were in May. Seasonally changing TMFs were a result of seasonally changing POP concentrations and the δ¹⁵N-derived trophic positions of the species included in the food web. These seasonal differences in TMFs were independent of inclusion/exclusion of organisms based on physiology (i.e., warm- versus cold-blooded organisms) in the food web. The higher TMFs in July, when the food web consisted of a higher degree of boreal species, suggest that future warming of the Arctic and increased invasion by boreal species can result in increased food web magnification. Knowledge of the seasonal variation in POP biomagnification is a prerequisite for understanding changes in POP biomagnification caused by climate change. PMID:21312250

  14. Examination of the bioaccumulation of halogenated dimethyl bipyrroles in an Arctic marine food web using stable nitrogen isotope analysis.

    Science.gov (United States)

    Tittlemier, Sheryl A; Fisk, Aaron T; Hobson, Keith A; Norstrom, Ross J

    2002-01-01

    Concentrations of four possibly naturally produced organohalogens--1,1'-dimethyl-3,3',4-tribromo-4,5,5'-trichloro-2,2'-bipyrrole (DBP-Br3Cl3), 1,1'-dimethyl-3,3',4,4'-tetrabromo-5,5'-dichloro-2,2'-bipyrrole (DBP-Br4Cl2), 1,1'-dimethyl-3,3',4,4',5-pentabromo-5'-chloro-2,2'-bipyrrole (DBP-Br5Cl) and 1,1'-dimethyl-3,3',4,4',5,5'-hexabromo-2,2'-bipyrrole (DBP-Br6)--were quantitated and the extent of their magnification through an entire Arctic marine food web [measured as integrated trophic magnification factors (TMFs)] were calculated. The food web consisted of three zooplankton species (Calanus hyperboreus, Mysis oculata, and Sagitta sp.), one fish species [Arctic cod (Boreogadus saida)], four seabird species [dovekie (Alle alle), black guillemot (Cepphus grylle), black-legged kittiwake (Rissa tridactyla), and glaucous gull (Larus hyperboreus)], and one marine mammal species [ringed seal (Phoca hispida)]. Trophic levels in the food web were calculated from ratios of stable isotopes of nitrogen (15N/14N). All halogenated dimethyl bipyrrole (HDBP) congeners were found to significantly (Ptrophic level in the invertebrate--fish--seabird food web. DBP-Br4Cl2 (TMF= 14.6) was found to biomagnify to a greater extent than DBP-Br3Cl3 (TMF = 5.2), DBP-Br5Cl (TMF = 6.9), or DBP-Br6 (TMF = 7.0), even though the Kow of DBP-Br4CI2 was predicted to be lower than those of DBP-Br5Cl and DBP-Br6. None of the four HDBP congeners in ringed seals followed the general trend of increasing concentration with trophic level, which was possibly due to an ability of the seals to metabolize HDBPs. PMID:11808557

  15. Spatial variability of carbon (δ13C) and nitrogen (δ15N) stable isotope ratios in an Arctic marine food web

    DEFF Research Database (Denmark)

    Hansen, Joan Holst; Hedeholm, Rasmus Berg; Sünksen, Kaj;

    2012-01-01

    Stable isotopes of carbon (δ13C) and nitrogen (δ15N) were used to examine trophic structures in an arctic marine food web at small and large spatial scales. Twelve species, from primary consumers to Greenland shark, were sampled at a large spatial scale near the west and east coasts of Greenland...

  16. Chytrids dominate arctic marine fungal communities.

    Science.gov (United States)

    Hassett, B T; Gradinger, R

    2016-06-01

    Climate change is altering Arctic ecosystem structure by changing weather patterns and reducing sea ice coverage. These changes are increasing light penetration into the Arctic Ocean that are forecasted to increase primary production; however, increased light can also induce photoinhibition and cause physiological stress in algae and phytoplankton that can favour disease development. Fungi are voracious parasites in many ecosystems that can modulate the flow of carbon through food webs, yet are poorly characterized in the marine environment. We provide the first data from any marine ecosystem in which fungi in the Chytridiomycota dominate fungal communities and are linked in their occurrence to light intensities and algal stress. Increased light penetration stresses ice algae and elevates disease incidence under reduced snow cover. Our results show that chytrids dominate Arctic marine fungal communities and have the potential to rapidly change primary production patterns with increased light penetration. PMID:26754171

  17. Contamination of an arctic terrestrial food web with marine-derived persistent organic pollutants transported by breeding seabirds

    Energy Technology Data Exchange (ETDEWEB)

    Choy, Emily S., E-mail: echoy087@uottawa.c [Program for Chemical and Environmental Toxicology, Department of Biology, University of Ottawa, Ottawa, ON, K1N 6N5 (Canada); Kimpe, Linda E., E-mail: linda.kimpe@uottawa.c [Program for Chemical and Environmental Toxicology, Department of Biology, University of Ottawa, Ottawa, ON, K1N 6N5 (Canada); Mallory, Mark L., E-mail: mark.mallory@ec.gc.c [Canadian Wildlife Service, Environment Canada, Iqaluit, NU, X0A 0H0 (Canada); Smol, John P., E-mail: smolj@queensu.c [Paleoecological Environmental Assessment and Research Lab (PEARL), Department of Biology, Queen' s University, Kingston, ON, K7L 3N6 (Canada); Blais, Jules M., E-mail: jules.blais@uottawa.c [Program for Chemical and Environmental Toxicology, Department of Biology, University of Ottawa, Ottawa, ON, K1N 6N5 (Canada)

    2010-11-15

    At Cape Vera, Devon Island (Nunavut, Canada), a colony of northern fulmars (Fulmarus glacialis) concentrates and releases contaminants through their guano to the environment. We determined whether persistent organic pollutants (POPs) from seabirds were transferred to coastal food webs. Snow buntings (Plectrophenax nivalis) were the most contaminated species, with {Sigma}PCB and {Sigma}DDT (mean: 168, 106 ng/g ww) concentrations surpassing environmental guidelines for protecting wildlife. When examined collectively, PCB congeners and DDT in jewel lichen (Xanthoria elegans) were lower in samples taken farther from the seabird colony, and increased with increasing {delta}{sup 15}N values. However, only concentrations of p'p-DDE:{Sigma}DDT and PCB-95 were significantly correlated inversely with distance from the seabird cliffs. Linkages between marine-derived POPs and their concentrations in terrestrial mammals were less clear. Our study provides novel contaminant data for these species and supports biovector transport as a source of organic contaminants to certain components of the terrestrial food web. - This study provides evidence of contaminant transport by seabirds to a coastal Arctic food web.

  18. Contamination of an arctic terrestrial food web with marine-derived persistent organic pollutants transported by breeding seabirds

    International Nuclear Information System (INIS)

    At Cape Vera, Devon Island (Nunavut, Canada), a colony of northern fulmars (Fulmarus glacialis) concentrates and releases contaminants through their guano to the environment. We determined whether persistent organic pollutants (POPs) from seabirds were transferred to coastal food webs. Snow buntings (Plectrophenax nivalis) were the most contaminated species, with ΣPCB and ΣDDT (mean: 168, 106 ng/g ww) concentrations surpassing environmental guidelines for protecting wildlife. When examined collectively, PCB congeners and DDT in jewel lichen (Xanthoria elegans) were lower in samples taken farther from the seabird colony, and increased with increasing δ15N values. However, only concentrations of p'p-DDE:ΣDDT and PCB-95 were significantly correlated inversely with distance from the seabird cliffs. Linkages between marine-derived POPs and their concentrations in terrestrial mammals were less clear. Our study provides novel contaminant data for these species and supports biovector transport as a source of organic contaminants to certain components of the terrestrial food web. - This study provides evidence of contaminant transport by seabirds to a coastal Arctic food web.

  19. Biomagnification of mercury in selected species from an Arctic marine food web in Svalbard

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, Iris, E-mail: iris@akvaplan.niva.no [Norwegian Polar Institute, N-9296 Tromso (Norway); University of Tromso, Institute of Biology, N-9037 Tromso (Norway); Hop, Haakon; Gabrielsen, Geir W. [Norwegian Polar Institute, N-9296 Tromso (Norway)

    2009-08-01

    Concentrations and biomagnification of total mercury (TotHg) and methyl mercury (MeHg) were studied in selected species from the pelagic food web in Kongsfjorden, Svalbard. Twelve species of zooplankton, fish and seabirds, were sampled representing a gradient of trophic positions in the Svalbard marine food web. TotHg and MeHg were analysed in liver, muscle and/or whole specimens. The present study is the first to provide MeHg levels in seabirds from the Svalbard area. The relative MeHg levels decreased with increasing levels of TotHg in seabird tissues. Stable isotopes of nitrogen ({delta}{sup 15}N) were used to determine the trophic levels and the rate of biomagnification of mercury in the food web. A linear relationship between mercury levels and trophic position was found for all seabird species combined and their trophic level, but there was no relationship within species. Biomagnification factors were all > 1 for both TotHg and MeHg, indicating biomagnification from prey to predator. TotHg levels in the different seabirds were similar to levels detected in the Kongsfjorden area in the 1990s.

  20. Biomagnification of mercury in selected species from an Arctic marine food web in Svalbard.

    Science.gov (United States)

    Jaeger, Iris; Hop, Haakon; Gabrielsen, Geir W

    2009-08-01

    Concentrations and biomagnification of total mercury (TotHg) and methyl mercury (MeHg) were studied in selected species from the pelagic food web in Kongsfjorden, Svalbard. Twelve species of zooplankton, fish and seabirds, were sampled representing a gradient of trophic positions in the Svalbard marine food web. TotHg and MeHg were analysed in liver, muscle and/or whole specimens. The present study is the first to provide MeHg levels in seabirds from the Svalbard area. The relative MeHg levels decreased with increasing levels of TotHg in seabird tissues. Stable isotopes of nitrogen (delta(15)N) were used to determine the trophic levels and the rate of biomagnification of mercury in the food web. A linear relationship between mercury levels and trophic position was found for all seabird species combined and their trophic level, but there was no relationship within species. Biomagnification factors were all >1 for both TotHg and MeHg, indicating biomagnification from prey to predator. TotHg levels in the different seabirds were similar to levels detected in the Kongsfjorden area in the 1990s. PMID:19454364

  1. Environmental marine geology of the Arctic Ocean

    International Nuclear Information System (INIS)

    The Arctic Ocean and its ice cover are major regulators of Northern Hemisphere climate, ocean circulation and marine productivity. The Arctic is also very sensitive to changes in the global environment because sea ice magnifies small changes in temperature, and because polar regions are sinks for air pollutants. Marine geology studies are being carried out to determine the nature and rate of these environmental changes by study of modern ice and sea bed environments, and by interpretation of geological records imprinted in the sea floor sediments. Sea ice camps, an ice island, and polar icebreakers have been used to study both western and eastern Arctic Ocean basins. Possible early warning signals of environmental changes in the Canadian Arctic are die-back in Arctic sponge reefs, outbreaks of toxic dinoflagellates, and pesticides in the marine food chain. Eastern Arctic ice and surface waters are contaminated by freon and radioactive fallout from Chernobyl. At present, different sedimentary processes operate in the pack ice-covered Canadian polar margin than in summer open waters off Alaska and Eurasia. The geological records, however, suggest that a temperature increase of 1-4C would result in summer open water throughout the Arctic, with major changes in ocean circulation and productivity of waters off Eastern North America, and more widespread transport of pollutants from eastern to western Arctic basins. More studies of longer sediment cores are needed to confirm these interpretations, but it is now clear that the Arctic Ocean has been the pacemaker of climate change during the past 1 million years

  2. Environmental marine geology of the Arctic Ocean

    International Nuclear Information System (INIS)

    The Arctic Ocean and its ice cover are major regulators of Northern Hemisphere climate, ocean circulation and marine productivity. The Arctic is also very sensitive to changes in the global environment because sea ice magnifies small changes in temperature, and because polar regions are sinks for air pollutants. Marine geology studies are being carried out to determine the nature and rate of these environmental changes by study of modem ice and sea-bed environments, and by interpretation of geological records imprinted in the sea-floor sediments. Sea ice camps, an ice island, and polar icebreakers have been used to study both western and eastern Arctic Ocean basins. Possible early warning signals of environmental changes in the Canadian Arctic are die-back in Arctic sponge reefs, outbreaks of toxic dinoflagellates, and pesticides in the marine food chain. Eastern Arctic ice and surface waters are contaminated by freon and radioactive fallout from Chernobyl. At present, different sedimentary processes operate in the pack ice-covered Canadian polar margin than in summer open waters off Alaska and Eurasia. The geological records, however, suggest that a temperature increase of 1-4 degree C would result in summer open water throughout the Arctic, with major changes in ocean circulation and productivity of waters off Eastern North America, and more widespread transport of pollutants from eastern to western Arctic basins. More studies of longer sediment cores are needed to confirm these interpretations, but is is now clear that the Arctic Ocean has been the pacemaker of climate change during the past 1 million years

  3. Basal mercury concentrations and biomagnification rates in freshwater and marine food webs: Effects on Arctic charr (Salvelinus alpinus) from eastern Canada

    Energy Technology Data Exchange (ETDEWEB)

    Velden, S. van der, E-mail: sdorn@uwaterloo.ca [Department of Biology, University of Waterloo, Waterloo, Ontario, Canada, N2L 3G1 (Canada); Dempson, J.B. [Fisheries and Oceans Canada, St. John' s, Newfoundland and Labrador, Canada, A1C 5X1 (Canada); Evans, M.S. [Environment Canada, Saskatoon, Saskatchewan, Canada, S7N 3H5 (Canada); Muir, D.C.G. [Environment Canada, Burlington, Ontario, Canada, L7R 4A6 (Canada); Power, M., E-mail: m3power@uwaterloo.ca [Department of Biology, University of Waterloo, Waterloo, Ontario, Canada, N2L 3G1 (Canada)

    2013-02-01

    Patterns of total Hg (THg) and methyl Hg (MeHg) biomagnification were investigated in six pairs of co-located lacustrine and marine food webs supporting a common predator, Arctic charr. Mercury biomagnification rates (the slope of log Hg concentration versus δ{sup 15}N-inferred trophic level) did not differ significantly between the two feeding habitats for either THg or MeHg, but THg and MeHg concentrations at the base of the food web were higher in the lacustrine environment than in the marine environment. The proportion of THg as MeHg was related to trophic level, and the relationship was statistically similar in the lacustrine and marine habitats. The biomagnification rate of MeHg exceeded that of THg in both habitats. We conclude that the known difference in Hg concentration between anadromous and non-anadromous Arctic charr is driven by differential Hg concentrations at the base of the lacustrine and marine foodwebs, and not by differential biomagnification rates. - Highlights: ► Concentrations of total mercury ([THg]) and methylmercury ([MeHg]) were measured in 6 paired lacustrine and marine food webs. ► Biomagnification rates (slopes of [THg] or [MeHg] versus δ{sup 15}N-inferred trophic level) were similar in the two habitat types. ► Mercury concentrations at the base of the food web were higher in lacustrine than in marine food webs. ► The percentage of methylated mercury increased with trophic level similarly in the two habitat types. ► The biomagnification rate of MeHg exceeded that of THg in both habitats.

  4. Basal mercury concentrations and biomagnification rates in freshwater and marine food webs: Effects on Arctic charr (Salvelinus alpinus) from eastern Canada

    International Nuclear Information System (INIS)

    Patterns of total Hg (THg) and methyl Hg (MeHg) biomagnification were investigated in six pairs of co-located lacustrine and marine food webs supporting a common predator, Arctic charr. Mercury biomagnification rates (the slope of log Hg concentration versus δ15N-inferred trophic level) did not differ significantly between the two feeding habitats for either THg or MeHg, but THg and MeHg concentrations at the base of the food web were higher in the lacustrine environment than in the marine environment. The proportion of THg as MeHg was related to trophic level, and the relationship was statistically similar in the lacustrine and marine habitats. The biomagnification rate of MeHg exceeded that of THg in both habitats. We conclude that the known difference in Hg concentration between anadromous and non-anadromous Arctic charr is driven by differential Hg concentrations at the base of the lacustrine and marine foodwebs, and not by differential biomagnification rates. - Highlights: ► Concentrations of total mercury ([THg]) and methylmercury ([MeHg]) were measured in 6 paired lacustrine and marine food webs. ► Biomagnification rates (slopes of [THg] or [MeHg] versus δ15N-inferred trophic level) were similar in the two habitat types. ► Mercury concentrations at the base of the food web were higher in lacustrine than in marine food webs. ► The percentage of methylated mercury increased with trophic level similarly in the two habitat types. The biomagnification rate of MeHg exceeded that of THg in both habitats

  5. Dangerous relations in the Arctic marine food web: Interactions between toxin producing Pseudo-nitzschia diatoms and Calanus copepodites

    DEFF Research Database (Denmark)

    Hardardottir, Sara; Pancic, Marina; Tammilehto, Anna;

    2015-01-01

    Diatoms of the genus Pseudo-nitzschia produce domoic acid (DA), a toxin that is vectored in the marine food web, thus causing serious problems for marine organisms and humans. In spite of this, knowledge of interactions between grazing zooplankton and diatoms is restricted. In this study, we exam...

  6. Temporal and spatial variation in polychlorinated biphenyl chiral signatures of the Greenland shark (Somniosus microcephalus) and its arctic marine food web

    International Nuclear Information System (INIS)

    Polychlorinated biphenyls (PCBs) chiral signatures were measured in Greenland sharks (Somniosus microcephalus) and their potential prey in arctic marine food webs from Canada (Cumberland Sound) and Europe (Svalbard) to assess temporal and spatial variation in PCB contamination at the stereoisomer level. Marine mammals had species-specific enantiomer fractions (EFs), likely due to a combination of in vivo biotransformation and direct trophic transfer. Greenland sharks from Cumberland Sound in 2007–2008 had similar EFs to those sharks collected a decade ago in the same location (PCBs 91, 136 and 149) and also similar to their conspecifics from Svalbard for some PCB congeners (PCBs 95, 136 and 149). However, other PCB EFs in the sharks varied temporally (PCB 91) or spatially (PCB 95), suggesting a possible spatiotemporal variation in their diets, since biotransformation capacity was unlikely to have varied within this species from region to region or over the time frame studied. -- Highlights: • Chiral PCB signatures were measured in Greenland sharks and their prey. • Marine mammals accumulated non-racemic PCBs from biotransformation and their diet. • Chiral PCB signatures were similar in sharks at two different arctic locations. • Some changes in chiral PCB signatures in sharks over a decade. -- PCB chiral signatures in Greenland sharks shift over time and space, likely in parallel with dietary variation

  7. Dining Dovekies Demand, "When, Where and What's for Dinner?" The Impact of Seasonal Changes in Snow Melt and the Development of the Arctic Marine Food Web on Seabirds.

    Science.gov (United States)

    Karnovsky, N. J.; Harding, A.; Welcker, J.; Brown, Z. W.; Kitaysky, A.; Kwasniewski, S.; Walkusz, W.; Gremillet, D.

    2011-12-01

    The Atlantic sector of the Arctic is undergoing widespread climate change with increases in air and sea temperatures which impact the timing of ice retreat, snow melt and the development of the marine food web. Dovekies (Alle alle) are small seabirds that migrate to the Atlantic Sector of the Arctic to feed in ice free waters that have abundant lipid-rich zooplankton. In the Greenland Sea, the dovekies are largely dependent on the advection of Calanus copepods into the area. We hypothesized that dovekies breeding adjacent to water masses which bring smaller, less energy-rich prey into the region (Calanus finmarchicus), work harder to find food and have higher stress levels. We tested this hypothesis by attaching time-depth recorders to provisioning dovekies at three colonies adjacent to different water masses (the West Spistbergen Current, the East Greenland Current, and the Sorkapp Current). We determined the length of time dovekies at different colonies spent at-sea collecting food for themselves and their chicks. We measured circulating corticosteroid hormone levels in their blood to assess stress levels. We collected chick meals to determine the energetic content of prey fed chicks at the different colonies. We found that dovekies are sensitive to the quality of prey available to them. Dovekies exposed to less profitable prey made longer foraging trips and worked harder while at-sea to collect prey for themselves and their chicks. Furthermore, over the past 50 years, dovekies breeding along the western shores of Spitsbergen have initiated breeding earlier in spring as their nest sites have become snow-free at earlier dates. We evaluate the impact of earlier breeding and the timing of the development of the marine food web within different currents which advect and/or support Calanus copepods into the Greenland Sea. Future possible declines in dovekies may impact terrestrial food webs which are highly influenced by the annual input of nitrogen rich guano on the

  8. Dangerous relations in the Arctic marine food web: Interactions between toxin producing Pseudo-nitzschia diatoms and Calanus copepodites

    DEFF Research Database (Denmark)

    Hardardottir, Sara; Pancic, Marina; Tammilehto, Anna;

    2015-01-01

    Diatoms of the genus Pseudo-nitzschia produce domoic acid (DA), a toxin that is vectored in the marine food web, thus causing serious problems for marine organisms and humans. In spite of this, knowledge of interactions between grazing zooplankton and diatoms is restricted. In this study, we...... examined the interactions between Calanus copepodites and toxin producing Pseudo-nitzschia. The copepodites were fed with different concentrations of toxic P. seriata and a strain of P. obtusa that previously was tested to be non-toxic. The ingestion rates did not differ among the diets (P. seriata, P...

  9. Marine Transportation Implications of the Last Arctic Sea Ice Refuge

    Science.gov (United States)

    Brigham, L. W.

    2010-12-01

    Marine access is increasing throughout the Arctic Ocean and the 'Last Arctic Sea Ice Refuge' may have implications for governance and marine use in the region. Arctic marine transportation is increasing due to natural resource developemnt, increasing Arctic marine tourism, expanded Arctic marine research, and a general linkage of the Arctic to the gloabl economy. The Arctic Council recognized these changes with the release of the Arctic Marine Shipping Assessment of 2009. This key study (AMSA)can be viewed as a baseline assessment (using the 2004 AMSA database), a strategic guide for a host of stakeholders and actors, and as a policy document of the Arctic Council. The outcomes of AMSA of direct relevance to the Ice Refuge are within AMSA's 17 recommendations provided under three themes: Enhancing Arctic Marine Safety, Protecting Arctic People and the Environment, and Building the Arctic Marine Infrastructure. Selected recommendations of importance to the Ice Refuge include: a mandatory polar navigation code; identifying areas of heightened ecological and cultural significance; potential designation of special Arctic marine areas; enhancing the tracking and monitoring of Arctic marine traffic; improving circumpolar environmental response capacity; developing an Arctic search and rescue agreement; and, assessing the effects of marine transportation on marine mammals. A review will be made of the AMSA outcomes and how they can influence the governance, marine use, and future protection of this unique Arctic marine environment.

  10. Land-Based Marine Pollution in Arctic

    OpenAIRE

    Haile, Fitsum Gebreselassie

    2014-01-01

    Land-based pollution represents the single most important cause of marine pollution. The threat of land-based pollution to the marine environment is a serious one since it mainly affects coastal waters, which are sites of high biological productivity. The occurrence of high concentrations of pollutants in the Arctic environment has been a concern for many years.. Regional and international actions over the past two decades attempting to manage pollutants in the Arctic environment from land- b...

  11. Enantioselective bioaccumulation of hexabromocyclododecane and congener-specific accumulation of brominated diphenyl ethers in an eastern Canadian Arctic marine food web.

    Science.gov (United States)

    Tomy, Gregg T; Pleskach, Kerri; Oswald, Tyler; Halldorson, Thor; Helm, Paul A; MacInnis, Gordia; Marvin, Chris H

    2008-05-15

    The extent of trophic transfer of the three diastereoisomers of hexabromocyclododecane (HBCD) and seven brominated diphenyl ether (BDE) congeners was examined in components of an Arctic marine food web from eastern Canada. Alpha and gamma-HBCD diastereoisomers were detected in all species and total (sigma) HBCD concentrations ranged from 0.6 +/- 0.2 pg/g (geometric mean +/- 1 x standard error (SE), lipid weight (lw)) in arctic cod to 3.9 +/- 0.9 ng/g (lw) in narwhal. beta-HBCD was below method detection limits in all the samples. Mean sigmaBDE (sum of seven congeners) concentrations ranged from 0.4 +/- 0.2 ng/g (lw) in walrus to 73 +/- 10 ng/g (lw) in zooplankton. The relative trophic status of biota was determined by nitrogen stable isotopes (delta15N), and results indicated clear differences in HBCD isomer and BDE congener profiles with trophic level (TL). Trophic magnification was observed for the alpha-diastereoisomer and BDE-47 as concentrations increased with increasing TL in the food web, whereas there was trophic dilution of gamma-HBCD and BDE-209 through the food web. Only the (-)alpha-enantiomer showed a strong positive relationship between concentration and TL (p trophic magnification factor (TMF) value of 2.2. A small but significant increase in the enantiomeric fraction value of the alpha-enantiomers with TL was also observed (r2 = 0.22, p < 0.005), implying that there is an overall preferential enrichment of the (-)alpha-enantiomer relative to the (+)alpha-enantiomer likely due to the greater bioaccumulation potential of the (-)alpha-enantiomer and/or to the greater susceptibility of the (+)alpha-enantiomer to metabolism. PMID:18546701

  12. Dangerous Relations in the Arctic Marine Food Web: Interactions between Toxin Producing Pseudo-nitzschia Diatoms and Calanus Copepodites

    Directory of Open Access Journals (Sweden)

    Sara Harðardóttir

    2015-06-01

    Full Text Available Diatoms of the genus Pseudo-nitzschia produce domoic acid (DA, a toxin that is vectored in the marine food web, thus causing serious problems for marine organisms and humans. In spite of this, knowledge of interactions between grazing zooplankton and diatoms is restricted. In this study, we examined the interactions between Calanus copepodites and toxin producing Pseudo-nitzschia. The copepodites were fed with different concentrations of toxic P. seriata and a strain of P. obtusa that previously was tested to be non-toxic. The ingestion rates did not differ among the diets (P. seriata, P. obtusa, a mixture of both species, and they accumulated 6%–16% of ingested DA (up to 420 µg per dry weight copepodite. When P. seriata was exposed to the copepodites, either through physical contact with the grazers or separated by a membrane, the toxicity of P. seriata increased (up to 3300% suggesting the response to be chemically mediated. The induced response was also triggered when copepodites grazed on another diatom, supporting the hypothesis that the cues originate from the copepodite. Neither pH nor nutrient concentrations explained the induced DA production. Unexpectedly, P. obtusa also produced DA when exposed to grazing copepodites, thus representing the second reported toxic polar diatom.

  13. Marine functional food

    NARCIS (Netherlands)

    Luten, J.B.

    2009-01-01

    This book reviews the research on seafood and health, the use and quality aspects of marine lipids and seafood proteins as ingredients in functional foods and consumer acceptance of (marine) functional food. The first chapter covers novel merging areas where seafood may prevent disease and improve h

  14. Evolution of the Arctic Calanus complex: an Arctic marine avocado?

    OpenAIRE

    Berge, Jørgen; Gabrielsen, Tove M.; Mark A Moline; Renaud, Paul

    2012-01-01

    Before man hunted the large baleen whales to near extinction by the end of the nineteenth century, Arctic ecosystems were strongly influenced by these large predators. Their main prey were zooplankton, among which the calanoid copepod species of the genus Calanus, long considered key elements of polar marine ecosystems, are particularly abundant. These herbivorous zooplankters display a range of adaptations to the highly seasonal environments of the polar oceans, most notably extensive energy...

  15. Alaska Arctic marine fish ecology catalog

    Science.gov (United States)

    Thorsteinson, Lyman K.; Love, Milton S.

    2016-08-08

    The marine fishes in waters of the United States north of the Bering Strait have received new and increased scientific attention over the past decade (2005–15) in conjunction with frontier qualities of the region and societal concerns about the effects of Arctic climate change. Commercial fisheries are negligible in the Chukchi and Beaufort Seas, but many marine species have important traditional and cultural values to Alaska Native residents. Although baseline conditions are rapidly changing, effective decisions about research and monitoring investments must be based on reliable information and plausible future scenarios. For the first time, this synthesis presents a comprehensive evaluation of the marine fish fauna from both seas in a single reference. Although many unknowns and uncertainties remain in the scientific understanding, information presented here is foundational with respect to understanding marine ecosystems and addressing dual missions of the U.S. Department of the Interior for energy development and resource conservation. 

  16. Alaska Arctic marine fish ecology catalog

    Science.gov (United States)

    2016-01-01

    The marine fishes in waters of the United States north of the Bering Strait have received new and increased scientific attention over the past decade (2005–15) in conjunction with frontier qualities of the region and societal concerns about the effects of Arctic climate change. Commercial fisheries are negligible in the Chukchi and Beaufort Seas, but many marine species have important traditional and cultural values to Alaska Native residents. Although baseline conditions are rapidly changing, effective decisions about research and monitoring investments must be based on reliable information and plausible future scenarios. For the first time, this synthesis presents a comprehensive evaluation of the marine fish fauna from both seas in a single reference. Although many unknowns and uncertainties remain in the scientific understanding, information presented here is foundational with respect to understanding marine ecosystems and addressing dual missions of the U.S. Department of the Interior for energy development and resource conservation. 

  17. The delivery of organic contaminants to the Arctic food web: Why sea ice matters

    DEFF Research Database (Denmark)

    Pucko, M.; Stern, Gary; Macdonald, Robie;

    2015-01-01

    For decades sea ice has been perceived as a physical barrier for the loading of contaminants to the Arctic Ocean. We show that sea ice, in fact, facilitates the delivery of organic contaminants to the Arctic marine food web through processes that: 1) are independent of contaminant physical–chemic...

  18. Large ancient organic matter contributions to Arctic marine sediments (Svalbard)

    NARCIS (Netherlands)

    Kim, J.-H.; Peterse, F.; Willmott, V.; Klitgaard Kristensen, D.; Baas, M.; Schouten, S.; Sinninghe Damsté, J.S.

    2011-01-01

    Soils, fine-grained ice-rafted detritus (IRD), coals, and marine surface sediments in the Arctic realm (Svalbard) were collected in 2007 and 2008 to characterize organic matter (OM) sources in Arctic marine sediments. Bulk geochemical (C : N ratio and stable carbon isotopic composition) parameters s

  19. Large ancient organic matter contributions to Arctic marine sediments (Svalbard)

    NARCIS (Netherlands)

    Kim, J.-H.; Peterse, F.; Willmott, V.; Klitgaard Kristensen, D.; Baas, M.; Schouten, S.; Sinninghe Damsté, J.S.

    2011-01-01

    Soils, fine-grained ice-rafted detritus (IRD), coals, and marine surface sediments in the Arctic realm (Svalbard)were collected in 2007 and 2008 to characterize organic matter (OM) sources in Arctic marine sediments. Bulkgeochemical (C : N ratio and stable carbon isotopic composition) parameters sug

  20. Adapting Governance and Regulation of the Marine Arctic

    NARCIS (Netherlands)

    Molenaar, Erik

    2014-01-01

    The Arctic is currently undergoing change at a pace many would not have considered possible just a decade or so ago. It is therefore reasonable to argue that while the international law and policy regime for the governance and regulation of the marine Arctic may have been adequate for an ice-dominat

  1. Towards Arctic Resource Governance of Marine Invasive Species

    DEFF Research Database (Denmark)

    Kourantidou, Melina; Kaiser, Brooks; Fernandez, Linda

    2015-01-01

    Scientific and policy-oriented publications highlighting the magnitude of uncertainty in the changing Arctic and the possibilities for effective regional governance are proliferating, yet it remains a challenging task to examine Arctic marine biodiversity. Limited scientific data are currently av...

  2. Legal Instruments for Marine Sanctuary in the High Arctic

    Directory of Open Access Journals (Sweden)

    Kathleen Morris

    2016-05-01

    Full Text Available In response to heightened threat to Arctic marine biodiversity due to polar ice melt, the following paper seeks to use qualitative secondary research to analyze existing anthropogenic threat to Arctic marine life and to evaluate current efforts on the part of the Arctic Council to protect biodiversity through a network of state-created marine protected areas (MPAs. We conclude that the current method for MPA creation fails to offer adequate pathways for creation of MPAs in Areas Beyond National Jurisdiction (ABNJ, the high seas which fall beyond individual countries’ exclusive economic zones (EEZs. Thus, our central research question is to determine what legal basis and mechanisms exist for the creation of MPAs in ABNJs, with particular focus on the Arctic marine environment. In keeping with The United Nations Convention on Biological Diversity’s (UNCBD precautionary approach, along with specific rules embodied within The United Nations Convention on the Law of the Sea (UNCLOS, we find a basis for creation of MPAs in the ABNJ. The text evaluates findings from the Boulogne-sur-Mer international conference of 2011 to suggest that such MPA creation in ABNJ could be approached via four pathways: regional agreement, UNCLOS implementing agreement, UNCBD additional protocol, or an Arctic Sanctuary modeled on the Antarctic Treaty. While we explore all four options, we argue that, due to geopolitical constraints, a comprehensive regional agreement offers the best path to High Arctic MPA creation.

  3. Marine Arctic science capability making big strides

    Science.gov (United States)

    Johnson, Leonard; Brass, Garrett

    The profound influence of the Arctic Ocean on global environment, the rapid variability of Arctic processes, and the unresolved geology of the ocean floor have led to growing scientific interest in this region. Ongoing studies are investigating recent historical processes and modern processes such as changes in ocean circulation and ice cover patterns. Sediments beneath the Arctic Ocean record long- and short-term waxing and waning of the cryosphere in the Northern Hemisphere and its linkages to bottom water renewal and faunal adaptation. Underlying basement rocks reflect the tectonic history of the ocean basin, including its ridges and plateaus, which are unsampled and of unknown composition and origin. The vulnerability of Arctic populations to environmental problems makes the need to understand the region even more compelling (see, for example, Arctic Monitoring and Assessment Programme, 1997; also see Web site http://www.grida.no/amap).

  4. Arctic Marine Transportation Program 1979-1986

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this program was to collect data relevant to developing year-round transportation capabilities in the Arctic Ocean. The US Maritime Administration...

  5. Marine Functional Foods and Functional Ingredients

    OpenAIRE

    Hurst, D.

    2006-01-01

    This briefing paper gives insights into the issues surrounding marine functional foods and highlights opportunities for researchers in the marine sciences and food sciences areas to engage in collaborative research. It will be used as the basis for further consultation with the research community and firms in the marine and food sectors and to assist in exploring and prioritising research themes.

  6. Methylmercury biomagnification in an Arctic pelagic food web.

    Science.gov (United States)

    Ruus, Anders; Øverjordet, Ida B; Braaten, Hans Fredrik V; Evenset, Anita; Christensen, Guttorm; Heimstad, Eldbjørg S; Gabrielsen, Geir W; Borgå, Katrine

    2015-11-01

    Mercury (Hg) is a toxic element that enters the biosphere from natural and anthropogenic sources, and emitted gaseous Hg enters the Arctic from lower latitudes by long-range transport. In aquatic systems, anoxic conditions favor the bacterial transformation of inorganic Hg to methylmercury (MeHg), which has a greater potential for bioaccumulation than inorganic Hg and is the most toxic form of Hg. The main objective of the present study was to quantify the biomagnification of MeHg in a marine pelagic food web, comprising species of zooplankton, fish, and seabirds, from the Kongsfjorden system (Svalbard, Norway), by use of trophic magnification factors. As expected, tissue concentrations of MeHg increased with increasing trophic level in the food web, though at greater rates than observed in several earlier studies, especially at lower latitudes. There was strong correlation between MeHg and total Hg concentrations through the food web as a whole. The concentration of MeHg in kittiwake decreased from May to October, contributing to seasonal differences in trophic magnification factors. The ecology and physiology of the species comprising the food web in question may have a large influence on the magnitude of the biomagnification. A significant linear relationship was also observed between concentrations of selenium and total Hg in birds but not in zooplankton, suggesting the importance of selenium in Hg detoxification for individuals with high Hg concentrations. PMID:26274519

  7. Chemical pollution in the Arctic and Sub-Arctic marine ecosystems: an overview of current knowledge

    Energy Technology Data Exchange (ETDEWEB)

    Savinova, T.N.; Gabrielsen, G.W.; Falk-Petersen, S.

    1995-02-01

    This report is part of a research project in the framework of the Norwegian-Russian Environmental Cooperation, which was initiated in 1991 to elucidate the present status of environmental contaminants in the highly sensitive Arctic aquatic ecosystem, with special focus on sea birds. Although these ecosystems are the least polluted areas in the world, they are contaminated. The main pathways of contamination into Arctic and sub-Arctic marine ecosystems are atmospheric transport, ocean currents and rivers and in some areas, dumping and ship accidents. A literature survey reveals: (1) there is a lack of data from several trophic levels, (2) previous data are difficult to compare with recent data because of increased quality requirement, (3) not much has been done to investigate the effects of contaminants on the cellular level, at individual or population levels. 389 refs., 7 figs., 32 tabs.

  8. Diversity and novelty of actinobacteria in Arctic marine sediments.

    Science.gov (United States)

    Zhang, Gaiyun; Cao, Tingfeng; Ying, Jianxi; Yang, Yanliu; Ma, Lingqi

    2014-04-01

    The actinobacterial diversity of Arctic marine sediments was investigated using culture-dependent and culture-independent approaches. A total of 152 strains were isolated from seven different media; 18 isolates were selected for phylogenetic analysis on the basis of their 16S rRNA gene sequences. Results showed that the 18 isolates belonged to a potential novel genus and 10 known genera including Actinotalea, Arthrobacter, Brachybacterium, Brevibacterium, Kocuria, Kytococcus, Microbacterium, Micrococcus, Mycobacterium, and Pseudonocardia. Subsequently, 172 rDNA clones were selected by restriction fragment length polymorphism analysis from 692 positive clones within four actinobacteria-specific 16S rDNA libraries of Arctic marine sediments, and then these 172 clones were sequenced. In total, 67 phylotypes were clustered in 11 known genera of actinobacteria including Agrococcus, Cellulomonas, Demequina, Iamia, Ilumatobacter, Janibacter, Kocuria, Microbacterium, Phycicoccus, Propionibacterium, and Pseudonocardia, along with other, unidentified actinobacterial clones. Based on the detection of a substantial number of uncultured phylotypes showing low BLAST identities (<95 %), this study confirms that Arctic marine environments harbour highly diverse actinobacterial communities, many of which appear to be novel, uncultured species. PMID:24519808

  9. FRAM - FRontiers in Arctic marine Monitoring: Permanent Observations in a Gateway to the Arctic Ocean

    Science.gov (United States)

    Soltwedel, Thomas

    2015-04-01

    Our ability to understand the complex interactions of biological, chemical, physical, and geological processes in the ocean is still limited by the lack of integrative and interdisciplinary observation infrastructures. The main purpose of the open-ocean infrastructure FRAM (FRontiers in Arctic marine Monitoring) is permanent presence at sea, from surface to depth, for the provision of near real-time data on climate variability and ecosystem change in an Arctic marine environment. The Alfred-Wegener-Institut I Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), together with partner institutes in Germany and Europe, aims at providing such infrastructure for the polar ocean as a major contribution to international efforts towards comprehensive Global Earth Observation. The FRAM Ocean Observing System targets the gateway between the North Atlantic and the Central Arctic, representing a highly climate-sensitive and rapidly changing region of the Earth system. It will serve national and international tasks towards a better understanding of the effects of change in ocean circulation, water mass properties and sea-ice retreat on Arctic marine ecosystems and their main functions and services. FRAM integrates and develops already existing observatories, i.e. the oceanographic mooring array HAFOS (Hybrid Arctic/Antarctic Float Observing System) and the Long-Term Ecological Research (LTER) site HAUSGARTEN. It will implement existing and next-generation sensors and observatory platforms, allowing synchronous observation of relevant ocean variables, as well as the study of physical, chemical and biological processes in the water column and at the seafloor. Experimental and event-triggered platforms will complement observational platforms. Products of the infrastructure are continuous long-term data with appropriate resolution in space and time, as well as ground-truthing information for ocean models and remote sensing.

  10. Parasites in marine food webs

    Science.gov (United States)

    Lafferty, Kevin D.

    2013-01-01

    Most species interactions probably involve parasites. This review considers the extent to which marine ecologists should consider parasites to fully understand marine communities. Parasites are influential parts of food webs in estuaries, temperate reefs, and coral reefs, but their ecological importance is seldom recognized. Though difficult to observe, parasites can have substantial biomass, and they can be just as common as free-living consumers after controlling for body mass and trophic level. Parasites have direct impacts on the energetics of their hosts and some affect host behaviors, with ecosystem-level consequences. Although they cause disease, parasites are sensitive components of ecosystems. In particular, they suffer secondary extinctions due to biodiversity loss. Some parasites can also return to a system after habitat restoration. For these reasons, parasites can make good indicators of ecosystem integrity. Fishing can indirectly increase or decrease parasite populations and the effects of climate change on parasites are likely to be equally as complex.

  11. AMOP (Arctic Marine Oil Spill Program) studies reviewed

    Energy Technology Data Exchange (ETDEWEB)

    1978-06-05

    A discussion of the Arctic Marine Oil Spill Program organized in 1976 by the Canadian Federal Government includes: an Arctic Atlas compiled by Fenco Consultants Ltd. to give background information necessary for developing marine oil spill countermeasures for the Arctic north of 60/sup 0/ including the west Greenland coast and the Labrador shelf (geology, meteorology and oceanography, ice conditions, biology, and social factors); program in emergency transport of spill-combatting equipment; and the factors which influence the choice of conveyance, i.e., accessibility of the site, urgency for response, and quantity of material required; laboratory studies involving the release of oil under artificial sea ice in simulated ice formation and decay purposes to determine the interaction of crude oil and first-year sea ice; inability of companies and government to control a major spill in the Labrador Sea because of poor and inadequate transport facilities, communications, and navigational aids, severe environmental conditions, and logistics problems; and studies on the effects of oil-well blowouts in deep water, including formation of oil and gas hydrates, design of oil skimmers, the use of hovercraft, and specifications for an airborne multisensor system for oil detection in ice-infested waters.

  12. Exposing the structure of an arctic food web

    NARCIS (Netherlands)

    Wirta, Helena K; Vesterinen, Eero J; Hambäck, Peter A.; Weingartner, Elisabeth; Rasmussen, Claus; Reneerkens, Jeroen; Schmidt, Niels M; Gilg, Olivier; Roslin, Tomas

    2015-01-01

    How food webs are structured has major implications for their stability and dynamics. While poorly studied to date, arctic food webs are commonly assumed to be simple in structure, with few links per species. If this is the case, then different parts of the web may be weakly connected to each other,

  13. [PATTERNS IN CIRCULATION AND TRANSMISSION OF MARINE BIRD PARASITES IN HIGH ARCTIC: A CASE OF ACANTHOCEPHALAN POLYMORPHUS PHIPPSI (PALAEACANTHOCEPHALA, POLYMORPHIDAE)].

    Science.gov (United States)

    Galaktionov, K V; Atrashkevich, G I

    2015-01-01

    This study, based on the materials on parasitic infection of marine birds and invertebrates in Frantz Josef Land (FJL) collected in 1991-1993, focussed on the acanthocephalan Polymorphus phippsi. We identified this parasite, confirmed its species status and analysed its circulation and transmission patterns in high Arctic. The causes of its erroneous identification as P. minutus in several studies were also examined. In contrast to P. minutus, the transmission of P. phippsi is realized in marine coastal ecosystems. Its' main intermediate host in the Arctic is the amphipod Gammarus (Lagunogammarus) setosus, commonin coastal. areas of the shelf zone throughout the Arctic basin. P. phippsi population in FJL and the entire European Arctic is on the whole maintained by a single obligate final host, the common eider Somateria mollissima. Prevalence (P) of P. phippsi in this bird reached 100 %, with the maximal infection intensity (IImax) of 1188 and the mean abundance (MA) of 492.1. Other species of birds found to be infected with P. phippsi (Arctic turn, black guillemot, purple sandpiper and several gulls) are facultative and/or eliminative hosts. The most heavily infected birds were Arctic terns (P = 72.7%, IImax = 227, MA = = 47.1), which contained single mature acanthocephalans. For one of the FJL regions, infections flows of P. phippsi through various host categories were calculated. Involvement of birds unrelated to the common eider into the circulation of P. phippsi is facilitated by their feeding character in the Arctic. While coastal crustaceans are abundant, fish food is relatively scarce (polar cod, snailfishes), and so amphipods make up a considerable part of the diet of marine birds in FJL, if not most of it, as for instance in case of Arctic tern. This promotes an easy entry of the larvae of crustaceans-parasitizing helminthes (cestodes and acanthocephalans, including cystacanths P. phippsi) into non-specific hosts and opens broad colonization possibilities

  14. Polychlorinated naphthalenes (PCNs) in sub-Arctic and Arctic marine mammals, 1986–2009

    International Nuclear Information System (INIS)

    A selection of PCN congeners was analyzed in pooled blubber samples of pilot whale (Globicephala melas), ringed seal (Phoca hispida), minke whale (Balaenoptera acutorostrata), fin whale (Balaenoptera physalus), harbour porpoise (Phocoena phocoena), hooded seal (Cystophora cristata) and Atlantic white-sided dolphin (Lagenorhynchus acutus), covering a time period of more than 20 years (1986–2009). A large geographical area of the North Atlantic and Arctic areas was covered. PCN congeners 48, 52, 53, 66 and 69 were found in the blubber samples between 0.03 and 5.9 ng/g lw. Also PCBs were analyzed in minke whales and fin whales from Iceland and the total PCN content accounted for 0.2% or less of the total non-planar PCB content. No statistically significant trend in contaminant levels could be established for the studied areas. However, in all species except minke whales caught off Norway the lowest ∑PCN concentrations were found in samples from the latest sampling period. - Highlights: ► PCN concentrations are described in a wide variety of marine mammal species. ► A large geographical area of the North Atlantic and Arctic areas is covered. ► Pooled blubber samples covering a time period of 23 years are evaluated. ► Species- and geographic-dependent PCN congener distribution is seen. ► A decrease in the PCN load is indicated in the studied areas in recent years. - Analysis of PCNs in seven marine mammal species sampled over a 23 year period indicates a decline in the PCN load in sub-Arctic and Arctic areas in recent years.

  15. Exposing the structure of an Arctic food web.

    Science.gov (United States)

    Wirta, Helena K; Vesterinen, Eero J; Hambäck, Peter A; Weingartner, Elisabeth; Rasmussen, Claus; Reneerkens, Jeroen; Schmidt, Niels M; Gilg, Olivier; Roslin, Tomas

    2015-09-01

    How food webs are structured has major implications for their stability and dynamics. While poorly studied to date, arctic food webs are commonly assumed to be simple in structure, with few links per species. If this is the case, then different parts of the web may be weakly connected to each other, with populations and species united by only a low number of links. We provide the first highly resolved description of trophic link structure for a large part of a high-arctic food web. For this purpose, we apply a combination of recent techniques to describing the links between three predator guilds (insectivorous birds, spiders, and lepidopteran parasitoids) and their two dominant prey orders (Diptera and Lepidoptera). The resultant web shows a dense link structure and no compartmentalization or modularity across the three predator guilds. Thus, both individual predators and predator guilds tap heavily into the prey community of each other, offering versatile scope for indirect interactions across different parts of the web. The current description of a first but single arctic web may serve as a benchmark toward which to gauge future webs resolved by similar techniques. Targeting an unusual breadth of predator guilds, and relying on techniques with a high resolution, it suggests that species in this web are closely connected. Thus, our findings call for similar explorations of link structure across multiple guilds in both arctic and other webs. From an applied perspective, our description of an arctic web suggests new avenues for understanding how arctic food webs are built and function and of how they respond to current climate change. It suggests that to comprehend the community-level consequences of rapid arctic warming, we should turn from analyses of populations, population pairs, and isolated predator-prey interactions to considering the full set of interacting species. PMID:26380710

  16. Seasonal Changes in the Marine Production Cycles in Response to Changes in Arctic Sea Ice and Upper Ocean Circulation

    Science.gov (United States)

    Spitz, Y. H.; Ashjian, C. J.; Campbell, R. G.; Steele, M.; Zhang, J.

    2011-12-01

    Significant seasonal changes in arctic sea ice have been observed in recent years, characterized by unprecedented summer melt-back. As summer sea ice extent shrinks to record low levels, the peripheral seas of the Arctic Ocean are exposed much earlier to atmospheric surface heat flux, resulting in longer and warmer summers with more oceanic heat absorption. The changing seasonality in the arctic ice/ocean system will alter the timing, magnitude, duration, and pattern of marine production cycles by disrupting key trophic linkages and feedbacks in planktonic food webs. We are using a coupled pan-arctic Biology/Ice/Ocean Modeling and Assimilation System (BIOMAS) to investigate the changes in the patterns of seasonality in the arctic physical and biological system. Focus on specific regions of the Arctic, such as the Chukchi Sea, the Beaufort Sea and the adjacent central Arctic, reveals that changes in the timing of the spring bloom, its duration and the response of the secondary producers vary regionally. The major changes are, however, characterized by an earlier phytoplankton bloom and a slight increase of the biomass. In addition, the largest response in the secondary producers is seen in the magnitude of the microzooplankton concentration as well as in the period (early summer to late fall) over which the microzooplankton is present.

  17. Food enrichment with marine phospholipid emulsions

    DEFF Research Database (Denmark)

    Lu, Henna Fung Sieng; Nielsen, Nina Skall; Baron, Caroline P.;

    . The main objective of this study was to explore the possibilities of using marine PL for food enrichment. In order to achieve the objective, the study was divided into 4 stages: i) evaluation of physico-chemical properties of marine PL emulsions, ii) evaluation of hydrolytic and oxidative stability...... of marine PL emulsions, iii) evaluation of non-enzymatic browning reactions in marine PL emulsions, iv) evaluation of sensory properties and oxidative stability of yoghurt enriched with marine PL. The obtained results showed that marine PL have good emulsifying properties and it was feasible to prepare...... marine PL emulsions with and without addition of fish oil. The oxidative stability of marine PL emulsions was significantly influenced by the chemical composition of marine PL used for emulsions preparation. For instance, emulsions with good oxidative stability could be obtained when using raw materials...

  18. Influence of Sea Ice on Arctic Marine Sulfur Biogeochemistry in the Community Climate System Model

    Energy Technology Data Exchange (ETDEWEB)

    Deal, Clara [Univ. of Alaska, Fairbanks, AL (United States); Jin, Meibing [Univ. of Alaska, Fairbanks, AL (United States)

    2013-06-30

    Global climate models (GCMs) have not effectively considered how responses of arctic marine ecosystems to a warming climate will influence the global climate system. A key response of arctic marine ecosystems that may substantially influence energy exchange in the Arctic is a change in dimethylsulfide (DMS) emissions, because DMS emissions influence cloud albedo. This response is closely tied to sea ice through its impacts on marine ecosystem carbon and sulfur cycling, and the ice-albedo feedback implicated in accelerated arctic warming. To reduce the uncertainty in predictions from coupled climate simulations, important model components of the climate system, such as feedbacks between arctic marine biogeochemistry and climate, need to be reasonably and realistically modeled. This research first involved model development to improve the representation of marine sulfur biogeochemistry simulations to understand/diagnose the control of sea-ice-related processes on the variability of DMS dynamics. This study will help build GCM predictions that quantify the relative current and possible future influences of arctic marine ecosystems on the global climate system. Our overall research objective was to improve arctic marine biogeochemistry in the Community Climate System Model (CCSM, now CESM). Working closely with the Climate Ocean Sea Ice Model (COSIM) team at Los Alamos National Laboratory (LANL), we added 1 sea-ice algae and arctic DMS production and related biogeochemistry to the global Parallel Ocean Program model (POP) coupled to the LANL sea ice model (CICE). Both CICE and POP are core components of CESM. Our specific research objectives were: 1) Develop a state-of-the-art ice-ocean DMS model for application in climate models, using observations to constrain the most crucial parameters; 2) Improve the global marine sulfur model used in CESM by including DMS biogeochemistry in the Arctic; and 3) Assess how sea ice influences DMS dynamics in the arctic marine

  19. Marine Mammal Food Habits Reference Collections

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Marine Mammal Laboratory (NMML) Food Habits Reference Collection, containing over 8000 specimens of cephalopod beaks and fish bones and otoliths, is...

  20. Food consumption and growth of marine mammals.

    NARCIS (Netherlands)

    Kastelein, R.A.

    1998-01-01

    This thesis contains 35 studies on food consumption and growth of captive marine marinmals. Seventeen studies concern food intake and growth records of 9 odontocete species (toothed whales), varying in body weight from 30 to 4500 kg: the killer whale, beluga, false killer whale, Atlantic bottl

  1. Freshwater discharges drive high levels of methylmercury in Arctic marine biota.

    Science.gov (United States)

    Schartup, Amina T; Balcom, Prentiss H; Soerensen, Anne L; Gosnell, Kathleen J; Calder, Ryan S D; Mason, Robert P; Sunderland, Elsie M

    2015-09-22

    Elevated levels of neurotoxic methylmercury in Arctic food-webs pose health risks for indigenous populations that consume large quantities of marine mammals and fish. Estuaries provide critical hunting and fishing territory for these populations, and, until recently, benthic sediment was thought to be the main methylmercury source for coastal fish. New hydroelectric developments are being proposed in many northern ecosystems, and the ecological impacts of this industry relative to accelerating climate changes are poorly characterized. Here we evaluate the competing impacts of climate-driven changes in northern ecosystems and reservoir flooding on methylmercury production and bioaccumulation through a case study of a stratified sub-Arctic estuarine fjord in Labrador, Canada. Methylmercury bioaccumulation in zooplankton is higher than in midlatitude ecosystems. Direct measurements and modeling show that currently the largest methylmercury source is production in oxic surface seawater. Water-column methylation is highest in stratified surface waters near the river mouth because of the stimulating effects of terrestrial organic matter on methylating microbes. We attribute enhanced biomagnification in plankton to a thin layer of marine snow widely observed in stratified systems that concentrates microbial methylation and multiple trophic levels of zooplankton in a vertically restricted zone. Large freshwater inputs and the extensive Arctic Ocean continental shelf mean these processes are likely widespread and will be enhanced by future increases in water-column stratification, exacerbating high biological methylmercury concentrations. Soil flooding experiments indicate that near-term changes expected from reservoir creation will increase methylmercury inputs to the estuary by 25-200%, overwhelming climate-driven changes over the next decade.

  2. Food ingredients from the marine environment. Marine biotechnology meets food science and technology.

    Directory of Open Access Journals (Sweden)

    Ioannis S. Boziaris

    2014-11-01

    Full Text Available Marine environment disposes a plethora of bioactive compounds with unique properties and remarkable potential for biotechnological applications. A lot of those compounds can be used by the food industry as natural preservatives, pigments, stabilizers, gelling agents, etc., while others exhibits beneficial effects and can be used as functional food ingredients, nutraceuticals, dietary supplements and prebiotics. Interdisciplinary approach is required to increase our knowledge, explore the potential of marine environment and produce value-added food for all.

  3. Chromophoric Dissolved Organic Matter across a Marine Distributed Biological Observatory in the Pacific Arctic Region

    Science.gov (United States)

    Berman, S. L.; Frey, K. E.; Shake, K. L.; Cooper, L. W.; Grebmeier, J. M.

    2014-12-01

    Dissolved organic matter (DOM) plays an important role in marine ecosystems as both a carbon source for the microbial food web (and thus a source of CO2 to the atmosphere) and as a light inhibitor in marine environments. The presence of chromophoric dissolved organic matter (CDOM; the optically active portion of total DOM) can have significant controlling effects on transmittance of sunlight through the water column and therefore on primary production as well as the heat balance of the upper ocean. However, CDOM is also susceptible to photochemical degradation, which decreases the flux of solar radiation that is absorbed. Knowledge of the current spatial and temporal distribution of CDOM in marine environments is thus critical for understanding how ongoing and future changes in climate may impact these biological, biogeochemical, and physical processes. We describe the quantity and quality of CDOM along five key productive transects across a developing Distributed Biological Observatory (DBO) in the Pacific Arctic region. The samples were collected onboard the CCGS Sir Wilfred Laurier in July 2013 and 2014. Monitoring of the variability of CDOM along transects of high productivity can provide important insights into biological and biogeochemical cycling across the region. Our analyses include overall concentrations of CDOM, as well as proxy information such as molecular weight, lability, and source (i.e., autochthonous vs. allochthonous) of organic matter. We utilize these field observations to compare with satellite-derived CDOM concentrations determined from the Aqua MODIS satellite platform, which ultimately provides a spatially and temporally continuous synoptic view of CDOM concentrations throughout the region. Examining the current relationships among CDOM, sea ice variability, biological productivity, and biogeochemical cycling in the Pacific Arctic region will likely provide key insights for how ecosystems throughout the region will respond in future

  4. Status and trends in the structure of Arctic benthic food webs

    NARCIS (Netherlands)

    Kędra, M.; Moritz, C.; Choy, E.S.; David, C.; Degen, R.; Duerksen, S.; Ellingsen, I.; Górska, B.; Grebmeier, J.M.; Kirievskaya, D.; van Oevelen, D.; Piwosz, K.; Samuelsen, A.; We? slawski, J.M.

    2015-01-01

    Ongoing climate warming is causing a dramatic loss of sea ice in the Arctic Ocean, and it is projected that the Arctic Ocean will become seasonally ice-free by 2040. Many studies of local Arctic food webs now exist, and with this review paper we aim to synthesize these into a large-scale assessment

  5. Transfer of mercury in the marine food web of West Greenland.

    Science.gov (United States)

    Rigét, F; Møller, P; Dietz, R; Nielsen, T G; Asmund, G; Strand, J; Larsen, M M; Hobson, K A

    2007-08-01

    Total mercury (THg), methylmercury (MeHg) and stable isotopes of nitrogen (delta(15)N) and carbon (delta(13)C) were measured in three invertebrate, five fish, three seabird and three marine mammal species of central West Greenland to investigate trophic transfer of mercury in this Arctic marine food web. The food web magnification factor (FWMF) estimated as the slope of the regression between the natural logarithm of THg or MeHg concentrations (mg kg(-1) dw) and tissue delta(15)N ( per thousand) was estimated to 0.183 (SE = 0.052) for THg and 0.339 (SE = 0.075) for MeHg. The FWMFs were not only comparable with those reported for other Arctic marine food webs but also with quite different food webs such as freshwater lakes in the sub-Arctic, East Africa and Papua New Guinea. This suggests similar mechanisms of mercury assimilation and isotopic (delta(15)N) discrimination among a broad range of aquatic taxa and underlines the possibility of broad ecosystem comparisons using the combined contaminant and stable isotope approach. PMID:17671670

  6. Arctic marine climate of the early nineteenth century

    Directory of Open Access Journals (Sweden)

    P. Brohan

    2010-02-01

    Full Text Available The climate of the early nineteenth century is likely to have been significantly cooler than that of today, as it was a period of low solar activity (the Dalton minimum and followed a series of large volcanic eruptions. Proxy reconstructions of the temperature of the period do not agree well on the size of the temperature change, so other observational records from the period are particularly valuable. Weather observations have been extracted from the reports of the noted whaling captain William Scoresby Jr., and from the records of a series of Royal Navy expeditions to the Arctic, preserved in the UK National Archives. They demonstrate that marine climate in 1810–25 was marked by consistently cold summers, with abundant sea-ice. But although the period was significantly colder than the modern average, there was a lot of variability: in the Greenland Sea the summers following the Tambora eruption (1816 and 1817 were noticeably warmer, and had lower sea-ice coverage, than the years immediately preceding them; and the sea-ice coverage in Lancaster Sound in 1819 and 1820 was low even by modern standards.

  7. Arctic marine climate of the early nineteenth century

    Directory of Open Access Journals (Sweden)

    P. Brohan

    2010-05-01

    Full Text Available The climate of the early nineteenth century is likely to have been significantly cooler than that of today, as it was a period of low solar activity (the Dalton minimum and followed a series of large volcanic eruptions. Proxy reconstructions of the temperature of the period do not agree well on the size of the temperature change, so other observational records from the period are particularly valuable. Weather observations have been extracted from the reports of the noted whaling captain William Scoresby Jr., and from the records of a series of Royal Navy expeditions to the Arctic, preserved in the UK National Archives. They demonstrate that marine climate in 1810–1825 was marked by consistently cold summers, with abundant sea-ice. But although the period was significantly colder than the modern average, there was considerable variability: in the Greenland Sea the summers following the Tambora eruption (1816 and 1817 were noticeably warmer, and had less sea-ice coverage, than the years immediately preceding them; and the sea-ice coverage in Lancaster Sound in 1819 and 1820 was low even by modern standards.

  8. Arctic Small Rodents Have Diverse Diets and Flexible Food Selection.

    Directory of Open Access Journals (Sweden)

    Eeva M Soininen

    Full Text Available The ecology of small rodent food selection is poorly understood, as mammalian herbivore food selection theory has mainly been developed by studying ungulates. Especially, the effect of food availability on food selection in natural habitats where a range of food items are available is unknown. We studied diets and selectivity of grey-sided voles (Myodes rufocanus and tundra voles (Microtus oeconomus, key herbivores in European tundra ecosystems, using DNA metabarcoding, a novel method enabling taxonomically detailed diet studies. In order to cover the range of food availabilities present in the wild, we employed a large-scale study design for sampling data on food availability and vole diets. Both vole species had ingested a range of plant species and selected particularly forbs and grasses. Grey-sided voles also selected ericoid shrubs and tundra voles willows. Availability of a food item rarely affected its utilization directly, although seasonal changes of diets and selection suggest that these are positively correlated with availability. Moreover, diets and selectivity were affected by availability of alternative food items. These results show that the focal sub-arctic voles have diverse diets and flexible food preferences and rarely compensate low availability of a food item with increased searching effort. Diet diversity itself is likely to be an important trait and has previously been underrated owing to methodological constraints. We suggest that the roles of alternative food item availability and search time limitations for small rodent feeding ecology should be investigated.Annotated Checklist of the Panarctic Flora (PAF, Vascular plants. Available at: http://nhm2.uio.no/paf/, accessed 15.6.2012.

  9. Arctic marine gravity and bathymetry from 3 years of Cryosat-2 SAR altimetry (DTU13 Gravity)

    DEFF Research Database (Denmark)

    Andersen, Ole Baltazar; Stenseng, Lars; Knudsen, Per;

    The accuracy of the Arctic marine gravity field has for many been severely limited by the availability and accuracy of altimeter data in the Arctic Ocean. Until recently only ERS-1 provided non-repeat (0.9 year) geodetic mission altimetry in the Arctic Ocean and only up to 82N. With the launch...... of Cryosat-2 three years ago a new source of high quality altimetric data has become available. The Cryosat-2 delay Doppler altimeter offers a factor of 20 improvements in along track resolution, an along-track footprint length that does not vary with wave height (sea state) and at least a factor of two......1 SAR altimetry in the Arctic Ocean for gravity field determination. Extensive testing, interpretation and improvement of methods to handles the new class of data has been investigated and the first result from a new Arctic Ocean wide gravity field will be presented as well as initial test...

  10. Selective processes for bioaccumulative up-take of persistent organic pollutants (POPs) in Arctic food webs

    OpenAIRE

    Carlsson, Pernilla Marianne

    2013-01-01

    The overall aim of the present study was to elucidate selective environmental up-take processes in Arctic food webs that lead to the bioaccumulation of persistent organic pollutants (POP) in food items consumed by Arctic indigenous people. In addition, this study aimed to increase the scientific understanding of the principles behind climate change related influences on transport processes of contaminants. Svalbard and Nuuk, Greenland were chosen as study areas since they represent Arctic con...

  11. Impact of CryoSat-2 for marine gravity field - globally and in the Arctic Ocean

    DEFF Research Database (Denmark)

    Andersen, Ole Baltazar; Stenseng, Lars; Knudsen, Per;

    days repeat offered by CryoSat-2 provides denser coverage than older geodetic mission data set like ERS-1. Thirdly, the 92 degree inclination of CryoSat-2 is designed to map more of the Arctic Ocean than previous altimetric satellites. Finally, CryoSat-2 is able to operate in two new modes (SAR and SAR...... GDR data, NOAA LRM data, but also Level1b (LRM, SAR and SAR-in waveforms) data have been analyzed. A suite of eight different empirical retrackers have been developed and investigated for their ability to predict marine gravity in the Arctic Ocean. The impact of the various improvement offered by Cryo......Sat-2 in comparison with conventional satellite altimetry have been studied and quantified both globally but particularly for the Arctic Ocean using a large number of marine and airborne surveys providing “ground truth” marine gravity....

  12. The delivery of organic contaminants to the Arctic food web: why sea ice matters.

    Science.gov (United States)

    Pućko, Monika; Stern, Gary A; Macdonald, Robie W; Jantunen, Liisa M; Bidleman, Terry F; Wong, Fiona; Barber, David G; Rysgaard, Søren

    2015-02-15

    For decades sea ice has been perceived as a physical barrier for the loading of contaminants to the Arctic Ocean. We show that sea ice, in fact, facilitates the delivery of organic contaminants to the Arctic marine food web through processes that: 1) are independent of contaminant physical-chemical properties (e.g. 2-3-fold increase in exposure to brine-associated biota), and 2) depend on physical-chemical properties and, therefore, differentiate between contaminants (e.g. atmospheric loading of contaminants to melt ponds over the summer, and their subsequent leakage to the ocean). We estimate the concentrations of legacy organochlorine pesticides (OCPs) and current-use pesticides (CUPs) in melt pond water in the Beaufort Sea, Canadian High Arctic, in 2008, at near-gas exchange equilibrium based on Henry's law constants (HLCs), air concentrations and exchange dynamics. CUPs currently present the highest risk of increased exposures through melt pond loading and drainage due to the high ratio of melt pond water to seawater concentration (Melt pond Enrichment Factor, MEF), which ranges from 2 for dacthal to 10 for endosulfan I. Melt pond contaminant enrichment can be perceived as a hypothetical 'pump' delivering contaminants from the atmosphere to the ocean under ice-covered conditions, with 2-10% of CUPs annually entering the Beaufort Sea via this input route compared to the standing stock in the Polar Mixed Layer of the ocean. The abovementioned processes are strongly favored in first-year ice compared to multi-year ice and, therefore, the dynamic balance between contaminant inventories and contaminant deposition to the surface ocean is being widely affected by the large-scale icescape transition taking place in the Arctic. PMID:25437762

  13. The delivery of organic contaminants to the Arctic food web: why sea ice matters.

    Science.gov (United States)

    Pućko, Monika; Stern, Gary A; Macdonald, Robie W; Jantunen, Liisa M; Bidleman, Terry F; Wong, Fiona; Barber, David G; Rysgaard, Søren

    2015-02-15

    For decades sea ice has been perceived as a physical barrier for the loading of contaminants to the Arctic Ocean. We show that sea ice, in fact, facilitates the delivery of organic contaminants to the Arctic marine food web through processes that: 1) are independent of contaminant physical-chemical properties (e.g. 2-3-fold increase in exposure to brine-associated biota), and 2) depend on physical-chemical properties and, therefore, differentiate between contaminants (e.g. atmospheric loading of contaminants to melt ponds over the summer, and their subsequent leakage to the ocean). We estimate the concentrations of legacy organochlorine pesticides (OCPs) and current-use pesticides (CUPs) in melt pond water in the Beaufort Sea, Canadian High Arctic, in 2008, at near-gas exchange equilibrium based on Henry's law constants (HLCs), air concentrations and exchange dynamics. CUPs currently present the highest risk of increased exposures through melt pond loading and drainage due to the high ratio of melt pond water to seawater concentration (Melt pond Enrichment Factor, MEF), which ranges from 2 for dacthal to 10 for endosulfan I. Melt pond contaminant enrichment can be perceived as a hypothetical 'pump' delivering contaminants from the atmosphere to the ocean under ice-covered conditions, with 2-10% of CUPs annually entering the Beaufort Sea via this input route compared to the standing stock in the Polar Mixed Layer of the ocean. The abovementioned processes are strongly favored in first-year ice compared to multi-year ice and, therefore, the dynamic balance between contaminant inventories and contaminant deposition to the surface ocean is being widely affected by the large-scale icescape transition taking place in the Arctic.

  14. Bacterial production and microbial food web structure in a large arctic river and the coastal Arctic Ocean

    Science.gov (United States)

    Vallières, Catherine; Retamal, Leira; Ramlal, Patricia; Osburn, Christopher L.; Vincent, Warwick F.

    2008-12-01

    Globally significant quantities of organic carbon are stored in northern permafrost soils, but little is known about how this carbon is processed by microbial communities once it enters rivers and is transported to the coastal Arctic Ocean. As part of the Arctic River-Delta Experiment (ARDEX), we measured environmental and microbiological variables along a 300 km transect in the Mackenzie River and coastal Beaufort Sea, in July-August 2004. Surface bacterial concentrations averaged 6.7 × 10 5 cells mL - 1 with no significant differences between sampling zones. Picocyanobacteria were abundant in the river, and mostly observed as cell colonies. Their concentrations in the surface waters decreased across the salinity gradient, dropping from 51,000 (river) to 30 (sea) cells mL - 1 . There were accompanying shifts in protist community structure, from diatoms, cryptophytes, heterotrophic protists and chrysophytes in the river, to dinoflagellates, prymnesiophytes, chrysophytes, prasinophytes, diatoms and heterotrophic protists in the Beaufort Sea. Size-fractionated bacterial production, as measured by 3H-leucine uptake, varied from 76 to 416 ng C L - 1 h - 1 . The contribution of particle-attached bacteria (> 3 µm fraction) to total bacterial production decreased from > 90% at the Mackenzie River stations to importance of this particle-based fraction was inversely correlated with salinity and positively correlated with particulate organic carbon concentrations. Glucose enrichment experiments indicated that bacterial metabolism was carbon limited in the Mackenzie River but not in the coastal ocean. Prior exposure of water samples to full sunlight increased the biolability of dissolved organic carbon (DOC) in the Mackenzie River but decreased it in the Beaufort Sea. Estimated depth-integrated bacterial respiration rates in the Mackenzie River were higher than depth-integrated primary production rates, while at the marine stations bacterial respiration rates were near or

  15. Foreword to the thematic cluster: the Arctic in Rapid Transition—marine ecosystems

    Directory of Open Access Journals (Sweden)

    Monika Kędra

    2015-12-01

    Full Text Available The Arctic is warming and losing sea ice. Happening at a much faster rate than previously expected, these changes are causing multiple ecosystem feedbacks in the Arctic Ocean. The Arctic in Rapid Transition (ART initiative was developed by early-career scientists as an integrative, international, multidisciplinary, long-term pan-Arctic network to study changes and feedbacks among the physical and biogeochemical components of the Arctic Ocean and their ultimate impacts on biological productivity on different timescales. In 2012, ART jointly organized with the Association of Polar Early Career Scientists their second science workshop—Overcoming Challenges of Observation to Model Integration in Marine Ecosystem Response to Sea Ice Transitions—at the Institute of Oceanology, Polish Academy of Sciences, in Sopot. This workshop aimed to identify linkages and feedbacks between atmosphere–ice–ocean forcing and biogeochemical processes, which are critical for ecosystem function, land–ocean interactions and productive capacity of the Arctic Ocean. This special thematic cluster of Polar Research brings together seven papers that grew out of workgroup discussions. Papers examine the climate change impacts on various ecosystem elements, providing important insights on the marine ecological and biogeochemical processes on various timescales. They also highlight priority areas for future research.

  16. Marine Mammals and Climate Change in the Pacific Arctic: Impacts & Resilience

    Science.gov (United States)

    Moore, S. E.

    2014-12-01

    Extreme reductions in Arctic sea ice extent and thickness have become a hallmark of climate change, but impacts to the marine ecosystem are poorly understood. As top predators, marine mammals must adapt to biological responses to physical forcing and thereby become sentinels to ecosystem variability and reorganization. Recent sea ice retreats have influenced the ecology of marine mammals in the Pacific Arctic sector. Walruses now often haul out by the thousands along the NW Alaska coast in late summer, and reports of harbor porpoise, humpback, fin and minke whales in the Chukchi Sea demonstrate that these temperate species routinely occur there. In 2010, satellite tagged bowhead whales from Atlantic and Pacific populations met in the Northwest Passage, an overlap thought precluded by sea ice since the Holocene. To forage effectively, baleen whales must target dense patches of zooplankton and small fishes. In the Pacific Arctic, bowhead and gray whales appear to be responding to enhanced prey availability delivered both by new production and advection pathways. Two programs, the Distributed Biological Observatory (DBO) and the Synthesis of Arctic Research (SOAR), include tracking of marine mammal and prey species' responses to ecosystem shifts associated with sea ice loss. Both programs provide an integrated-ecosystem baseline in support of the development of a web-based Marine Mammal Health Map, envisioned as a component of the U.S. Integrated Ocean Observing System (IOOS). An overarching goal is to identify ecological patterns for marine mammals in the 'new' Arctic, as a foundation for integrative research, local response and adaptive management.

  17. Community size and metabolic rates of psychrophilic sulfate-reducing bacteria in Arctic marine sediments

    DEFF Research Database (Denmark)

    Knoblauch, C.; Jørgensen, BB; Harder, J.

    1999-01-01

    of 19 isolated psychrophiles were compared to corresponding rates of 9 marine, mesophilic sulfate-reducing bacteria. The results indicate that, as a physiological adaptation to the permanently cold Arctic environment, psychrophilic sulfate reducers have considerably higher specific metabolic rates than...

  18. Spatial issues in Arctic marine resource governance workshop summary and comment

    DEFF Research Database (Denmark)

    Kaiser, Brooks; Bakanev, Sergey; Bertelsen, Rasmus Gjedssø;

    2015-01-01

    The rapidly changing Arctic marine ecosystems face new challenges and opportunities that are increasing and shifting governance needs in the region. A group of economists, ecologists, biologists, political scientists and resource managers met in Stockholm, SE, Sept 4–6, 2014 to discuss...

  19. Spatial isses in Arctic marine resource governance workshop summary and comment

    DEFF Research Database (Denmark)

    Kaiser, Brooks; Bakanev, Sergey; Bertelsen, Rasmus;

    2015-01-01

    The rapidly changing Arctic marine ecosystems face new challenges and opportunities that are increasing and shifting governance needs in the region. A group of economists, ecologists, biologists, political scientists and resource managers met in Stockholm, SE, Sept 4–6, 2014 to discuss...

  20. Thermophilic anaerobes in arctic marine sediments induced to mineralize complex organic matter at high temperature

    DEFF Research Database (Denmark)

    Hubert, Casey; Arnosti, Carol; Brüchert, Volker;

    2010-01-01

    Marine sediments harbour diverse populations of dormant thermophilic bacterial spores that become active in sediment incubation experiments at much higher than in situ temperature. This response was investigated in the presence of natural complex organic matter in sediments of two Arctic fjords, ...

  1. Pan-Arctic concentrations of mercury and stable isotope ratios of carbon (δ(13)C) and nitrogen (δ(15)N) in marine zooplankton.

    Science.gov (United States)

    Pomerleau, Corinne; Stern, Gary A; Pućko, Monika; Foster, Karen L; Macdonald, Robie W; Fortier, Louis

    2016-05-01

    Zooplankton play a central role in marine food webs, dictating the quantity and quality of energy available to upper trophic levels. They act as "keystone" species in transfer of mercury (Hg) up through the marine food chain. Here, we present the first Pan-Arctic overview of total and monomethylmercury concentrations (THg and MMHg) and stable isotope ratios of carbon (δ(13)C) and nitrogen (δ(15)N) in selected zooplankton species by assembling data collected between 1998 and 2012 from six arctic regions (Laptev Sea, Chukchi Sea, southeastern Beaufort Sea, Canadian Arctic Archipelago, Hudson Bay and northern Baffin Bay). MMHg concentrations in Calanus spp., Themisto spp. and Paraeuchaeta spp. were found to increase with higher δ(15)N and lower δ(13)C. The southern Beaufort Sea exhibited both the highest THg and MMHg concentrations. Biomagnification of MMHg between Calanus spp. and two of its known predators, Themisto spp. and Paraeuchaeta spp., was greatest in the southern Beaufort Sea. Our results show large geographical variations in Hg concentrations and isotopic signatures for individual species related to regional ecosystem features, such as varying water masses and freshwater inputs, and highlight the increased exposure to Hg in the marine food chain of the southern Beaufort Sea. PMID:26874765

  2. Assessment of consumption of marine food in Greenland by a food frequency questionnaire and biomarkers

    DEFF Research Database (Denmark)

    Jeppesen, Charlotte; Jørgensen, Marit Eika; Bjerregaard, Peter

    2012-01-01

    We studied the association and agreement between questionnaire data and biomarkers of marine food among Greenland Inuit.......We studied the association and agreement between questionnaire data and biomarkers of marine food among Greenland Inuit....

  3. Food ingredients from the marine environment. Marine biotechnology meets food science and technology.

    OpenAIRE

    Ioannis S. Boziaris

    2014-01-01

    Marine environment disposes a plethora of bioactive compounds with unique properties and remarkable potential for biotechnological applications. A lot of those compounds can be used by the food industry as natural preservatives, pigments, stabilizers, gelling agents, etc., while others exhibits beneficial effects and can be used as functional food ingredients, nutraceuticals, dietary supplements and prebiotics. Interdisciplinary approach is required to increase our knowledge, explore the pote...

  4. Food ingredients from the marine environment. Marine biotechnology meets food science and technology

    OpenAIRE

    Ioannis S. Boziaris

    2014-01-01

    Marine environment affords a plethora of bioactive compounds with unique properties and remarkable potential for biotechnological applications. A lot of those compounds can be used by the food industry as natural preservatives, pigments, stabilizers, gelling agents, and others, while others exhibit beneficial effects and can be used as functional food ingredients, nutraceuticals, dietary supplements and prebiotics. Interdisciplinary approach is required to increase our knowledge, explore the ...

  5. Indicators of food and water security in an Arctic Health context - results from an international workshop discussion

    OpenAIRE

    Nilsson, Lena Maria; Berner, James; Dudarev, Alexey A.; Mulvad, Gert; Odland, Jon Øyvind; Parkinson, Alan J.; Rautio, Arja; Tikhonov, Constantine; Evengård, Birgitta

    2013-01-01

    In August 2012, a literature search with the aim of describing indicators on food and water security in an Arctic health context was initialized in collaboration between the Arctic Human Health Expert Group, SDWG/AHHEG and the AMAP (Arctic Monitoring and Assessment Programme within the Arctic Council) Human Health Assessment Group, AMAP/HHAG. In December 2012, workshop discussions were performed with representatives from both of these organizations, including 7 Arctic countries. The aim of th...

  6. Marine Invasive Species Management: Adapting in the Arctic

    DEFF Research Database (Denmark)

    Kaiser, Brooks

    2014-01-01

    perturbations in the fragile Arctic ecosystems are likely to have outsized impacts both ecologically and economically. This paper discusses the optimal management of invasive species threats as a process that begins before the arrival of any species, with prevention, and continues in an integrated fashion...

  7. Future Arctic marine access: analysis and evaluation of observations, models, and projections of sea ice

    Directory of Open Access Journals (Sweden)

    T. S. Rogers

    2013-02-01

    Full Text Available There is an emerging need for regional applications of sea ice projections to provide more accuracy and greater detail to scientists, national, state and local planners, and other stakeholders. The present study offers a prototype for a comprehensive, interdisciplinary study to bridge observational data, climate model simulations, and user needs. The study's first component is an observationally based evaluation of Arctic sea ice trends during 1980–2008, with an emphasis on seasonal and regional differences relative to the overall pan-Arctic trend. Regional sea ice loss has varied, with a significantly larger decline of winter maximum (January–March extent in the Atlantic region than in other sectors. A lead–lag regression analysis of Atlantic sea ice extent and ocean temperatures indicates that reduced sea ice extent is associated with increased Atlantic Ocean temperatures. Correlations between the two variables are greater when ocean temperatures lag rather than lead sea ice. The performance of 13 global climate models is evaluated using three metrics to compare sea ice simulations with the observed record. We rank models over the pan-Arctic domain and regional quadrants and synthesize model performance across several different studies. The best performing models project reduced ice cover across key access routes in the Arctic through 2100, with a lengthening of seasons for marine operations by 1–3 months. This assessment suggests that the Northwest and Northeast Passages hold potential for enhanced marine access to the Arctic in the future, including shipping and resource development opportunities.

  8. Future Arctic marine access: analysis and evaluation of observations, models, and projections of sea ice

    Directory of Open Access Journals (Sweden)

    T. S. Rogers

    2012-09-01

    Full Text Available There is an emerging need for regional applications of sea ice projections to provide more accuracy and greater detail to scientists, national, state and local planners, and other stakeholders. The present study offers a prototype for a comprehensive, interdisciplinary study to bridge observational data, climate model simulations, and user needs. The study's first component is an observationally-based evaluation of Arctic sea ice trends during 1980–2008, with an emphasis on seasonal and regional differences relative to the overall pan-Arctic trend. Regional sea ice los has varied, with a significantly larger decline of winter maximum (January–March extent in the Atlantic region than in other sectors. A lead-lag regression analysis of Atlantic sea ice extent and ocean temperatures indicates that reduced sea ice extent is associated with increased Atlantic Ocean temperatures. Correlations between the two variables are greater when ocean temperatures lag rather than lead sea ice. The performance of 13 global climate models is evaluated using three metrics to compare sea ice simulations with the observed record. We rank models over the pan-Arctic domain and regional quadrants, and synthesize model performance across several different studies. The best performing models project reduced ice cover across key access routes in the Arctic through 2100, with a lengthening of seasons for marine operations by 1–3 months. This assessment suggests that the Northwest and Northeast Passages hold potential for enhanced marine access to the Arctic in the future, including shipping and resource development opportunities.

  9. Levels and temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard in relation to dietary habits and food availability.

    Science.gov (United States)

    Andersen, Martin S; Fuglei, Eva; König, Max; Lipasti, Inka; Pedersen, Åshild Ø; Polder, Anuschka; Yoccoz, Nigel G; Routti, Heli

    2015-04-01

    Temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard, Norway, were investigated in relation to feeding habits and seasonal food availability. Arctic foxes from Svalbard forage in both marine and terrestrial ecosystems and the availability of their food items are impacted by climatic variability. Concentrations of polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and brominated flame retardants (polybrominated diphenyl ethers [PBDEs] and hexabromocyclododecane [HBCDD]) were analyzed in the liver of 141 arctic foxes collected between 1997 and 2013. Stable carbon isotope values (δ13C) were used as a proxy for feeding on marine versus terrestrial prey. The annual number of recovered reindeer carcasses and sea ice cover were used as proxies for climate influenced food availability (reindeers, seals). Linear models revealed that concentrations of PCBs, chlordanes, p,p'-DDE, mirex and PBDEs decreased 4-11% per year, while no trends were observed for hexachlorobenzene (HCB) or β-hexachlorocyclohexane (β-HCH). Positive relationships between POP concentrations and δ13C indicate that concentrations of all compounds increase with increasing marine dietary input. Increasing reindeer mortality was related to lower HCB concentrations in the foxes based on the linear models. This suggests that concentrations of HCB in arctic foxes may be influenced by high mortality levels of Svalbard reindeer. Further, β-HCH concentrations showed a positive association with sea ice cover. These results in addition to the strong effect of δ13C on all POP concentrations suggest that climate-related changes in arctic fox diet are likely to influence contaminant concentrations in arctic foxes from Svalbard. PMID:25536177

  10. Hotspots in cold seas: The composition, distribution, and abundance of marine birds in the North American Arctic

    Science.gov (United States)

    Wong, Sarah N. P.; Gjerdrum, Carina; Morgan, Ken H.; Mallory, Mark L.

    2014-03-01

    The distribution and thickness of sea ice in the Arctic is changing rapidly, resulting in changes to Arctic marine ecosystems. Seabirds are widely regarded as indicators of marine environmental change, and understanding their distribution patterns can serve as a tool to monitor and elucidate biological changes in the Arctic seas. We examined the at-sea distribution of seabirds in the North American Arctic in July and August, 2007-2012, and marine areas of high density were identified based on bird densities for four foraging guilds. Short-tailed shearwaters (Puffinus tenuirostris) were the most abundant species observed. Northern fulmars (Fulmarus glacialis), thick-billed murres (Uria lomvia), and dovekies (Alle alle) were also sighted in large numbers. Few birds were sighted between Dolphin and Union Strait and King William Island. Areas of high density over multiple years were found throughout the entire western portion of the study area (Bering Sea, Bering Strait, and Chukchi Sea), Lancaster Sound, Baffin Bay, Davis Strait, and the low Arctic waters off Newfoundland. These waters are characterized by high primary productivity. This study is the first to document the marine distribution of seabirds across the entire North American Arctic within the same time period, providing a critical baseline for monitoring the distribution and abundance of Arctic seabirds in a changing Arctic seascape.

  11. Comparative analysis of marine paleogene sections and biota from West Siberia and the Arctic Region

    Science.gov (United States)

    Akhmet'ev, M. A.; Zaporozhets, N. I.; Iakovleva, A. I.; Aleksandrova, G. N.; Beniamovsky, V. N.; Oreshkina, T. V.; Gnibidenko, Z. N.; Dolya, Zh. A.

    2010-12-01

    The analysis of the main biospheric events that took place in West Siberia and the Arctic region during the Early Paleogene revealed the paleogeographic and paleobiogeographic unity of marine sedimentation basins and close biogeographic relations between their separate parts. Most biotic and abiotic events of the first half of the Paleogene in the Arctic region and West Siberia were synchronous, unidirectional, and interrelated. Shelf settings, sedimentation breaks, and microfaunal assemblages characteristic of these basins during the Paleogene are compared. The comparative analysis primarily concerned events of the Paleocene-Eocene thermal maximum (PETM) and beds with Azolla (aquatic fern). The formation of the Eocene Azolla Beds in the Arctic region and West Siberia was asynchronous, although it proceeded in line with a common scenario related to the development of a system of estuarine-type currents in a sea basin partly isolated from the World Ocean.

  12. Levels and temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard in relation to dietary habits and food availability

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Martin S. [Norwegian Polar Institute, Fram Centre, NO-9296 Tromsø (Norway); Department of Arctic and Marine Biology, UiT The Arctic University of Norway, NO-9037 Tromsø (Norway); Fuglei, Eva; König, Max [Norwegian Polar Institute, Fram Centre, NO-9296 Tromsø (Norway); Lipasti, Inka [Department of Biology, University of Eastern Finland, FI-80101 Joensuu (Finland); Pedersen, Åshild Ø. [Norwegian Polar Institute, Fram Centre, NO-9296 Tromsø (Norway); Polder, Anuschka [Department of Food Safety and Infection Biology, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Ås (Norway); Yoccoz, Nigel G. [Department of Arctic and Marine Biology, UiT The Arctic University of Norway, NO-9037 Tromsø (Norway); Routti, Heli, E-mail: heli.routti@npolar.no [Norwegian Polar Institute, Fram Centre, NO-9296 Tromsø (Norway)

    2015-04-01

    Temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard, Norway, were investigated in relation to feeding habits and seasonal food availability. Arctic foxes from Svalbard forage in both marine and terrestrial ecosystems and the availability of their food items are impacted by climatic variability. Concentrations of polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and brominated flame retardants (polybrominated diphenyl ethers [PBDEs] and hexabromocyclododecane [HBCDD]) were analyzed in the liver of 141 arctic foxes collected between 1997 and 2013. Stable carbon isotope values (δ{sup 13}C) were used as a proxy for feeding on marine versus terrestrial prey. The annual number of recovered reindeer carcasses and sea ice cover were used as proxies for climate influenced food availability (reindeers, seals). Linear models revealed that concentrations of PCBs, chlordanes, p,p′-DDE, mirex and PBDEs decreased 4–11% per year, while no trends were observed for hexachlorobenzene (HCB) or β-hexachlorocyclohexane (β-HCH). Positive relationships between POP concentrations and δ{sup 13}C indicate that concentrations of all compounds increase with increasing marine dietary input. Increasing reindeer mortality was related to lower HCB concentrations in the foxes based on the linear models. This suggests that concentrations of HCB in arctic foxes may be influenced by high mortality levels of Svalbard reindeer. Further, β-HCH concentrations showed a positive association with sea ice cover. These results in addition to the strong effect of δ{sup 13}C on all POP concentrations suggest that climate-related changes in arctic fox diet are likely to influence contaminant concentrations in arctic foxes from Svalbard. - Highlights: • POPs were analyzed in the arctic foxes' liver (n = 141) from Svalbard collected in 1997–2013. • PCBs, chlordanes, p,p′-DDE, mirex and PBDEs decreased 4–11% per year.

  13. Levels and temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard in relation to dietary habits and food availability

    International Nuclear Information System (INIS)

    Temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard, Norway, were investigated in relation to feeding habits and seasonal food availability. Arctic foxes from Svalbard forage in both marine and terrestrial ecosystems and the availability of their food items are impacted by climatic variability. Concentrations of polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and brominated flame retardants (polybrominated diphenyl ethers [PBDEs] and hexabromocyclododecane [HBCDD]) were analyzed in the liver of 141 arctic foxes collected between 1997 and 2013. Stable carbon isotope values (δ13C) were used as a proxy for feeding on marine versus terrestrial prey. The annual number of recovered reindeer carcasses and sea ice cover were used as proxies for climate influenced food availability (reindeers, seals). Linear models revealed that concentrations of PCBs, chlordanes, p,p′-DDE, mirex and PBDEs decreased 4–11% per year, while no trends were observed for hexachlorobenzene (HCB) or β-hexachlorocyclohexane (β-HCH). Positive relationships between POP concentrations and δ13C indicate that concentrations of all compounds increase with increasing marine dietary input. Increasing reindeer mortality was related to lower HCB concentrations in the foxes based on the linear models. This suggests that concentrations of HCB in arctic foxes may be influenced by high mortality levels of Svalbard reindeer. Further, β-HCH concentrations showed a positive association with sea ice cover. These results in addition to the strong effect of δ13C on all POP concentrations suggest that climate-related changes in arctic fox diet are likely to influence contaminant concentrations in arctic foxes from Svalbard. - Highlights: • POPs were analyzed in the arctic foxes' liver (n = 141) from Svalbard collected in 1997–2013. • PCBs, chlordanes, p,p′-DDE, mirex and PBDEs decreased 4–11% per year. • Concentrations of

  14. Pollution of the Marine Environment by Dumping: Legal Framework Applicable to Dumped Chemical Weapons and Nuclear Waste in the Arctic Ocean

    OpenAIRE

    Lott, Alexander

    2016-01-01

    The Arctic seas are the world’s biggest dumping ground for sea-disposed nuclear waste and have served among the primary disposal sites for chemical warfare agents. Despite of scientific uncertainty, the Arctic Council has noted that this hazardous waste still affects adversely the Arctic marine environment and may have implications to the health of the Arctic people. The purpose of this manuscript is to establish the rights and obligations of the Arctic States in c...

  15. In Situ burning of Arctic marine oil spills

    DEFF Research Database (Denmark)

    Fritt-Rasmussen, Janne

    Oil spills in ice filled and Arctic waters pose other challenges for oil spill response compared to open and temperate waters. In situ burning has been proven to be an effective oil spill response method for oil spills in ice filled waters. This thesis presents results from laboratory and field...... experiments where the ignitability of oil spill as a function of oil type and weathering conditions (time/ice) was tested. The results show that the composition of the oil and the ice cover is important for the in situ burning time-window. The results were used to develop an algorithm that was implemented...

  16. Balancing the benefits and costs of traditional food substitution by indigenous Arctic women of childbearing age: Impacts on persistent organic pollutant, mercury, and nutrient intakes.

    Science.gov (United States)

    Binnington, Matthew J; Curren, Meredith S; Chan, Hing Man; Wania, Frank

    2016-09-01

    For indigenous Arctic Canadians, traditional food consumption represents a key source of nutrients and environmental contaminants. Particularly, ingestion of marine mammal blubber and meat may lead to persistent organic pollutant levels and mercury intakes that exceed regulatory thresholds for sensitive populations. We investigated whether temporary adjustments to the consumption of traditional food derived from marine mammals appreciably impacted contaminant exposure and nutrient intakes among indigenous women of childbearing age. Such adjustments can be motivated by the desire to lower contaminant exposure or to increase nutrition, or by the diminishing availability of other traditional food sources. We combined the contaminant fate and transport model GloboPOP with the food chain bioaccumulation model ACC-Human Arctic to simulate polychlorinated biphenyl exposures in female 2007-08 Inuit Health Survey participants. We also calculated daily mercury and nutrient intake rates. Our results suggest that a temporary decrease in marine mammal consumption is largely ineffective at reducing exposure to polychlorinated biphenyls, because of their long elimination half-lives. In contrast, substitution of marine mammals was highly efficient at reducing mercury intake, but also appreciably lowered intakes of iron, manganese, selenium, and ω-3 polyunsaturated fatty acids. The impact of increasing intake of traditional food derived from marine mammals during childbearing age greatly depended on baseline consumption rates; replacement is ill-advised for those who already consume a lot of traditional food due to greater polychlorinated biphenyl and mercury exposures, while replacement was potentially beneficial for those with very limited marine mammal consumption due to increased nutrient intakes. Our calculations primarily suggest that considering baseline traditional food intake rates is critical to devising reproductive dietary adjustment strategies that maximize nutrient

  17. Plutonium in the Arctic Marine Environment — A Short Review

    Directory of Open Access Journals (Sweden)

    Lindis Skipperud

    2004-01-01

    Full Text Available Anthropogenic plutonium has been introduced into the environment over the past 50 years as the result of the detonation of nuclear weapons and operational releases from the nuclear industry. In the Arctic environment, the main source of plutonium is from atmospheric weapons testing, which has resulted in a relatively uniform, underlying global distribution of plutonium. Previous studies of plutonium in the Kara Sea have shown that, at certain sites, other releases have given rise to enhanced local concentrations. Since different plutonium sources are characterised by distinctive plutonium-isotope ratios, evidence of a localised influence can be supported by clear perturbations in the plutonium-isotope ratio fingerprints as compared to the known ratio in global fallout. In Kara Sea sites, such perturbations have been observed as a result of underwater weapons tests at Chernaya Bay, dumped radioactive waste in Novaya Zemlya, and terrestrial runoff from the Ob and Yenisey Rivers. Measurement of the plutonium-isotope ratios offers both a means of identifying the origin of radionuclide contamination and the influence of the various nuclear installations on inputs to the Arctic, as well as a potential method for following the movement of water and sediment loads in the rivers.

  18. NOAA Atmospheric, Marine and Arctic Monitoring Using UASs (including Rapid Response)

    Science.gov (United States)

    Coffey, J. J.; Jacobs, T.

    2015-12-01

    Unmanned systems have the potential to efficiently, effectively, economically, and safely bridge critical observation requirements in an environmentally friendly manner. As the United States' Atmospheric, Marine and Arctic areas of interest expand and include hard-to-reach regions of the Earth (such as the Arctic and remote oceanic areas) optimizing unmanned capabilities will be needed to advance the United States' science, technology and security efforts. Through increased multi-mission and multi-agency operations using improved inter-operable and autonomous unmanned systems, the research and operations communities will better collect environmental intelligence and better protect our Country against hazardous weather, environmental, marine and polar hazards. This presentation will examine NOAA's Atmospheric, Marine and Arctic Monitoring Unmanned Aircraft System (UAS) strategies which includes developing a coordinated effort to maximize the efficiency and capabilities of unmanned systems across the federal government and research partners. Numerous intra- and inter-agency operational demonstrations and assessments have been made to verify and validated these strategies. This includes the introduction of the Targeted Autonomous Insitu Sensing and Rapid Response (TAISRR) with UAS concept of operations. The presentation will also discuss the requisite UAS capabilities and our experience in using them.

  19. Diversity and physiology of marine lignicolous fungi in Arctic waters: a preliminary account

    Directory of Open Access Journals (Sweden)

    Ka-Lai Pang

    2011-01-01

    Full Text Available Information on the diversity of marine fungi in polar environments is lacking, especially marine fungi colonizing wood. During visits to Tromsø and Longyearbyen, Norway, drift and trapped wood was collected to provide a preliminary account of lignicolous marine fungi in Arctic waters. Six marine fungi were recorded from 24 and 27 samples of wood from Tromsø and Longyearbyen, respectively. Among these, four marine fungi new to science were identified from wood collected at Longyearbyen. To shed light on the ecological role of this group of fungi in the Arctic, a physiological study of one of the collected fungi, Havispora longyearbyenensis, was conducted. H. longyearbyenensis grew at 4 °C, 10 °C, 15 °C and 20 °C in all salinities tested (0 0/00, 17 0/00, 34 0/00. However, growth was significantly reduced at 4 °C and 0 0/00 salinity. The optimal condition for growth of H. longyearbyenensis was at 20 °C in all salinities tested.

  20. Possible impact of decreasing Arctic pack ice on the higher trophic levels: Seabirds and marine mammals

    OpenAIRE

    Joiris, C.R.

    2012-01-01

    Three main aspects of the possible impacts of retreating pack ice and changing ice coverage in the European Arctic on the higher trophic levels are discussed in this chapter: 1. Seabirds are depending on their colonies on land during the breeding season; the main species, e.g. little auk Alle alle, feed in mixed Polar/ Arctic Water in order to bring back food (polar zooplankton) to their chicks on the nest. In case ice coverage is very low, distance between colony and feeding grounds might be...

  1. Simulated and observed trends in key variables of the Arctic marine carbon cycle

    Science.gov (United States)

    Goris, Nadine; Heinze, Christoph; Lauvset, Siv; Petrenko, Dmitry; Pozdnyakov, Dmitry; Schwinger, Jörg

    2013-04-01

    For the Arctic region, a thorough monitoring of the marine carbon cycle is important, as the general "polar amplification" of climate change also translates into the biogeochemical realm. As compared to the global ocean, the sink for human-produced CO2 is fairly small in the Arctic Ocean itself. Nevertheless, it is important to follow up this Arctic sink as a further control of the regional carbon budget and to record changes in the marine carbon cycle on the way towards a "blue Arctic". Since observations on the Arctic are rare, the EU FP7 MONARCH-A project tries to enable adequate descriptions of the status and evolution of the Arctic region Earth system components by generating time series of observation datasets and model hindcasts. In terms of the marine carbon cycle, this analysis focuses mainly on the key variables pCO2 and primary productivity. For oceanic pCO2, the comprehensive data-sets SOCAT and LDEO were combined, while measurements of atmospheric CO2 were collected from the GLOBALVIEW-CO2 data integration project. Monthly Primary Production fields were retrieved from the sensors MODIS and SeaWiFs. In order to get an overall picture of the behavior and trends of those key variables, in addition the physical-biogeochemical model MICOM-HAMOCC-M was employed. The investigation showed that both oceanic and atmospheric pCO2 are consistent variables which have a regular annual cycle and a similar behaviour all over the Arctic for both model and data. In contrast, primary production shows an irregular annual cycle in both range and form, varying over the Arctic. While a few well distributed measurement stations with continuous observations are sufficient to get a comprehensive picture for consistent variables like pCO2, it is relatively difficult and costly to get a comprehensive record of non-consistent variables. Since the provided data-set for primary production covers a relatively short time-scale, it was neither possible to confidently validate the model

  2. Influence of season, location, and feeding strategy on bioaccumulation of halogenated organic contaminants in Arctic marine zooplankton.

    Science.gov (United States)

    Hallanger, Ingeborg G; Ruus, Anders; Herzke, Dorte; Warner, Nicholas A; Evenset, Anita; Heimstad, Eldbjørg S; Gabrielsen, Geir W; Borgå, Katrine

    2011-01-01

    The influence of season, location, feeding strategy, and trophic position on concentration, compositional pattern, and bioaccumulation factors (BAFs) of halogenated organic contaminants (HOCs; polychlorinated biphenyls, chlorinated pesticides, and brominated flame retardants) was investigated within an Arctic zooplankton food web. Water (dissolved fraction) and seven Arctic marine pelagic zooplankton species (including herbivores, omnivores, and predators) were sampled in May, July, and October 2007 at two stations in Kongsfjorden, Svalbard, Norway. The HOC concentrations in both water and zooplankton generally decreased from May to October. The HOC concentrations and patterns among zooplankton species were explained by their feeding strategies, roughly categorized as herbivores, omnivores, and predators, and not stable isotope-derived trophic position. Field-derived BAFs varied greatly, with higher BAFs in May compared with July and October. Furthermore, BAFs differed among the species according to their feeding strategies. The relationship between BAFs from the different seasons and K(OW) (octanol:water partitioning coefficient) showed comparable intercepts and different slopes between May and October, with all relationships diverging from the assumed 1:1 relationship between BAF and K(OW). Differences in HOC concentrations and BAFs from herbivores to predators showed that biomagnification occurred in zooplankton. The results suggest that concentrations and patterns of HOCs in zooplankton species are influenced not only by equilibrium partitioning with water but also by feeding strategy. PMID:20853452

  3. Medicinal foods from marine animals: current status and prospects.

    Science.gov (United States)

    Kim, Se-Kwon; Pallela, Ramjee

    2012-01-01

    The lifestyle of human being is changing day by day toward the simplified and more convenient way of living. Human wellbeing is majorly dependent on the daily food habits that are in accordance with the habits of individual community and the surrounding environments. Although the food habits are simplified and fashioned according to the current lifestyle, many of the Asians are still showing much importance to the naturally derived and traditional foods. One such medicinally important natural source is the foods from marine organisms, which are an important growing notion for the development of marine nutraceuticals and functional foods. In this context, we have already brought the recent trends and applications of marine algal (macro and micro) foods in my previous volume. The current preliminary chapter of this book volume on marine animals and microbes describes about the prospects of various marine animals and their derived substances/materials as medicinal foods. In addition, this chapter encourages the new researchers as well as various health communities to implement the marine animal-based medicinal foods and their applications.

  4. Marine biodegradation of crude oil in temperate and Arctic water samples.

    Science.gov (United States)

    Kristensen, Mette; Johnsen, Anders R; Christensen, Jan H

    2015-12-30

    Despite increased interest in marine oil exploration in the Arctic, little is known about the fate of Arctic offshore oil pollution. Therefore, in the present study, we examine the oil degradation potential for an Arctic site (Disko Bay, Greenland) and discuss this in relation to a temperate site (North Sea, Denmark). Biodegradation was assessed following exposure to Oseberg Blend crude oil (100 mg L(-1)) in microcosms. Changes in oil hydrocarbon fingerprints of polycyclic aromatic hydrocarbons (PAHs), alkyl-substituted PAHs, dibenzothiophenes, n-alkanes and alkyltoluenes were measured by gas chromatography-mass spectrometry (GC-MS). In the Disko Bay sample, the degradation order was n-alkanes>alkyltoluenes (para->meta->ortho-isomers)>PAHs and dibenzothiophenes, whereas, the degradation order in the North Sea samples was PAHs and dibenzothiophenes>alkyltoluenes>n-alkanes. These differences in degradation patterns significantly affect the environmental risk of oil spills and emphasise the need to consider the specific environmental conditions when conducting risk assessments of Arctic oil pollution.

  5. Importance of Marine-Derived Nutrients Supplied by Planktivorous Seabirds to High Arctic Tundra Plant Communities

    Science.gov (United States)

    Zwolicki, Adrian; Zmudczyńska-Skarbek, Katarzyna; Richard, Pierre; Stempniewicz, Lech

    2016-01-01

    We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic) that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris) from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina). Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale. PMID:27149113

  6. Importance of Marine-Derived Nutrients Supplied by Planktivorous Seabirds to High Arctic Tundra Plant Communities.

    Directory of Open Access Journals (Sweden)

    Adrian Zwolicki

    Full Text Available We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina. Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale.

  7. Importance of Marine-Derived Nutrients Supplied by Planktivorous Seabirds to High Arctic Tundra Plant Communities.

    Science.gov (United States)

    Zwolicki, Adrian; Zmudczyńska-Skarbek, Katarzyna; Richard, Pierre; Stempniewicz, Lech

    2016-01-01

    We studied the relative importance of several environmental factors for tundra plant communities in five locations across Svalbard (High Arctic) that differed in geographical location, oceanographic and climatic influence, and soil characteristics. The amount of marine-derived nitrogen in the soil supplied by seabirds was locally the most important of the studied environmental factors influencing the tundra plant community. We found a strong positive correlation between δ15N isotopic values and total N content in the soil, confirming the fundamental role of marine-derived matter to the generally nutrient-poor Arctic tundra ecosystem. We also recorded a strong correlation between the δ15N values of soil and of the tissues of vascular plants and mosses, but not of lichens. The relationship between soil δ15N values and vascular plant cover was linear. In the case of mosses, the percentage ground cover reached maximum around a soil δ 15N value of 8‰, as did plant community diversity. This soil δ15N value clearly separated the occurrence of plants with low nitrogen tolerance (e.g. Salix polaris) from those predominating on high N content soils (e.g. Cerastium arcticum, Poa alpina). Large colonies of planktivorous little auks have a great influence on Arctic tundra vegetation, either through enhancing plant abundance or in shaping plant community composition at a local scale. PMID:27149113

  8. Zinc Isotope Ratios as Indicators of Diet and Trophic Level in Arctic Marine Mammals.

    Science.gov (United States)

    Jaouen, Klervia; Szpak, Paul; Richards, Michael P

    2016-01-01

    Carbon and nitrogen stable isotope ratios of bone collagen are an established method for dietary reconstruction, but this method is limited by the protein preservation. Zinc (Zn) is found in bioapatite and the isotopic compositions of this element constitute a very promising dietary indicator. The extent of fractionation of Zn isotopes in marine environments, however, remains unknown. We report here on the measurement of zinc, carbon and nitrogen isotopes in 47 marine mammals from the archaeological site of Arvik in the Canadian Arctic. We undertook this study to test and demonstrate the utility of Zn isotopes in recent mammal bone minerals as a dietary indicator by comparing them to other isotopic dietary tracers. We found a correlation between δ66Zn values and trophic level for most species, with the exception of walruses, which may be caused by their large seasonal movements. δ6Zn values can therefore be used as a dietary indicator in marine ecosystems for both modern and recent mammals.

  9. Food and soil-borne Penicillia in Arctic environments: Chemical diversity

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian

    Penicillia are very common inhabitants of cold environments, including arctic soil, plants, animals, and foods. We have investigated the mycobiota of Greenland inland ice and soil, and found a very unique and pronounced diversity among the Penicillia. Nearly all species were new to science....... The species found in inland ice were both of the soil-borne type, and Penicillia that grow and sporulate well at 25°C. The latter group of Penicillia have been found earlier in refrigerated foods, including P. nordicum, and in glacier ice and melting water from Svalbard (se Sonjak et al., this conference......). This “food-borne group” of arctic fungi also contained some new species, but not as many as in arctic soil. The chemical diversity of the Penicillium species was remarkably high and in most cases even larger than the chemical diversity of Penicillia in the tropics. Several new secondary metabolites were...

  10. Arctic cephalopod distributions and their associated predators

    OpenAIRE

    Gardiner, Kathleen; Terry A Dick

    2010-01-01

    Cephalopods are key species of the eastern Arctic marine food web, both as prey and predator. Their presence in the diets of Arctic fish, birds and mammals illustrates their trophic importance. There has been considerable research on cephalopods (primarily Gonatus fabricii) from the north Atlantic and the west side of Greenland, where they are considered a potential fishery and are taken as a by-catch. By contrast, data on the biogeography of Arctic cephalopods are still incomplete. This stud...

  11. The Arctic Ocean marine carbon cycle: evaluation of air-sea CO2 exchanges, ocean acidification impacts and potential feedbacks

    Directory of Open Access Journals (Sweden)

    J. T. Mathis

    2009-07-01

    Full Text Available At present, although seasonal sea-ice cover mitigates atmosphere-ocean gas exchange, the Arctic Ocean takes up carbon dioxide (CO2 on the order of −65 to −175 Tg C year−1, contributing 5–14% to the global balance of CO2 sinks and sources. Because of this, the Arctic Ocean is an important influence on the global carbon cycle, with the marine carbon cycle and atmosphere-ocean CO2 exchanges sensitive to Arctic Ocean and global climate change feedbacks. In the near-term, further sea-ice loss and increases in phytoplankton growth rates are expected to increase the uptake of CO2 by Arctic surface waters, although mitigated somewhat by surface warming in the Arctic. Thus, the capacity of the Arctic Ocean to uptake CO2 is expected to alter in response to environmental changes driven largely by climate. These changes are likely to continue to modify the physics, biogeochemistry, and ecology of the Arctic Ocean in ways that are not yet fully understood. In surface waters, sea-ice melt, river runoff, cooling and uptake of CO2 through air-sea gas exchange combine to decrease the calcium carbonate (CaCO3 mineral saturation states (Ω of seawater that is counteracted by seasonal phytoplankton primary production (PP. Biological processes drive divergent trajectories for Ω in surface and subsurface waters of Arctic shelves with subsurface water experiencing undersaturation with respect to aragonite and calcite. Thus, in response to increased sea-ice loss, warming and enhanced phytoplankton PP, the benthic ecosystem of the Arctic shelves are expected to be negatively impacted by the biological amplification of ocean acidification. This in turn reduces the ability of many species to produce CaCO3 shells or tests with profound implications for Arctic marine ecosystems.

  12. Influence of chemical and biological factors on trophic transfer of persistent organic pollutants in the northwater polynya marine food web.

    Science.gov (United States)

    Fisk, A T; Hobson, K A; Norstrom, R J

    2001-02-15

    Persistent organic pollutants (POPs) and stable isotopes of nitrogen (delta 15N) were measured in zooplankton (6 species), a benthic invertebrate (Anonyx nugax), Arctic cod (Boreogadus saida), seabirds (6 species), and ringed seals (Phoca hispida) collected in 1998 in the Northwater Polynya to examine effects of biological and chemical factors on trophic transfer of POPs in an Arctic marine food web. Strong positive relationships were found between recalcitrant POP concentrations (lipid corrected) and trophic level based on stable isotopes of nitrogen, providing clear evidence of POP biomagnification in Arctic marine food webs. Food web magnification factors (FWMFs), derived from the slope of the POP--trophic level relationship, provided an overall magnification factor for the food web but over and underestimated biomagnification factors (BMFs) based on predator--prey concentrations in poikilotherms (fish) and homeotherms (seabirds and mammals), respectively. Greater biomagnification in homeotherms was attributed to their greater energy requirement and subsequent feeding rates. Within the homeotherms, seabirds had greater BMFs than ringed seals, consistent with greater energy demands in birds. Scavenging from marine mammal carcasses and accumulation in more contaminated winter habitats were considered important variables in seabird BMFs. Metabolic differences between species resulted in lower than expected BMFs, which would not be recognized in whole food web trophic level--POP relationships. The use of sigma POP groups, such as sigma PCB, is problematic because FWMFs and BMFs varied considerably between individual POPs. FWMFs of recalcitrant POPs had a strong positive relationship with log octanol--water partition coefficient (Kow). Results of this study show the utility of using delta 15N to characterize trophic level and trophic transfer of POPs but highlight the effects of species and chemical differences on trophic transfer of POPs that can be overlooked when

  13. Responses in Arctic marine carbon cycle processes: conceptual scenarios and implications for ecosystem function

    Directory of Open Access Journals (Sweden)

    Helen S. Findlay

    2015-04-01

    Full Text Available The Arctic Ocean is one of the fastest changing oceans, plays an important role in global carbon cycling and yet is a particularly challenging ocean to study. Hence, observations tend to be relatively sparse in both space and time. How the Arctic functions, geophysically, but also ecologically, can have significant consequences for the internal cycling of carbon, and subsequently influence carbon export, atmospheric CO2 uptake and food chain productivity. Here we assess the major carbon pools and associated processes, specifically summarizing the current knowledge of each of these processes in terms of data availability and ranges of rates and values for four geophysical Arctic Ocean domains originally described by Carmack & Wassmann (2006: inflow shelves, which are Pacific-influenced and Atlantic-influenced; interior, river-influenced shelves; and central basins. We attempt to bring together knowledge of the carbon cycle with the ecosystem within each of these different geophysical settings, in order to provide specialist information in a holistic context. We assess the current state of models and how they can be improved and/or used to provide assessments of the current and future functioning when observational data are limited or sparse. In doing so, we highlight potential links in the physical oceanographic regime, primary production and the flow of carbon within the ecosystem that will change in the future. Finally, we are able to highlight priority areas for research, taking a holistic pan-Arctic approach.

  14. Low Density of Top Predators (Seabirds and Marine Mammals in the High Arctic Pack Ice

    Directory of Open Access Journals (Sweden)

    Claude R. Joiris

    2016-01-01

    Full Text Available The at-sea distribution of top predators, seabirds and marine mammals, was determined in the high Arctic pack ice on board the icebreaker RV Polarstern in July to September 2014. In total, 1,620 transect counts were realised, lasting 30 min each. The five most numerous seabird species represented 74% of the total of 15,150 individuals registered: kittiwake Rissa tridactyla, fulmar Fulmarus glacialis, puffin Fratercula arctica, Ross’s gull Rhodostethia rosea, and little auk Alle alle. Eight cetacean species were tallied for a total of 330 individuals, mainly white-beaked dolphin Lagenorhynchus albirostris and fin whale Balaenoptera physalus. Five pinniped species were represented by a total of 55 individuals and the polar bear Ursus maritimus was represented by 12 individuals. Four main geographical zones were identified: from Tromsø to the outer marginal ice zone (OMIZ, the Arctic pack ice (close pack ice, CPI, the end of Lomonosov Ridge off Siberia, and the route off Siberia and northern Norway. Important differences were detected between zones, both in species composition and in individual abundance. Low numbers of species and high proportion of individuals for some of them can be considered to reflect very low biodiversity. Numbers encountered in zones 2 to 4 were very low in comparison with other European Arctic seas. The observed differences showed strong patterns.

  15. Extending Hydrologic Information Systems to accommodate Arctic marine observations data

    Science.gov (United States)

    Hersh, Eric S.; Maidment, David R.

    2014-04-01

    The Chukchi Sea Offshore Monitoring in Drilling Area - Chemical and Benthos (COMIDA CAB) project characterizes the biota and chemistry of the continental shelf ecosystem of a region of the Chukchi Sea to form a baseline survey of environmental conditions before drilling for oil commences. This paper describes the COMIDA CAB project data and processing methods, which provide a novel approach to data tracking and archiving from marine sampling cruises. This approach features an adaptation of the Consortium of Universities for the Advancement of Hydrologic Science. Observations Data Model for application with physical, chemical, and biological oceanographic data - a new extension of the CUAHSI Hydrologic Information System - thus bringing hydroinformatics into the oceanographic realm. Environmental sampling has been carried out by five separate scientific teams who characterize particular classes of physical, chemical and biological variables, and who each have their own methods of processing samples in their laboratories following the two sampling cruises made to the Chukchi Sea in the summers of 2009 and 2010. The results of their observations and analyses are stored in data files, mostly in Excel format, whose structure is defined differently by each scientific team. In all, the 2009 and 2010 COMIDA CAB field efforts yielded a database of 510,405 data values. Of these, 474,129 were derived from continuous in-situ data sonde profiles and 36,276 were derived from non-sonde extracted samples of the sediment, epibenthos, and water column. These data values represent 301 variables measured at 65 sites and originated from 26 different source files. The biological observations represented 519 distinct taxa. The data from these files are transformed and synthesized into a comprehensive project database in which a set of standardized descriptors of each observed data value are specified and each data value is linked to the data file from which it was created to establish a

  16. Comparison between summertime and wintertime Arctic Ocean primary marine aerosol properties

    Directory of Open Access Journals (Sweden)

    J. Zábori

    2013-05-01

    Full Text Available Primary marine aerosols (PMAs are an important source of cloud condensation nuclei, and one of the key elements of the remote marine radiative budget. Changes occurring in the rapidly warming Arctic, most importantly the decreasing sea ice extent, will alter PMA production and hence the Arctic climate through a set of feedback processes. In light of this, laboratory experiments with Arctic Ocean water during both Arctic winter and summer were conducted and focused on PMA emissions as a function of season and water properties. Total particle number concentrations and particle number size distributions were used to characterize the PMA population. A comprehensive data set from the Arctic summer and winter showed a decrease in PMA concentrations for the covered water temperature (Tw range between −1°C and 15°C. A sharp decrease in PMA emissions for a Tw increase from −1°C to 4°C was followed by a lower rate of change in PMA emissions for Tw up to about 6°C. Near constant number concentrations for water temperatures between 6°C to 10°C and higher were recorded. Even though the total particle number concentration changes for overlapping Tw ranges were consistent between the summer and winter measurements, the distribution of particle number concentrations among the different sizes varied between the seasons. Median particle number concentrations for a dry diameter (DpDp > 0.125μm, the particle number concentrations during winter were mostly higher than in summer (up to 50%. The normalized particle number size distribution as a function of water temperature was examined for both winter and summer measurements. An increase in Tw from −1°C to 10°C during winter measurements showed a decrease in the peak of relative particle number concentration at about a Dp of 0.180μm, while an increase was observed for particles with Dp > 1μm. Summer measurements exhibited a relative shift to smaller particle sizes for an increase of Tw in the range

  17. Sampling and analysis in the Arctic marine benthic environment. Vol. 2. Guide to practice

    Energy Technology Data Exchange (ETDEWEB)

    1985-03-01

    There is an increasing requirement for environmental information on Arctic marine sediments because of natural resource development, particularly offshore hydrocarbon exploration and associated proposed transport mechanisms. At the same time, it is recognized that methods that have been used for collection, analysis and data reporting need improvement if the data are to have long term value. This is the second part of a study to produce a guide for managers and planners involved in the collection and analysis of environmental data from marine sediments in Arctic regions. The first phase of this study (Volume 1) reviewed existing methods and was intended to serve as a background document to the present report. The format is designed to outline in a step-by-step manner the factors to be considered and offers suggestions as to possible methods to achieve various results. This guide includes sampling strategy and means of quality control, sampling and subsampling methods for chemical analysis, sampling methods for benthos, means of sample preservation and storage, sampling logistics (transport, positioning and sampling from ice), methods of sample analysis for metals, organics, grain size, Pb-210 dating, methods of laboratory quality assurance and methods for the analysis of benthic data. 319 refs., 14 figs., 44 tabs.

  18. Problems of toxicants in marine food products. 1. Marine biotoxins.

    Science.gov (United States)

    Bagnis, R; Berglund, F; Elias, P S; van Esch, G J; Halstead, B W; Kojima, K

    1970-01-01

    The expansion of marine fisheries into tropical waters, which is now occurring, will increase the risks of widespread poisonings because of the abundance of biotoxins in warm-water organisms. However, toxic marine organisms are not only a health hazard but also a possible source of new pharmaceutical products.A classification of marine intoxicants is given in this paper with special reference to the oral biotoxins which will be of primary concern in the expansion of warm-water fisheries. The biotoxins are both invertebrate (e.g., molluscs, arthropods) and vertebrate (mostly fishes) in origin. Biotoxications of vertebrate origin may be caused by the muscles, the gonads or the blood of certain fishes or by special poison glands not equipped with traumagenic devices. (Venomous fishes, having poison glands and traumagenic spines, etc., are of no direct concern as oral intoxicants.)The ichthyosarcotoxic fishes, in which the flesh is poisonous, appear to constitute the most significant health hazard. A list of fishes reported as causing ciguatera poisoning (one of the most serious and widespread forms of ichthyosarcotoxism) is included in this paper.

  19. Arctic Small Rodents Have Diverse Diets and Flexible Food Selection

    OpenAIRE

    Soininen, Eeva M.; Ravolainen, Virve T.; Kari Anne Bråthen; YOCCOZ, Nigel G.; Ludovic Gielly; Ims, Rolf A.

    2013-01-01

    The ecology of small rodent food selection is poorly understood, as mammalian herbivore food selection theory has mainly been developed by studying ungulates. Especially, the effect of food availability on food selection in natural habitats where a range of food items are available is unknown. We studied diets and selectivity of grey-sided voles (Myodes rufocanus) and tundra voles (Microtus oeconomus), key herbivores in European tundra ecosystems, using DNA metabarcoding, a novel method enabl...

  20. Freshwater and its role in the Arctic Marine System: Sources, disposition, storage, export, and physical and biogeochemical consequences in the Arctic and global oceans

    Science.gov (United States)

    Carmack, E. C.; Yamamoto-Kawai, M.; Haine, T. W. N.; Bacon, S.; Bluhm, B. A.; Lique, C.; Melling, H.; Polyakov, I. V.; Straneo, F.; Timmermans, M.-L.; Williams, W. J.

    2016-03-01

    The Arctic Ocean is a fundamental node in the global hydrological cycle and the ocean's thermohaline circulation. We here assess the system's key functions and processes: (1) the delivery of fresh and low-salinity waters to the Arctic Ocean by river inflow, net precipitation, distillation during the freeze/thaw cycle, and Pacific Ocean inflows; (2) the disposition (e.g., sources, pathways, and storage) of freshwater components within the Arctic Ocean; and (3) the release and export of freshwater components into the bordering convective domains of the North Atlantic. We then examine physical, chemical, or biological processes which are influenced or constrained by the local quantities and geochemical qualities of freshwater; these include stratification and vertical mixing, ocean heat flux, nutrient supply, primary production, ocean acidification, and biogeochemical cycling. Internal to the Arctic the joint effects of sea ice decline and hydrological cycle intensification have strengthened coupling between the ocean and the atmosphere (e.g., wind and ice drift stresses, solar radiation, and heat and moisture exchange), the bordering drainage basins (e.g., river discharge, sediment transport, and erosion), and terrestrial ecosystems (e.g., Arctic greening, dissolved and particulate carbon loading, and altered phenology of biotic components). External to the Arctic freshwater export acts as both a constraint to and a necessary ingredient for deep convection in the bordering subarctic gyres and thus affects the global thermohaline circulation. Geochemical fingerprints attained within the Arctic Ocean are likewise exported into the neighboring subarctic systems and beyond. Finally, we discuss observed and modeled functions and changes in this system on seasonal, annual, and decadal time scales and discuss mechanisms that link the marine system to atmospheric, terrestrial, and cryospheric systems.

  1. Arctic Diatoms

    DEFF Research Database (Denmark)

    Tammilehto, Anna

    shellfish poisoning (ASP). This thesis showed that three most abundant mesozooplankton species (Calanus finmarchicus, C. glacialis and C. hyperboreus and copepodite stages C3 and C4) in the study area (Disko Bay, western Greenland) feed upon toxic P. seriata and retain the toxin, and may therefore act...... as vectors for DA to higher levels in the arctic marine food web, posing a possible risk also to humans. DA production in P. seriata was, for the first time, found to be induced by chemical cues from C. finmarchicus, C. hyperboreus and copepodite stages C3 and C4, suggesting that DA may be related to defense...

  2. Late Paleocene Arctic Ocean shallow-marine temperatures from mollusc stable isotopes

    Science.gov (United States)

    Bice, Karen L.; Arthur, Michael A.; Marincovich, Louie, Jr.

    1996-01-01

    Late Paleocene high-latitude (80°N) Arctic Ocean shallow-marine temperatures are estimated from molluscan δ18O time series. Sampling of individual growth increments of two specimens of the bivalve Camptochlamys alaskensis provides a high-resolution record of shell stable isotope composition. The heavy carbon isotopic values of the specimens support a late Paleocene age for the youngest marine beds of the Prince Creek Formation exposed near Ocean Point, Alaska. The oxygen isotopic composition of regional freshwater runoff is estimated from the mean δ18O value of two freshwater bivalves collected from approximately coeval fluviatile beds. Over a 30 – 34‰ range of salinity, values assumed to represent the tolerance of C. alaskensis, the mean annual shallow-marine temperature recorded by these individuals is between 11° and 22°C. These values could represent maximum estimates of the mean annual temperature because of a possible warm-month bias imposed on the average δ18O value by slowing or cessation of growth in winter months. The amplitude of the molluscan δ18O time series probably records most of the seasonality in shallow-marine temperature. The annual temperature range indicated is approximately 6°C, suggesting very moderate high-latitude marine temperature seasonality during the late Paleocene. On the basis of analogy with modern Chlamys species, C. alaskensis probably inhabited water depths of 30–50 m. The seasonal temperature range derived from δ18O is therefore likely to be damped relative to the full range of annual sea surface temperatures. High-resolution sampling of molluscan shell material across inferred growth bands represents an important proxy record of seasonality of marine and freshwater conditions applicable at any latitude. If applied to other regions and time periods, the approach used here would contribute substantially to the paleoclimate record of seasonality.

  3. Latitudinal variation in ecological opportunity and intraspecific competition indicates differences in niche variability and diet specialization of Arctic marine predators.

    Science.gov (United States)

    Yurkowski, David J; Ferguson, Steve; Choy, Emily S; Loseto, Lisa L; Brown, Tanya M; Muir, Derek C G; Semeniuk, Christina A D; Fisk, Aaron T

    2016-03-01

    Individual specialization (IS), where individuals within populations irrespective of age, sex, and body size are either specialized or generalized in terms of resource use, has implications on ecological niches and food web structure. Niche size and degree of IS of near-top trophic-level marine predators have been little studied in polar regions or with latitude. We quantified the large-scale latitudinal variation of population- and individual-level niche size and IS in ringed seals (Pusa hispida) and beluga whales (Delphinapterus leucas) using stable carbon and nitrogen isotope analysis on 379 paired ringed seal liver and muscle samples and 124 paired beluga skin and muscle samples from eight locations ranging from the low to high Arctic. We characterized both within- and between-individual variation in predator niche size at each location as well as accounting for spatial differences in the isotopic ranges of potential prey. Total isotopic niche width (TINW) for populations of ringed seals and beluga decreased with increasing latitude. Higher TINW values were associated with greater ecological opportunity (i.e., prey diversity) in the prey fish community which mainly consists of Capelin (Mallotus villosus) and Sand lance (Ammodytes sp.) at lower latitudes and Arctic cod (Boreogadus saida) at high latitudes. In beluga, their dietary consistency between tissues also known as the within-individual component (WIC) increased in a near 1:1 ratio with TINW (slope = 0.84), suggesting dietary generalization, whereas the slope (0.18) of WIC relative to TINW in ringed seals indicated a high degree of individual specialization in ringed seal populations with higher TINWs. Our findings highlight the differences in TINW and level of IS for ringed seals and beluga relative to latitude as a likely response to large-scale spatial variation in ecological opportunity, suggesting species-specific variation in dietary plasticity to spatial differences in prey resources and

  4. The Arctic Ocean marine carbon cycle: evaluation of air-sea CO2 exchanges, ocean acidification impacts and potential feedbacks

    Directory of Open Access Journals (Sweden)

    N. R. Bates

    2009-11-01

    Full Text Available At present, although seasonal sea-ice cover mitigates atmosphere-ocean gas exchange, the Arctic Ocean takes up carbon dioxide (CO2 on the order of −66 to −199 Tg C year−1 (1012 g C, contributing 5–14% to the global balance of CO2 sinks and sources. Because of this, the Arctic Ocean has an important influence on the global carbon cycle, with the marine carbon cycle and atmosphere-ocean CO2 exchanges sensitive to Arctic Ocean and global climate change feedbacks. In the near-term, further sea-ice loss and increases in phytoplankton growth rates are expected to increase the uptake of CO2 by Arctic Ocean surface waters, although mitigated somewhat by surface warming in the Arctic. Thus, the capacity of the Arctic Ocean to uptake CO2 is expected to alter in response to environmental changes driven largely by climate. These changes are likely to continue to modify the physics, biogeochemistry, and ecology of the Arctic Ocean in ways that are not yet fully understood. In surface waters, sea-ice melt, river runoff, cooling and uptake of CO2 through air-sea gas exchange combine to decrease the calcium carbonate (CaCO3 mineral saturation states (Ω of seawater while seasonal phytoplankton primary production (PP mitigates this effect. Biological amplification of ocean acidification effects in subsurface waters, due to the remineralization of organic matter, is likely to reduce the ability of many species to produce CaCO3 shells or tests with profound implications for Arctic marine ecosystems

  5. Community structure, cellular rRNA content, and activity of sulfate-reducing bacteria in marine Arctic sediments

    DEFF Research Database (Denmark)

    Ravenschlag, K.; Sahm, K.; Knoblauch, C.;

    2000-01-01

    The community structure of sulfate-reducing bacteria (SRB) of a marine Arctic sediment (Smeerenburg-fjorden, Svalbard) a-as characterized by both fluorescence in situ hybridization (FISH) and rRNA slot blot hybridization by using group- and genus-specific 16S rRNA-targeted oligonucleotide probes...

  6. Zinc Isotope Ratios as Indicators of Diet and Trophic Level in Arctic Marine Mammals.

    Directory of Open Access Journals (Sweden)

    Klervia Jaouen

    Full Text Available Carbon and nitrogen stable isotope ratios of bone collagen are an established method for dietary reconstruction, but this method is limited by the protein preservation. Zinc (Zn is found in bioapatite and the isotopic compositions of this element constitute a very promising dietary indicator. The extent of fractionation of Zn isotopes in marine environments, however, remains unknown. We report here on the measurement of zinc, carbon and nitrogen isotopes in 47 marine mammals from the archaeological site of Arvik in the Canadian Arctic. We undertook this study to test and demonstrate the utility of Zn isotopes in recent mammal bone minerals as a dietary indicator by comparing them to other isotopic dietary tracers. We found a correlation between δ66Zn values and trophic level for most species, with the exception of walruses, which may be caused by their large seasonal movements. δ6Zn values can therefore be used as a dietary indicator in marine ecosystems for both modern and recent mammals.

  7. Zinc Isotope Ratios as Indicators of Diet and Trophic Level in Arctic Marine Mammals.

    Science.gov (United States)

    Jaouen, Klervia; Szpak, Paul; Richards, Michael P

    2016-01-01

    Carbon and nitrogen stable isotope ratios of bone collagen are an established method for dietary reconstruction, but this method is limited by the protein preservation. Zinc (Zn) is found in bioapatite and the isotopic compositions of this element constitute a very promising dietary indicator. The extent of fractionation of Zn isotopes in marine environments, however, remains unknown. We report here on the measurement of zinc, carbon and nitrogen isotopes in 47 marine mammals from the archaeological site of Arvik in the Canadian Arctic. We undertook this study to test and demonstrate the utility of Zn isotopes in recent mammal bone minerals as a dietary indicator by comparing them to other isotopic dietary tracers. We found a correlation between δ66Zn values and trophic level for most species, with the exception of walruses, which may be caused by their large seasonal movements. δ6Zn values can therefore be used as a dietary indicator in marine ecosystems for both modern and recent mammals. PMID:27010907

  8. Proceedings of the 29. Arctic and Marine Oilspill Program (AMOP) Technical Seminar

    International Nuclear Information System (INIS)

    This conference was a venue to exchange information on leading-edge technologies used in marine oil spill response operations. The different sessions at this conference were entitled: (1) physical and chemical properties and behaviour of spilled oil, (2) containment and recovery, (3) activity updates and contingency planning, (4) phytoremediation of inorganic and radionuclides, (5) biosolutions to site remediation, restoration and rehabilitation, (6) phytoremediation of petroleum hydrocarbons, (7) oil spill treating agents, (8) spill modelling, (9) detection, tracking and remote sensing, (10) special session on hurricanes, and (11) recent spill experiences. In addition to a poster session with papers, the conference also featured a technical seminar on chemical spills with a special session on counter-terrorism. Many presentations addressed the issue of optimizing response functions in harsh Arctic marine waters as well as strategy development for marine oil spill response and shoreline assessment. Several studies focused on oil-in-water interactions to find new mechanical, chemical and biological treatments for oil spills. All 65 presentations were indexed separately for inclusion in this database. refs., tabs., figs

  9. Trophic relationships in an Arctic food web and implications for trace metal transfer

    International Nuclear Information System (INIS)

    Tissues of subsistence-harvested Arctic mammals were analyzed for silver (Ag), cadmium (Cd), and total mercury (THg). Muscle (or total body homogenates of potential fish and invertebrate prey) was analyzed for stable carbon (δ 13C) and nitrogen (δ 15N) isotopes to establish trophic interactions within the Arctic food chain. Food web magnification factors (FWMFs) and biomagnification factors for selected predator-prey scenarios (BMFs) were calculated to describe pathways of heavy metals in the Alaskan Arctic. FWMFs in this study indicate that magnification of selected heavy metals in the Arctic food web is not significant. Biomagnification of Cd occurs mainly in kidneys; calculated BMFs are higher for hepatic THg than renal THg for all predator-prey scenarios with the exception of polar bears (Ursus maritimus). In bears, the accumulation of renal THg is approximately 6 times higher than in liver. Magnification of hepatic Ag is minimal for all selected predator-prey scenarios. Though polar bears occupy a higher trophic level than belugas (Delphinapterus leucas), based on δ 15N, the metal concentrations are either not statistically different between the two species or lower for bears. Similarly, concentrations of renal and hepatic Cd are significantly lower or not statistically different in polar bears compared to ringed (Phoca hispida) and bearded seals (Erignathus barbatus), their primary prey. THg, on the other hand, increased significantly from seal to polar bear tissues. Mean δ 15N was lowest in muscle of Arctic fox (Alopex lagopus) and foxes also show the lowest levels of Hg, Cd and Ag in liver and kidney compared to the other species analyzed. These values are in good agreement with a diet dominated by terrestrial prey. Metal deposition in animal tissues is strongly dependent on biological factors such as diet, age, sex, body condition and health, and caution should be taken when interpreting magnification of dynamic and actively regulated trace metals

  10. SOLID RADIOACTIVE WASTE STORAGE TECHNOLOGIES: PERFORMANCE OF A POLYMER SEALANT COATING IN AN ARCTIC MARINE ENVIRONMENT

    Energy Technology Data Exchange (ETDEWEB)

    COWGILL,M.G.; MOSKOWITZ,P.D.; CHERNAENKO,L.M.; NAZARIAN,A.; GRIFFITH,A.; DIASHEV,A.; ENGOY,T.

    2000-06-14

    This first project, under the auspices of the Arctic Military Environmental Cooperation (AMEC) forum, Project 1.4-1 Solid Radioactive Waste Storage Technologies, successfully demonstrated the feasibility of using a polymer-based coating to seal concrete and steel surfaces from permanent radioactive contamination in an Arctic marine environment. A mobile, self-sufficient spraying device, was developed to specifications provided by the Russian Ministry of Defence Northern Navy and was deployed at the RTP Atomflot site, Murmansk, Russia. Demonstration coatings of Polibrid 705 were applied to concrete surfaces exposed to conditions ranging from indoor pedestrian usage to heavy vehicle passage and container handling in a loading bay. A large steel container was also coated with the polymer, filled with solid radwaste, sealed, and left out of doors and exposed to the full 12 month Arctic weather cycle. The field tests were accompanied by a series of laboratory qualification tests carried out at the research laboratory of ICC Nuclide in St. Petersburg. During the 12-month field tests, the sealant coating showed little sign of degradation except for a few chips and gouge marks on the loading bay surface that were readily repaired. Contamination resulting from radwaste handling was easily removed and the surface was not degraded by contact with the decontamination agents. In the laboratory testing, Polibrid 705 met all the Russian qualification requirements with the exception of flammability. In this last instance, it was decided to restrict application of the coating to land-based facilities. The Russian technical experts from the Ministry of Defence quickly familiarized themselves with the equipment and were able to identify several areas of potential improvement as deployment of the equipment progressed. The prime among these was the desirability of extending the range of the equipment through enlarged gasoline tanks (to permit extended operational times) and longer

  11. Performance of a polymer sealant coating in an arctic marine environment

    International Nuclear Information System (INIS)

    The feasibility of using a polymer-based coating, Polibrid 705, to seal concrete and steel surfaces from permanent radioactive contamination in an Arctic marine environment has been successfully demonstrated using a combination of field and laboratory testing. A mobile, self-sufficient spraying device was developed to specifications provided by the Russian Northern Navy and deployed at the RTP Atomflot site, Murmansk, Russia. Demonstration coatings were applied to concrete surfaces exposed to conditions ranging from indoor pedestrian usage to heavy vehicle passage and container handling in a loading dock. A large steel container was also coated with the polymer, filled with solid radwaste, sealed, and left out of doors, exposed to the full annual Arctic weather cycle. The 12 months of field testing gave rise to little degradation of the sealant coating, except for a few chips and gouge marks on the loading bay surface that were readily repaired. Contamination resulting from radwaste handling was easily removed and the surface was not degraded by contact with the decontamination agents. The field tests were accompanied by a series of laboratory qualification tests carried out at a research laboratory in St. Petersburg. The laboratory tests examined a variety of properties, including bond strength between the coating and the substrate, thermal cycling resistance, wear resistance, flammability, and ease of decontamination. The Polibrid 705 coating met all the Russian Navy qualification requirements with the exception of flammability. In this last instance, it was decided to restrict application of the coating to land-based facilities

  12. Organic carbon degradation in arctic marine sediments, Svalbard: A comparison of initial and terminal steps

    DEFF Research Database (Denmark)

    Arnosti, C.; Jørgensen, BB

    2006-01-01

    carbohydrate concentrations were comparable to those measured in more temperate sediments, and likely comprise a considerable fraction of porewater dissolved organic carbon. A comparison of dissolved carbohydrate inventories with hydrolysis and sulfate reduction rates suggests that the turnover of carbon......Degradation of marine organic matter under anoxic conditions involves microbial communities working in concert to remineralize complex substrates to CO2. In order to investigate the coupling between the initial and terminal steps of this sequence in permanently cold sediments, rates of...... extracellular enzymatic hydrolysis and sulfate reduction were measured in parallel cores collected from 5 fjords on the west and northwest coast of Svalbard, in the high Arctic. Inventories of total dissolved carbohydrates were also measured in order to evaluate their potential role in carbon turnover...

  13. Changing Arctic ecosystems--research to understand and project changes in marine and terrestrial ecosystems of the Arctic

    Science.gov (United States)

    Geiselman, Joy; DeGange, Anthony R.; Oakley, Karen; Derksen, Dirk; Whalen, Mary

    2012-01-01

    Ecosystems and their wildlife communities are not static; they change and evolve over time due to numerous intrinsic and extrinsic factors. A period of rapid change is occurring in the Arctic for which our current understanding of potential ecosystem and wildlife responses is limited. Changes to the physical environment include warming temperatures, diminishing sea ice, increasing coastal erosion, deteriorating permafrost, and changing water regimes. These changes influence biological communities and the ways in which human communities interact with them. Through the new initiative Changing Arctic Ecosystems (CAE) the U.S. Geological Survey (USGS) strives to (1) understand the potential suite of wildlife population responses to these physical changes to inform key resource management decisions such as those related to the Endangered Species Act, and (2) provide unique insights into how Arctic ecosystems are responding under new stressors. Our studies examine how and why changes in the ice-dominated ecosystems of the Arctic are affecting wildlife and will provide a better foundation for understanding the degree and manner in which wildlife species respond and adapt to rapid environmental change. Changes to Arctic ecosystems will be felt broadly because the Arctic is a production zone for hundreds of species that migrate south for the winter. The CAE initiative includes three major research themes that span Arctic ice-dominated ecosystems and that are structured to identify and understand the linkages between physical processes, ecosystems, and wildlife populations. The USGS is applying knowledge-based modeling structures such as Bayesian Networks to integrate the work.

  14. Indicators of food and water security in an Arctic Health context – results from an international workshop discussion

    Directory of Open Access Journals (Sweden)

    Lena Maria Nilsson

    2013-08-01

    Full Text Available In August 2012, a literature search with the aim of describing indicators on food and water security in an Arctic health context was initialized in collaboration between the Arctic Human Health Expert Group, SDWG/AHHEG and the AMAP (Arctic Monitoring and Assessment Programme within the Arctic Council Human Health Assessment Group, AMAP/HHAG. In December 2012, workshop discussions were performed with representatives from both of these organizations, including 7 Arctic countries. The aim of this article is to describe the workshop discussions and the rational for the 12 indicators selected and the 9 rejected and to discuss the potential feasibility of these. Advantages and disadvantages of candidate indicators were listed. Informative value and costs for collecting were estimated separately on a 3-level scale: low, medium and high. Based on these reviews, the final selection of promoted and rejected indicators was performed and summarized in tables. Among 10 suggested indicators of food security, 6 were promoted: healthy weight, traditional food proportion in diet, monetary food costs, non-monetary food accessibility, food-borne diseases and food-related contaminants. Four were rejected: per-person dietary energy supply, food security modules, self-estimated food safety and healthy eating. Among 10 suggested indicators of water security, 6 were promoted: per-capita renewable water, accessibility of running water, waterborne diseases, drinking-water-related contaminants, authorized water quality assurance and water safety plans. Four were rejected: water consumption, types of water sources, periodic water shortages and household water costs.

  15. Summertime aerosol chemical components in the marine boundary layer of the Arctic Ocean

    Science.gov (United States)

    Xie, Zhouqing; Sun, Liguang; Blum, Joel D.; Huang, Yuying; He, Wei

    2006-05-01

    Samples of aerosols from the marine boundary layer of the Arctic Ocean were collected aboard the R/V Xuelong during summer on the Second Chinese Arctic Research Expedition (July-September 2003). Synchrotron radiation X-ray fluorescence (SR-XRF) was used to determine chemical compositions of aerosol particles. Multivariate analysis of the SR-XRF data resolved a number of components (factors), which, on the basis of their chemical compositions and from their affiliation with specific meteorological flow patterns, were assigned physical meanings. Five factors explaining 94.7% of the total variance were identified. Ship emissions accounted for 35.3% of the variance (factor 1 (F1)) and are loaded significantly with S, Fe, V, and Ni. The total Fe emitted from ships globally was estimated at 8.60 × 106 kg yr-1. Heavy-metal-rich factors included 34.0% of the variance (F2 and F3) and were interpreted to be pollution carried into the Arctic Ocean by long-range transport. Anthropogenic contributions from industrial regions to the Arctic Ocean during the summer vary and depend on the source locations. Air mass backward trajectories indicate that the metals including Hg, Pb, Cu, and Zn come mainly from northern Russia. The third source controlling the chemical compositions of aerosols was sea salt (F4, 12.8%). The role of sea salt decreased from the open sea to areas near pack ice. On the basis of the factor scores of aerosol samples, we infer that chlorine volatilization from sea salt may occur, enhanced by nitrogen and sulfur contamination emitted from ships. Because the global inventories of nitrogen and sulfur for ship exhausts are large, and halogens could have important consequences in possible tropospheric ozone destruction, the role of ships in influencing halogen depression in sea salt should be further investigated. Finally, we also identified a crustal factor (F5, 12.6%) and suggest that crustal elements (e.g., Ca) contaminating sea ice may become reinjected into

  16. Comparison between summertime and wintertime Arctic Ocean primary marine aerosol properties

    Directory of Open Access Journals (Sweden)

    J. Zábori

    2012-12-01

    Full Text Available Primary marine aerosols (PMA are an important source of cloud condensation nuclei, and one of the key elements of the remote marine radiative budget. Changes occurring in the rapidly warming Arctic, most importantly the decreasing sea ice extent will alter PMA production and hence the Arctic climate through a set of feedback processes. In light of this, laboratory experiments with Arctic Ocean water during both Arctic winter and summer were conducted and focused on PMA emissions as a function of season and water properties. Total particle number concentrations and particle number size distributions were used to characterize the PMA population. A comprehensive data set from the Arctic summer and winter showed a decrease in PMA concentrations for the covered water temperature (Tw range between −1 °C and 15 °C. A sharp decrease in PMA emissions for a Tw increase from −1 °C to 4 °C was followed by a lower rate of change in PMA emissions for Tw up to about 6 °C. Near constant number concentrations for water temperatures between 6 °C to 10 °C and higher were recorded. Even though the total particle number concentrations changes for overlapping Tw ranges were consistent between the summer and winter measurements, the distribution of particle number concentrations among the different sizes varied between the seasons. Median particle number concentrations for Dp < 0.125 μm measured during winter conditions were similar (deviation of up to 3%, or lower (up to 70% than the ones measured during summer conditions (for the same water temperature range. For Dp > 0.125 μm, the particle number concentrations during winter were mostly higher than in summer (up to 50%. The normalized particle number size distribution as a function of water temperature was examined for both winter and summer measurements. An increase in Tw from

  17. Factors affecting biotic mercury concentrations and biomagnification through lake food webs in the Canadian high Arctic

    International Nuclear Information System (INIS)

    In temperate regions of Canada, mercury (Hg) concentrations in biota and the magnitude of Hg biomagnification through food webs vary between neighboring lakes and are related to water chemistry variables and physical lake features. However, few studies have examined factors affecting the variable Hg concentrations in landlocked Arctic char (Salvelinus alpinus) or the biomagnification of Hg through their food webs. We estimated the food web structure of six high Arctic lakes near Resolute Bay, Nunavut, Canada, using stable carbon (δ13C) and nitrogen (δ15N) isotopes and measured Hg (total Hg (THg) in char, the only fish species, and methylmercury (MeHg) in chironomids and zooplankton) concentrations in biota collected in 2010 and 2011. Across lakes, δ13C showed that benthic carbon (chironomids) was the dominant food source for char. Regression models of log Hg versus δ15N (of char and benthic invertebrates) showed positive and significant slopes, indicting Hg biomagnification in all lakes, and higher slopes in some lakes than others. However, no principal components (PC) generated using all water chemistry data and physical characteristics of the lakes predicted the different slopes. The PC dominated by aqueous ions was a negative predictor of MeHg concentrations in chironomids, suggesting that water chemistry affects Hg bioavailability and MeHg concentrations in these lower-trophic-level organisms. Furthermore, regression intercepts were predicted by the PCs dominated by catchment area, aqueous ions, and MeHg. Weaker relationships were also found between THg in small char or MeHg in pelagic invertebrates and the PCs dominated by catchment area, and aqueous nitrate and MeHg. Results from these high Arctic lakes suggest that Hg biomagnification differs between systems and that their physical and chemical characteristics affect Hg concentrations in lower-trophic-level biota. - Highlights: • Mercury (Hg) in Arctic char and invertebrates from 6 Arctic lakes were

  18. Factors affecting biotic mercury concentrations and biomagnification through lake food webs in the Canadian high Arctic

    Energy Technology Data Exchange (ETDEWEB)

    Lescord, Gretchen L., E-mail: glescord@gmail.com [University of New Brunswick/Canadian Rivers Institute, 100 Tucker Park Rd, Saint John, NB E2L 4A6 (Canada); Kidd, Karen A. [University of New Brunswick/Canadian Rivers Institute, 100 Tucker Park Rd, Saint John, NB E2L 4A6 (Canada); Kirk, Jane L. [Environment Canada, Aquatic Contaminants Research Division, 867 Lakeshore Rd, Burlington, ON L7S 1A1 (Canada); O' Driscoll, Nelson J. [Acadia University, 15 University Ave, Wolfville, NS B4P 2R6 (Canada); Wang, Xiaowa; Muir, Derek C.G. [Environment Canada, Aquatic Contaminants Research Division, 867 Lakeshore Rd, Burlington, ON L7S 1A1 (Canada)

    2015-03-15

    In temperate regions of Canada, mercury (Hg) concentrations in biota and the magnitude of Hg biomagnification through food webs vary between neighboring lakes and are related to water chemistry variables and physical lake features. However, few studies have examined factors affecting the variable Hg concentrations in landlocked Arctic char (Salvelinus alpinus) or the biomagnification of Hg through their food webs. We estimated the food web structure of six high Arctic lakes near Resolute Bay, Nunavut, Canada, using stable carbon (δ{sup 13}C) and nitrogen (δ{sup 15}N) isotopes and measured Hg (total Hg (THg) in char, the only fish species, and methylmercury (MeHg) in chironomids and zooplankton) concentrations in biota collected in 2010 and 2011. Across lakes, δ{sup 13}C showed that benthic carbon (chironomids) was the dominant food source for char. Regression models of log Hg versus δ{sup 15}N (of char and benthic invertebrates) showed positive and significant slopes, indicting Hg biomagnification in all lakes, and higher slopes in some lakes than others. However, no principal components (PC) generated using all water chemistry data and physical characteristics of the lakes predicted the different slopes. The PC dominated by aqueous ions was a negative predictor of MeHg concentrations in chironomids, suggesting that water chemistry affects Hg bioavailability and MeHg concentrations in these lower-trophic-level organisms. Furthermore, regression intercepts were predicted by the PCs dominated by catchment area, aqueous ions, and MeHg. Weaker relationships were also found between THg in small char or MeHg in pelagic invertebrates and the PCs dominated by catchment area, and aqueous nitrate and MeHg. Results from these high Arctic lakes suggest that Hg biomagnification differs between systems and that their physical and chemical characteristics affect Hg concentrations in lower-trophic-level biota. - Highlights: • Mercury (Hg) in Arctic char and invertebrates

  19. Biogeography and Photosynthetic Biomass of Arctic Marine Pico-Eukaroytes during Summer of the Record Sea Ice Minimum 2012.

    Science.gov (United States)

    Metfies, Katja; von Appen, Wilken-Jon; Kilias, Estelle; Nicolaus, Anja; Nöthig, Eva-Maria

    2016-01-01

    Information on recent photosynthetic biomass distribution and biogeography of Arctic marine pico-eukaryotes (0.2-3 μm) is needed to better understand consequences of environmental change for Arctic marine ecosystems. We analysed pico-eukaryote biomass and community composition in Fram Strait and large parts of the Central Arctic Ocean (Nansen Basin, Amundsen Basin) using chlorophyll a (Chl a) measurements, automated ribosomal intergenic spacer analysis (ARISA) and 454-pyrosequencing. Samples were collected during summer 2012, the year with the most recent record sea ice minimum. Chl a concentrations were highest in eastern Fram Strait and pico-plankton accounted for 60-90% of Chl a biomass during the observation period. ARISA-patterns and 454-pyrosequencing revealed that pico-eukaryote distribution is closely related to water mass distribution in the euphotic zone of the Arctic Ocean. Phaeocystaceae, Micromonas sp., Dinophyceae and Syndiniales constitute a high proportion of sequence reads, while sequence abundance of autotrophic Phaeocystaceae and mixotrophic Micromonas sp. was inversely correlated. Highest sequence abundances of Phaeocystaceae were observed in the warm Atlantic Waters in Fram Strait, while Micromonas sp. dominated the abundant biosphere in the arctic halocline. Our results are of particular interest considering existing hypotheses that environmental conditions in Nansen Basin might become more similar to the current conditions in Fram Strait. We propose that in response, biodiversity and biomass of pico-eukaryotes in Nansen Basin could resemble those currently observed in Fram Strait in the future. This would significantly alter biogeochemical cycles in a large part of the Central Arctic Ocean. PMID:26895333

  20. Biogeography and Photosynthetic Biomass of Arctic Marine Pico-Eukaroytes during Summer of the Record Sea Ice Minimum 2012.

    Directory of Open Access Journals (Sweden)

    Katja Metfies

    Full Text Available Information on recent photosynthetic biomass distribution and biogeography of Arctic marine pico-eukaryotes (0.2-3 μm is needed to better understand consequences of environmental change for Arctic marine ecosystems. We analysed pico-eukaryote biomass and community composition in Fram Strait and large parts of the Central Arctic Ocean (Nansen Basin, Amundsen Basin using chlorophyll a (Chl a measurements, automated ribosomal intergenic spacer analysis (ARISA and 454-pyrosequencing. Samples were collected during summer 2012, the year with the most recent record sea ice minimum. Chl a concentrations were highest in eastern Fram Strait and pico-plankton accounted for 60-90% of Chl a biomass during the observation period. ARISA-patterns and 454-pyrosequencing revealed that pico-eukaryote distribution is closely related to water mass distribution in the euphotic zone of the Arctic Ocean. Phaeocystaceae, Micromonas sp., Dinophyceae and Syndiniales constitute a high proportion of sequence reads, while sequence abundance of autotrophic Phaeocystaceae and mixotrophic Micromonas sp. was inversely correlated. Highest sequence abundances of Phaeocystaceae were observed in the warm Atlantic Waters in Fram Strait, while Micromonas sp. dominated the abundant biosphere in the arctic halocline. Our results are of particular interest considering existing hypotheses that environmental conditions in Nansen Basin might become more similar to the current conditions in Fram Strait. We propose that in response, biodiversity and biomass of pico-eukaryotes in Nansen Basin could resemble those currently observed in Fram Strait in the future. This would significantly alter biogeochemical cycles in a large part of the Central Arctic Ocean.

  1. FRAM-2012: Norwegians return to the High Arctic with a Hovercraft for Marine Geophysical Research

    Science.gov (United States)

    Hall, J. K.; Kristoffersen, Y.; Brekke, H.; Hope, G.

    2012-12-01

    After four years of testing methods, craft reliability, and innovative equipment, the R/H SABVABAA has embarked on its first FRAM-201x expedition to the highest Arctic. Named after the Inupiaq word for 'flows swiftly over it', the 12m by 6m hovercraft has been home-based in Longyearbyen, Svalbard since June 2008. In this, its fifth summer of work on the ice pack north of 81N, the craft is supported by the Norwegian Petroleum Directorate (NPD) via the Nansen Environmental and Remote Sensing Center (NERSC) in Bergen, and the Norwegian Scientific Academy for Polar Research. FRAM-2012 represents renewed Norwegian interest in returning to the highest Arctic some 116 years after the 1893-96 drift of Fridtjof Nansen's ship FRAM, the first serious scientific investigation of the Arctic. When replenished by air or icebreaker, the hovercraft Sabvabaa offers a hospitable scientific platform with crew of two, capable of marine geophysical, geological and oceanographic observations over long periods with relative mobility on the ice pack. FRAM-2012 is the first step towards this goal, accompanying the Swedish icebreaker ODEN to the Lomonosov Ridge, north of Greenland, as part of the LOMROG III expedition. The science plan called for an initial drive from the ice edge to Gakkel Ridge at 85N where micro-earthquakes would be monitored, and then to continue north to a geological sampling area on the Lomonosov Ridge at about 88N, 65W. The micro-earthquake monitoring is part of Gaute Hope's MSc thesis and entails five hydrophones in a WiFi-connected hydrophone array deployed over the Gakkel Rift Valley, drifting with the ice at up to 0.4 knots. On August 3 the hovercraft was refueled from icebreaker ODEN at 84-21'N and both vessels proceeded north. The progress of the hovercraft was hampered by insufficient visibility for safe driving and time consuming maneuvering in and around larger fields of rubble ice impassable by the hovercraft, but of little concern to the icebreaker. It

  2. Oil spill related contaminant data for Arctic marine mammals - Obtaining baseline oil spill-related contaminant exposure data for Arctic marine mammals

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — With increasing oil exploration and ship traffic in the U.S. Arctic, there is concern about the increased potential for an oil spill event in this region of the...

  3. Relative sea level and coastal environments in arctic Alaska during Marine Isotope Stage 5

    Science.gov (United States)

    Farquharson, L. M.; Mann, D. H.; Jones, B. M.; Rittenour, T. M.; Grosse, G.; Groves, P.

    2015-12-01

    Marine Isotope Stage (MIS) 5 was characterized by marked fluctuations in climate, the warmest being MIS 5e (124-119 ka) when relative sea level (RSL) stood 2-10 m higher than today along many coastlines. In northern Alaska, marine deposits now 5-10 m above modern sea level are assigned to this time period and termed the Pelukian transgression (PT). Complicating this interpretation is the possibility that an intra-Stage 5 ice shelf extended along the Alaskan coast, causing isostatic depression along its grounded margins, which caused RSL highs even during periods of low, global RSL. Here we use optically stimulated luminescence (OSL) to date inferred PT deposits on the Beaufort Sea coastal plain. A transition from what we interpret to be lagoonal mud to sandy tidal flat deposits lying ~ 2.75 m asl dates to 113+/-18 ka. Above this, a 5-m thick gravelly barrier beach dates to 95 +/- 20 ka. This beach contains well-preserved marine molluscs, whale vertebrae, and walrus tusks. Pleistocene-aged ice-rich eolian silt (yedoma) blanket the marine deposits and date to 57.6 +/-10.9 ka. Our interpretation of this chronostratigraphy is that RSL was several meters higher than today during MIS 5e, and lagoons or brackish lakes were prevalent. Gravel barrier beaches moved onshore as local RSL rose further after MIS 5e. The error range of the OSL age of the barrier-beach unit spans the remaining four substages of MIS 5; however, the highstand of RSL on this arctic coastline appears to occurr after the warmest part of the last interglacial and appears not to be coeval with the eustatic maximum reached at lower latitudes during MIS 5. One possibility is that RSL along the Beaufort Sea coast was affected by isostatic depression caused by an ice shelf associated with widespread, intra-Stage 5 glaciation that was out of phase with lower latitude glaciation and whose extent and timing remains enigmatic.

  4. Biochemical Characterization of a Family 15 Carbohydrate Esterase from a Bacterial Marine Arctic Metagenome

    Science.gov (United States)

    De Santi, Concetta; Willassen, Nils Peder

    2016-01-01

    Background The glucuronoyl esterase enzymes of wood-degrading fungi (Carbohydrate Esterase family 15; CE15) form part of the hemicellulolytic and cellulolytic enzyme systems that break down plant biomass, and have possible applications in biotechnology. Homologous enzymes are predicted in the genomes of several bacteria, however these have been much less studied than their fungal counterparts. Here we describe the recombinant production and biochemical characterization of a bacterial CE15 enzyme denoted MZ0003, which was identified by in silico screening of a prokaryotic metagenome library derived from marine Arctic sediment. MZ0003 has high similarity to several uncharacterized gene products of polysaccharide-degrading bacterial species, and phylogenetic analysis indicates a deep evolutionary split between these CE15s and fungal homologs. Results MZ0003 appears to differ from previously-studied CE15s in some aspects. Some glucuronoyl esterase activity could be measured by qualitative thin-layer chromatography which confirms its assignment as a CE15, however MZ0003 can also hydrolyze a range of other esters, including p-nitrophenyl acetate, which is not acted upon by some fungal homologs. The structure of MZ0003 also appears to differ as it is predicted to have several large loop regions that are absent in previously studied CE15s, and a combination of homology-based modelling and site-directed mutagenesis indicate its catalytic residues deviate from the conserved Ser-His-Glu triad of many fungal CE15s. Taken together, these results indicate that potentially unexplored diversity exists among bacterial CE15s, and this may be accessed by investigation of the microbial metagenome. The combination of low activity on typical glucuronoyl esterase substrates, and the lack of glucuronic acid esters in the marine environment suggest that the physiological substrate of MZ0003 and its homologs is likely to be different from that of related fungal enzymes. PMID:27433797

  5. Biochemical Characterization of a Family 15 Carbohydrate Esterase from a Bacterial Marine Arctic Metagenome.

    Directory of Open Access Journals (Sweden)

    Concetta De Santi

    Full Text Available The glucuronoyl esterase enzymes of wood-degrading fungi (Carbohydrate Esterase family 15; CE15 form part of the hemicellulolytic and cellulolytic enzyme systems that break down plant biomass, and have possible applications in biotechnology. Homologous enzymes are predicted in the genomes of several bacteria, however these have been much less studied than their fungal counterparts. Here we describe the recombinant production and biochemical characterization of a bacterial CE15 enzyme denoted MZ0003, which was identified by in silico screening of a prokaryotic metagenome library derived from marine Arctic sediment. MZ0003 has high similarity to several uncharacterized gene products of polysaccharide-degrading bacterial species, and phylogenetic analysis indicates a deep evolutionary split between these CE15s and fungal homologs.MZ0003 appears to differ from previously-studied CE15s in some aspects. Some glucuronoyl esterase activity could be measured by qualitative thin-layer chromatography which confirms its assignment as a CE15, however MZ0003 can also hydrolyze a range of other esters, including p-nitrophenyl acetate, which is not acted upon by some fungal homologs. The structure of MZ0003 also appears to differ as it is predicted to have several large loop regions that are absent in previously studied CE15s, and a combination of homology-based modelling and site-directed mutagenesis indicate its catalytic residues deviate from the conserved Ser-His-Glu triad of many fungal CE15s. Taken together, these results indicate that potentially unexplored diversity exists among bacterial CE15s, and this may be accessed by investigation of the microbial metagenome. The combination of low activity on typical glucuronoyl esterase substrates, and the lack of glucuronic acid esters in the marine environment suggest that the physiological substrate of MZ0003 and its homologs is likely to be different from that of related fungal enzymes.

  6. Isolation and phylogenetic assignation of actinomycetes in the marine sediments from the Arctic Ocean

    Institute of Scientific and Technical Information of China (English)

    YU Yong; LI Huirong; ZENG Yinxin; CHEN Bo

    2005-01-01

    Actinomycetes in five marine sediments collected from the Arctic Ocean at depths of 43 to 3 050 m were cultivated using a variety of media. A total of 61 actinomycete colonies with substrate mycelia only were observed, and no colonies with aerial mycelia were observed under aerobic conditions at 15 ℃. From these colonies, 28 were selected to represent different morphological types.Denaturing gradient gel electrophoresis (DGGE) was used to check the purity of isolates and select representatives for subsequent sequencing. Phylogentic analyses based on nearly full-length 16S ribosomal RNA gene (rDNA) sequences indicated that the actinomycetes isolated were accommodated within genus Rhodococcus of family Nocardiaceae, genus Dietzia of family Dietziaceae,genera Janibacter and Terrabacter of family Instrasporangiaceae and genera Kocuria and Arthrobacter of family Micrococcaceae. One of the strains (P27-24) from the deep-sea sediment at depth of 3 050 m was found to be identical in 16S rDNA sequence(1474/1474)with the radiation-resistant Kocuria rosea ATCC 187T isolated from air. More than halfofthe isolates showed the similarities ranging from 99.5% to 99.9% in 16S rDNA sequence to dibenzofran-degrading, butyl 2-ethylhexanoate-hydrolysising and nitrile-metabolizing actinomycetes. All the strains isolated were psychrotolerant bacteria and grew better on the media prepared with natural seawater than on the media prepared with deionized water. Three of them (Dietzia sp. P27-10, Rhodococcus sp. S11-3 and Rhodococcus sp.P11-5)had an obligate growth requirement for salt, confirming that these strains are indigenous marine actinomycetes.

  7. Performance of concrete after 10 years of exposure in the Arctic marine environment

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, M.H. [National University of Singapore (Singapore); Bilodeau, A.; Malhotra, V.M. [Natural Resources Canada, Ottawa, ON (Canada)

    2001-07-01

    A study was conducted to test the service life of concrete that has been exposed to an Arctic marine environment for 10 years. A total of 12 concrete panels were installed at a site at Nanisivik, Baffin Island, Northwest Territories, Canada. Six of the panels were made with normal-weight aggregate concrete, the others with concrete mixed with expanded shale lightweight aggregate. Steel fibres were also in the cement and the portland cement was replaced with fly ash, slag, silica fume or a combination of fly ash and silica fume. The panels were then visually inspected and cores were also taken to determine the chloride content at various depths from the exposure surface. It was shown that after 10 years of exposure, the panel made of normal weight aggregate did not show much loss of mass from ice abrasion. However, panels made with lightweight aggregate showed mass loss, particularly on the surfaces exposed to the tidal zone. Less damage and cracking was observed in the steel fibre-reinforced panels. Mixtures with fly ash, slag or silica fume showed better resistance to chloride penetration. The use of normal weight limestone aggregate or expanded shale lightweight aggregate did not make a difference in the resistance of the concrete to chloride-ion penetration for non-fibre-reinforced portland cement concrete, but a difference was noted for fibre-reinforced portland cement concrete. Those made with lightweight aggregate materials exhibited a lower chloride-ion content. 7 refs., 10 tabs., 19 figs.

  8. The Marine Food Chain in Relation to Biodiversity

    Directory of Open Access Journals (Sweden)

    Andrew R.G. Price

    2001-01-01

    Full Text Available Biodiversity provides “raw materials” for the food chain and seafood production, and also influences the capacity of ecosystems to perform these and other services. Harvested marine seafood species now exceed 100 million t y -1 and provide about 6% of all protein and 17% of animal protein consumed by humans. These resources include representatives from about nine biologically diverse groups of plants and animals. Fish account for most of the world’s marine catches, of which only 40 species are taken in abundance. Highest primary productivity and the richest fisheries are found within Exclusive Economic Zones (EEZ. This narrow strip (200 nautical mile/370 km wide is not only the site of coastal “food factories” but also the area associated with heaviest perturbation to the marine environment. Structural redundancy is evident in marine ecosystems, in that many species are interchangeable in the way they characterise assemblage composition. While there is probably functional redundancy within groups, the effects of species loss on ecosystem performance cannot be easily predicted. In particular, the degree to which biodiversity per se is needed for ecosystem services, including seafood/fishery production, is poorly understood. Many human activities, including unsustainable fishing and mariculture, lead to erosion of marine biodiversity. This can undermine the biophysical cornerstones of fisheries and have other undesirable environmental side effects. Of direct concern are “species effects”, in particular the removal of target and non-target fishery species, as well as conservationally important fauna. Equally disrupting but less immediate are “ecosystem effects”, such as fishing down the food web, following a shift from harvested species of high to low trophic level. Physical and biological disturbances from trawl nets and dynamite fishing on coral reefs can also severely impact ecosystem structure and function.

  9. Comparative analysis of land, marine, and satellite observations of methane in the lower Atmosphere in the Russian Arctic under conditions of climate change

    Science.gov (United States)

    Anisimov, O. A.; Kokorev, V. A.

    2015-12-01

    Land, marine, and satellite observations have been used to study changes in methane concentrations in the lower atmosphere during the warm months of the year (July through October) in Arctic regions having different potentials for methane production. The Atmospheric Infrared Sounder (AIRS) data for 2002-2013 are used to explore the interplay between local methane sources in the terrestrial region of the Eurasian Arctic and on the Arctic shelf over the warm period of the year. Linear trends in atmospheric methane concentrations over different Arctic regions are calculated, and a hypothesis of the relation of concentration variations to climatic parameters is tested. The combination of land, marine, and satellite observation is used to develop a conceptual model of the atmospheric methane field in the terrestrial part of the Russian Arctic and on the Arctic shelf. It is shown that the modern methane growth rate in the Arctic does not exceed the Northern Hemisphere mean. It is concluded that the methane emission in the Arctic has little effect on global climate compared to other factors.

  10. Pollution of the Marine Environment by Dumping: Legal Framework Applicable to Dumped Chemical Weapons and Nuclear Waste in the Arctic Ocean

    Directory of Open Access Journals (Sweden)

    Lott, Alexander

    2016-06-01

    Full Text Available The Arctic seas are the world’s biggest dumping ground for sea-disposed nuclear waste and have served among the primary disposal sites for chemical warfare agents. Despite of scientific uncertainty, the Arctic Council has noted that this hazardous waste still affects adversely the Arctic marine environment and may have implications to the health of the Arctic people. The purpose of this manuscript is to establish the rights and obligations of the Arctic States in connection with sea-dumped chemical weapons and nuclear material under international law of the sea, international environmental law and disarmament law. Such mapping is important for considering options to tackle the pollution to the Arctic ecosystems and because there seems to be yet no such analysis across the legal fields carried out. This paper aims first at identifying the scale and approximate locations of sea-disposed nuclear waste and chemical weapons in the Arctic Ocean. The analysis will further focus on ascertaining the possibilities to minimize their adverse effects on the Arctic marine environment under the applicable legal framework. It will be argued in this manuscript that due to the corrosion of the chemical weapons and nuclear material containers, recovering, rather than confining this hazardous waste might be counterproductive as it might cause a sudden and widespread release of chemical agents or radionuclides when surfacing. In this regard, carrying out an environmental impact assessment prior to each such remediation operation would be necessary to determine the most suitable technique for minimizing or eliminating pollution.

  11. Pollution of the Marine Environment by Dumping: Legal Framework Applicable to Dumped Chemical Weapons and Nuclear Waste in the Arctic Ocean

    Directory of Open Access Journals (Sweden)

    Lott, Alexander

    2015-06-01

    Full Text Available The Arctic seas are the world’s biggest dumping ground for sea-disposed nuclear waste and have served among the primary disposal sites for chemical warfare agents. Despite of scientific uncertainty, the Arctic Council has noted that this hazardous waste still affects adversely the Arctic marine environment and may have implications to the health of the Arctic people. The purpose of this manuscript is to establish the rights and obligations of the Arctic States in connection with sea-dumped chemical weapons and nuclear material under international law of the sea, international environmental law and disarmament law. Such mapping is important for considering options to tackle the pollution to the Arctic ecosystems and because there seems to be yet no such analysis across the legal fields carried out. This paper aims first at identifying the scale and approximate locations of sea-disposed nuclear waste and chemical weapons in the Arctic Ocean. The analysis will further focus on ascertaining the possibilities to minimize their adverse effects on the Arctic marine environment under the applicable legal framework. It will be argued in this manuscript that due to the corrosion of the chemical weapons and nuclear material containers, recovering, rather than confining this hazardous waste might be counterproductive as it might cause a sudden and widespread release of chemical agents or radionuclides when surfacing. In this regard, carrying out an environmental impact assessment prior to each such remediation operation would be necessary to determine the most suitable technique for minimizing or eliminating pollution.

  12. Persistent organic pollutant and mercury concentrations in eggs of ground-nesting marine birds in the Canadian high Arctic.

    Science.gov (United States)

    Peck, Liam E; Gilchrist, H Grant; Mallory, Conor D; Braune, Birgit M; Mallory, Mark L

    2016-06-15

    We collected eggs of eight marine bird species from several colony sites in the Canadian high Arctic located at approximately 76°N and analyzed them for concentrations of legacy persistent organic pollutants (POPs) and mercury. We provide the first report on concentrations of POPs in eggs of three Arctic species (Thayer's gull Larus thayeri, Sabine's gull Xema sabini, Ross's Gull Rhodostethia rosea), and we found significant differences in each of the POP profiles among the five species with sufficient data for statistical comparisons (Thayer's gull, black guillemot Cepphus grylle, Sabine's gull, Arctic tern Sterna paradisaea and common eider Somateria mollissima borealis). The Ross's Gull had unexpectedly high POP concentrations relative to the other species examined, although this was based on a single egg, while glaucous gull Larus hyperboreus eggs from our sampling location had very low POPs. Sabine's gulls had the lowest Hg of the eggs studied, consistent with their low trophic position, but concentrations of their legacy POPs were higher than expected. We also noted that total hexachlorocyclohexanes were higher than reported elsewhere in the circumpolar Arctic in three species. PMID:26971212

  13. Food and water security issues in Russia I: food security in the general population of the Russian Arctic, Siberia and the Far East, 2000–2011

    Science.gov (United States)

    Dudarev, Alexey A.; Alloyarov, Pavel R.; Chupakhin, Valery S.; Dushkina, Eugenia V.; Sladkova, Yuliya N.; Dorofeyev, Vitaliy M.; Kolesnikova, Tatijana A.; Fridman, Kirill B.; Nilsson, Lena Maria; Evengård, Birgitta

    2013-01-01

    Background Problems related to food security in Russian Arctic (dietary imbalance, predominance of carbohydrates, shortage of milk products, vegetables and fruits, deficit of vitamins and microelements, chemical, infectious and parasitic food contamination) have been defined in the literature. But no standard protocol of food security assessment has been used in the majority of studies. Objectives Our aim was to obtain food security indicators, identified within an Arctic collaboration, for selected regions of the Russian Arctic, Siberia and the Far East, and to compare food safety in these territories. Study design and methods In 18 regions of the Russian Arctic, Siberia and the Far East, the following indicators of food security were analyzed: food costs, food consumption, and chemical and biological food contamination for the period 2000–2011. Results Food costs in the regions are high, comprising 23–43% of household income. Only 4 out of 10 food groups (fish products, cereals, sugar, plant oil) are consumed in sufficient amounts. The consumption of milk products, eggs, vegetables, potatoes, fruits (and berries) is severely low in a majority of the selected regions. There are high levels of biological contamination of food in many regions. The biological and chemical contamination situation is alarming, especially in Chukotka. Only 7 food pollutants are under regular control; among pesticides, only DDT. Evenki AO and Magadan Oblast have reached peak values in food contaminants compared with other regions. Mercury in local fish has not been analyzed in the majority of the regions. In 3 regions, no monitoring of DDT occurs. Aflatoxins have not been analyzed in 5 regions. Nitrates had the highest percentage in excess of the hygienic threshold in all regions. Excesses of other pollutants in different regions were episodic and as a rule not high. Conclusion Improvement of the food supply and food accessibility in the regions of the Russian Arctic, Siberia and the

  14. Food and water security issues in Russia I: food security in the general population of the Russian Arctic, Siberia and the Far East, 2000–2011

    Directory of Open Access Journals (Sweden)

    Alexey A. Dudarev

    2013-10-01

    Full Text Available Background. Problems related to food security in Russian Arctic (dietary imbalance, predominance of carbohydrates, shortage of milk products, vegetables and fruits, deficit of vitamins and microelements, chemical, infectious and parasitic food contamination have been defined in the literature. But no standard protocol of food security assessment has been used in the majority of studies. Objectives. Our aim was to obtain food security indicators, identified within an Arctic collaboration, for selected regions of the Russian Arctic, Siberia and the Far East, and to compare food safety in these territories. Study design and methods. In 18 regions of the Russian Arctic, Siberia and the Far East, the following indicators of food security were analyzed: food costs, food consumption, and chemical and biological food contamination for the period 2000–2011. Results. Food costs in the regions are high, comprising 23–43% of household income. Only 4 out of 10 food groups (fish products, cereals, sugar, plant oil are consumed in sufficient amounts. The consumption of milk products, eggs, vegetables, potatoes, fruits (and berries is severely low in a majority of the selected regions. There are high levels of biological contamination of food in many regions. The biological and chemical contamination situation is alarming, especially in Chukotka. Only 7 food pollutants are under regular control; among pesticides, only DDT. Evenki AO and Magadan Oblast have reached peak values in food contaminants compared with other regions. Mercury in local fish has not been analyzed in the majority of the regions. In 3 regions, no monitoring of DDT occurs. Aflatoxins have not been analyzed in 5 regions. Nitrates had the highest percentage in excess of the hygienic threshold in all regions. Excesses of other pollutants in different regions were episodic and as a rule not high. Conclusion. Improvement of the food supply and food accessibility in the regions of the Russian

  15. A Potential Impact on the Chemical Composition in the Marine Boundary Layer in the Arctic Ocean by Ship Emissions

    Science.gov (United States)

    Xie, Z.; Wang, X.; Blum, J. D.; Sun, L.

    2005-12-01

    Samples of aerosols in the marine boundary layer (MBL) of the Arctic Ocean were collected aboard R/V ()Xuelong during the summer on the Second Chinese Arctic Research Expedition (July-September, 2003). Chemical compositions including major and trace elements and polycyclic aromatic hydrocarbons (PAHs) in aerosol particles were analyzed. Results showed that significant amounts of S, Fe, V and Ni are emitted from ship diesel engines and contaminate the ambient air. The total amount of Fe, which plays a significant role in the ocean ()biological pump, emitted from ships in the Arctic is estimated at 4.33-A106 kg yr-1. Sulfur emitted into the atmosphere may be transformed to sulfur acid and result in a chlorine depletion in sea-salt. Because the global inventory of sulfur from ship exhausts is large and halogens may have important consequences in possible tropospheric ozone destruction, the role of ships in effecting halogen depression in sea-salt should be evaluated. For organic compounds, 17 PAHs including Fluoranthene, Phenanthrene, Chrysene, Indeno[123-cd]pyrene, Pyrene, Benzo[b]fluoranthene, Benzo[ghi]pyrene, Naphthalene, Benzo[a]anthracene, Benzo[k]fluoranthene, Coronene, Fluorene, Benzo[a]pyrene, Acenaphthene, Anthracene, Dibenzo[a,h]anthracene and Acenaphthylene were detected. The average levels of subspecies of PAHs in ambient air ranged from 0.003 to 0.089 ng/m3. Among the 17 PAHs, fluoranthene had a relative high level, while the level of acenaphthylene was relative low. The aerosols contaminated by the ship, which were commonly excluded in previous investigations, thus provide an opportunity to investigate and understand the role of ship emissions in the atmospheric chemistry of the marine boundary layer, especially in the Arctic Ocean.

  16. Krill community composition and grazing biology in a sub-Arctic Greenlandic fjord

    DEFF Research Database (Denmark)

    Teglhus, Frederik Wolff; Agersted, Mette Dalgaard; Arendt, Kristine Engel;

    Several studies have described the role of copepods in Arctic marine food webs. However, knowledge about larger zooplankton organisms like krill are very limited. Krill is an important food source for many marine animals and they are potentially a significant contributor to the vertical flux...

  17. Atmospheric mercury over the marine boundary layer observed during the third China Arctic Research Expedition

    Institute of Scientific and Technical Information of China (English)

    Hui Kang; Zhouqing Xie

    2011-01-01

    TGM measurements on board ships have proved to provide valuable complementary information to measurements by a ground based monitoring network.During the third China Arctic Research Expedition (from July 11 to September 24,2008),TGM concentrations over the marine boundary layer along the cruise path were in-situ measured using an automatic mercury vapor analyzer.Here we firstly reported the results in Japan Sea,North Western Pacific Ocean and Bering Sea,where there are rare reports.The value ranged between 0.30 and 6.02 ng/m3 with an average of (1.52 ± 0.68) ng/m3,being slightly lower than the background value of Northern Hemisphere (1.7 ng/m3).Notably TGM showed considerably spatial and temporal variation.Geographically,the average value of TGM in Bering Sea was higher than those observed in Japan Sea and North Western Pacific Ocean.In the north of Japan Sea TGM levels were found to be lower than 0.5 ng/m3 during forward cruise and displayed obviously diurnal cycle,indicating potential oxidation of gaseous mercury in the atmosphere.The pronounced episode was recorded as well.Enhanced levels of TGM were observed in the coastal regions of southern Japan Sea during backward cruise due primarily to air masses transported from the adjacent mainland reflecting the contribution from anthropogenic sources.When ship returned back and passed through Kamchatka Peninsula TGM increased by the potential contamination from volcano emissions.

  18. Marine and ice landscapes of the Arctic and Sub-arctic in the course of towering industrial activity: ability of the management with using documentation facilities of satellite ecological criminalistics

    Science.gov (United States)

    Melentyev, Vladimir; Vladimirovich Melentyev, Konstantin; Petterssen, Lasse Herbert; Andreevna Zakharova, Tatiana

    2013-04-01

    In our studies we are following for the classification of the marine and ice landscapes of the Arctic that was suggested by prof. Ye.S. Korotkevich who had provided summarizing results of the long-term in situ field experiments and airborne studies that was fulfilled by scientists of Arctic and Antarctic Research Institute (AARI) under his leadership in Russian Arctic after the 2-nd World War. But satellite multispectral observations show significant temporal and spatial modification of the suggested scheme especially for Arctic ice landscapes that had occurred in nowadays due to the climate change and anthropogenic press. Design main principle and rules of satellite ecological criminalistics - science of crime detection of ecocatastrophe and incidents on sea and fresh waters with using aerospace survey as well for the control, for the management and the preventing of ecological instability of the marine and lakes ecosystems was done by Academician Kirill Kondratiev together with his apprentices and follower in 1970-s. In frame proposed paper we shall present results of our comprehensive satellite-airborne studies of the marine and ice landscapes as well discuss the incidents that happened in Arctic inside the inland and international waters in past and present days and were revealed with using multispectral remote sensing. But for all that we need to mention that our contemporary investigations are based on the all-weather satellite ERS-1/2 - Envisat - RADARSAT SAR survey archived since 1990-s by SUAI and NERSC/NIERSC.

  19. Invasions and extinctions reshape coastal marine food webs.

    Science.gov (United States)

    Byrnes, Jarrett E; Reynolds, Pamela L; Stachowicz, John J

    2007-01-01

    The biodiversity of ecosystems worldwide is changing because of species loss due to human-caused extinctions and species gain through intentional and accidental introductions. Here we show that the combined effect of these two processes is altering the trophic structure of food webs in coastal marine systems. This is because most extinctions ( approximately 70%) occur at high trophic levels (top predators and other carnivores), while most invasions are by species from lower trophic levels (70% macroplanktivores, deposit feeders, and detritivores). These opposing changes thus alter the shape of marine food webs from a trophic pyramid capped by a diverse array of predators and consumers to a shorter, squatter configuration dominated by filter feeders and scavengers. The consequences of the simultaneous loss of diversity at top trophic levels and gain at lower trophic levels is largely unknown. However, current research suggests that a better understanding of how such simultaneous changes in diversity can impact ecosystem function will be required to manage coastal ecosystems and forecast future changes. PMID:17356703

  20. Volatile fatty acids as substrates for iron and sulfate reduction in Arctic marine sediments, Svalbard

    Science.gov (United States)

    Finke, N.; Vandieken, V.; Jorgensen, B. B.

    2006-12-01

    Anaerobic degradation of complex organic material in aquatic systems is a multi-step process. The metabolic products of fermentative bacteria serve as electron donors for the terminal oxidizing bacteria. In marine sediments, iron reduction and sulfate reduction are generally the most important terminal oxidation processes in the upper anoxic zone [1]. Microorganisms that reduce iron and sulfate may use a broad range of electron donors, yet the list of potential substrates provides little information about the substrates used in situ by these organisms. Investigations on the electron donors for sulfate reducers in marine sediments have shown that volatile fatty acids (VFA), and in particular acetate, together with hydrogen are the major substrates (e.g. [2-4]). Similar investigations for iron reduction or simultaneous iron and sulfate reduction are lacking for marine sediments. Furthermore, most of these studies were made in temperate sediments and little is known about the substrates for sulfate reducers in permanently cold sediments, which account for >90% of the ocean floor [5]. We investigated the relative contributions of iron reduction and sulfate reduction to the terminal oxidation of organic carbon and the importance of acetate, lactate, propionate, and isobutyrate as electron donors for iron and sulfate reduction in permanently cold, Arctic sediments from Svalbard. In the surface layer (0-2 cm) sulfate reduction accounted for 2/3 of the organic carbon oxidation (determined as DIC production), the remaining 1/3 were attributed to iron reduction. In the 5-9 cm layer sulfate reduction was the sole important terminal oxidation step. The contribution of acetate to terminal oxidation was determined by radiotracer incubation as well as from the accumulation after the inhibition of sulfate reduction by selenate. The rates determined with the two methods varied by less than 20%. Acetate turnover, determined with the tracer incubations, accounted for 10 and 40% of

  1. Calanus glacialis : the role of lipids in the life cycle and for the Arctic pelagic food web

    OpenAIRE

    Wold, Anette

    2012-01-01

    The Arctic marine ecosystem is characterized by strong seasonality and a short but productive period of primary production in the spring when the ice breaks up. Calanus glacialis is one of the key links between primary producers and higher trophic levels, and it is adapted to the strong seasonality by life cycle traits such as; seasonal vertical migration, diapausing, reproduction in the spring and extensive energy storage. The timing of these events will have consequences for the success of ...

  2. Concentrations of 17 elements, including mercury, in the tissues, food and abiotic environment of Arctic shorebirds

    International Nuclear Information System (INIS)

    Exposure to contaminants is one hypothesis proposed to explain the global decline in shorebirds, and is also an increasing concern in the Arctic. We assessed potential contaminants (As, Be, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, Tl, V, and Zn) at a shorebird breeding site in Nunavut, Canada. We compared element levels in soil, invertebrates and shorebird blood to assess evidence for bioconcentration and biomagnification within the Arctic-based food chain. We tested whether elements in blood, feathers and eggs of six shorebird species (Pluvialis squatarola, Calidris alpina, C. fuscicollis, Phalaropus fulicarius, Charadrius semipalmatus, and Arenaria interpres) were related to fitness endpoints: adult body condition, blood-parasite load, egg size, eggshell thickness, nest duration, and hatching success. To facilitate comparison to other sites, we summarise the published data on toxic metals in shorebird blood and egg contents. Element concentrations and invertebrate composition differed strongly among habitats, and habitat use and element concentrations differed among shorebird species. Hg, Se, Cd, Cu, and Zn bioconcentrated from soil to invertebrates, and Hg, Se and Fe biomagnified from invertebrates to shorebird blood. As, Ni, Pb, Co and Mn showed significant biodilution from soil to invertebrates to shorebirds. Soil element levels were within Canadian guidelines, and invertebrate Hg levels were below dietary levels suggested for the protection of wildlife. However, maximum Hg in blood and eggs approached levels associated with toxicological effects and Hg-pollution in other bird species. Parental blood-Hg was negatively related to egg volume, although the relationship varied among species. No other elements approached established toxicological thresholds. In conclusion, whereas we found little evidence that exposure to elements at this site is leading to the declines of the species studied, Hg, as found elsewhere in the Canadian Arctic, is of potential

  3. Concentrations of 17 elements, including mercury, in the tissues, food and abiotic environment of Arctic shorebirds

    Energy Technology Data Exchange (ETDEWEB)

    Hargreaves, Anna L., E-mail: alhargreaves@gmail.com [Calgary Zoo, Centre for Conservation Research, 1300 Zoo Rd NE, Calgary, AB, T2E 7V6 (Canada); Whiteside, Douglas P. [Calgary Zoo, Animal Health Centre, 1300 Zoo Rd NE, Calgary, AB, T2E 7V6 (Canada); University of Calgary, Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, 2500 University Dr. NW, Calgary, AB, T2N 1N4 (Canada); Gilchrist, Grant [Carleton University, National Wildlife Research Centre, Ottawa, ON, KIA OH3 (Canada)

    2011-09-01

    Exposure to contaminants is one hypothesis proposed to explain the global decline in shorebirds, and is also an increasing concern in the Arctic. We assessed potential contaminants (As, Be, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, Tl, V, and Zn) at a shorebird breeding site in Nunavut, Canada. We compared element levels in soil, invertebrates and shorebird blood to assess evidence for bioconcentration and biomagnification within the Arctic-based food chain. We tested whether elements in blood, feathers and eggs of six shorebird species (Pluvialis squatarola, Calidris alpina, C. fuscicollis, Phalaropus fulicarius, Charadrius semipalmatus, and Arenaria interpres) were related to fitness endpoints: adult body condition, blood-parasite load, egg size, eggshell thickness, nest duration, and hatching success. To facilitate comparison to other sites, we summarise the published data on toxic metals in shorebird blood and egg contents. Element concentrations and invertebrate composition differed strongly among habitats, and habitat use and element concentrations differed among shorebird species. Hg, Se, Cd, Cu, and Zn bioconcentrated from soil to invertebrates, and Hg, Se and Fe biomagnified from invertebrates to shorebird blood. As, Ni, Pb, Co and Mn showed significant biodilution from soil to invertebrates to shorebirds. Soil element levels were within Canadian guidelines, and invertebrate Hg levels were below dietary levels suggested for the protection of wildlife. However, maximum Hg in blood and eggs approached levels associated with toxicological effects and Hg-pollution in other bird species. Parental blood-Hg was negatively related to egg volume, although the relationship varied among species. No other elements approached established toxicological thresholds. In conclusion, whereas we found little evidence that exposure to elements at this site is leading to the declines of the species studied, Hg, as found elsewhere in the Canadian Arctic, is of potential

  4. Rescaling the trophic structure of marine food webs.

    Science.gov (United States)

    Hussey, Nigel E; Macneil, M Aaron; McMeans, Bailey C; Olin, Jill A; Dudley, Sheldon F J; Cliff, Geremy; Wintner, Sabine P; Fennessy, Sean T; Fisk, Aaron T

    2014-02-01

    Measures of trophic position (TP) are critical for understanding food web interactions and human-mediated ecosystem disturbance. Nitrogen stable isotopes (δ(15) N) provide a powerful tool to estimate TP but are limited by a pragmatic assumption that isotope discrimination is constant (change in δ(15) N between predator and prey, Δ(15) N = 3.4‰), resulting in an additive framework that omits known Δ(15) N variation. Through meta-analysis, we determine narrowing discrimination from an empirical linear relationship between experimental Δ(15) N and δ(15) N values of prey consumed. The resulting scaled Δ(15) N framework estimated reliable TPs of zooplanktivores to tertiary piscivores congruent with known feeding relationships that radically alters the conventional structure of marine food webs. Apex predator TP estimates were markedly higher than currently assumed by whole-ecosystem models, indicating perceived food webs have been truncated and species-interactions over simplified. The scaled Δ(15) N framework will greatly improve the accuracy of trophic estimates widely used in ecosystem-based management. PMID:24308860

  5. Observation of surface ozone in the marine boundary layer along a cruise through the Arctic Ocean: From offshore to remote

    Science.gov (United States)

    He, Pengzhen; Bian, Lingen; Zheng, Xiangdong; Yu, Juan; Sun, Chen; Ye, Peipei; Xie, Zhouqing

    2016-03-01

    Ozone is an important reactive gas in the troposphere; it has been frequently used to estimate atmospheric oxidation capacity. However, there are few data of surface ozone over the Arctic Ocean, especially the central Arctic Ocean. Here, surface ozone in the marine boundary layer along the cruise path during the 5th Chinese Arctic Research Expedition (June to September, 2012) was investigated. The latitudes and longitudes covered in the cruise were 31.1°N-87.7°N and 9.3°E-90°E-168.4°W. The 1-h-averaged ozone varied from 9.4 ppbv to 124.5 ppbv along the cruise. The highest mixing ratios appeared in the East China Sea and the Sea of Japan while the lowest in the Chukchi Sea. The relatively high ozone levels over the East China Sea, the Sea of Japan, and offshore Iceland were caused by transport of precursors and/or ozone from the nearby continent. Ozone mixing ratio decreasing by ~ 2 ppbv/° with increasing latitude was observed during 31-45°N covering the East China Sea and the Sea of Japan, and during 62-69°N covering offshore Iceland. Over the entire Arctic Ocean, ozone levels were relatively low, varying from 9.4 ppbv to 36.1 ppbv with an average of 23.8 ± 4.6 (mean ± standard deviation) ppbv, which was not statistically different with data observed at Barrow observatory during the same period. Unlike ozone over contaminated areas, a slight increasing trend of ozone in 69-87°N was observed. This phenomenon may be ascribed to the role of both vertical transport and chemical processes due to solar radiation.

  6. Competition within the marine microalgae over the polar dark period in the Greenland Sea of high Arctic

    Institute of Scientific and Technical Information of China (English)

    Zhang Qing; Rolf Gradinger; Zhou Qingsong

    2003-01-01

    With the onset of winter, polar marine microalgae would have faced total darkness for a period of up to 6 months. A natural autumn community of Arctic sea ice microalgae was collected for dark survival experiments from the Greenland Sea during the ARKTIS-XI/2 Expedition of RV Polarstern in October 1995. After a dark period of 161 days, species dominance in the algal assemblage have changed from initially pennate diatoms to small phytoflagellates ( < 20 μm). Over the entire dark period, the mean algal growth rate was - 0.01 d-1. Nearly all diatom species had negative growth rates, while phytoflagellate abundance increased. Resting spore formation during the dark period was observed in less than 4.5% of all cells and only for dinoflagellates and the diatom Chaetoceros spp. We assume that facultative heterotrophy and energy storage are the main processes enabling survival during the dark Arctic winter. After an increase in light intensity, microalgal cells reacted with fast growth within days. Phytoflagellates had the highest growth rate, followed by Nitzschia frigida. Further investigations and experiments should focus on the mechanisms of dark survival (mixotrophy and energy storage) of polar marine microalgae.

  7. Seasonal food web structures and sympagic pelagic coupling in the European Arctic revealed by stable isotopes and a two-source food web model

    Science.gov (United States)

    Søreide, Janne E.; Hop, Haakon; Carroll, Michael L.; Falk-Petersen, Stig; Hegseth, Else Nøst

    2006-10-01

    We simultaneously followed stable carbon ( δ13C) and nitrogen ( δ15N) isotopes in a two-source food web model to determine trophic levels and the relative importance of open water- and ice-associated food sources (phytoplankton vs. ice algae) in the lower marine food web in the European Arctic during four seasons. The model is based upon extensive seasonal data from 1995 to 2001. Phytoplankton, represented by samples of particulate organic matter from open water (Pelagic-POM) and ice algae, represented by samples from the underside of the ice (Ice-POM), were isotopically different. Ice-POM was generally dominated by the typical ice diatoms Nitzschia frigida and Melosira arctica and was more enriched than Pelagic-POM in 13C ( δ13C = -20‰ vs. -24‰), but less enriched in 15N ( δ15N = 1.8‰ vs. 4.0‰). However, when dominated by pelagic algae, Ice-POM was enriched in 13C and 15N similarly to Pelagic-POM. The derived trophic enrichment factors for δ15N (Δ N = 3.4‰) and δ13C (Δ C = 0.6‰) were similar in both pelagic and sympagic (ice-associated) systems, although the Δ C for the sympagic system was variable. Trophic level (TL) range for zooplankton (TL = 1.8-3.8) was similar to that of ice fauna (TL = 1.9-3.7), but ice amphipods were generally less enriched in δ15N than zooplankton, reflecting lower δ15N in Ice-POM compared to Pelagic-POM. For bulk zooplankton, TLs and carbon sources changed little seasonally, but the proportion of herbivores was higher during May-September than in October and March. Overall, we found that the primary carbon source for zooplankton was Pelagic-POM (mean 74%), but depending on species, season and TL, substantial carbon (up to 50%) was supplied from the sympagic system. For bulk ice fauna, no major changes were found in TLs or carbon sources from summer to autumn. The primary carbon source for ice fauna was Ice-POM (mean 67%), although ice fauna with TL > 3 (adult Onisimus nanseni and juvenile polar cod) primarily

  8. The shallow benthic food web structure in the high Arctic does not follow seasonal changes in the surrounding environment

    Science.gov (United States)

    Kędra, Monika; Kuliński, Karol; Walkusz, Wojciech; Legeżyńska, Joanna

    2012-12-01

    Seasonality, quality and quantity of food resources strongly affect fitness and survival of polar fauna. Most research conducted in polar areas has been carried out during the summer, rarely including aspects of seasonality; therefore, there are gaps in our knowledge of the structure of food webs in the Arctic, particularly information is lacking on the possible shifts in winter feeding strategies of organisms. This study is the first to compare potential shifts in benthic food-web structure between winter and summer in a shallow-water Arctic fjord (Kongsfjorden, Svalbard). Winter data were collected in March when conditions are representative of winter and when Arctic shallow benthic fauna is likely to be most affected by absence of fresh food supply as opposed to summer (August). Samples of particulate suspended organic matter (POM), settled organic matter, surface sediment and benthic organisms were taken and analyzed for stable isotopes signatures (δ13C and δ15N). Four relative trophic levels (TL) were distinguished in both winter and summer, and no differences in the structure of benthic food web were found between seasons. Our study shows that the shallow sublittoral benthos depends on primary production, fresh and reworked settled organic matter and, to a certain degree, on terrestrial input. We also demonstrate that shallow water polar benthic fauna is characterized by a high level of omnivory and feeds at multiple trophic levels showing strong resilience to changing seasonal conditions.

  9. Oceanic arsenic detoxication: the path of arsenic in marine food chains

    International Nuclear Information System (INIS)

    Arsenate appears to be readily metabolized by all marine algae. Its metabolism and mechanisms for biodegradation of the accumulated arsenolipids was investigated. The objective was to acquire sufficient understanding of the paths of arsenic in marine food chains to be able to evaluate the problems it might present to marine organisms and their effective productivity and the hazards its intermediates might present in marine products for human nutrition

  10. Arctic Watch

    Science.gov (United States)

    Orcutt, John; Baggeroer, Arthur; Mikhalevsky, Peter; Munk, Walter; Sagen, Hanne; Vernon, Frank; Worcester, Peter

    2015-04-01

    The dramatic reduction of sea ice in the Arctic Ocean will increase human activities in the coming years. This will be driven by increased demand for energy and the marine resources of an Arctic Ocean more accessible to ships. Oil and gas exploration, fisheries, mineral extraction, marine transportation, research and development, tourism and search and rescue will increase the pressure on the vulnerable Arctic environment. Synoptic in-situ year-round observational technologies are needed to monitor and forecast changes in the Arctic atmosphere-ice-ocean system at daily, seasonal, annual and decadal scales to inform and enable sustainable development and enforcement of international Arctic agreements and treaties, while protecting this critical environment. This paper will discuss multipurpose acoustic networks, including subsea cable components, in the Arctic. These networks provide communication, power, underwater and under-ice navigation, passive monitoring of ambient sound (ice, seismic, biologic and anthropogenic), and acoustic remote sensing (tomography and thermometry), supporting and complementing data collection from platforms, moorings and autonomous vehicles. This paper supports the development and implementation of regional to basin-wide acoustic networks as an integral component of a multidisciplinary, in situ Arctic Ocean Observatory.

  11. Radioactivity in the Arctic Seas. Report for the International Arctic Seas Assessment Project (IASAP)

    International Nuclear Information System (INIS)

    This report provides comprehensive information on environmental conditions in the Arctic Seas as required for the study of possible radiological consequences from dumped high level radioactive wastes in the Kara Sea. The report describes the oceanography of the regions, with emphasis on the Kara and Barents Seas, including the East Novaya Zemlya Fjords. The ecological description concentrates on biological production, marine food-weds and fisheries in the Arctic Seas. The report presents data on radionuclide concentrations in the Kara and Barents Seas and uses these data to estimate the inventories of radionuclides currently in the marine environment of the Kara and Barents Seas

  12. Biogenic carbon flows through the planktonic food web of the Amundsen Gulf (Arctic Ocean): A synthesis of field measurements and inverse modeling analyses

    Science.gov (United States)

    Forest, Alexandre; Tremblay, Jean-Éric; Gratton, Yves; Martin, Johannie; Gagnon, Jonathan; Darnis, Gérald; Sampei, Makoto; Fortier, Louis; Ardyna, Mathieu; Gosselin, Michel; Hattori, Hiroshi; Nguyen, Dan; Maranger, Roxane; Vaqué, Dolors; Marrasé, Cèlia; Pedrós-Alió, Carlos; Sallon, Amélie; Michel, Christine; Kellogg, Colleen; Deming, Jody; Shadwick, Elizabeth; Thomas, Helmuth; Link, Heike; Archambault, Philippe; Piepenburg, Dieter

    2011-12-01

    Major pathways of biogenic carbon (C) flow are resolved for the planktonic food web of the flaw lead polynya system of the Amundsen Gulf (southeast Beaufort Sea, Arctic Ocean) in spring-summer 2008. This period was relevant to study the effect of climate change on Arctic marine ecosystems as it was characterized by unusually low ice cover and warm sea surface temperature. Our synthesis relied on a mass balance estimate of gross primary production (GPP) of 52.5 ± 12.5 g C m -2 calculated using the drawdown of nitrate and dissolved inorganic C, and a seasonal f-ratio of 0.64. Based on chlorophyll a biomass, we estimated that GPP was dominated by phytoplankton (93.6%) over ice algae (6.4%) and by large cells (>5 μm, 67.6%) over small cells (functioning of the planktonic food web was elucidated through inverse analysis using the mean GPP and the 95% confidence limits of every other field measurement as lower and upper constraints. The model computed a net primary production of 49.2 g C m -2, which was directly channeled toward dominant calanoid copepods (i.e. Calanus hyperboreus 20%, Calanus glacialis 10%, and Metridia longa 10%), other mesozooplankton (12%), microzooplankton (14%), detrital POC (18%), and DOC (16%). Bacteria required 29.9 g C m -2, a demand met entirely by the DOC derived from local biological activities. The ultimate C outflow comprised respiration fluxes (82% of the initial GPP), a small sedimentation (3%), and a modest residual C flow (15%) resulting from NCP, dilution and accumulation. The sinking C flux at the model limit depth (395 m) supplied 60% of the estimated benthic C demand (2.8 g C m -2), suggesting that the benthos relied partly on other C sources within the bottom boundary layer to fuel its activity. In summary, our results illustrate that the ongoing decline in Arctic sea ice promotes the growth of pelagic communities in the Amundsen Gulf, which benefited from a ∼80% increase in GPP in spring-summer 2008 when compared to 2004 - a

  13. Geographical Area and Life History Traits Influence Diet in an Arctic Marine Predator.

    Directory of Open Access Journals (Sweden)

    Sabrina Tartu

    Full Text Available Global changes are thought to affect most Arctic species, yet some populations are more at risk. Today, the Barents Sea ecoregion is suffering the strongest sea ice retreat ever measured; and these changes are suspected to modify food access and thus diet of several species. Biochemical diet tracers enable investigation of diet in species such as polar bears (Ursus maritimus. We examined individual diet variation of female polar bears in Svalbard, Norway, and related it to year, season (spring and autumn, sampling area and breeding status (solitary, with cubs of the year or yearlings. Sampling areas were split according to their ice cover: North-West (less sea ice cover, South-East (larger amplitude in sea ice extent and North-East/South-West (NESW as bears from that zone are more mobile among all regions of Svalbard. We measured fatty acid (FA composition in adipose tissue and carbon (δ13C and nitrogen (δ15N stable isotopes in plasma and red blood cells. Females feeding in the North-West area had lower δ15N values than those from the NESW. In South-East females, δ13C values were lower in autumn compared to spring and females seemed less selective in their diet as depicted by large variances in stable isotope values. Considering the differences in FA composition and stable isotope values, we suggest that females from the North-West and South-East could ingest a higher proportion of avian prey. With regard to breeding status, solitary females had higher δ15N values and smaller variance in their stable isotopic values than females with cubs, suggesting that solitary females were more selective and prey on higher trophic level species (i.e. seals. Overall, our results indicate that prey availability for Svalbard polar bears varies according to geographical area and prey selectivity differs according to breeding status. Our findings suggest that complex changes in sea ice and prey availability will interact to affect Svalbard polar bear feeding

  14. Geographical Area and Life History Traits Influence Diet in an Arctic Marine Predator.

    Science.gov (United States)

    Tartu, Sabrina; Bourgeon, Sophie; Aars, Jon; Andersen, Magnus; Ehrich, Dorothee; Thiemann, Gregory W; Welker, Jeffrey M; Routti, Heli

    2016-01-01

    Global changes are thought to affect most Arctic species, yet some populations are more at risk. Today, the Barents Sea ecoregion is suffering the strongest sea ice retreat ever measured; and these changes are suspected to modify food access and thus diet of several species. Biochemical diet tracers enable investigation of diet in species such as polar bears (Ursus maritimus). We examined individual diet variation of female polar bears in Svalbard, Norway, and related it to year, season (spring and autumn), sampling area and breeding status (solitary, with cubs of the year or yearlings). Sampling areas were split according to their ice cover: North-West (less sea ice cover), South-East (larger amplitude in sea ice extent) and North-East/South-West (NESW) as bears from that zone are more mobile among all regions of Svalbard. We measured fatty acid (FA) composition in adipose tissue and carbon (δ13C) and nitrogen (δ15N) stable isotopes in plasma and red blood cells. Females feeding in the North-West area had lower δ15N values than those from the NESW. In South-East females, δ13C values were lower in autumn compared to spring and females seemed less selective in their diet as depicted by large variances in stable isotope values. Considering the differences in FA composition and stable isotope values, we suggest that females from the North-West and South-East could ingest a higher proportion of avian prey. With regard to breeding status, solitary females had higher δ15N values and smaller variance in their stable isotopic values than females with cubs, suggesting that solitary females were more selective and prey on higher trophic level species (i.e. seals). Overall, our results indicate that prey availability for Svalbard polar bears varies according to geographical area and prey selectivity differs according to breeding status. Our findings suggest that complex changes in sea ice and prey availability will interact to affect Svalbard polar bear feeding patterns

  15. Geographical Area and Life History Traits Influence Diet in an Arctic Marine Predator.

    Science.gov (United States)

    Tartu, Sabrina; Bourgeon, Sophie; Aars, Jon; Andersen, Magnus; Ehrich, Dorothee; Thiemann, Gregory W; Welker, Jeffrey M; Routti, Heli

    2016-01-01

    Global changes are thought to affect most Arctic species, yet some populations are more at risk. Today, the Barents Sea ecoregion is suffering the strongest sea ice retreat ever measured; and these changes are suspected to modify food access and thus diet of several species. Biochemical diet tracers enable investigation of diet in species such as polar bears (Ursus maritimus). We examined individual diet variation of female polar bears in Svalbard, Norway, and related it to year, season (spring and autumn), sampling area and breeding status (solitary, with cubs of the year or yearlings). Sampling areas were split according to their ice cover: North-West (less sea ice cover), South-East (larger amplitude in sea ice extent) and North-East/South-West (NESW) as bears from that zone are more mobile among all regions of Svalbard. We measured fatty acid (FA) composition in adipose tissue and carbon (δ13C) and nitrogen (δ15N) stable isotopes in plasma and red blood cells. Females feeding in the North-West area had lower δ15N values than those from the NESW. In South-East females, δ13C values were lower in autumn compared to spring and females seemed less selective in their diet as depicted by large variances in stable isotope values. Considering the differences in FA composition and stable isotope values, we suggest that females from the North-West and South-East could ingest a higher proportion of avian prey. With regard to breeding status, solitary females had higher δ15N values and smaller variance in their stable isotopic values than females with cubs, suggesting that solitary females were more selective and prey on higher trophic level species (i.e. seals). Overall, our results indicate that prey availability for Svalbard polar bears varies according to geographical area and prey selectivity differs according to breeding status. Our findings suggest that complex changes in sea ice and prey availability will interact to affect Svalbard polar bear feeding patterns

  16. Polonium ({sup 210}Po) and lead ({sup 210}Pb) in marine organisms and their transfer in marine food chains

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Fernando P., E-mail: carvalho@itn.p [Instituto Tecnologico e Nuclear, Departamento de Proteccao Radiologica e Seguranca Nuclear, E.N. 10, 2686-953 Sacavem (Portugal)

    2011-05-15

    The determination of {sup 210}Po and {sup 210}Pb was performed in marine organisms from the seashore to abyssal depths, encompassing a plethora of species from the microscopic plankton to the sperm whale. Concentrations of those radionuclides ranged from low values of about 5 x 10{sup -1} Bq kg{sup -1} (wet wt.) in jellyfish, to very high values of about of 3 x 10{sup 4} Bq kg{sup -1} (wet wt.) in the gut walls of sardines, with a common pattern of {sup 210}Po > {sup 210}Pb.These radionuclides are primarily absorbed from water and concentrated by phyto- and microzooplankton, and then are transferred to the next trophic level along marine food chains. Investigation in epipelagic, mesopelagic, bathypelagic and abyssobenthic organisms revealed that {sup 210}Po is transferred in the marine food webs with transfer factors ranging from 0.1 to 0.7, and numerically similar to those of the energy transfer in the marine food chains. As {sup 210}Po preferentially binds to amino acids and proteins, its transfer in food chains likely traces protein transfer and, thus, {sup 210}Po transfer factors are similar to ecotrophic coefficients. {sup 210}Pb is transferred less efficiently in marine food chains and this contributes to increased {sup 210}Po:{sup 210}Pb activity ratios in some trophic levels.

  17. Organic molecular composition of marine aerosols over the Arctic Ocean in summer: contributions of primary emission and secondary aerosol formation

    Directory of Open Access Journals (Sweden)

    P. Q. Fu

    2012-08-01

    Full Text Available Organic molecular composition of marine aerosol samples collected during the MALINA cruise in the Arctic Ocean was investigated by gas chromatography/mass spectrometry. More than 110 individual organic compounds were determined in the samples and were grouped into different compound classes based on the functionality and sources. The concentrations of total quantified organics ranged from 7.3 to 185 ng m−3 (mean 47.6 ng m−3, accounting for 1.8–11.0% (4.8% of organic carbon in the marine aerosols. Primary saccharides were found to be dominant organic compound class, followed by secondary organic aerosol (SOA tracers formed from the oxidation of biogenic volatile organic compounds (VOCs such as isoprene, α-pinene and β-caryophyllene. Mannitol, the specific tracer for airborne fungal spores, was detected as the most abundant organic species in the samples with a concentration range of 0.052–53.3 ng m−3 (9.2 ng m−3, followed by glucose, arabitol, and the isoprene oxidation products of 2-methyltetrols. Biomass burning tracers such as levoglucosan are evident in all samples with trace levels. On the basis of the tracer-based method for the estimation of fungal-spore OC and biogenic secondary organic carbon (SOC, we estimate that an average of 10.7% (up to 26.2% of the OC in the marine aerosols was due to the contribution of fungal spores, followed by the contribution of isoprene SOC (mean 3.8% and α-pinene SOC (2.9%. In contrast, only 0.19% of the OC was due to the photooxidation of β-caryophyllene. This study indicates that primary organic aerosols from biogenic emissions, both from long-range transport of mid-latitude aerosols and from sea-to-air emission of marine organics, as well as secondary organic aerosols formed from the photooxidation of biogenic VOCs are important factors controlling the organic chemical composition of marine aerosols in the Arctic Ocean.

  18. Organic molecular composition of marine aerosols over the Arctic Ocean in summer: contributions of primary emission and secondary aerosol formation

    Directory of Open Access Journals (Sweden)

    P. Q. Fu

    2013-02-01

    Full Text Available Organic molecular composition of marine aerosol samples collected during the MALINA cruise in the Arctic Ocean was investigated by gas chromatography/mass spectrometry. More than 110 individual organic compounds were determined in the samples and were grouped into different compound classes based on the functionality and sources. The concentrations of total quantified organics ranged from 7.3 to 185 ng m−3 (mean 47.6 ng m−3, accounting for 1.8–11.0% (4.8% of organic carbon in the marine aerosols. Primary saccharides were found to be dominant organic compound class, followed by secondary organic aerosol (SOA tracers formed from the oxidation of biogenic volatile organic compounds (VOCs such as isoprene, α-pinene and β-caryophyllene. Mannitol, the specific tracer for airborne fungal spores, was detected as the most abundant organic species in the samples with a concentration range of 0.052–53.3 ng m−3 (9.2 ng m−3, followed by glucose, arabitol, and the isoprene oxidation products of 2-methyltetrols. Biomass burning tracers such as levoglucosan are evident in all samples with trace levels. On the basis of the tracer-based method for the estimation of fungal-spore OC and biogenic secondary organic carbon (SOC, we estimate that an average of 10.7% (up to 26.2% of the OC in the marine aerosols was due to the contribution of fungal spores, followed by the contribution of isoprene SOC (mean 3.8% and α-pinene SOC (2.9%. In contrast, only 0.19% of the OC was due to the photooxidation of β-caryophyllene. This study indicates that primary organic aerosols from biogenic emissions, both from long-range transport of mid-latitude aerosols and from sea-to-air emission of marine organics, as well as secondary organic aerosols formed from the photooxidation of biogenic VOCs are important factors controlling the organic chemical composition of marine aerosols in the Arctic Ocean.

  19. Anthropogenic and natural radionuclides in caribou and muskoxen in the Western Alaskan Arctic and marine fish in the Aleutian Islands in the first half of 2000s

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Gi Hoon [Korea Ocean Research and Development Institute, 1270 Sa 2 dong, Ansan 426-744 (Korea, Republic of); Baskaran, Mark, E-mail: Baskaran@wayne.edu [Department of Geology, Wayne State University, Detroit, MI 48202 (United States); Molaroni, Shannon Marie [Department of Geology, Wayne State University, Detroit, MI 48202 (United States); Lee, Hyun-Mi [Korea Ocean Research and Development Institute, 1270 Sa 2 dong, Ansan 426-744 (Korea, Republic of); Burger, Joanna [Division of Life Sciences, 604 Allison Road, Rutgers University, Piscataway, NJ 08854-8082 (United States)

    2011-09-01

    A number of caribou and muskoxen samples from the western Alaskan Arctic and fish samples from the Aleutian Islands were collected between 1998 and 2006 and analyzed for anthropogenic ({sup 90}Sr and {sup 137}Cs) and natural radionculides ({sup 40} K, {sup 210}Pb and {sup 226}Ra), as part of the radiological assessment for the regional subsistence hunting communities in the first half of 2000s. We examined the relationship between the activities of these nuclides with the size of the fish. In caribou samples, concentration of {sup 90}Sr in muscle was below the detection limit of 0.14 Bq kg{sup -1} and {sup 137}Cs concentration in bones was below the detection limit of 0.15 Bq kg{sup -1}.{sup 137}Cs activity varied over an order of magnitude in caribou muscle samples with an average value of 2.5 Bq/kg wet wt. Average {sup 137}Cs activity in muskoxen muscle was found to be 9.7 Bq/kg wet wt. However, there were a little variation (less than 60%) in {sup 210}Pb, {sup 40} K, and {sup 226}Ra in both muscle and bone of both caribou and muskoxen. The activities of total {sup 210}Pb in caribou and muskox bones were found to be 1-2 orders of magnitude higher than that of parent-supported {sup 210}Pb indicating the potential for dating of bones of terrestrial mammals (time elapsed since the death of the animal) based on the excess {sup 210}Pb method exists. In fish muscle samples, {sup 137}Cs activity varied from below detection limit to 154 mBq/kg wet wt. and its content increased with the size of the fish due to its transfer through the food chain. Among the seven fish species investigated, {sup 210}Pb activities varied almost an order of magnitude; however, {sup 40}K and {sup 226}Ra activities varied less than a factor of two. Total annual effective dose due to {sup 90}Sr and {sup 137}Cs from the ingestion of those terrestrial and marine meats was estimated to be negligible (ca. 9 {mu}SV/a) compared to the natural radionuclides present thus posing negligible radiological

  20. Evolution of Arctic Ocean temperatures and fate of marine gas hydrates under global warming

    Science.gov (United States)

    Biastoch, Arne; Treude, Tina; Roth, Christina; Lüpke, Lars; Burwicz, Ewa; Park, Wonsun; Latif, Mojib; Böning, Claus; Madec, Gurvan; Wallmann, Klaus

    2010-05-01

    Several thousand gigatons of methane hydrates are estimated to be locked up in sediments of continental margins. Their stability is controlled by low temperature - high pressure conditions. Warming of the oceans could destabilize large amounts of hydrates along upper margins causing the release of methane, a greenhouse gas 30 times more potent per molecule than CO2, into the hydrosphere and atmosphere. The Arctic has considerably warmed during the recent decade, as witnessed by the rapid sea ice melt, and climate models project an acceleration of Arctic climate change in the future, if global greenhouse gas emissions continue to increase. Stabilized by year-round cold temperatures Arctic methane hydrates are deposited at shallow water depth close to shelf edges. Low pressure and the vicinity to the sea-air interface make Arctic gas hydrates more sensitive to atmospheric warming and associated changes in the temperature regime of the upper water masses compared to other oceans. We analyse bottom water temperatures and their future evolution projected by a climate model by applying a business as usual scenario and estimate their impact on the distribution of gas hydrate stability zones. Shallow gas hydrates are most strongly affected in areas affected by Atlantic inflow and could result in a significant impact on the methane distribution of the atmosphere, enhancing global warming

  1. Arctic Riverine CDOM and its effects on the Polar Marine Light Field

    Energy Technology Data Exchange (ETDEWEB)

    Orandle, Zoe Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Weijer, Wilbert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Elliott, Scott M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wang, Shanlin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-28

    It is well-known that CDOM (Chromophoric Dissolved Organic Matter) can have a significant effect on biological activity in the photic zones of aquatic ecosystems. However, the extent of CDOM’s interference with biological activity is not well-known. We examined this issue in great detail in the mixed surface layer of the Arctic Ocean. We studied the impacts of CDOM’s light attenuation on Arctic phytoplankton populations to discover if riverine CDOM’s presence in the Arctic ocean could inhibit and possibly prevent local phytoplankton populations from performing photosynthesis. We incorporated biogeochemistry concepts and data with oceanographic models and calculations to approach the problem. The results showed that riverine CDOM can indeed significantly impact the productivity of phytoplankton populations during the spring and summer months near the major Arctic river mouths we chose to examine. Although our study was detailed and inclusive of many variables, the issue of CDOM’s light attenuation and its effects on phytoplankton populations must be explored on a global scale to help understand if riverine CDOM could prove disastrous for phytoplankton populations.

  2. Arctic soil development on a series of marine terraces on central Spitsbergen, Svalbard: a combined geochronology, fieldwork and modelling approach

    Science.gov (United States)

    van der Meij, W. Marijn; Temme, Arnaud J. A. M.; de Kleijn, Christian M. F. J. J.; Reimann, Tony; Heuvelink, Gerard B. M.; Zwoliński, Zbigniew; Rachlewicz, Grzegorz; Rymer, Krzysztof; Sommer, Michael

    2016-06-01

    Soils in Arctic regions currently enjoy attention because of their sensitivity to climate change. It is therefore important to understand the natural processes and rates of development of these soils. Specifically, there is a need to quantify the rates and interactions between various landscape- and soil-forming processes. Soil chronosequences are ideal natural experiments for this purpose. In this contribution, we combine field observations, luminescence dating and soil-landscape modelling to improve and test our understanding of Arctic soil formation. The field site is a Holocene chronosequence of gravelly raised marine terraces in central Spitsbergen. Field observations show that soil-landscape development is mainly driven by weathering, silt translocation, aeolian deposition and rill erosion. Spatial soil variation is mainly caused by soil age, morphological position within a terrace and depth under the surface. Luminescence dating confirmed existing radiocarbon dating of the terraces, which are between ˜ 1.5 and ˜ 13.3 ka old. The soil-landscape evolution model LORICA was used to test our hypothesis that the field-observed processes indeed dominate soil-landscape development. Model results additionally indicated the importance of aeolian deposition as a source of fine material in the subsoil for both sheltered and vegetated trough positions and barren ridge positions. Simulated overland erosion was negligible. Consequently, an un-simulated process must be responsible for creating the observed erosion rills. Dissolution and physical weathering both play a major role. However, using present-day soil observations, the relative contribution of physical and chemical weathering could not be disentangled. Discrepancies between field and model results indicate that soil formation is non-linear and driven by spatially and temporally varying boundary conditions which were not included in the model. To conclude, Arctic soil and landscape development appears to be more

  3. Organochlorine pesticides and polychlorinated biphenyls in the Arctic Ocean food web.

    Science.gov (United States)

    Hargrave, B T; Harding, G C; Vass, W P; Erickson, P E; Fowler, B R; Scott, V

    1992-01-01

    ) reflects the metabolism of DDT to the more stable DDE isomers in amphipods. Metabolites of trans-chlordane were also measured in plankton and benthic amphipods. Although some OCs are degraded or metabolically transformed, accumulation in lipid-rich tissues results in the highest total concentrations in long-lived large-bodied arctic marine organisms. PMID:1554252

  4. Current-use pesticides in seawater and their bioaccumulation in polar bear-ringed seal food chains of the Canadian Arctic.

    Science.gov (United States)

    Morris, Adam D; Muir, Derek C G; Solomon, Keith R; Letcher, Robert J; McKinney, Melissa A; Fisk, Aaron T; McMeans, Bailey C; Tomy, Gregg T; Teixeira, Camilla; Wang, Xiaowa; Duric, Mark

    2016-07-01

    The distribution of current-use pesticides (CUPs) in seawater and their trophodynamics were investigated in 3 Canadian Arctic marine food chains. The greatest ranges of dissolved-phase concentrations in seawater for each CUP were endosulfan sulfate (less than method detection limit (MDL) to 19 pg L(-1) ) > dacthal (0.76-15 pg L(-1) ) > chlorpyrifos (less than MDL to 8.1 pg L(-1) ) > pentachloronitrobenzene (less than MDL to 2.6 pg L(-1) ) > α-endosulfan (0.20-2.3 pg L(-1) ). Bioaccumulation factors (BAFs, water-respiring organisms) were greatest in plankton, including chlorothalonil (log BAF = 7.4 ± 7.1 L kg(-1) , mean ± standard error), chlorpyrifos (log BAF = 6.9 ± 6.7 L kg(-1) ), and α-endosulfan (log BAF = 6.5 ± 6.0 L kg(-1) ). The largest biomagnification factors (BMFs) were found for dacthal in the capelin:plankton trophic relationship (BMF = 13 ± 5.0) at Cumberland Sound (Nunvavut), and for β-endosulfan (BMF = 16 ± 4.9) and α-endosulfan (BMF = 9.3 ± 2.8) in the polar bear-ringed seal relationship at Barrow and Rae Strait (NU), respectively. Concentrations of endosulfan sulfate exhibited trophic magnification (increasing concentrations with increasing trophic level) in the poikilothermic portion of the food web (trophic magnification factor = 1.4), but all of the CUPs underwent trophic dilution in the marine mammal food web, despite some trophic level-specific biomagnification. Together, these observations are most likely indicative of metabolism of these CUPs in mammals. Environ Toxicol Chem 2016;35:1695-1707. © 2016 SETAC. PMID:27027986

  5. Climate driven changes in hydrology, nutrient cycling, and food web dynamics in surface waters of the Arctic Coastal Plain, Alaska

    Science.gov (United States)

    Koch, J. C.; Wipfli, M.; Schmutz, J.; Gurney, K.

    2011-12-01

    Arctic ecosystems are changing rapidly as a result of a warming climate. While many areas of the arctic are expected to dry as a result of warming, the Arctic Coastal Plain (ACP) of Alaska, which extends from the Brooks Range north to the Beaufort Sea will likely become wetter, because subsurface hydrologic fluxes are constrained by thick, continuous permafrost. This landscape is characterized by large, oriented lakes and many smaller ponds that form in the low centers and troughs/edges of frost polygons. This region provides important breeding habitat for many migratory birds including loons, arctic terns, eiders, shorebirds, and white-fronted geese, among others. Increased hydrologic fluxes may provide a bottom-up control on the success of these species by altering the availability of food resources including invertebrates and fish. This work aimed to 1) characterize surface water fluxes and nutrient availability in the small streams and lake types of two study regions in the ACP, 2) predict how increased hydrological fluxes will affect the lakes, streams, and water chemistry, and 3) use nutrient additions to simulate likely changes in lake chemistry and invertebrate availability. Initial observations suggest that increasing wetland areas and availability of nutrients will result in increased invertebrate abundance, while the potential for drainage and terrestrialization of larger lakes may reduce fish abundance and overwintering habitat. These changes will likely have positive implications for insectivores and negative implications for piscivorous waterfowl.

  6. Assessing regional populations of ground-nesting marine birds in the Canadian High Arctic

    Directory of Open Access Journals (Sweden)

    Mark Maftei

    2015-04-01

    Full Text Available The Queens Channel region of Nunavut is an ecologically distinct area within the Canadian High Arctic consisting of an extensive archipelago of small, low-lying gravel islands throughout which form several localized but highly productive polynyas. We used aerial survey and colony-monitoring data to assess regional- and colony-level fluctuations in the number of birds in this region between 2002 and 2013. Regional and colony-specific monitoring suggested that common eider (Somateria mollissima numbers are increasing, while numbers of Arctic terns (Sterna paradisaea may be in decline. Based on these data, we suggest that even infrequent comprehensive surveys are more useful than annual monitoring at specific sites in generating an accurate assessment of ground-nesting seabird populations at the regional level, and that dramatic fluctuations at individual colonies probably belie the overall stability of regional populations.

  7. Antifungal activity of some marine organisms from India, against food spoilage Aspergillus strains

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosale, S.H.; Jagtap, T.G.; Naik, C.G.

    Crude aqueous methanol extracts obtained from 31 species of various marine organisms (including floral and faunal), were screened for their antifungal activity against food poisoning strains of Aspergillus. Seventeen species exhibited mild (+ = zone...

  8. Bacterial extracellular polymeric substances (EPS): A carrier of heavy metals in the marine food-chain

    Digital Repository Service at National Institute of Oceanography (India)

    Bhaskar, P.V.; Bhosle, N.B.

    The ecological implications of metal binding properties of bacterial EPS and its possible role in the bioaccumulation of pollutants in the marine food-chain was investigated using a partially purified and chemically characterized microbial EPS...

  9. Phylogenetic Diversity and Biological Activity of Actinobacteria Isolated from the Chukchi Shelf Marine Sediments in the Arctic Ocean

    Directory of Open Access Journals (Sweden)

    Meng Yuan

    2014-03-01

    Full Text Available Marine environments are a rich source of Actinobacteria and have the potential to produce a wide variety of biologically active secondary metabolites. In this study, we used four selective isolation media to culture Actinobacteria from the sediments collected from the Chukchi Shelf in the Arctic Ocean. A total of 73 actinobacterial strains were isolated. Based on repetitive DNA fingerprinting analysis, we selected 30 representatives for partial characterization according to their phylogenetic diversity, antimicrobial activities and secondary-metabolite biosynthesis genes. Results from the 16S rRNA gene sequence analysis indicated that the 30 strains could be sorted into 18 phylotypes belonging to 14 different genera: Agrococcus, Arsenicicoccus, Arthrobacter, Brevibacterium, Citricoccus, Janibacter, Kocuria, Microbacterium, Microlunatus, Nocardioides, Nocardiopsis, Saccharopolyspora, Salinibacterium and Streptomyces. To our knowledge, this paper is the first report on the isolation of Microlunatus genus members from marine habitats. Of the 30 isolates, 11 strains exhibited antibacterial and/or antifungal activity, seven of which have activities against Bacillus subtilis and Candida albicans. All 30 strains have at least two biosynthetic genes, one-third of which possess more than four biosynthetic genes. This study demonstrates the significant diversity of Actinobacteria in the Chukchi Shelf sediment and their potential for producing biologically active compounds and novel material for genetic manipulation or combinatorial biosynthesis.

  10. Phylogenetic diversity and biological activity of actinobacteria isolated from the Chukchi Shelf marine sediments in the Arctic Ocean.

    Science.gov (United States)

    Yuan, Meng; Yu, Yong; Li, Hui-Rong; Dong, Ning; Zhang, Xiao-Hua

    2014-03-01

    Marine environments are a rich source of Actinobacteria and have the potential to produce a wide variety of biologically active secondary metabolites. In this study, we used four selective isolation media to culture Actinobacteria from the sediments collected from the Chukchi Shelf in the Arctic Ocean. A total of 73 actinobacterial strains were isolated. Based on repetitive DNA fingerprinting analysis, we selected 30 representatives for partial characterization according to their phylogenetic diversity, antimicrobial activities and secondary-metabolite biosynthesis genes. Results from the 16S rRNA gene sequence analysis indicated that the 30 strains could be sorted into 18 phylotypes belonging to 14 different genera: Agrococcus, Arsenicicoccus, Arthrobacter, Brevibacterium, Citricoccus, Janibacter, Kocuria, Microbacterium, Microlunatus, Nocardioides, Nocardiopsis, Saccharopolyspora, Salinibacterium and Streptomyces. To our knowledge, this paper is the first report on the isolation of Microlunatus genus members from marine habitats. Of the 30 isolates, 11 strains exhibited antibacterial and/or antifungal activity, seven of which have activities against Bacillus subtilis and Candida albicans. All 30 strains have at least two biosynthetic genes, one-third of which possess more than four biosynthetic genes. This study demonstrates the significant diversity of Actinobacteria in the Chukchi Shelf sediment and their potential for producing biologically active compounds and novel material for genetic manipulation or combinatorial biosynthesis. PMID:24663116

  11. Mercury bioaccumulation and biomagnification in a small Arctic polynya ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Clayden, Meredith G., E-mail: meredith.clayden@gmail.com [Canadian Rivers Institute and Biology Department, University of New Brunswick, Saint John, NB E2L 4L5 (Canada); Arsenault, Lilianne M. [Canadian Rivers Institute and Biology Department, University of New Brunswick, Saint John, NB E2L 4L5 (Canada); Department of Earth and Environmental Science, Acadia University, Wolfville, NS B4P 2R6 (Canada); Department of Biology, Acadia University, Wolfville, NS B4P 2R6 (Canada); Kidd, Karen A. [Canadian Rivers Institute and Biology Department, University of New Brunswick, Saint John, NB E2L 4L5 (Canada); O' Driscoll, Nelson J. [Department of Earth and Environmental Science, Acadia University, Wolfville, NS B4P 2R6 (Canada); Mallory, Mark L. [Department of Biology, Acadia University, Wolfville, NS B4P 2R6 (Canada)

    2015-03-15

    Recurring polynyas are important areas of biological productivity and feeding grounds for seabirds and mammals in the Arctic marine environment. In this study, we examined food web structure (using carbon and nitrogen isotopes, δ{sup 13}C and δ{sup 15}N) and mercury (Hg) bioaccumulation and biomagnification in a small recurring polynya ecosystem near Nasaruvaalik Island (Nunavut, Canada). Methyl Hg (MeHg) concentrations increased by more than 50-fold from copepods (Calanus hyperboreus) to Arctic terns (Sterna paradisaea), the abundant predators at this site. The biomagnification of MeHg through members of the food web – using the slope of log MeHg versus δ{sup 15}N – was 0.157 from copepods (C. hyperboreus) to fish. This slope was higher (0.267) when seabird chicks were included in the analyses. Collectively, our results indicate that MeHg biomagnification is occurring in this small polynya and that its trophic transfer is at the lower end of the range of estimates from other Arctic marine ecosystems. In addition, we measured Hg concentrations in some poorly studied members of Arctic marine food webs [e.g. Arctic alligatorfish (Ulcina olrikii) and jellyfish, Medusozoa], and found that MeHg concentrations in jellyfish were lower than expected given their trophic position. Overall, these findings provide fundamental information about food web structure and mercury contamination in a small Arctic polynya, which will inform future research in such ecosystems and provide a baseline against which to assess changes over time resulting from environmental disturbance. - Highlights: • Polynyas are recurring sites of open water in polar marine areas • Mercury (Hg) biomagnification was studied in a small polynya near Nasaruvaalik Island, NU, Canada • Hg biomagnification estimates for invertebrates to fish were low compared to other Arctic systems • Factors underlying this result are unknown but may relate to primary productivity in small polynyas.

  12. Mercury bioaccumulation and biomagnification in a small Arctic polynya ecosystem

    International Nuclear Information System (INIS)

    Recurring polynyas are important areas of biological productivity and feeding grounds for seabirds and mammals in the Arctic marine environment. In this study, we examined food web structure (using carbon and nitrogen isotopes, δ13C and δ15N) and mercury (Hg) bioaccumulation and biomagnification in a small recurring polynya ecosystem near Nasaruvaalik Island (Nunavut, Canada). Methyl Hg (MeHg) concentrations increased by more than 50-fold from copepods (Calanus hyperboreus) to Arctic terns (Sterna paradisaea), the abundant predators at this site. The biomagnification of MeHg through members of the food web – using the slope of log MeHg versus δ15N – was 0.157 from copepods (C. hyperboreus) to fish. This slope was higher (0.267) when seabird chicks were included in the analyses. Collectively, our results indicate that MeHg biomagnification is occurring in this small polynya and that its trophic transfer is at the lower end of the range of estimates from other Arctic marine ecosystems. In addition, we measured Hg concentrations in some poorly studied members of Arctic marine food webs [e.g. Arctic alligatorfish (Ulcina olrikii) and jellyfish, Medusozoa], and found that MeHg concentrations in jellyfish were lower than expected given their trophic position. Overall, these findings provide fundamental information about food web structure and mercury contamination in a small Arctic polynya, which will inform future research in such ecosystems and provide a baseline against which to assess changes over time resulting from environmental disturbance. - Highlights: • Polynyas are recurring sites of open water in polar marine areas • Mercury (Hg) biomagnification was studied in a small polynya near Nasaruvaalik Island, NU, Canada • Hg biomagnification estimates for invertebrates to fish were low compared to other Arctic systems • Factors underlying this result are unknown but may relate to primary productivity in small polynyas

  13. Food and water security issues in Russia III: food- and waterborne diseases in the Russian Arctic, Siberia and the Far East, 2000–2011

    Directory of Open Access Journals (Sweden)

    Alexey A. Dudarev

    2013-12-01

    Full Text Available Background . The food- and waterborne disease situation in Russia requires special attention. Poor quality of centralized water supplies and sewage systems, biological and chemical contamination of drinking water, as well as contamination of food products, promote widespread infectious diseases, significantly exceeding nationwide rates in the population living in the two-thirds of Russian northern territories. Objectives. The general aim was to assess the levels of food- and waterborne diseases in selected regions of Russian Arctic, Siberia and the Far East (for the period 2000–2011, and to compare disease levels among regions and with national levels in Russia. Study design and methods . This study is the first comparative assessment of the morbidity in these fields of the population of 18 selected regions of Russian Arctic, Siberia and the Far East, using official statistical sources. The incidences of infectious and parasitic food- and waterborne diseases among the general population (including indigenous peoples have been analyzed in selected regions (per 100,000 of population, averaged for 2000–2011. Results . Among compulsory registered infectious and parasitic diseases, there were high rates and widespread incidences in selected regions of shigellosis, yersiniosis, hepatitis A, tularaemia, giardiasis, enterobiasis, ascariasis, diphyllobothriasis, opistorchiasis, echinococcosis and trichinellosis. Conclusion . Incidences of infectious and parasitic food- and waterborne diseases in the general population of selected regions of the Russian Arctic, Siberia and the Far East (2000–2011 are alarmingly high. Parallel solutions must be on the agenda, including improvement of sanitary conditions of cities and settlements in the regions, modernization of the water supply and of the sewage system. Provision and monitoring of the quality of the drinking water, a reform of the general healthcare system and the epidemiological surveillance

  14. Zinc isotope ratios as indicators of diet and trophic level in Arctic marine mammals

    OpenAIRE

    Klervia Jaouen; Paul Szpak; Richards, Michael P.

    2016-01-01

    Carbon and nitrogen stable isotope ratios of bone collagen are an established method for dietary reconstruction, but this method is limited by the protein preservation. Zinc (Zn) is found in bioapatite and the isotopic compositions of this element constitute a very promising dietary indicator. The extent of fractionation of Zn isotopes in marine environments, however, remains unknown. We report here on the measurement of zinc, carbon and nitrogen isotopes in 47 marine mammals from the archaeo...

  15. Impacts of decline harvest of country food on nutrient intake among Inuit in Arctic Canada: impact of climate change and possible adaptation plan

    OpenAIRE

    Rosol, Renata; Powell-Hellyer, Stephanie; Chan, Hing Man

    2016-01-01

    Background. The pervasive food insecurity and the diet transition away from local, nutrient-rich country foods present a public health challenge among Inuit living in the Canadian Arctic. While environmental factors such as climate change decreased the accessibility and availability of many country food species, new species were introduced into regions where they were previously unavailable. An adaptation such as turning to alternate country food species can be a viable solution to substitute...

  16. Building upon cooperative prospects amongst stakeholders for fighting Arctic marine invasion challenges

    DEFF Research Database (Denmark)

    Kourantidou, Melina; Kaiser, Brooks; Fernandez, Linda;

    expect that game theoretic environmental economic tools can help illuminate aspects of invasive species management significant for sound decision-making processes. Building blocks of such a game theoretic approach include the different players (stakeholders) involved. In our case study, we take...... into account the existing different management practices (for RKC) and the different market interests (based on consumer demand and fishing industry effort) as well as the ecosystem itself. At a minimum the following stakeholders have interdependent payoffs affecting not only the human actors but also...... in the decision making process to help articulate incentive-compatible ecosystem management strategies that are adaptive to new information garnered from sustained Arctic observations....

  17. Distribution of branched GDGTs in surface sediments from the Colville River, Alaska: Implications for the MBT'/CBT paleothermometer in Arctic marine sediments

    Science.gov (United States)

    Hanna, Andrea J. M.; Shanahan, Timothy M.; Allison, Mead A.

    2016-07-01

    Significant climate fluctuations in the Arctic over the recent past, and additional predicted future temperature changes, highlight the need for high-resolution Arctic paleoclimate records. Arctic coastal environments supplied with terrigenous sediment from Arctic rivers have the potential to provide annual to subdecadal resolution records of climate variability over the last few millennia. A potential tool for paleotemperature reconstructions in these marine sediments is the revised methylation index of branched tetraethers (MBT')/cyclization ratio of branched tetraethers (CBT) proxy based on branched glycerol dialkyl glycerol tetraethers (brGDGTs). In this study, we examine the source of brGDGTs in the Colville River, Alaska, and the adjacent Simpson Lagoon and reconstruct temperatures from Simpson Lagoon sediments to evaluate the applicability of this proxy in Arctic estuarine environments. The Colville catchment soils, fluvial sediments, and estuarine sediments contain statistically similar brGDGT distributions, indicating that the brGDGTs throughout the system are soil derived with little alteration from in situ brGDGT production in the river or coastal waters. Temperatures reconstructed from the MBT'/CBT indices for surface samples show good agreement with regional summer (June through September) temperatures, suggesting a seasonal bias in Arctic temperature reconstructions from the Colville system. In addition, we reconstruct paleotemperatures from an estuarine sediment core that spans the last 75 years, revealing an overall warming trend in the twentieth century that is consistent with trends observed in regional instrumental records. These results support the application of this brGDGT-based paleotemperature proxy for subdecadal-scale summer temperature reconstructions in Arctic estuaries containing organic material derived from sediment-laden, episodic rivers.

  18. Marine-Based Nutraceuticals: An Innovative Trend in the Food and Supplement Industries.

    Science.gov (United States)

    Suleria, Hafiz Ansar Rasul; Osborne, Simone; Masci, Paul; Gobe, Glenda

    2015-10-01

    Recent trends in functional foods and supplements have demonstrated that bioactive molecules play a major therapeutic role in human disease. Nutritionists and biomedical and food scientists are working together to discover new bioactive molecules that have increased potency and therapeutic benefits. Marine life constitutes almost 80% of the world biota with thousands of bioactive compounds and secondary metabolites derived from marine invertebrates such as tunicates, sponges, molluscs, bryozoans, sea slugs and many other marine organisms. These bioactive molecules and secondary metabolites possess antibiotic, antiparasitic, antiviral, anti-inflammatory, antifibrotic and anticancer activities. They are also inhibitors or activators of critical enzymes and transcription factors, competitors of transporters and sequestrants that modulate various physiological pathways. The current review summaries the widely available marine-based nutraceuticals and recent research carried out for the purposes of isolation, identification and characterization of marine-derived bioactive compounds with various therapeutic potentials. PMID:26473889

  19. Contaminants in food chains of arctic ungulates: what have we learned from the Chernobyl accident?

    Directory of Open Access Journals (Sweden)

    Birgitta Åhman

    1998-03-01

    Full Text Available The Chernobyl accidenr of 1986 caused radioactive contamination of widespread areas of reindeer pasture in Scandinavia. Reindeer {Rangifer tarandus are especially exposed to radioactive fallout due to their wintet diet, of which lichens are an important part. Much knowledge about the transfer of radiocaesium to reindeer, and via reindeer meat to man, was accumulated by intense scientific investigations, undertaken during the 1960s and 1970s, following nuclear weapons testing. Various ways to reduce the transfer of radiocaesium to animals and humans were also developed during this time. Much of the older knowledge proved to be of great value in the attempts to determine potential consequences of the Chernobyl accident and to suggest possible ways to ameliorate the effects of contamination. After Chernobyl, not only did reindeer prove to be a problem; many other food products originating ftom natural and semi-natural ecosystems were found to accumulate significant amounts of radiocaesium. Intense scientific work has produced new knowledge about the role of ungulates in the transfer of nutrients and contaminants within these systems. Different measures, like providing uncontaminated feed, use of caesium binders, altering the time of slaughter have been used with good results to minimize the transfer of radiocaesium to animals grazing natural pastures. The high cost of countermeasures has enforced consideration of cost against risk, which may also be of general interest with respect to other forms of pollution. Information, introduction of countermeasures and so forth would be more efficient in case a similar accident were to happen again. The Chernobyl accident is an obvious example of how human failures when dealing with a modern technical system can have global consequences and also be a potential threat to what we like to think of as the unspoiled wilderness of the Arctic.

  20. Contaminants in food chains of arctic ungulates: what have we learned from the Chernobyl accident?

    International Nuclear Information System (INIS)

    The Chernobyl accident of 1986 caused radioactive contamination of widespread areas of reindeer pasture in Scandinavia. Reindeer (Rangifer tarandus) are especially exposed to radioactive fallout due to their winter diet, of which lichens are an important part. Much knowledge about the transfer of radiocaesium to reindeer, and via reindeer meat to man, was accumulated by intense scientific investigations, undertaken during the 1960s and 1970s, following nuclear weapons testing. Various ways to reduce the transfer of radiocaesium to animals and humans were also developed during this time. Much of the older knowledge proved to be of great value in the attempts to determine potential consequences of the Chernobyl accident and to suggest possible ways to ameliorate the effects of contamination. After Chernobyl, not only did reindeer prove to be a problem; many other food products originating from natural and semi-natural ecosystems were found to accumulate significant amounts of radiocaesium. Intense scientific work has produced new knowledge about the role of ungulates in the transfer of nutrients and contaminants within these systems. Different measures, like providing uncontaminated feed, use of caesium binders, altering the time of slaughter have been used with good results to minimize the transfer of radiocaesium to animals grazing natural pastures. The high cost of countermeasures has enforced consideration of cost against risk, which may also be of general interest with respect to other forms of pollution. Information, introduction of countermeasures and so forth would be more efficient in case a similar accident were to happen again. The Chernobyl accident is an obvious example of how human failures when dealing with a modern technical system can have global consequences and also be a potential threat to what we like to think of as the unspoiled wilderness of the Arctic

  1. Soil and Freshwater and Marine Sediment Food Webs: Their Structure and Function

    NARCIS (Netherlands)

    Adams Krumins, J.; van Oevelen, D.; Bezemer, T.M.; de Deyn, G.B.; Hol, W.H.G.; van Donk, E.; de Boer, W.; de Ruiter, P.C.; Middelburg, J.J.; Monroy, F.; Soetaert, K.; Thébault, E.; van de Koppel, J.; van Veen, J.A.; Viketoft, M.; van der Putten, W.H.

    2013-01-01

    The food webs of terrestrial soils and of freshwater and marine sediments depend on adjacent aboveground or pelagic ecosystems for organic matter input that provides nutrients and energy. There are important similarities in the flow of organic matter through these food webs and how this flow feeds b

  2. Beyond Thin Ice: Co-Communicating the Many Arctics

    Science.gov (United States)

    Druckenmiller, M. L.; Francis, J. A.; Huntington, H.

    2015-12-01

    Science communication, typically defined as informing non-expert communities of societally relevant science, is persuaded by the magnitude and pace of scientific discoveries, as well as the urgency of societal issues wherein science may inform decisions. Perhaps nowhere is the connection between these facets stronger than in the marine and coastal Arctic where environmental change is driving advancements in our understanding of natural and socio-ecological systems while paving the way for a new assortment of arctic stakeholders, who generally lack adequate operational knowledge. As such, the Arctic provides opportunity to advance the role of science communication into a collaborative process of engagement and co-communication. To date, the communication of arctic change falls within four primary genres, each with particular audiences in mind. The New Arctic communicates an arctic of new stakeholders scampering to take advantage of unprecedented access. The Global Arctic conveys the Arctic's importance to the rest of the world, primarily as a regulator of lower-latitude climate and weather. The Intra-connected Arctic emphasizes the increasing awareness of the interplay between system components, such as between sea ice loss and marine food webs. The Transforming Arctic communicates the region's trajectory relative to the historical Arctic, acknowledging the impacts on indigenous peoples. The broad societal consensus on climate change in the Arctic as compared to other regions in the world underscores the opportunity for co-communication. Seizing this opportunity requires the science community's engagement with stakeholders and indigenous peoples to construct environmental change narratives that are meaningful to climate responses relative to non-ecological priorities (e.g., infrastructure, food availability, employment, or language). Co-communication fosters opportunities for new methods of and audiences for communication, the co-production of new interdisciplinary

  3. Assessing the effect of marine reserves on household food security in Kenyan coral reef fishing communities.

    Directory of Open Access Journals (Sweden)

    Emily S Darling

    Full Text Available Measuring the success or failure of natural resource management is a key challenge to evaluate the impact of conservation for ecological, economic and social outcomes. Marine reserves are a popular tool for managing coastal ecosystems and resources yet surprisingly few studies have quantified the social-economic impacts of marine reserves on food security despite the critical importance of this outcome for fisheries management in developing countries. Here, I conducted semi-structured household surveys with 113 women heads-of-households to investigate the influence of two old, well-enforced, no-take marine reserves on food security in four coastal fishing communities in Kenya, East Africa. Multi-model information-theoretic inference and matching methods found that marine reserves did not influence household food security, as measured by protein consumption, diet diversity and food coping strategies. Instead, food security was strongly influenced by fishing livelihoods and household wealth: fishing families and wealthier households were more food secure than non-fishing and poorer households. These findings highlight the importance of complex social and economic landscapes of livelihoods, urbanization, power and gender dynamics that can drive the outcomes of marine conservation and management.

  4. The Influence of Processing on the DNA Integrity in Several Raw Materials of Marine Foods

    Directory of Open Access Journals (Sweden)

    Yuan Xiao

    2015-03-01

    Full Text Available With the development of molecular biotechnology, methods for identification of marine food are developed from protein to DNA. The experimental materials are striped bass, Sturgeon and mandarin fish. They were processed with boiling, salting and microwave-heating methods. DNA-based research has been conducted in almost every corner in food material identification. This study is mainly about the identification methods of distinguishing processed aquatic products and the influence of processing on the DNA integrity in the raw materials of marine foods.

  5. Wintertime Arctic Ocean sea water properties and primary marine aerosol concentrations

    Directory of Open Access Journals (Sweden)

    J. Zábori

    2012-11-01

    Full Text Available Sea spray aerosols are an important part of the climate system through their direct and indirect effects. Due to the diminishing sea ice, the Arctic Ocean is one of the most rapidly changing sea spray aerosol source areas. However, the influence of these changes on primary particle production is not known.

    In laboratory experiments we examined the influence of Arctic Ocean water temperature, salinity, and oxygen saturation on primary particle concentration characteristics. Sea water temperature was identified as the most important of these parameters. A strong decrease in sea spray aerosol production with increasing water temperature was observed for water temperatures between −1°C and 9°C. Aerosol number concentrations decreased from at least 1400 cm−3 to 350 cm−3. In general, the aerosol number size distribution exhibited a robust shape with one mode close to dry diameter Dp 0.2 μm with approximately 45% of particles at smaller sizes. Changes in sea water temperature did not result in pronounced change of the shape of the aerosol size distribution, only in the magnitude of the concentrations. Our experiments indicate that changes in aerosol emissions are most likely linked to changes of the physical properties of sea water at low temperatures. The observed strong dependence of sea spray aerosol concentrations on sea water temperature, with a large fraction of the emitted particles in the typical cloud condensation nuclei size range, provide strong arguments for a more careful consideration of this effect in climate models.

  6. Assessment of consumption of marine food in Greenland by a food frequency questionnaire and biomarkers

    Directory of Open Access Journals (Sweden)

    Charlotte Jeppesen

    2012-05-01

    Full Text Available Objectives. We studied the association and agreement between questionnaire data and biomarkers of marine food among Greenland Inuit. Design. Cross sectional study. Methods. The study population comprised 2,224 Inuit, age 18+ (43% men; data collected 2005–2008 in Greenland. Using a food frequency questionnaire (FFQ, we calculated consumption of seal, whale, and fish (g/day and as meals/month, intake of eicosapentaenoic acid (EPA, docosahexaenoic acid (DHA, total N3, and mercury. We measured erythrocyte membrane fatty acids (FA and whole blood mercury (Hg. Associations were assessed by Pearson correlation and agreement between the 2 methods was assessed by Bland–Altman plots depicting mean difference between the methods. Using multiple linear regressions, the associations were studied between whole blood mercury, erythrocyte FA and frequency or gram per day of seal, whale, and fish. Results. Partial correlations ranged from r=0.16, p<0.0001 (DHA to r=0.56, p<0.0001 (mercury. The best fitted lines were found for mercury and DHA. Mean difference was negative for mercury but positive for all the FA biomarkers. In a multiple logistic regression analysis, the best association was found between whole blood mercury and seal consumption, both as frequency in meals and actual intake gram per day: β=1.07 µg (95% CI: 1.06; 1.08 and β=1.04 µg (95% CI: 1.03; 1.04, respectively. Conclusion. Mercury showed the best correlation and agreement between calculated and measured values. Calculated actual intake in gram per day and frequency of meals showed similar associations with whole blood mercury and erythrocyte membrane FAs.

  7. Trace elements and cathodoluminescence of detrital quartz in Arctic marine sediments – a new ice-rafted debris provenance proxy

    Directory of Open Access Journals (Sweden)

    A. Müller

    2013-07-01

    Full Text Available The records of ice-rafted debris (IRD provenance in the North Atlantic – Barents Sea allow the reconstruction of the spatial and temporal changes of ice-flow drainage patterns during glacial and deglacial periods. In this study a new approach to characterisation of the provenance of detrital quartz grains in the fraction > 500 μm of marine sediments offshore of Spitsbergen is introduced, utilizing scanning electron microscope backscattered electron and cathodoluminescence (CL imaging, combined with laser ablation inductively-coupled plasma mass spectrometry. Based on their micro-inclusions, CL and trace element characteristics the investigated IRD grains can be classified into five distinct populations. Three of the populations are indicative of potential IRD provenance provinces in the Storfjord area including Barentsøya and Egdeøya. The results imply that under modern (interglacial conditions IRD deposition along the western Spitsbergen margin is mainly governed by the East Svalbard Current controlling the ice-drift pattern. The presence of detrital quartz from local provinces, however, indicates that variations in IRD supply from western Spitsbergen may be quantified as well. In this pilot study it is demonstrated that this new approach applied on Arctic continental margin sediments, bears a considerable potential for the definition of the sources of IRD and thus of spatial/temporal changes in ice-flow drainage patterns during glacial/interglacial cycles.

  8. Parasites as biological tags of marine, freshwater and anadromous fishes in North America from the Tropics to the Arctic.

    Science.gov (United States)

    Marcogliese, David J; Jacobson, Kym C

    2015-01-01

    Parasites have been considered as natural biological tags of marine fish populations in North America for almost 75 years. In the Northwest Atlantic, the most studied species include Atlantic cod (Gadus morhua), Atlantic herring (Clupea harengus) and the redfishes (Sebastes spp.). In the North Pacific, research has centred primarily on salmonids (Oncorhynchus spp.). However, parasites have been applied as tags for numerous other pelagic and demersal species on both the Atlantic and Pacific coasts. Relatively few studies have been undertaken in the Arctic, and these were designed to discriminate anadromous and resident salmonids (Salvelinus spp.). Although rarely applied in fresh waters, parasites have been used to delineate certain fish stocks within the Great Lakes-St Lawrence River basin. Anisakid nematodes and the copepod Sphyrion lumpi frequently prove useful indicators in the Northwest Atlantic, while myxozoan parasites prove very effective on the coast and open seas of the Pacific Ocean. Relative differences in the ability of parasites to discriminate between fish stocks on the Pacific and Atlantic coasts may be due to oceanographic and bathymetric differences between regions. Molecular techniques used to differentiate populations and species of parasites show promise in future applications in the field.

  9. Marine Bioactives as Functional Food Ingredients: Potential to Reduce the Incidence of Chronic Diseases

    Directory of Open Access Journals (Sweden)

    Catherine Stanton

    2011-06-01

    Full Text Available The marine environment represents a relatively untapped source of functional ingredients that can be applied to various aspects of food processing, storage, and fortification. Moreover, numerous marine-based compounds have been identified as having diverse biological activities, with some reported to interfere with the pathogenesis of diseases. Bioactive peptides isolated from fish protein hydrolysates as well as algal fucans, galactans and alginates have been shown to possess anticoagulant, anticancer and hypocholesterolemic activities. Additionally, fish oils and marine bacteria are excellent sources of omega-3 fatty acids, while crustaceans and seaweeds contain powerful antioxidants such as carotenoids and phenolic compounds. On the basis of their bioactive properties, this review focuses on the potential use of marine-derived compounds as functional food ingredients for health maintenance and the prevention of chronic diseases.

  10. The Content of Fat and Polyenoic Acids in the Major Food Sources of the Arctic Diet

    DEFF Research Database (Denmark)

    Shukla, V. K. S.; Clausen, Jytte Lene; Egsgaard, Helge;

    1980-01-01

    In relation to the apparently low incidence of coronary heart diseases in Arctic populations the fatty acid pattern of muscle and fat tissue of the Arctic seal, birds and mammals were compared with the fatty acid pattern of the corresponding tissues of domestic animals normally used as meat sources...... in western countries. The triglyceride content of muscle samples was also estimated. A gas chromatography-mass spectrometry system was used for localizing the position of double bonds in the unsaturated acids, by means of their pyrrolidides. The fat tissue from the seal was the main source of polyenoic acids....... The fat content of muscle tissue in Arctic animals was not less than that of domestic meat....

  11. Isolation and characterization of a marine bacterium producing protease from Chukchi Sea, Arctic

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A Gram negative bacterium Ar/W/b/75°25'N/1 producing extracellular alkaline protease was isolated from surface water of latitude 75°25'N, and longitude 162°25'W in Chukchi sea, Arctic. The strain can grow at the temperature range from 7℃ to 30℃, and grow better at 30(℃. It can not grow at 40℃. Keeping certain salinity concentration in medium is necessary for cell growth. It grows well in medium containing salinity concentration from 0. 5 % to 10 % sodium chloride. Glucose, sucrose and soluble starch can be utilized by the strain, among which glucose is the optimal carbon source. Peptone is the optimal organic nitrogen source for cell growth and protease producing, and ammonium nitrate is the optimal inorganic nitrogen source.About 75.7% of total protease of the strain are extracellular enzyme. Optimal temperature for proteolytic activity is at 40℃. Protease of the strain keeps stable below 40℃, and shows high proteolytic activity within the pH range from 7 to 11.

  12. Technical Note: Constraining stable carbon isotope values of microphytobenthos (C3 photosynthesis) in the Arctic for application to food web studies

    Science.gov (United States)

    Oxtoby, L. E.; Mathis, J. T.; Juranek, L. W.; Wooller, M. J.

    2013-11-01

    Microphytobenthos (MPB) tends to be omitted as a possible carbon source to higher trophic level consumers in high latitude marine food web models that use stable isotopes. Here, we used previously published relationships relating the concentration of aqueous carbon dioxide ([CO2]aq), the stable carbon isotopic composition of dissolved inorganic carbon (DIC) (δ13CDIC), and algal growth rates (μ) to estimate the stable carbon isotope composition of MPB-derived total organic carbon (TOC) (δ13Cp) and fatty acid (FA) biomarkers (δ13CFA). We measured [CO2]aq and δ13CDIC values from bottom water at sampling locations in the Beaufort and Chukchi Seas (n = 18), which ranged from 17 to 72 mmol kg-1 and -0.1 to 1.4 ‰ (0.8 ± 0.4‰, mean ±1 s.d.), respectively. We combined these field measurements with a set of stable carbon isotopic fractionation factors reflecting differences in algal taxonomy and physiology to determine δ13Cp and δ13CFA values. Theδ13Cp and δ13CFA values for a mixed eukaryotic algal community were estimated to be -23.6 ± 0.4‰ and -30.6 ± 0.4‰, respectively. These values were similar to our estimates for Phaeodactylum tricornutum (δ13Cp = -23.9 ± 0.4‰, δ13CFA = -30.9 ± 0.4‰), a pennate diatom likely to be a dominant MPB taxon. Taxon-specific differences were observed between a centric diatom (Porosira glacialis, δ13Cp = -20.0 ± 1.6‰), a marine haptophyte (Emiliana huxleyi, δ13Cp = -22.7 ± 0.5‰), and a cyanobacterium (Synechococcus sp., δ13Cp = -16.2 ± 0.4‰) at μ = 0.1 d-1. δ13Cp and δ13CFA values increased by ≃ 2.5‰ for the mixed algal consortium and for P. tricornutum when growth rates were increased from 0.1 to 1.4 d-1. We compared our estimates of δ13Cp and δ13CFA values for MPB with previous measurements of δ13CTOC and δ13CFA values for other carbon sources in the Arctic, including ice-derived, terrestrial, and pelagic organic matter. We found that MPB values were significantly distinct from

  13. Regional Modelling of Air Quality in the Canadian Arctic: Impact of marine shipping and North American wild fire emissions

    Science.gov (United States)

    Gong, W.; Beagley, S. R.; Zhang, J.; Cousineau, S.; Sassi, M.; Munoz-Alpizar, R.; Racine, J.; Menard, S.; Chen, J.

    2015-12-01

    Arctic atmospheric composition is strongly influenced by long-range transport from mid-latitudes as well as processes occurring in the Arctic locally. Using an on-line air quality prediction model GEM-MACH, simulations were carried out for the 2010 northern shipping season (April - October) over a regional Arctic domain. North American wildfire emissions and Arctic shipping emissions were represented, along with other anthropogenic and biogenic emissions. Sensitivity studies were carried out to investigate the principal sources and processes affecting air quality in the Canadian Northern and Arctic regions. In this paper, we present an analysis of sources, transport, and removal processes on the ambient concentrations and atmospheric loading of various pollutants with air quality and climate implications, such as, O3, NOx, SO2, CO, and aerosols (sulfate, black carbon, and organic carbon components). Preliminary results from a model simulation of a recent summertime Arctic field campaign will also be presented.

  14. The amphipod scavenging guild in two Arctic fjords : seasonal variations, abundance and trophic interactions

    OpenAIRE

    Nygård, Henrik Andreas; Berge, Jørgen; Søreide, Janne; Vihtakari, Mikko; Falk-Petersen, Stig

    2012-01-01

    Scavenging amphipods are important for the circulation and dispersal of organic material in the marine environment. Despite their dominance in the scavenging guild and importance in the food web, little is known about Arctic amphipods and their feeding preferences. We studied the amphipod scavenging guild using baited traps for one full year to increase our understanding of its seasonal variations. Two Arctic fjords with contrasting hydrographical conditions were studied: Adventfjorden, which...

  15. Avoiding whales and wellheads: technology lightens impact of marine seismic on fragile Arctic ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Eaton, S.

    2001-09-01

    To minimize environmental impact, Anderson Exploration Ltd and WesternGeco are using new technologies that include state-of-the-art satellite systems for tracking whales, icebergs, ships and aircraft, and a pollutant-free means of keeping the streamers, or marine recording cables, from sinking. Using WesternGeco's satellite-based vehicle tracking system (VTS), ground personnel at a base camp can instantaneously determine the whereabouts of the icebreaker {sup G}eco Snapper' and the company's two vessels surveying the ocean floor. In the air, the VTS tracks the flight paths and altitudes of WesternGeco's Bell 212 helicopter and Twin Otter planes used to monitor whales and icebergs. From the bridge of the Geco Snapper, using GPS units located on the six air gun arrays and the three marine streamers which extend four kms behind the vessel, data are recorded in real time on the positions of the data acquisition equipment relative to the vessel and relative to water depth or proximity to the sea floor. The Geco Snapper has been retrofitted with the VTS equipment in preparation for its participation in a project for acquiring what may be the first-ever seismic survey in the frigid waters of the Beaufort Sea. Instead of being filled with gasoline, the streamers trailing the vessel are foam-filled, consequently, they are extremely safe and environmentally friendly.

  16. Rapid Environmental Change Drives Increased Land Use by an Arctic Marine Predator.

    Science.gov (United States)

    Atwood, Todd C; Peacock, Elizabeth; McKinney, Melissa A; Lillie, Kate; Wilson, Ryan; Douglas, David C; Miller, Susanne; Terletzky, Pat

    2016-01-01

    In the Arctic Ocean's southern Beaufort Sea (SB), the length of the sea ice melt season (i.e., period between the onset of sea ice break-up in summer and freeze-up in fall) has increased substantially since the late 1990s. Historically, polar bears (Ursus maritimus) of the SB have mostly remained on the sea ice year-round (except for those that came ashore to den), but recent changes in the extent and phenology of sea ice habitat have coincided with evidence that use of terrestrial habitat is increasing. We characterized the spatial behavior of polar bears spending summer and fall on land along Alaska's north coast to better understand the nexus between rapid environmental change and increased use of terrestrial habitat. We found that the percentage of radiocollared adult females from the SB subpopulation coming ashore has tripled over 15 years. Moreover, we detected trends of earlier arrival on shore, increased length of stay, and later departure back to sea ice, all of which were related to declines in the availability of sea ice habitat over the continental shelf and changes to sea ice phenology. Since the late 1990s, the mean duration of the open-water season in the SB increased by 36 days, and the mean length of stay on shore increased by 31 days. While on shore, the distribution of polar bears was influenced by the availability of scavenge subsidies in the form of subsistence-harvested bowhead whale (Balaena mysticetus) remains aggregated at sites along the coast. The declining spatio-temporal availability of sea ice habitat and increased availability of human-provisioned resources are likely to result in increased use of land. Increased residency on land is cause for concern given that, while there, bears may be exposed to a greater array of risk factors including those associated with increased human activities. PMID:27249673

  17. Rapid Environmental Change Drives Increased Land Use by an Arctic Marine Predator

    Science.gov (United States)

    Atwood, Todd C.; Peacock, Elizabeth; McKinney, Melissa A.; Lillie, Kate; Wilson, Ryan; Douglas, David C.; Miller, Susanne; Terletzky, Pat

    2016-01-01

    In the Arctic Ocean’s southern Beaufort Sea (SB), the length of the sea ice melt season (i.e., period between the onset of sea ice break-up in summer and freeze-up in fall) has increased substantially since the late 1990s. Historically, polar bears (Ursus maritimus) of the SB have mostly remained on the sea ice year-round (except for those that came ashore to den), but recent changes in the extent and phenology of sea ice habitat have coincided with evidence that use of terrestrial habitat is increasing. We characterized the spatial behavior of polar bears spending summer and fall on land along Alaska’s north coast to better understand the nexus between rapid environmental change and increased use of terrestrial habitat. We found that the percentage of radiocollared adult females from the SB subpopulation coming ashore has tripled over 15 years. Moreover, we detected trends of earlier arrival on shore, increased length of stay, and later departure back to sea ice, all of which were related to declines in the availability of sea ice habitat over the continental shelf and changes to sea ice phenology. Since the late 1990s, the mean duration of the open-water season in the SB increased by 36 days, and the mean length of stay on shore increased by 31 days. While on shore, the distribution of polar bears was influenced by the availability of scavenge subsidies in the form of subsistence-harvested bowhead whale (Balaena mysticetus) remains aggregated at sites along the coast. The declining spatio-temporal availability of sea ice habitat and increased availability of human-provisioned resources are likely to result in increased use of land. Increased residency on land is cause for concern given that, while there, bears may be exposed to a greater array of risk factors including those associated with increased human activities. PMID:27249673

  18. Rapid Environmental Change Drives Increased Land Use by an Arctic Marine Predator.

    Directory of Open Access Journals (Sweden)

    Todd C Atwood

    Full Text Available In the Arctic Ocean's southern Beaufort Sea (SB, the length of the sea ice melt season (i.e., period between the onset of sea ice break-up in summer and freeze-up in fall has increased substantially since the late 1990s. Historically, polar bears (Ursus maritimus of the SB have mostly remained on the sea ice year-round (except for those that came ashore to den, but recent changes in the extent and phenology of sea ice habitat have coincided with evidence that use of terrestrial habitat is increasing. We characterized the spatial behavior of polar bears spending summer and fall on land along Alaska's north coast to better understand the nexus between rapid environmental change and increased use of terrestrial habitat. We found that the percentage of radiocollared adult females from the SB subpopulation coming ashore has tripled over 15 years. Moreover, we detected trends of earlier arrival on shore, increased length of stay, and later departure back to sea ice, all of which were related to declines in the availability of sea ice habitat over the continental shelf and changes to sea ice phenology. Since the late 1990s, the mean duration of the open-water season in the SB increased by 36 days, and the mean length of stay on shore increased by 31 days. While on shore, the distribution of polar bears was influenced by the availability of scavenge subsidies in the form of subsistence-harvested bowhead whale (Balaena mysticetus remains aggregated at sites along the coast. The declining spatio-temporal availability of sea ice habitat and increased availability of human-provisioned resources are likely to result in increased use of land. Increased residency on land is cause for concern given that, while there, bears may be exposed to a greater array of risk factors including those associated with increased human activities.

  19. Proceedings of the twenty-first Arctic and marine oilspill program (AMOP) technical seminar

    International Nuclear Information System (INIS)

    A total of 62 papers were presented at this conference which examined the latest technologies applicable to marine oil spills. The conference was divided into 11 sessions, each dealing with a different aspect of oil spills. Based on session titles, the principal areas of concern were: (1) physical and chemical properties and behaviour of oils and emulsions, (2) activity updates, risk analysis and contingency planning, (3) oil spill treating agents, (4) oil spill containment and recovery, (5) spill modelling, (6) biological effects of an oil spill, (7) in situ burning at oil spill sites, (8) biodegradation, (9) detection, tracking and remote sensing, and (10) shoreline protection and cleanup. Seven papers on various aspects of oil spills were included in the poster session. refs., tabs., figs

  20. Interaction strength combinations and the overfishing of a marine food web

    OpenAIRE

    Carlos J Melián; Bascompte, Jordi; Sala, Enric

    2005-01-01

    The stability of ecological communities largely depends on the strength of interactions between predators and their prey. Here we show that these interaction strengths are structured nonran- domly in a large Caribbean marine food web. Specifically, the cooccurrence of strong interactions on two consecutive levels of food chains occurs less frequently than expected by chance. Even when they occur, these strongly interacting chains are accompa- nied by strong omnivory more often than expected ...

  1. The Influence of Processing on the DNA Integrity in Several Raw Materials of Marine Foods

    OpenAIRE

    Yuan Xiao; Zhang Xuejiao; Xu Zichu; Wu Wenhui

    2015-01-01

    With the development of molecular biotechnology, methods for identification of marine food are developed from protein to DNA. The experimental materials are striped bass, Sturgeon and mandarin fish. They were processed with boiling, salting and microwave-heating methods. DNA-based research has been conducted in almost every corner in food material identification. This study is mainly about the identification methods of distinguishing processed aquatic products and the influence of processing ...

  2. Accumulation of organochlorines and brominated flame retardants in estuarine and marine food chains: Field measurements and model calculations

    NARCIS (Netherlands)

    Veltman, K.; Hendriks, J.; Huijbregts, M.; Leonards, P.E.G.; Heuvel-Greve, van den M.J.; Vethaak, D.

    2005-01-01

    Food chain accumulation of organochlorines and brominated flame retardants in estuarine and marine environments is compared to model estimations and fresh water field data. The food chain consists of herbivores, detritivores and primary and secondary carnivores i.e. fish, fish-eating birds and marin

  3. Marine gravity field for oil and mineral exploration — Improvements in the Arctic from CryoSat-2 SAR altimetry

    DEFF Research Database (Denmark)

    Andersen, Ole Baltazar; Jain, Maulik; Knudsen, Per

    2014-01-01

    The availability of Cryosat-2 with its coverage throughout the Arctic Ocean up to 88N is a quantum leap forward for altimetric gravity field modeling and here we have tried to quantify the improvement of Cryosat-2 to global and particularly Arctic altimetric gravity field modeling through a compa...

  4. Modeling bioaccumulation and biomagnification of nonylphenol and its ethoxylates in estuarine-marine food chains

    NARCIS (Netherlands)

    Korsman, J.C.; Schipper, A.M.; Vos, de M.G.; Heuvel-Greve, van den M.J.; Vethaak, A.D.; Voogt, de Pim; Hendriks, A.J.

    2015-01-01

    There are several studies on bioaccumulation and biomagnification of nonylphenol (NP) and its ethoxylates (NPEOs), but their toxico-kinetic mechanisms remain unclear. In the present investigation, we explored the accumulation of NP and NPEOs in estuarine-marine food chains with a bioaccumulation

  5. Modeling bioaccumulation and biomagnification of nonylphenol and its ethoxylates in estuarine-marine food chains

    NARCIS (Netherlands)

    J.C. Korsman; A.M. Schipper; M.G. de Vos; M.J. van den Heuvel-Greve; A.D. Vethaak; P. de Voogt; A.J. Hendriks

    2015-01-01

    There are several studies on bioaccumulation and biomagnification of nonylphenol (NP) and its ethoxylates (NPEOs), but their toxico-kinetic mechanisms remain unclear. In the present investigation, we explored the accumulation of NP and NPEOs in estuarine-marine food chains with a bioaccumulation mod

  6. Sub regional cooperation and protection of the arctic marine environments: The Barents Sea

    Energy Technology Data Exchange (ETDEWEB)

    Stokke, Olav Schram

    1997-07-01

    The report deals with questions related to effectiveness of subregional co-operation in the Barents Sea. Efforts have differed from global processes by their clearer programmatic profile. Relatively more resources, in terms of both expertise and financial funds, have been invested in order to enhance the knowledge-base for management decisions in the region as well as the administrative and technical capacity to avoid behaviour liable to threaten the marine environment. Many of the programmatic activities encouraged at other levels have been planned, financed and organised at the subregional level. Comparatively less attention has been given to establishing new regulative norms for environmental protection from either industrial or military activity in the region. The Regional Council ensures that both county level decision makers and representatives of the indigenous population are involved. A point is the general balance between the environmental and the economic component. Moreover, the inclusiveness of the Barents Council provides linkages to potential partners in development found beyond the Barents Sea area. The subregional level has served to relate environmental protection to broader foreign policy issues and has strengthened environmental networks across the Nordic Russian divide which in turn has generated financial resources and expertise. The main reason for the higher fund raising capacity of subregional processes is that geographic proximity ensures denser networks of interdependence partly by the fact that Nordic neighbours have a clear self interest in financing environmental projects in Russia, particularly those addressing industrial pollution from the border areas and those designed to prevent dumping of radioactive waste and partly by ensuring that environmental projects may serve broader purposes associated with national security. The willingness on the part of Norway and other Nordic states to use their financial powers for problem solving

  7. Subregional cooperation and protection of the arctic marine environment: The Barents Sea

    International Nuclear Information System (INIS)

    The report deals with questions related to effectiveness of subregional co-operation in the Barents Sea. Efforts have differed from global processes by their clearer programmatic profile. Relatively more resources, in terms of both expertise and financial funds, have been invested in order to enhance the knowledge-base for management decisions in the region as well as the administrative and technical capacity to avoid behaviour liable to threaten the marine environment. Many of the programmatic activities encouraged at other levels have been planned, financed and organised at the subregional level. Comparatively less attention has been given to establishing new regulative norms for environmental protection from either industrial or military activity in the region. The Regional Council ensures that both county level decision makers and representatives of the indigenous population are involved. A point is the general balance between the environmental and the economic component. Moreover, the inclusiveness of the Barents Council provides linkages to potential partners in development found beyond the Barents Sea area. The subregional level has served to relate environmental protection to broader foreign policy issues and has strengthened environmental networks across the Nordic Russian divide which in turn has generated financial resources and expertise. The main reason for the higher fund raising capacity of subregional processes is that geographic proximity ensures denser networks of interdependence partly by the fact that Nordic neighbours have a clear self interest in financing environmental projects in Russia, particularly those addressing industrial pollution from the border areas and those designed to prevent dumping of radioactive waste and partly by ensuring that environmental projects may serve broader purposes associated with national security. The willingness on the part of Norway and other Nordic states to use their financial powers for problem solving

  8. Environmental Assessment for a Marine Geophysical Survey of Parts of the Arctic Ocean, August-September 2010

    Science.gov (United States)

    Haley, Beth; Ireland, Darren; Childs, Jonathan R.

    2010-01-01

    According to the United Nations Convention on the Law of the Sea (UNCLOS), individual nations? sovereign rights extend to 200 nautical miles (n.mi.) (370 km) offshore or to a maritime boundary in an area called the continental shelf. These rights include jurisdiction over all resources in the water column and on and beneath the seabed. Article 76 of UNCLOS also establishes the criteria to determine areas beyond the 200 n.mi. (370 km) limit that could be defined as ?extended continental shelf,? where a nation could extend its sovereign rights over the seafloor and sub-seafloor (As used in UNCLOS, ?continental shelf? refers to a legally defined region of the sea floor rather than a morphological shallow-water area adjacent to continents commonly used by geologists and hydrographers.). This jurisdiction provided in Article 76 includes resources on and below the seafloor but not in the water column. The United States has been acquiring data to determine the outer limits of its extended continental shelf in the Arctic and has a vested interest in declaring and receiving international recognition of the reach of its extended continental shelf. The U.S. collaborated with Canada in 2008 and 2009 on extended continental shelf studies in the Arctic Ocean. The U.S. Coast Guard (USCG) Cutter Healy worked with the Canadian Coast Guard ship Louis S. St. Laurent to map the continental shelf beyond 200 n.mi. (370 km) in the Arctic. Each icebreaking vessel contributed different capabilities in order to collect data needed by both nations more efficiently in order to save money, avoid redundancy, and foster cooperation. Generally, the Healy collects bathymetric (sea-floor topography) data and the Louis S. St. Laurent collects seismic reflection profile data. The vessels work in concert when ice conditions are heavy, with one vessel breaking ice for the ship collecting data. The Canadian Environmental Assessments for these projects are available on line at http://www.ceaa.gc.ca/052

  9. The role of photosynthesis and food uptake for the growth of marine mixotrophic dinoflagellates

    DEFF Research Database (Denmark)

    Hansen, Per Juel

    2011-01-01

    Mixotrophy (i.e. combined use of photosynthesis and food uptake for growth) is widespread among marine dinoflagellates. Species with permanent chloroplasts generally display a growth response towards irradiance like an ordinary autotrophic alga. However, some species cannot grow in the light...... phototrophic species, and food uptake marginally increased their growth rates at low irradiances. In the remaining species, food uptake increases to a large degree their growth rate when light is limiting and in some cases even when irradiance is not limiting growth. Some of these species grow relatively fast...... at high irradiances without food, while other species only grow slowly or cannot even maintain themselves at high irradiances without food. Dinoflagellates, which form symbioses with endo- and ectosymbionts are a very heterogeneous group, which have been studied only sporadically. Some species are clearly...

  10. Rescaling the trophic structure of marine food webs

    OpenAIRE

    Hussey, Nigel E.; MacNeil, M. Aaron; McMeans, Bailey C; Olin, Jill A; Dudley, Sheldon FJ; Cliff, Geremy; Wintner, Sabine P.; Fennessy, Sean T; Fisk, Aaron T.

    2013-01-01

    Measures of trophic position (TP) are critical for understanding food web interactions and human-mediated ecosystem disturbance. Nitrogen stable isotopes (δ15N) provide a powerful tool to estimate TP but are limited by a pragmatic assumption that isotope discrimination is constant (change in δ15N between predator and prey, Δ15N = 3.4‰), resulting in an additive framework that omits known Δ15N variation. Through meta-analysis, we determine narrowing discrimination from an empirical linear rela...

  11. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Northwest Arctic, Alaska: M_MAMMAL (Marine Mammal Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for seals, whales, walruses, polar bears, and Steller sea lions in Northwest Arctic, Alaska. Vector...

  12. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Northwest Arctic, Alaska: M_MAMPT (Marine Mammal Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for Steller sea lions and polar bears in Northwest Arctic, Alaska. Vector points in this data set...

  13. Application of nitrogen stable isotope analysis in size-based marine food web and macroecological research.

    Science.gov (United States)

    Jennings, Simon; Barnes, Carolyn; Sweeting, Christopher J; Polunin, Nicholas V C

    2008-06-01

    Interacting human and environmental pressures influence the structure and dynamics of marine food webs. To describe and predict the effects of these pressures, theoretical advances need to be supported by a capacity to validate the underlying models and assumptions. Here, we review recent applications of nitrogen stable isotope analysis in marine food web and macroecological research, with a focus on work that has paralleled a resurgence of interest in the development and application of size-based models. Nitrogen stable isotope data have been used to estimate intra- and inter-specific variation in trophic level, predator-prey size ratios, transfer efficiency, food chain length, relationships between predator and prey species diversity and the dynamics of energy use. Many of these estimates have contributed to the development, testing and parameterisation of food web and ecosystem models, some of which have been used to establish baselines for assessing the scale of human impacts. The interpretation of results depends on assumed fractionation but, when supported by sensitivity analyses and experimental validation, nitrogen stable isotope data provide valuable insights into the structuring of marine communities and ecosystems. PMID:18438766

  14. Distributions of low molecular weight dicarboxylic acids, ketoacids and α-dicarbonyls in the marine aerosols collected over the Arctic Ocean during late summer

    Directory of Open Access Journals (Sweden)

    K. Kawamura

    2012-08-01

    Full Text Available Oxalic and other small dicarboxylic acids have been reported as important water-soluble organic constituents of atmospheric aerosols from different environments. Their molecular distributions are generally characterized by the predominance of oxalic acid (C2 followed by malonic (C3 and/or succinic (C4 acids. In this study, we collected marine aerosols from the Arctic Ocean during late summer in 2009 when sea ice is retreated. The marine aerosols were analyzed for the molecular distributions of dicarboxylic acids as well as ketocarboxylic acids and α-dicarbonyls to better understand the source of water-soluble organics and their photochemical processes in the high Arctic marine atmosphere. We found that diacids are more abundant than ketoacids and α-dicarbonyls, but their concentrations are generally low (< 30 ng m−3, except for one sample (up to 70 ng m−3 that was collected near the mouth of Mackenzie River during clear sky condition. Although the molecular compositions of diacids are in general characterized by the predominance of oxalic acid, a depletion of C2 was found in two samples in which C4 became the most abundant. Similar depletion of oxalic acid has previously been reported in the Arctic aerosols collected at Alert after polar sunrise and in the summer aerosols from the coastal Antarctica. Because the marine aerosols that showed a depletion of C2 were observed under the overcast and/or foggy conditions, we suggest that a photochemical decomposition of oxalic acid may have occurred in aqueous phase of aerosols over the Arctic Ocean via the photo dissociation of oxalate-Fe (III complex. We also determined stable carbon isotopic compositions (δ13C of bulk aerosol carbon and individual diacids. The δ13C of bulk aerosols showed −26.5‰ (range: −29.7‰ to −24.7‰, suggesting that marine aerosol carbon is derived

  15. Distributions of low molecular weight dicarboxylic acids, ketoacids and α-dicarbonyls in the marine aerosols collected over the Arctic Ocean during late summer

    Directory of Open Access Journals (Sweden)

    K. Kawamura

    2012-11-01

    Full Text Available Oxalic and other small dicarboxylic acids have been reported as important water-soluble organic constituents of atmospheric aerosols from different environments. Their molecular distributions are generally characterized by the predominance of oxalic acid (C2 followed by malonic (C3 and/or succinic (C4 acids. In this study, we collected marine aerosols from the Arctic Ocean during late summer in 2009 when sea ice was retreating. The marine aerosols were analyzed for the molecular distributions of dicarboxylic acids as well as ketocarboxylic acids and α-dicarbonyls to better understand the source of water-soluble organics and their photochemical processes in the high Arctic marine atmosphere. We found that diacids are more abundant than ketoacids and α-dicarbonyls, but their concentrations are generally low (< 30 ng m−3, except for one sample (up to 70 ng m−3 that was collected near the mouth of Mackenzie River during clear sky condition. Although the molecular compositions of diacids are in general characterized by the predominance of oxalic acid, a depletion of C2 was found in two samples in which C4 became the most abundant. Similar depletion of oxalic acid has previously been reported in the Arctic aerosols collected at Alert after polar sunrise and in the summer aerosols from the coast of Antarctica. Because the marine aerosols that showed a depletion of C2 were collected under the overcast and/or foggy conditions, we suggest that a photochemical decomposition of oxalic acid may have occurred in aqueous phase of aerosols over the Arctic Ocean via the photo dissociation of oxalate-Fe (III complex. We also determined stable carbon isotopic compositions (δ13C of bulk aerosol carbon and individual diacids. The δ13C of bulk aerosols showed −26.5‰ (range: −29.7 to −24.7‰, suggesting that marine aerosol carbon is derived

  16. Copper transfer and influence on a marine food chain

    Energy Technology Data Exchange (ETDEWEB)

    Edding, M.; Tala, F. [Universidad Catolica del Norte, Coquimbo (Chile)

    1996-12-31

    Copper is an essential element, required for normal growth by all plants and animals; and a regular constituent in the environment (Lewis and Cave 1982; Lewis 1994). This heavy metal is an essential micronutrient that at higher concentrations can be deleterious to algae and other aquatic biota (Chang and Sibley 1993). Copper toxicity to algae depends upon the individual species, their physiological and environmental conditions, and the chemical forms of metal in the medium (Sunda and Gullard 1976). When copper is accumulated by phytoplankton it can be transferred and may produce toxic effects on zooplankton (Wikfors and Ukeles 1982). Different species of microalgae present different capacities of resistance to copper. Cyanophyceae pre-cultured in a Cu-enriched medium (635 {mu}gCu{center_dot}L{sup {minus}1}) showed an EC{sub 50} that could reach 318 {mu}gCu{center_dot}L{sup {minus}1} for Plectonema radiosum and 339 {mu}gCu{center_dot}L{sup {minus}1} in Phormidium sp. (Takamura et al. 1990). Scenedesmus, Selenastrum and Chlorella were reported able to accumulate copper and other metal ions with an efficiency of 67-98% (Brady et al. 1994). Also, Dunaliella resisted concentrations form 0.38 mgCu{center_dot}L{sup {minus}1} (D. minuta) up to 50.8 mgCu{center_dot}L{sup {minus}1} (D. acidophila), depending on the pH of the medium (Grimmler et al. 1991). One the microalgae are copper-enriched, the copper that is part of the cell can be transferred to the surrounding water and to its predator producing uncertain effects. This study observed the effect of copper on the growth of Dunaliella tertiolecta and Isochrysis galbana that are currently used as food for hatchery-grown scallop larvae (Argopecten purpuratus). We observed the path of copper form the water column into the microalgal cell and the effect of copper-enriched food on the scallop larvae. 16 refs., 3 figs., 2 tabs.

  17. Origin of marine debris is related to disposable packs of ultra-processed food.

    Science.gov (United States)

    Andrades, Ryan; Martins, Agnaldo S; Fardim, Lorena M; Ferreira, Juliana S; Santos, Robson G

    2016-08-15

    Marine debris is currently distributed worldwide, and the discard and contamination pose hazards to human and wildlife health. One of the gaps in debris science is tracking the source of debris to better evaluate and avoid the pathway of debris from the source to marine environment. For this, we evaluated three beaches of different urbanization levels and environmental influences; a low urbanized beach, a highly urbanized beach and a non-urbanized estuary-associated beach, in order to determine the sources and original use of debris. Plastic was the major material found on beaches, and the urbanized beach recorded the highest debris densities. Marine debris was primarily from land-based sources, and the debris recorded in all beaches was mainly assigned as food-related items. Our results highlight the major presence of disposable and short-lived products comprising the majority of debris that enters the ocean and draw attention to the unsustainable lifestyle of current society. PMID:27315750

  18. Impact of biodiversity loss on production in complex marine food webs mitigated by prey-release.

    Science.gov (United States)

    Fung, Tak; Farnsworth, Keith D; Reid, David G; Rossberg, Axel G

    2015-01-01

    Public concern over biodiversity loss is often rationalized as a threat to ecosystem functioning, but biodiversity-ecosystem functioning (BEF) relations are hard to empirically quantify at large scales. We use a realistic marine food-web model, resolving species over five trophic levels, to study how total fish production changes with species richness. This complex model predicts that BEF relations, on average, follow simple Michaelis-Menten curves when species are randomly deleted. These are shaped mainly by release of fish from predation, rather than the release from competition expected from simpler communities. Ordering species deletions by decreasing body mass or trophic level, representing 'fishing down the food web', accentuates prey-release effects and results in unimodal relationships. In contrast, simultaneous unselective harvesting diminishes these effects and produces an almost linear BEF relation, with maximum multispecies fisheries yield at ≈40% of initial species richness. These findings have important implications for the valuation of marine biodiversity. PMID:25799523

  19. Combined effects of global climate change and regional ecosystem drivers on an exploited marine food web

    DEFF Research Database (Denmark)

    Niiranen, S.; Yletyinen, J.; Tomczak, M.T.;

    2013-01-01

    Changes in climate, in combination with intensive exploitation of marine resources, have caused large-scale reorganizations in many of the world's marine ecosystems during the past decades. The Baltic Sea in Northern Europe is one of the systems most affected. In addition to being exposed...... approach to project how the interaction of climate, nutrient loads, and cod fishing may affect the future of the open Central Baltic Sea food web. Regionally downscaled global climate scenarios were, in combination with three nutrient load scenarios, used to drive an ensemble of three regional...... biogeochemical models (BGMs). An Ecopath with Ecosim food web model was then forced with the BGM results from different nutrient-climate scenarios in combination with two different cod fishing scenarios. The results showed that regional management is likely to play a major role in determining the future...

  20. Marine microalgae used as food supplements and their implication in preventing cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    Mimouni Virginie

    2015-07-01

    Full Text Available Marine microalgae are photosynthetic microorganisms producing numerous bioactive molecules of interest for health and disease care such as lipids rich in omega-3 fatty acids -as eicosapentaenoic acid (EPA, 20:5 n-3 and docosahexaenoic acid (DHA, 22:6 n-3- and carotenoids (e.g., β-carotene, fucoxanthin, astaxanthin. It has already been shown that these molecules, individually used, are benefic in the prevention of diseases such as those associated with the cardiovascular risks, but also in some carcinomas. When these molecules are combined, synergistic effects may be observed. Microalgae, as a dietary supplement, can be used to study these synergistic effects in animal models in which dyslipidemia can be induced by a nutrition treatment. Different marine microalgae of interest are studied in this context to determine their potential effect as an alternative source to marine omega-3 rich fish oils, actually widely used for human health. Actually, the pharmaceutical and nutrition industries are developing health research programs involving microalgae, trying to limit the dramatic reduction of fish stocks and the associated pollution in the marine environment. The aim of this review is threefold: (1 to present research on lipids, particularly long chain polyunsaturated fatty acids, as components of marine microalgae used as food supplements; (2 to present the health benefits of some microalgae or their extracts, in particular in the prevention of cardiovascular diseases and (3 to highlight the role of Odontella aurita, a marine microalga rich in EPA used as food supplement with the aim of preventing cardiovascular diseases.

  1. Contrasting food web factor and body size relationships with Hg and Se concentrations in marine biota.

    Directory of Open Access Journals (Sweden)

    Roxanne Karimi

    Full Text Available Marine fish and shellfish are primary sources of human exposure to mercury, a potentially toxic metal, and selenium, an essential element that may protect against mercury bioaccumulation and toxicity. Yet we lack a thorough understanding of Hg and Se patterns in common marine taxa, particularly those that are commercially important, and how food web and body size factors differ in their influence on Hg and Se patterns. We compared Hg and Se content among marine fish and invertebrate taxa collected from Long Island, NY, and examined associations between Hg, Se, body length, trophic level (measured by δ(15N and degree of pelagic feeding (measured by δ(13C. Finfish, particularly shark, had high Hg content whereas bivalves generally had high Se content. Both taxonomic differences and variability were larger for Hg than Se, and Hg content explained most of the variation in Hg:Se molar ratios among taxa. Finally, Hg was more strongly associated with length and trophic level across taxa than Se, consistent with a greater degree of Hg bioaccumulation in the body over time, and biomagnification through the food web, respectively. Overall, our findings indicate distinct taxonomic and ecological Hg and Se patterns in commercially important marine biota, and these patterns have nutritional and toxicological implications for seafood-consuming wildlife and humans.

  2. Contrasting food web factor and body size relationships with Hg and Se concentrations in marine biota.

    Science.gov (United States)

    Karimi, Roxanne; Frisk, Michael; Fisher, Nicholas S

    2013-01-01

    Marine fish and shellfish are primary sources of human exposure to mercury, a potentially toxic metal, and selenium, an essential element that may protect against mercury bioaccumulation and toxicity. Yet we lack a thorough understanding of Hg and Se patterns in common marine taxa, particularly those that are commercially important, and how food web and body size factors differ in their influence on Hg and Se patterns. We compared Hg and Se content among marine fish and invertebrate taxa collected from Long Island, NY, and examined associations between Hg, Se, body length, trophic level (measured by δ(15)N) and degree of pelagic feeding (measured by δ(13)C). Finfish, particularly shark, had high Hg content whereas bivalves generally had high Se content. Both taxonomic differences and variability were larger for Hg than Se, and Hg content explained most of the variation in Hg:Se molar ratios among taxa. Finally, Hg was more strongly associated with length and trophic level across taxa than Se, consistent with a greater degree of Hg bioaccumulation in the body over time, and biomagnification through the food web, respectively. Overall, our findings indicate distinct taxonomic and ecological Hg and Se patterns in commercially important marine biota, and these patterns have nutritional and toxicological implications for seafood-consuming wildlife and humans. PMID:24019976

  3. Joint Effects of Nutrients and Contaminants on the Dynamics of a Food Chain in Marine Ecosystems

    OpenAIRE

    Bacelar, Flora S.; DUERI Sibylle; Hernández-García, Emilio; Zaldívar, José Manuel

    2008-01-01

    We analyze the joint effect of contaminants and nutrient loading on population dynamics of marine food chains by means of bifurcation analysis. Contaminant toxicity is assumed to alter mortality of some species with a sigmoidal dose–response relationship. A generic effect of pollutants is to delay transitions to complex dynamical states towards higher nutrient load values, but more counterintuitive consequences arising from indirect effects are described. In particular, the top predator seems...

  4. Cephalopods as Vectors of Harmful Algal Bloom Toxins in Marine Food Webs

    OpenAIRE

    Rui Rosa; Pedro Costa; Lopes, Vanessa M.; Ana Rita Lopes

    2013-01-01

    Here we summarize the current knowledge on the transfer and accumulation of harmful algal bloom (HAB)-related toxins in cephalopods (octopods, cuttlefishes and squids). These mollusks have been reported to accumulate several HAB-toxins, namely domoic acid (DA, and its isomers), saxitoxin (and its derivatives) and palytoxin (and palytoxin-like compounds) and, therefore, act as HAB-toxin vectors in marine food webs. Coastal octopods and cuttlefishes store considerably high levels of DA (amnesic...

  5. Impact of biodiversity loss on production in complex marine food webs mitigated by prey-release

    OpenAIRE

    Fung, Tak; Farnsworth, Keith D.; Reid, David G.; Rossberg, Axel G.

    2015-01-01

    Abstract Public concern over biodiversity loss is often rationalized as a threat to ecosystem functioning, but biodiversity-ecosystem functioning (BEF) relations are hard to empirically quantify at large scales. We use a realistic marine food-web model, resolving species over five trophic levels, to study how total fish production changes with species richness. This complex model predicts that BEF relations, on average, follow simple Michaelis–Menten curves when species are randomly...

  6. Food web flows through a sub-arctic deep-sea benthic community

    NARCIS (Netherlands)

    Gontikaki, E.; Van Oevelen, D.; Soetaert, K.E.R.; Prof. Witte, U.

    2011-01-01

    The benthic food web of the deep Faroe–Shetland Channel (FSC) was modelled by using the linear inverse modelling methodology. The reconstruction of carbon pathways by inverse analysis was based on benthic oxygen uptake rates, biomass data and transfer of labile carbon through the food web as reveale

  7. Greater shrub dominance alters breeding habitat and food resources for migratory songbirds in Alaskan arctic tundra.

    Science.gov (United States)

    Boelman, Natalie T; Gough, Laura; Wingfield, John; Goetz, Scott; Asmus, Ashley; Chmura, Helen E; Krause, Jesse S; Perez, Jonathan H; Sweet, Shannan K; Guay, Kevin C

    2015-04-01

    Climate warming is affecting the Arctic in multiple ways, including via increased dominance of deciduous shrubs. Although many studies have focused on how this vegetation shift is altering nutrient cycling and energy balance, few have explicitly considered effects on tundra fauna, such as the millions of migratory songbirds that breed in northern regions every year. To understand how increasing deciduous shrub dominance may alter breeding songbird habitat, we quantified vegetation and arthropod community characteristics in both graminoid and shrub dominated tundra. We combined measurements of preferred nest site characteristics for Lapland longspurs (Calcarius lapponicus) and Gambel's White-crowned sparrows (Zonotrichia leucophrys gambelii) with modeled predictions for the distribution of plant community types in the Alaskan arctic foothills region for the year 2050. Lapland longspur nests were found in sedge-dominated tussock tundra where shrub height does not exceed 20 cm, whereas White-crowned sparrows nested only under shrubs between 20 cm and 1 m in height, with no preference for shrub species. Shrub canopies had higher canopy-dwelling arthropod availability (i.e. small flies and spiders) but lower ground-dwelling arthropod availability (i.e. large spiders and beetles). Since flies are the birds' preferred prey, increasing shrubs may result in a net enhancement in preferred prey availability. Acknowledging the coarse resolution of existing tundra vegetation models, we predict that by 2050 there will be a northward shift in current White-crowned sparrow habitat range and a 20-60% increase in their preferred habitat extent, while Lapland longspur habitat extent will be equivalently reduced. Our findings can be used to make first approximations of future habitat change for species with similar nesting requirements. However, we contend that as exemplified by this study's findings, existing tundra modeling tools cannot yet simulate the fine-scale habitat

  8. Lipids of Prokaryotic Origin at the Base of Marine Food Webs

    Directory of Open Access Journals (Sweden)

    Maria José Caramujo

    2012-11-01

    Full Text Available In particular niches of the marine environment, such as abyssal trenches, icy waters and hot vents, the base of the food web is composed of bacteria and archaea that have developed strategies to survive and thrive under the most extreme conditions. Some of these organisms are considered “extremophiles” and modulate the fatty acid composition of their phospholipids to maintain the adequate fluidity of the cellular membrane under cold/hot temperatures, elevated pressure, high/low salinity and pH. Bacterial cells are even able to produce polyunsaturated fatty acids, contrarily to what was considered until the 1990s, helping the regulation of the membrane fluidity triggered by temperature and pressure and providing protection from oxidative stress. In marine ecosystems, bacteria may either act as a sink of carbon, contribute to nutrient recycling to photo-autotrophs or bacterial organic matter may be transferred to other trophic links in aquatic food webs. The present work aims to provide a comprehensive review on lipid production in bacteria and archaea and to discuss how their lipids, of both heterotrophic and chemoautotrophic origin, contribute to marine food webs.

  9. Gaia Paradigm: A Biotic Origin Of The Polar Sunrise Arctic Bromine Explosion

    OpenAIRE

    Iudin, M.

    2008-01-01

    The main attention is given to discussion of the natural causes and regularities of the Arctic bromine pollution. We make notice of marine microbial organisms and their metabolism as a prime driving force for the elemental biogeochemical cycles. One of the important conclusions of this study is on similarity between ocean bromine concentrating as by-product of the marine microbial activities and nitrogen fixation by soil bacteria. In both cases, microbial organisms and their food webs maintai...

  10. Impacts of decline harvest of country food on nutrient intake among Inuit in Arctic Canada: impact of climate change and possible adaptation plan

    Directory of Open Access Journals (Sweden)

    Renata Rosol

    2016-07-01

    Full Text Available Background: The pervasive food insecurity and the diet transition away from local, nutrient-rich country foods present a public health challenge among Inuit living in the Canadian Arctic. While environmental factors such as climate change decreased the accessibility and availability of many country food species, new species were introduced into regions where they were previously unavailable. An adaptation such as turning to alternate country food species can be a viable solution to substitute for the nutrients provided by the declined food species. The objective of this study was to estimate the impact on nutrient intake using hypothetical scenarios that current commonly harvested country foods were reduced by 50%, and were replaced with alternate or new species. Methods: Data collected during the 2007–2008 Inuit Health Survey from 36 Canadian Arctic communities spanning Nunavut, the Inuvialuit Settlement Region and Nunatsiavut were used. Results: A 50% decline in consumption of fish, whale, ringed seals and birds (the food that was reported to be in decline resulted in a significant decrease in essential nutrient intake. Possible substitute foods were identified but some nutrients such as zinc and especially vitamin D were most often found lacking in the alternative diet. Conclusions: If the alternative species are not available or feasible, more expensive and less nutritionally dense store-bought foods may be sought. Given the superior quality of country foods and their association with food security, and Inuit cultural health and personal identity, developing skills and awareness for adaptation, promoting regional sharing networks, forming a co-management agency and continuing nutritional monitoring may potentially preserve the nutritional integrity of Inuit diet, and in turn their health and cultural survival.

  11. Impacts of decline harvest of country food on nutrient intake among Inuit in Arctic Canada: impact of climate change and possible adaptation plan

    Science.gov (United States)

    Rosol, Renata; Powell-Hellyer, Stephanie; Chan, Hing Man

    2016-01-01

    Background The pervasive food insecurity and the diet transition away from local, nutrient-rich country foods present a public health challenge among Inuit living in the Canadian Arctic. While environmental factors such as climate change decreased the accessibility and availability of many country food species, new species were introduced into regions where they were previously unavailable. An adaptation such as turning to alternate country food species can be a viable solution to substitute for the nutrients provided by the declined food species. The objective of this study was to estimate the impact on nutrient intake using hypothetical scenarios that current commonly harvested country foods were reduced by 50%, and were replaced with alternate or new species. Methods Data collected during the 2007–2008 Inuit Health Survey from 36 Canadian Arctic communities spanning Nunavut, the Inuvialuit Settlement Region and Nunatsiavut were used. Results A 50% decline in consumption of fish, whale, ringed seals and birds (the food that was reported to be in decline) resulted in a significant decrease in essential nutrient intake. Possible substitute foods were identified but some nutrients such as zinc and especially vitamin D were most often found lacking in the alternative diet. Conclusions If the alternative species are not available or feasible, more expensive and less nutritionally dense store-bought foods may be sought. Given the superior quality of country foods and their association with food security, and Inuit cultural health and personal identity, developing skills and awareness for adaptation, promoting regional sharing networks, forming a co-management agency and continuing nutritional monitoring may potentially preserve the nutritional integrity of Inuit diet, and in turn their health and cultural survival. PMID:27388896

  12. Acetate, lactate, propionate, and isobutyrate as electron donors for iron and sulfate reduction in Arctic marine sediments, Svalbard

    DEFF Research Database (Denmark)

    Finke, Niko; Vandieken, Verona; Jørgensen, Bo Barker

    2007-01-01

    The contribution of volatile fatty acids (VFA) as e--donors for anaerobic terminal oxidation of organic carbon through iron and sulfate reduction was studied in Arctic fjord sediment. Dissolved inorganic carbon, Fe2+, VFA concentrations, and sulfate reduction were monitored in slurries from...

  13. Arctic soil development on a series of marine terraces on central Spitsbergen, Svalbard: a combined geochronology, fieldwork and modelling approach

    NARCIS (Netherlands)

    Meij, van der W.M.; Temme, A.J.A.M.; Kleijn, de Christian; Reimann, T.; Heuvelink, G.B.M.; Zwoliński, Zbigniew; Rachlewicz, Grzegorz; Rymer, Krzysztof; Sommer, Michael

    2016-01-01

    Soils in Arctic regions currently enjoy attention because of their sensitivity to climate change. It is therefore important to understand the natural processes and rates of development of these soils. Specifically, there is a need to quantify the rates and interactions between various landscape- and

  14. FRAM (FRontiers in Arctic marine Monitoring: The FRAM Ocean Observing System) planned efforts for integrated water column biogeochemistry

    Science.gov (United States)

    Nielsdóttir, Maria; Salter, Ian; Kanzow, Torsten; Boetius, Antje

    2015-04-01

    The Arctic is a region undergoing rapid environmental change and will be subject to multiple stressors in the coming decades. Reductions in sea ice concentration; warming, increased terrigenous inputs and Atlantification are all expected to exert a significant impact on the structure and function of Arctic ecosystems. The Fram Strait is a particularly important region because it acts as a gateway in the exchange of Atlantic and Arctic water masses. The logistical constraints in conducting year round biogeochemical measurements in such areas impose a significant limitation to our understanding of these complicated ecosystems. To address these important challenges the German ministry of research has funded a multi-million Euro infrastructure project (FRAM). Over the next five years FRAM will develop a remote access and autonomous sampling infrastructure to improve the temporal and spatial resolution of biogeochemical measurements in the Fram Strait and central Arctic. Here we present a summary of sampling strategies, technological innovations and biogeochemical parameters that will be addressed over the duration of the project. Specific emphasis will be placed on platforms for monitoring nutrient dynamics, carbonate chemistry, organic carbon flux and the development of a sustained microbial observatory.

  15. Ice rafting history and paleoceanographic reconstructions of Core 08P23 from southern Chukchi Plateau, western Arctic Ocean since Marine Isotope Stage 3

    Institute of Scientific and Technical Information of China (English)

    ZHANG Taoliang; WANG Rujian; XIAO Wenshen; CHEN Zhihua; CHEN Jianfang; CHENG Zhenbo; SUN Yechen

    2015-01-01

    Multiproxy investigations have been performed on Core 08P23 collected from the Chukchi Plateau, the western Arctic Ocean, during the Third Chinese National Arctic Expedition. The core was dated back to Ma-rine Isotope Stage (MIS) 3 by a combination of Accelerator Mass Spectrometric (AMS) carbon-14 dating and regional core correlation. A total of five prominent ice-rafted detritus (IRD) events were recognized in MIS 2 and MIS 3. The IRD sources in MIS 3 are originated from vast carbonate rock outcrops of the Canadian Arctic Archipelago and clastic quartz in MIS 2 may have a Eurasian origin. Mostδ18O andδ13C values of Neogloboquadrina pachyderma (sinistral) (Nps) in Core 08P23 are lighter than the average values of surface sediments. The lighterδ18O andδ13C values of Nps in the two brown layers in MIS 1 and MIS 3 were resulted from meltwater events; and those in the gray layers in MIS 3 were caused by the enhanced sea ice formation. Theδ18O values varied inversely withδ13C in MIS 2 indicate that the study area was covered by thick sea ice or ice sheet with low temperature and little meltwater, which prevented the biological productivity and sea-atmosphere exchange, as well as water mass ventilation. The covaried light values ofδ18O andδ13C in MIS 1 and MIS 3 were resulted from meltwater and/or brine injection.

  16. Physico-chemical properties, oxidative stability and non-enzymatic browning reactions in marine phospholipids emulsions and their applications for food enrichment

    DEFF Research Database (Denmark)

    Lu, Henna Fung Sieng; Nielsen, Nina Skall; Baron, Caroline P.;

    for food enrichment. The secondary objective was to investigate the different aspects of marine PL emulsions including: physico-chemical properties, oxidative stability and non-enzymatic browning reactions while identifying the important factors affecting their stability. The physical and oxidative...... degradation and pyrrolization) seemed to influence the oxidative stability of marine PL emulsions. Similar to marine PL emulsions, the oxidative stability and sensory acceptability of marine PL enriched products varied depending on the quality and chemical composition of marine PL used. Overall, this study...... provided new insights into the oxidative stability of marine PL and preliminary knowledge on the quality of marine PL fortified foods....

  17. Longer and less overlapping food webs in anthropogenically disturbed marine ecosystems: confirmations from the past.

    Directory of Open Access Journals (Sweden)

    Fabiana Saporiti

    Full Text Available The human exploitation of marine resources is characterised by the preferential removal of the largest species. Although this is expected to modify the structure of food webs, we have a relatively poor understanding of the potential consequences of such alteration. Here, we take advantage of a collection of ancient consumer tissues, using stable isotope analysis and SIBER to assess changes in the structure of coastal marine food webs in the South-western Atlantic through the second half of the Holocene as a result of the sequential exploitation of marine resources by hunter-gatherers, western sealers and modern fishermen. Samples were collected from shell middens and museums. Shells of both modern and archaeological intertidal herbivorous molluscs were used to reconstruct changes in the stable isotopic baseline, while modern and archaeological bones of the South American sea lion Otaria flavescens, South American fur seal Arctocephalus australis and Magellanic penguin Spheniscus magellanicus were used to analyse changes in the structure of the community of top predators. We found that ancient food webs were shorter, more redundant and more overlapping than current ones, both in northern-central Patagonia and southern Patagonia. These surprising results may be best explained by the huge impact of western sealing on pinnipeds during the fur trade period, rather than the impact of fishing on fish populations. As a consequence, the populations of pinnipeds at the end of the sealing period were likely well below the ecosystem's carrying capacity, which resulted in a release of intraspecific competition and a shift towards larger and higher trophic level prey. This in turn led to longer and less overlapping food webs.

  18. Longer and Less Overlapping Food Webs in Anthropogenically Disturbed Marine Ecosystems: Confirmations from the Past

    Science.gov (United States)

    Saporiti, Fabiana; Bearhop, Stuart; Silva, Laura; Vales, Damián G.; Zenteno, Lisette; Crespo, Enrique A.; Aguilar, Alex; Cardona, Luis

    2014-01-01

    The human exploitation of marine resources is characterised by the preferential removal of the largest species. Although this is expected to modify the structure of food webs, we have a relatively poor understanding of the potential consequences of such alteration. Here, we take advantage of a collection of ancient consumer tissues, using stable isotope analysis and SIBER to assess changes in the structure of coastal marine food webs in the South-western Atlantic through the second half of the Holocene as a result of the sequential exploitation of marine resources by hunter-gatherers, western sealers and modern fishermen. Samples were collected from shell middens and museums. Shells of both modern and archaeological intertidal herbivorous molluscs were used to reconstruct changes in the stable isotopic baseline, while modern and archaeological bones of the South American sea lion Otaria flavescens, South American fur seal Arctocephalus australis and Magellanic penguin Spheniscus magellanicus were used to analyse changes in the structure of the community of top predators. We found that ancient food webs were shorter, more redundant and more overlapping than current ones, both in northern-central Patagonia and southern Patagonia. These surprising results may be best explained by the huge impact of western sealing on pinnipeds during the fur trade period, rather than the impact of fishing on fish populations. As a consequence, the populations of pinnipeds at the end of the sealing period were likely well below the ecosystem's carrying capacity, which resulted in a release of intraspecific competition and a shift towards larger and higher trophic level prey. This in turn led to longer and less overlapping food webs. PMID:25076042

  19. The distribution of atmospheric black carbon in the marine boundary layer over the North Atlantic and the Russian Arctic Seas in July - October 2015

    Science.gov (United States)

    Shevchenko, Vladimir P.; Kopeikin, Vladimir M.; Evangeliou, Nikolaos; Novigatsky, Alexander N.; Pankratova, Natalia V.; Starodymova, Dina P.; Stohl, Andreas; Thompson, Rona

    2016-04-01

    Black carbon (BC) particles are highly efficient at absorbing visible light, which has a large potential impact on Arctic climate. However, measurement data on the distribution of BC in the atmosphere over the North Atlantic and the Russian Arctic Seas are scarce. We present measurement data on the distribution of atmospheric BC in the marine boundary layer of the North Atlantic and Baltic, North, Norwegian, Barents, White, Kara and Laptev Seas from research cruises during July 23 to October 6, 2015. During the 62nd and 63rd cruises of the RV "Akademik Mstislav Keldysh" air was filtered through Hahnemuhle fineart quarz-microfibre filters. The mass of BC on the filter was determined by measurement of the attenuation of a beam of light transmitted through the filter. Source areas were estimated by backwards trajectories of air masses calculated using NOAA's HYSPLIT model (http://www.arl.noaa.gov/ready.html) and FLEXPART model (http://www.flexpart.eu). During some parts of the cruises, air masses arrived from background areas of high latitudes, and the measured BC concentrations were low. During other parts of the cruise, air masses arrived from industrially developed areas with strong BC sources, and this led to substantially enhanced measured BC concentrations. Model-supported analyses are currently performed to use the measurement data for constraining the emission strength in these areas.

  20. Is benthic food web structure related to diversity of marine macrobenthic communities?

    Science.gov (United States)

    Sokołowski, A.; Wołowicz, M.; Asmus, H.; Asmus, R.; Carlier, A.; Gasiunaité, Z.; Grémare, A.; Hummel, H.; Lesutiené, J.; Razinkovas, A.; Renaud, P. E.; Richard, P.; Kędra, M.

    2012-08-01

    Numerical structure and the organisation of food webs within macrozoobenthic communities has been assessed in the European waters (Svalbard, Barents Sea, Baltic Sea, North Sea, Atlantic Ocean and the Mediterranean Sea) to address the interactions between biodiversity and ecosystem functioning. Abundance and classical species diversity indices (S, H', J) of macrofaunal communities were related to principal attributes of food webs (relative trophic level and food chain length, FCL) that were determined from carbon and nitrogen stable isotope values. Structure of marine macrobenthos varies substantially at a geographical scale; total abundance ranges from 63 ind. m-2 to 34,517 ind. m-2, species richness varies from 3 to 166 and the Shannon-Weaver diversity index from 0.26 to 3.26 while Pielou's evenness index is below 0.73. The major source of energy for macrobenthic communities is suspended particulate organic matter, consisting of phytoplankton and detrital particles, sediment particulate organic matter, and microphytobenthos in varying proportions. These food sources support the presence of suspension- and deposit-feeding communities, which dominate numerically on the sea floor. Benthic food webs include usually four to five trophic levels (FCL varies from 3.08 to 4.86). Most species are assigned to the second trophic level (primary consumers), fewer species are grouped in the third trophic level (secondary consumers), and benthic top predators are the least numerous. Most species cluster primarily at the lowest trophic level that is consistent with the typical organization of pyramidal food webs. Food chain length increases with biodiversity, highlighting a positive effect of more complex community structure on food web organisation. In more diverse benthic communities, energy is transferred through more trophic levels while species-poor communities sustain a shorter food chain.

  1. Effects of growth and change of food on the δ15N in marine fishes

    International Nuclear Information System (INIS)

    Information is limited concerning variation of the δ15N with growth in marine organisms and consequently the effect of growth of marine biota on the δ15N is not yet well understood. The δ15N in 26 species of marine fishes taken from Japanese coastal waters together with 4664 stomach contents of these fishes were examined to investigate the effects of food habits and growth on the δ15N. The mean δ15N for two species that fed mainly on large-size fishes and six species that fed mainly on small-size fishes were 14.5±1.0per mille and 12.8±0.7per mille, respectively. For five species that fed mainly on decapod crustaceans, two species that fed mainly on zooplankton, and three species that fed mainly on benthos (mainly Polychaeta), the δ15N were 13.0±0.7, 9.7±0.9, and 12.2±1.2per mille, respectively. The mean δ15N in the species whose prey were mainly fish or decapod crustaceans was about 3-5per mille higher than the species whose prey was mainly zooplankton. Within the four species that shift their food habits with growth to higher trophic level, the δ15N significantly increased with growth in one species (Pacific cod), while not significant increase in the δ15N with growth in the remaining species. (author)

  2. A review of the battle for food in the Barents Sea: Cod vs. marine mammals

    Directory of Open Access Journals (Sweden)

    Bjarte eBogstad

    2015-03-01

    Full Text Available Cod, harp seal and minke whale are the main top predators in the Barents Sea ecosystem. In the last decade, the abundance of cod has increased considerably, and is at a record high level. In spite of this, the growth and condition of cod has remained rather stable, although some decrease is seen in size at age of large, mature cod. During the same period, the abundance of harp seals has declined whereas the minke whale stock has been at a stable level. The body condition (blubber thickness of these two mammal stocks has, however, decreased, with the strongest decrease observed for harp seals. A possible hypothesis for explaining this is that cod outperform the marine mammal stocks in the competition for food. The main advantages for cod are most likely larger availability of food (mainly capelin during winter-spring than for marine mammals, as well as a wider range of prey species being available to cod than to marine mammals. Harp seals are more dependent on prey items found close to the ice edge than the other two predator stocks are, which could partly explain why the performance of harp seals is worse than that of the two other main top predators in the area.

  3. Food web flows through a sub-arctic deep-sea benthic community

    Science.gov (United States)

    Gontikaki, E.; van Oevelen, D.; Soetaert, K.; Witte, U.

    2011-11-01

    The benthic food web of the deep Faroe-Shetland Channel (FSC) was modelled by using the linear inverse modelling methodology. The reconstruction of carbon pathways by inverse analysis was based on benthic oxygen uptake rates, biomass data and transfer of labile carbon through the food web as revealed by a pulse-chase experiment. Carbon deposition was estimated at 2.2 mmol C m -2 d -1. Approximately 69% of the deposited carbon was respired by the benthic community with bacteria being responsible for 70% of the total respiration. The major fraction of the labile detritus flux was recycled within the microbial loop leaving merely 2% of the deposited labile phytodetritus available for metazoan consumption. Bacteria assimilated carbon at high efficiency (0.55) but only 24% of bacterial production was grazed by metazoans; the remaining returned to the dissolved organic matter pool due to viral lysis. Refractory detritus was the basal food resource for nematodes covering ∼99% of their carbon requirements. On the contrary, macrofauna seemed to obtain the major part of their metabolic needs from bacteria (49% of macrofaunal consumption). Labile detritus transfer was well-constrained, based on the data from the pulse-chase experiment, but appeared to be of limited importance to the diet of the examined benthic organisms (food web. Overall, this study provided a unique insight into the functioning of a deep-sea benthic community and demonstrated how conventional data can be exploited further when combined with state-of-the-art modelling approaches.

  4. a New Japanese Project for Arctic Climate Change Research - Grene Arctic - (Invited)

    Science.gov (United States)

    Enomoto, H.

    2013-12-01

    A new Arctic Climate Change Research Project 'Rapid Change of the Arctic Climate System and its Global Influences' has started in 2011 for a five years project. GRENE-Arctic project is an initiative of Arctic study by more than 30 Japanese universities and institutes as the flame work of GRENE (Green Network of Excellence) of MEXT (Ministry of Education, Culture, Sports, Science and Technology, Japan). The GRENE-Arctic project set four strategic research targets: 1. Understanding the mechanism of warming amplification in the Arctic 2. Understanding the Arctic system for global climate and future change 3. Evaluation of the effects of Arctic change on weather in Japan, marine ecosystems and fisheries 4. Prediction of sea Ice distribution and Arctic sea routes This project aims to realize the strategic research targets by executing following studies: -Improvement of coupled general circulation models based on validations of the Arctic climate reproducibility and on mechanism analyses of the Arctic climate change and variability -The role of Arctic cryosphere in the global change -Change in terrestrial ecosystem of pan-Arctic and its effect on climate -Studies on greenhouse gas cycles in the Arctic and their responses to climate change -Atmospheric studies on Arctic change and its global impacts -Ecosystem studies of the Arctic ocean declining Sea ice -Projection of Arctic Sea ice responding to availability of Arctic sea route (* ** ***) *Changes in the Arctic ocean and mechanisms on catastrophic reduction of Arctic sea ice cover **Coordinated observational and modeling studies on the basic structure and variability of the Arctic sea ice-ocean system ***Sea ice prediction and construction of ice navigation support system for the Arctic sea route. Although GRENE Arctic project aims to product scientific contribution in a concentrated program during 2011-2016, Japanese Arctic research community established Japan Consortium for Arctic Environmental Research (JCAR) in May

  5. Animistic pragmatism and native ways of knowing: adaptive strategies for overcoming the struggle for food in the sub-Arctic

    Directory of Open Access Journals (Sweden)

    Raymond Anthony

    2013-08-01

    Full Text Available Background. Subsistence norms are part of the “ecosophy” or ecological philosophy of Alaska Native Peoples in the sub-Arctic, such as the Inupiat of Seward Peninsula. This kind of animistic pragmatism is a special source of practical wisdom that spans over thousands of years and which has been instrumental in the Iñupiat’s struggle to survive and thrive in harsh and evolving environments. Objective. I hope to show how narrative in relationship to the “ecosophy” of Alaska Native peoples can help to promote a more ecological orientation to address food insecurity in rural communities in Alaska. Alaska Native ecosophy recommends central values and virtues necessary to help address concerns in Alaska’s rural communities. Design. Here, I will tease out the nature of this “ecosophy” in terms of animistic pragmatism and then show why this form of pragmatism can be instrumental for problematizing multi-scalar, intergenerational, uncertain and complex environmental challenges like food security. Results. Native elders have been the embodiment of trans-generational distributed cognition,1 for example, collective memory, norms, information, knowledge, technical skills and experimental adaptive strategies. They are human “supercomputers,” historical epistemologists and moral philosophers of a sort who use narrative, a form of moral testimony, to help their communities face challenges and seize opportunities in the wake of an ever-changing landscape. Conclusions. The “ecosophy” of the Iñupiat of Seward Peninsula offers examples of “focal practices”, which are essential for environmental education. These focal practices instil key virtues, namely humility, gratitude, self-reliance, attentiveness, responsibility and responsiveness, that are necessary for subsistence living.

  6. Arctic Terrestrial Biodiversity Monitoring Plan

    DEFF Research Database (Denmark)

    Christensen, Tom; Payne, J.; Doyle, M.;

    The Conservation of Arctic Flora and Fauna (CAFF), the biodiversity working group of the Arctic Council, established the Circumpolar Biodiversity Monitoring Program (CBMP) to address the need for coordinated and standardized monitoring of Arctic environments. The CBMP includes an international...... on developing and implementing long-term plans for monitoring the integrity of Arctic biomes: terrestrial, marine, freshwater, and coastal (under development) environments. The CBMP Terrestrial Expert Monitoring Group (CBMP-TEMG) has developed the Arctic Terrestrial Biodiversity Monitoring Plan (CBMP......-Terrestrial Plan/the Plan) as the framework for coordinated, long-term Arctic terrestrial biodiversity monitoring. The goal of the CBMP-Terrestrial Plan is to improve the collective ability of Arctic traditional knowledge (TK) holders, northern communities, and scientists to detect, understand and report on long...

  7. Effect of feeding selectivity on the transfer of methylmercury through experimental marine food chains.

    Science.gov (United States)

    Zhang, Peng; Sun, Jingxian; Chen, Jieru; Wei, Jie; Zhao, Wen; Liu, Qing; Sun, Huiling

    2013-08-01

    The present study established an experimental marine food chain of three levels (microalgae → zooplankton → fish) to investigate the effect of feeding selectivity on the transfer of methylmercury (MeHg) through the food chain. Total Hg concentrations in Chlorella sp., Nitzschia closterium and Isochrysis galbana exposed to 1 μg L(-1) MeHg for three days were 27.91, 32.74 and 40.03 μg g(-1) respectively and were significantly different (p Moina mongolica and Artemia sp. primarily selected Chlorella sp. as the sole diet, though the Artemia sp. partly grazed on I. galbana as well. Harpacticus uniremis, however, preferred to graze N. closterium and I. galbana and avoided Chlorella sp. The varying concentration of Hg in the microalgae species as well as the selectivity of zooplankton to the algal diet resulted in varying Hg accumulation in three zooplankton species (M. mongolica P. olivaceus > F. rubripes with total Hg concentrations of 0.0042, 0.0031 and 0.0020 μg g(-1), respectively). These investigations suggested feeding selectivity plays a key role in the transfer of MeHg along marine food chains. PMID:23702096

  8. Influence of dispersants on petroleum bioavailability in a marine food chain

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, M.; Tjeerdema, R. [Univ. of California, Santa Cruz, CA (United States). Dept. of Chemistry and Biochemistry; Sowby, M. [California Dept. of Fish and Game, Sacramento, CA (United States)

    1995-12-31

    When crude oil is accidentally released into the ocean it threatens many levels of marine life. Intervention, in the form of chemical dispersing agents, may alter the normal behavior of petroleum hydrocarbons (PH) by increasing their functional water solubility and the extent of their exposure to sub-surface marine organisms. Further, the dispersing agent may modify bioavailability as a result of altered interactions between dispersed PH droplets and organismal cell membranes, To date, little information exists on the sub-lethal effects of dispersants and factors modifying their role in the bioavailability and disposition of PH in marine food chains. The objective of the current research was to determine the impact of dispersing agents on PH bioavailability to primary levels of a marine food chain. Uptake, bioaccumulation, deputation, and metabolic transformation of a model PH, {sup 14}C-naphthalene, were measured and compared for dispersed Prudhoe Bay Crude Oil (PBCO) vs. undispersed preparations of the water-accommodated fractions (WAF) of PBCO at two salinities (22 and 34 ppt) employing Isochrysis galbana, a primary producer, and Brachionus plicatilis, a primary consumer. Fractionation and identification of metabolites was done by HPLC co-chromatography with analytical standards, and quantitation was done by liquid scintillation counting. GC-FID characterization of WAF and dispersed oil preparations shows higher concentrations of petroleum hydrocarbons and a greater number of individual constituents in the dispersed oil preparations. However, short term (eight hour) and long term (two week) static exposure studies indicate the uptake of{sup 14}C-naphthalene from WAF preparations is inhibited by up to 50% from dispersed oil preparations. Results of comparative static and flow-through chamber exposure studies will be presented.

  9. Influence of trophic position on organochlorine concentrations and compositional patterns in a marine food web.

    Science.gov (United States)

    Ruus, Anders; Ugland, Karl Inne; Skaare, Janneche Utne

    2002-11-01

    The accumulation of polychlorinated biphenyls (PCBs), DDTs (p,p'-DDT [1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane], o,p'-DDT [1,1,1-trichloro-2-(2-chlorophenyl)-2-(4-chlorophenyl)ethane], p,p'-DDD [1,1,-dichloro-2,2-bis(4-chlorophenyl)ethane], o.p'-DDD [1,1-dichloro-2-(2-chlorophenyl)-2-(4-chlorophenyl)ethane], and p,p'-DDE [1,1-dichloro-2,2-bis(4-chlorophenyl)ethene]), chlordanes (trans-chlordane, cis-chlordane, trans-nonachlor, cis-nonachlor and oxychlordane), hexachlorocyclohexanes (alpha-, beta-, and gamma-isomers), hexachlorobenzene, and mirex was investigated in a marine food web from southeastern Norway. The food web consisted of the polychaete Nereis diversicolor, lesser sandeel (Ammodytes tobianus), three species of gobys (Gobiusculus flavescens, Pomatoschistus sp., and Gobius niger), bullrout (Myoxocephalus scorpius), cod (Gadus morhua), herring gull (Larus argentatus), and harbor seal (Phoca vitulina). The results show that interspecies differences in organochlorine (OC) compositional patterns in the food web depend on several factors (allometric, biochemical, physical, and physicochemical) specific to both the chemicals and the organisms. The importance of dietary accumulation and metabolic capacity increases toward higher trophic levels, while the OC patterns are to a larger extent determined by the lipophilicity and water solubility of the compounds at lower trophic levels. Furthermore, stable nitrogen isotopes provided a continuous measure of trophic position, rendering us capable of quantifying the increases in the concentrations of sigma PCB, sigma dichorodiphenyltrichloroethane (DDT), and sigma chlordane (CHL) and the percentages of highly chlorinated PCBs through the food web. The information provided may be important for future modeling of the fate of organochlorine contaminants in marine food webs. PMID:12389914

  10. Physico-chemical properties, oxidative stability and non-enzymatic browning in marine phospholipid emulsions and their use in food applications

    DEFF Research Database (Denmark)

    Lu, Henna Fung Sieng

    Marine phospholipids (PL) contain a high level of eicosapentaenoic acids (EPA) and docosahexaenoic acids (DHA), which have documented beneficial effect on human health. In addition, marine PL are more advantageous than crude or refined fish oils. Marine PL are more resistant to oxidation, provide...... of current marine PL that was used for emulsion preparation and food application. In addition, the oxidative stability and sensory quality of marine PL fortified products varied depending on the quality and source of marine PL used for fortification. Although the attempts to incorporate marine PL into food...... better bioavailability and ability to form liposomes. All these unique properties of marine PL make them an attractive choice as ingredients for food fortification. Nowadays, a wide range of food products fortified with n-3 triglycerides (TAG) are available worldwide. However, the feasibility of using...

  11. SCICEX: Submarine Arctic Science Program

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Submarine Arctic Science Program, SCICEX, is a federal interagency collaboration among the operational Navy, research agencies, and the marine research...

  12. Spatial and temporal variation of an ice-adapted predator's feeding ecology in a changing Arctic marine ecosystem.

    Science.gov (United States)

    Yurkowski, David J; Ferguson, Steven H; Semeniuk, Christina A D; Brown, Tanya M; Muir, Derek C G; Fisk, Aaron T

    2016-03-01

    Spatial and temporal variation can confound interpretations of relationships within and between species in terms of diet composition, niche size, and trophic position (TP). The cause of dietary variation within species is commonly an ontogenetic niche shift, which is a key dynamic influencing community structure. We quantified spatial and temporal variations in ringed seal (Pusa hispida) diet, niche size, and TP during ontogeny across the Arctic-a rapidly changing ecosystem. Stable carbon and nitrogen isotope analysis was performed on 558 liver and 630 muscle samples from ringed seals and on likely prey species from five locations ranging from the High to the Low Arctic. A modest ontogenetic diet shift occurred, with adult ringed seals consuming more forage fish (approximately 80 versus 60 %) and having a higher TP than subadults, which generally decreased with latitude. However, the degree of shift varied spatially, with adults in the High Arctic presenting a more restricted niche size and consuming more Arctic cod (Boreogadus saida) than subadults (87 versus 44 %) and adults at the lowest latitude (29 %). The TPs of adult and subadult ringed seals generally decreased with latitude (4.7-3.3), which was mainly driven by greater complexity in trophic structure within the zooplankton communities. Adult isotopic niche size increased over time, likely due to the recent circumpolar increases in subarctic forage fish distribution and abundance. Given the spatial and temporal variability in ringed seal foraging ecology, ringed seals exhibit dietary plasticity as a species, suggesting adaptability in terms of their diet to climate change. PMID:26210748

  13. Bioaccumulation of radiocaesium in Arctic seals

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, JoLynn; Wolkers, Hans; Andersen, Magnus; Rissanen, Kristina

    2002-12-01

    Seals are high trophic level feeders that bioaccumulate many contaminants to a greater degree than most lower trophic level organisms. Their trophic status in the marine food web and wide-spread distribution make seals useful sentinels of arctic environmental change. The purpose of this investigation is to document the levels and bioaccumulation potential of radiocaesium in high latitude seal species for which data have not previously been available. The study was carried out on harp, ringed, and bearded seals caught north of the island archipelago of Svalbard (82 deg. N) in 1999. The results are then compared with previous studies in order to elucidate factors responsible for bioaccumulation in Arctic seals. Concentrations of {sup 137}Cs were determined in muscle, liver and kidney samples from a total of 10 juvenile and one adult seal. The mean concentration in muscle samples for all animals was 0.23{+-}0.045 Bq/kg f.w. {sup 137}Cs concentrations in both liver and kidney samples were near detection limits ({approx}0.2 Bq/kg f.w.). The results are consistent with previous studies indicating low levels of radiocaesium in Arctic seals in response to a long term trend of decreasing levels of {sup 137}Cs in the Barents Sea region. Bioconcentration factors (BCFs) estimated for seals from NE Svalbard are low, ranging from 34 to 130. Comparing these values with reported BCFs for Greenland seals from other sectors of the European Arctic, we suggest that the combination of physiological and ecological factors on radiocaesium bioaccumulation is comparable among different Arctic seal populations. The application of this work to Arctic monitoring and assessment programs is discussed.

  14. Influence of dispersants on trophic transfer of petroleum hydrocarbons in a marine food chain

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, M. F.; Schwartz, G. J. B.; Singaram, S.; Tjeerdema, R. S. [California Univ., Santa Cruz, CA (United States). Dept. of Chemistry; Mielbrecht, E. E. [California Univ., Santa Cruz, CA (United States). Inst. of Marine Sciences; Sowby, M. L. [California State Dept. of Fish and Game, Sacramento, CA (United States)

    1997-10-01

    Experiments were conducted to determine the impact of dispersing agents on petroleum hydrocarbons (PH) bioavailability and trophic transfer in primary levels of a marine food chain. Uptake, bioaccumulation and metabolic transformation of a model PH, ({sup 1}4C)naphthalene, were measured and compared with Prudhoe Bay Crude Oil (PBCO) dispersed with Corexit 9527, and undispersed preparations of PBCO. The model food chain consisted of a primary algae producer and a primary rotifer consumer. Results showed that uptake of naphthalene increased significantly in the presence of a dispersant in algae. A significant increase in uptake was also recorded in rotifers via trophic transfer. Trophic transfer played a significant, sometimes even dominant, role in uptake and bioaccumulation. 27 refs., 6 figs.

  15. Influence of dispersants on trophic transfer of petroleum hydrocarbons in a marine food chain

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, M.; Tjeerdema, R. [Univ. of California, Santa Cruz, CA (United States). Dept. of Chemistry and Biochemistry; Sowby, M. [California Dept. of Fish and Game, Sacramento, CA (United States)

    1995-12-31

    When crude oil is accidentally released into the ocean, it threatens many levels of marine life. Intervention, in the form of chemical dispersing agents, alters the normal behavior of petroleum hydrocarbons (PH) by increasing their functional water solubility and the extent of their exposure to sub-surface organisms. Dispersing agents may modify bioavailability as a result of altered interactions between dispersed PH droplets and organismal cell membranes.The objective of this research was to determine the impact of dispersing agents on PH bioavailability and trophic transfer in primary levels of a marine food chain. Uptake, bioaccumulation, depuration, and metabolic transformation of a model PH, {sup 14}C-naphthalene, were measured and compared for Prudhoe Bay Crude Oil (PBCO) dispersed with Corexit 9527 and undispersed preparations of the water-accommodated fractions (WAF) of PBCO at two salinities and temperatures. The model food chain consisted of Isochrysis galbana and Brachionus plicatilis. Direct aqueous exposure was compared with combined aqueous and dietary exposure. Fractionation and identification of metabolites was done by HPLC co-chromatography with analytical standards, and quantitation was done by liquid scintillation counting. GC-FID characterization of WAF and dispersed oil (DO) preparations shows higher concentrations of petroleum hydrocarbons and a greater number of individual constituents in the dispersed oil preparations.

  16. An evaluation of underlying mechanisms for “fishing down marine food webs”

    Institute of Scientific and Technical Information of China (English)

    DING Qi; CHEN Xinjun; YU Wei; TIAN Siquan; CHEN Yong

    2016-01-01

    Since the concept of “fishing down marine food webs” was first proposed in 1998, mean trophic level of fisheries landings (MTL) has become one of the most widely used indicators to assess the impacts of fishing on the integrity of marine ecosystem and guide the policy development by many management agencies. Recent studies suggest that understanding underlying causes for changes in MTL is vital for an appropriate use of MTL as an indicator of fishery sustainability. Based on the landing data compiled by Food and Agriculture Organization (FAO) and trophic information of relevant species in Fishbase, we evaluated MTL trends in 14 FAO fishing areas and analyzed catches of upper and lower trophic level groups under different trends of MTL and found that both the cases of a recovered MTL trend and a generally increasing MTL trend could be accompanied by decreasing catches of lower trophic level species. Further, community structure and exploitation history should be considered in using MTL after excluding species with trophic levels lower than 3.25 to distinguish “fishing-through” from “fishing-down”. We conclude that MTL used as an indicator to measure fishery sustainability can benefit from a full consideration of both upper and lower trophic level species and masking effects of community structure and exploitation history.

  17. Arctic Alaska’s Lower Cretaceous (Hauterivian and Barremian) mudstone succession—Linking lithofacies, texture, and geochemistry to marine processes

    Science.gov (United States)

    Keller, Margaret A.; Macquaker, Joe H.S.

    2015-01-01

    We present new images and descriptions of the lithofacies and organic facies of the pebble shale unit and lower part of the Hue Shale (Lower Cretaceous) of Arctic Alaska at a high magnification that illustrates their textural characteristics. Our aims were to describe and determine the distribution of facies in these petroleum source rocks and to identify the processes that formed them. We sampled at high-resolution and applied new petrographic techniques combined with scanning electron microscopy and geochemical analyses to samples collected from three widely spaced sections—located in exposures along the Canning River and continuous core from the Mikkelsen Bay State 1 and Orion 1 wells.

  18. A biomarker record of Lake El'gygytgyn, Far East Russian Arctic: investigating sources of organic matter and carbon cycling during marine isotope stages 1–3

    Directory of Open Access Journals (Sweden)

    A. R. Holland

    2013-01-01

    Full Text Available Arctic paleoenvironmental archives serve as sensitive recorders of past climate change. Lake El'gygytgyn (Far East Russian Arctic is a high-latitude crater impact lake that contains a continuous sediment record influenced by neither glaciation nor glacial erosion since the time of impact 3.58 Ma ago. Prior research on sediments collected from Lake El'gygytgyn suggest times of permanent ice cover and anoxia corresponding to global glacial intervals, during which the sediments are laminated and are characterized by the co-occurrence of high total organic carbon, microscopic magnetite grains that show etching and dissolution, and negative excursions in bulk sediment organic matter carbon isotope (δ13C values. Here we investigate the abundance and carbon isotopic composition of lipid biomarkers recovered from Lake El'gygytgyn sediments spanning marine isotope stages 1–3 to identify key sources of organic matter (OM to lake sediments, to establish which OM sources drive the negative δ13C excursion exhibited by bulk sediment OM, and to explore if there are molecular and isotopic signatures of anoxia in the lake during glaciation. We find that during marine isotope stages 1–3, direct evidence for water column anoxia is lacking. A ~4‰ negative excursion in bulk sediment δ13C values during the Local Last Glacial Maximum (LLGM is accompanied by more protracted, higher magnitude negative excursions in n-alkanoic acid and n-alkanol δ13C values that begin 20 kyr in advance of the LLGM. In contrast, n-alkanes and the C30 n-alkanoic acid do not exhibit a negative δ13C excursion at this time. Our results indicate that the C24, C26 and C28 n-alkanoic acids do not derive entirely from terrestrial OM sources, while the C30 n-alkanoic acid at Lake El'gygytgyn is a robust indicator of terrestrial OM contributions. Overall, our results strongly support the presence of a nutrient-poor water column, which is mostly isolated from atmospheric carbon dioxide

  19. Correlates between feeding ecology and mercury levels in historical and modern arctic foxes (Vulpes lagopus.

    Directory of Open Access Journals (Sweden)

    Natalia Bocharova

    Full Text Available Changes in concentration of pollutants and pathogen distribution can vary among ecotypes (e.g. marine versus terrestrial food resources. This may have important implications for the animals that reside within them. We examined 1 canid pathogen presence in an endangered arctic fox (Vulpes lagopus population and 2 relative total mercury (THg level as a function of ecotype ('coastal' or 'inland' for arctic foxes to test whether the presence of pathogens or heavy metal concentration correlate with population health. The Bering Sea populations on Bering and Mednyi Islands were compared to Icelandic arctic fox populations with respect to inland and coastal ecotypes. Serological and DNA based pathogen screening techniques were used to examine arctic foxes for pathogens. THg was measured by atomic absorption spectrometry from hair samples of historical and modern collected arctic foxes and samples from their prey species (hair and internal organs. Presence of pathogens did not correlate with population decline from Mednyi Island. However, THg concentration correlated strongly with ecotype and was reflected in the THg concentrations detected in available food sources in each ecotype. The highest concentration of THg was found in ecotypes where foxes depended on marine vertebrates for food. Exclusively inland ecotypes had low THg concentrations. The results suggest that absolute exposure to heavy metals may be less important than the feeding ecology and feeding opportunities of top predators such as arctic foxes which may in turn influence population health and stability. A higher risk to wildlife of heavy metal exposure correlates with feeding strategies that rely primarily on a marine based diet.

  20. Risk assessment of bioaccumulation in the food webs of two marine AMOEBE species: common tern and harbor seal

    NARCIS (Netherlands)

    Jongbloed RH; Mensink BJWG; Vethaak AD; Luttik R; Rijksinstituut voor Kust en Zee; ACT; RIKZ

    1995-01-01

    A model has been developed for calculating Maximum Permissible Concentrations (MPCs) in water for chemicals accumulating in food webs of sea birds and mammals. Calculations are carried out for two marine AMOEBE species: common tern (Sterna hirundo) and harbor seal (Phoca vitulina), and five chemical

  1. Out On The Ice (OOTI): Studies of Bromine Monoxide (BrO) and ozone (O3) in the Arctic and Sub-Arctic Marine Boundary Layer by Multiple Axis Differential Optical Absorption Spectroscopy (MAXDOAS): Local Emissions or Transport Processes?

    Science.gov (United States)

    Netcheva, S.; Bottenheim, J. W.; Staebler, R. M.; Steffen, A.

    2009-12-01

    BrO is an important tropospheric trace gas species in the marine boundary layer with potentially harmful effects on the polar environment. It changes the atmospheric oxidizing capacity by altering normally O3 dominating oxidation pathways via a series of autocatalytic heterogeneous O3 destroying reactions. There have been many reports of elevated BrO concentrations in the Polar atmospheric boundary layer by ground based and satellite DOAS measurements since the first positive identification by Hausmann and Platt in 1994 at Alert, Canada. Satellite acquired data revealed that enhanced tropospheric BrO concentrations in the spring are a widespread, reoccurring phenomena in the polar regions, and that they are possibly linked to the spatial distribution of first year sea ice. While the main source of bromine in the marine boundary layer is clearly sea salt, the processes of migration from the ocean surface to the air, and mechanisms of activation, are not fully understood. Conceivably these processes operate on a much smaller spatial scale than satellite measurements suggest In a study under the OASIS-Canada program funded by the Canadian Federal Program Office for the International Polar Year, ground based measurements of BrO and O3 over the ice of the Arctic Ocean and Hudson Bay, were compared with concurrent BrO satellite measurements, ice conditions, back trajectory and meteorological surface analyses to identify BrO source regions and to estimate the influence of transport on the evolution of enhanced BrO events. Conducting measurements directly on ice surfaces enabled us to improve the understanding of the chemistry involved because we could directly target reactive halogen emission and try to assess the role of various ocean surfaces during halogen activation and propagation. Some of the recorded events were characterised by fast decreases of O3 during the night, which clearly indicates transport rather than local chemistry. Other events required more

  2. Ecology of conflict: marine food supply affects human-wildlife interactions on land

    Science.gov (United States)

    Artelle, Kyle A.; Anderson, Sean C.; Reynolds, John D.; Cooper, Andrew B.; Paquet, Paul C.; Darimont, Chris T.

    2016-01-01

    Human-wildlife conflicts impose considerable costs to people and wildlife worldwide. Most research focuses on proximate causes, offering limited generalizable understanding of ultimate drivers. We tested three competing hypotheses (problem individuals, regional population saturation, limited food supply) that relate to underlying processes of human-grizzly bear (Ursus arctos horribilis) conflict, using data from British Columbia, Canada, between 1960–2014. We found most support for the limited food supply hypothesis: in bear populations that feed on spawning salmon (Oncorhynchus spp.), the annual number of bears/km2 killed due to conflicts with humans increased by an average of 20% (6–32% [95% CI]) for each 50% decrease in annual salmon biomass. Furthermore, we found that across all bear populations (with or without access to salmon), 81% of attacks on humans and 82% of conflict kills occurred after the approximate onset of hyperphagia (July 1st), a period of intense caloric demand. Contrary to practices by many management agencies, conflict frequency was not reduced by hunting or removal of problem individuals. Our finding that a marine resource affects terrestrial conflict suggests that evidence-based policy for reducing harm to wildlife and humans requires not only insight into ultimate drivers of conflict, but also management that spans ecosystem and jurisdictional boundaries. PMID:27185189

  3. Ecology of conflict: marine food supply affects human-wildlife interactions on land.

    Science.gov (United States)

    Artelle, Kyle A; Anderson, Sean C; Reynolds, John D; Cooper, Andrew B; Paquet, Paul C; Darimont, Chris T

    2016-01-01

    Human-wildlife conflicts impose considerable costs to people and wildlife worldwide. Most research focuses on proximate causes, offering limited generalizable understanding of ultimate drivers. We tested three competing hypotheses (problem individuals, regional population saturation, limited food supply) that relate to underlying processes of human-grizzly bear (Ursus arctos horribilis) conflict, using data from British Columbia, Canada, between 1960-2014. We found most support for the limited food supply hypothesis: in bear populations that feed on spawning salmon (Oncorhynchus spp.), the annual number of bears/km(2) killed due to conflicts with humans increased by an average of 20% (6-32% [95% CI]) for each 50% decrease in annual salmon biomass. Furthermore, we found that across all bear populations (with or without access to salmon), 81% of attacks on humans and 82% of conflict kills occurred after the approximate onset of hyperphagia (July 1(st)), a period of intense caloric demand. Contrary to practices by many management agencies, conflict frequency was not reduced by hunting or removal of problem individuals. Our finding that a marine resource affects terrestrial conflict suggests that evidence-based policy for reducing harm to wildlife and humans requires not only insight into ultimate drivers of conflict, but also management that spans ecosystem and jurisdictional boundaries. PMID:27185189

  4. PMEL EcoFOCI Early Arctic Data, 1986-1991

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Pacific Marine Environmental Laboratory (PMEL) Fisheries-Oceanography Cooperative Investigations (FOCI) Early Arctic Data, 1987 - 1991

  5. Habitat traits and food availability determine the response of marine invertebrates to ocean acidification.

    Science.gov (United States)

    Pansch, Christian; Schaub, Iris; Havenhand, Jonathan; Wahl, Martin

    2014-03-01

    Energy availability and local adaptation are major components in mediating the effects of ocean acidification (OA) on marine species. In a long-term study, we investigated the effects of food availability and elevated pCO2 (ca. 400, 1000 and 3000 μatm) on growth of newly settled Amphibalanus (Balanus) improvisus to reproduction, and on their offspring. We also compared two different populations, which were presumed to differ in their sensitivity to pCO2 due to differing habitat conditions: Kiel Fjord, Germany (Western Baltic Sea) with naturally strong pCO2 fluctuations, and the Tjärnö Archipelago, Sweden (Skagerrak) with far lower fluctuations. Over 20 weeks, survival, growth, reproduction and shell strength of Kiel barnacles were all unaffected by elevated pCO2 , regardless of food availability. Moulting frequency and shell corrosion increased with increasing pCO2 in adults. Larval development and juvenile growth of the F1 generation were tolerant to increased pCO2 , irrespective of parental treatment. In contrast, elevated pCO2 had a strong negative impact on survival of Tjärnö barnacles. Specimens from this population were able to withstand moderate levels of elevated pCO2 over 5 weeks when food was plentiful but showed reduced growth under food limitation. Severe levels of elevated pCO2 negatively impacted growth of Tjärnö barnacles in both food treatments. We demonstrate a conspicuously higher tolerance to elevated pCO2 in Kiel barnacles than in Tjärnö barnacles. This tolerance was carried over from adults to their offspring. Our findings indicate that populations from fluctuating pCO2 environments are more tolerant to elevated pCO2 than populations from more stable pCO2 habitats. We furthermore provide evidence that energy availability can mediate the ability of barnacles to withstand moderate CO2 stress. Considering the high tolerance of Kiel specimens and the possibility to adapt over many generations, near future OA alone does not seem to

  6. Effects of pyrene exposure and temperature on early development of two co-existing Arctic copepods

    DEFF Research Database (Denmark)

    Grenvald, Julie Cornelius; Nielsen, Torkel Gissel; Hjorth, Morten

    2013-01-01

    Oil exploration is expected to increase in the near future in Western Greenland. At present, effects of exposure to oil compounds on early life-stages of the ecologically important Calanus spp. are unknown. We investigated the effects of the oil compound pyrene, on egg hatching and naupliar...... to pyrene from an oil spill may reduce the standing stock of Calanus, which can lead to less energy available to higher trophic levels in the Arctic marine food web...

  7. Technical Note: Constraining stable carbon isotope values of microphytobenthos (C3 photosynthesis) in the Arctic for application to food web studies

    OpenAIRE

    Oxtoby, L. E.; Mathis, J. T.; Juranek, L. W.; M. J. Wooller

    2013-01-01

    Microphytobenthos (MPB) tends to be omitted as a possible carbon source to higher trophic level consumers in high latitude marine food web models that use stable isotopes. Here, we used previously published relationships relating the concentration of aqueous carbon dioxide ([CO2]aq), the stable carbon isotopic composition of dissolved inorganic carbon (DIC) (δ13CDIC), and algal growth rates (μ) to estimate the stable carbon isotop...

  8. Marine Mammals.

    Science.gov (United States)

    Meith, Nikki

    Marine mammals have not only fascinated and inspired human beings for thousands of years, but they also support a big business by providing flesh for sea-borne factories, sustaining Arctic lifestyles and traditions, and attracting tourists to ocean aquaria. While they are being harpooned, bludgeoned, shot, netted, and trained to jump through…

  9. 76 FR 38666 - Food and Drug Administration (FDA) and Marine Environmental Sciences Consortium/Dauphin Island...

    Science.gov (United States)

    2011-07-01

    ... Nutrition (CFSAN) and the Marine Environmental Sciences Consortium/Dauphin Island Sea Lab (DISL). The goal... Marine Environmental Science Consortium-Dauphin Island Sea Lab (DISL) will greatly contribute to FDA's... Objectives FDA Gulf Coast Seafood Laboratory (GCSL) and the Marine Environmental Science Consortium of...

  10. Transcriptome Survey of a Marine Food Fish: Asian Seabass (Lates calcarifer

    Directory of Open Access Journals (Sweden)

    Natascha M. Thevasagayam

    2015-06-01

    Full Text Available The Asian seabass (or barramundi; Lates calcarifer is a marine teleost and a popular food fish in Southeast Asia and Australia. To date, comprehensive genome and transcriptome sequence information has not been available for this species in public repositories. Here, we report a comprehensive de novo transcriptome assembly of the Asian seabass. These data will be useful for the development of molecular tools for use in aquaculture of Asian seabass as well as a resource for genome annotation. The transcriptome was obtained from sequences generated from organs of multiple individuals using three different next-generation sequencing platforms (454-FLX Titanium, SOLiD 3+, and paired-end Illumina HiSeq 2000. The assembled transcriptome contains >80% of the expected protein-coding loci, with 58% of these represented by a predicted full-length cDNA sequence when compared to the available Nile tilapia RefSeq dataset. Detailed descriptions of the various steps involved in sequencing and assembling a transcriptome are provided to serve as a helpful guide for transcriptome projects involving de novo assembly of short sequence reads for non-model teleosts or any species of interest.

  11. Selecting indicator portfolios for marine species and food webs: a Puget sound case study.

    Directory of Open Access Journals (Sweden)

    Jessi Kershner

    Full Text Available Ecosystem-based management (EBM has emerged as a promising approach for maintaining the benefits humans want and need from the ocean, yet concrete approaches for implementing EBM remain scarce. A key challenge lies in the development of indicators that can provide useful information on ecosystem status and trends, and assess progress towards management goals. In this paper, we describe a generalized framework for the methodical and transparent selection of ecosystem indicators. We apply the framework to the second largest estuary in the United States - Puget Sound, Washington - where one of the most advanced EBM processes is currently underway. Rather than introduce a new method, this paper integrates a variety of familiar approaches into one step-by-step approach that will lead to more consistent and reliable reporting on ecosystem condition. Importantly, we demonstrate how a framework linking indicators to policy goals, as well as a clearly defined indicator evaluation and scoring process, can result in a portfolio of useful and complementary indicators based on the needs of different users (e.g., policy makers and scientists. Although the set of indicators described in this paper is specific to marine species and food webs, we provide a general approach that could be applied to any set of management objectives or ecological system.

  12. Modeling bioaccumulation and biomagnification of nonylphenol and its ethoxylates in estuarine-marine food chains.

    Science.gov (United States)

    Korsman, John C; Schipper, Aafke M; de Vos, Martine G; van den Heuvel-Greve, Martine J; Vethaak, A Dick; de Voogt, Pim; Hendriks, A Jan

    2015-11-01

    There are several studies on bioaccumulation and biomagnification of nonylphenol (NP) and its ethoxylates (NPEOs), but their toxico-kinetic mechanisms remain unclear. In the present investigation, we explored the accumulation of NP and NPEOs in estuarine-marine food chains with a bioaccumulation model comprising five trophic levels. Using this model, we estimated uptake and elimination rate constants for NPEOs based on the organisms' weight and lipid content and the chemicals' Kow. Further, we calculated accumulation factors for NP and NPEOs, including biota-sediment accumulation factors (BSAF) and biomagnification factors (BMF), and compared these to independent field measurements collected in the Western Scheldt estuary in The Netherlands and field data reported in the literature. The estimated BSAF values for NP and total NPEOs were below 1 for all trophic levels. The estimated BMF values were around 1 for all trophic levels except for the highest level (carnivorous mammals and birds). For this trophic level, the estimated BMF value varied between 0.1 and 2.4, depending on the biotransformation capacity. For all trophic levels, except primary producers, the accumulation estimates that accounted for biotransformation of NPEOs into NP were closer to the field data than model estimates that did not include biotransformation, indicating that NP formation by biotransformation of NPEOs might occur in organisms. PMID:26026901

  13. Global patterns in ecological indicators of marine food webs: a modelling approach.

    Directory of Open Access Journals (Sweden)

    Johanna Jacomina Heymans

    Full Text Available BACKGROUND: Ecological attributes estimated from food web models have the potential to be indicators of good environmental status given their capabilities to describe redundancy, food web changes, and sensitivity to fishing. They can be used as a baseline to show how they might be modified in the future with human impacts such as climate change, acidification, eutrophication, or overfishing. METHODOLOGY: In this study ecological network analysis indicators of 105 marine food web models were tested for variation with traits such as ecosystem type, latitude, ocean basin, depth, size, time period, and exploitation state, whilst also considering structural properties of the models such as number of linkages, number of living functional groups or total number of functional groups as covariate factors. PRINCIPAL FINDINGS: Eight indicators were robust to model construction: relative ascendency; relative overhead; redundancy; total systems throughput (TST; primary production/TST; consumption/TST; export/TST; and total biomass of the community. Large-scale differences were seen in the ecosystems of the Atlantic and Pacific Oceans, with the Western Atlantic being more complex with an increased ability to mitigate impacts, while the Eastern Atlantic showed lower internal complexity. In addition, the Eastern Pacific was less organised than the Eastern Atlantic although both of these systems had increased primary production as eastern boundary current systems. Differences by ecosystem type highlighted coral reefs as having the largest energy flow and total biomass per unit of surface, while lagoons, estuaries, and bays had lower transfer efficiencies and higher recycling. These differences prevailed over time, although some traits changed with fishing intensity. Keystone groups were mainly higher trophic level species with mostly top-down effects, while structural/dominant groups were mainly lower trophic level groups (benthic primary producers such as

  14. Global Patterns in Ecological Indicators of Marine Food Webs: A Modelling Approach

    Science.gov (United States)

    Heymans, Johanna Jacomina; Coll, Marta; Libralato, Simone; Morissette, Lyne; Christensen, Villy

    2014-01-01

    Background Ecological attributes estimated from food web models have the potential to be indicators of good environmental status given their capabilities to describe redundancy, food web changes, and sensitivity to fishing. They can be used as a baseline to show how they might be modified in the future with human impacts such as climate change, acidification, eutrophication, or overfishing. Methodology In this study ecological network analysis indicators of 105 marine food web models were tested for variation with traits such as ecosystem type, latitude, ocean basin, depth, size, time period, and exploitation state, whilst also considering structural properties of the models such as number of linkages, number of living functional groups or total number of functional groups as covariate factors. Principal findings Eight indicators were robust to model construction: relative ascendency; relative overhead; redundancy; total systems throughput (TST); primary production/TST; consumption/TST; export/TST; and total biomass of the community. Large-scale differences were seen in the ecosystems of the Atlantic and Pacific Oceans, with the Western Atlantic being more complex with an increased ability to mitigate impacts, while the Eastern Atlantic showed lower internal complexity. In addition, the Eastern Pacific was less organised than the Eastern Atlantic although both of these systems had increased primary production as eastern boundary current systems. Differences by ecosystem type highlighted coral reefs as having the largest energy flow and total biomass per unit of surface, while lagoons, estuaries, and bays had lower transfer efficiencies and higher recycling. These differences prevailed over time, although some traits changed with fishing intensity. Keystone groups were mainly higher trophic level species with mostly top-down effects, while structural/dominant groups were mainly lower trophic level groups (benthic primary producers such as seagrass and macroalgae

  15. The Northern Bering Sea: An Arctic Ecosystem in Change

    Science.gov (United States)

    Grebmeier, J. M.; Cooper, L. W.

    2004-12-01

    Arctic systems can be rich and diverse habitats for marine life in spite of the extreme cold environment. Benthic faunal populations and associated biogeochemical cycling processes are influenced by sea-ice extent, seawater hydrography (nutrients, salinity, temperature, currents), and water column production. Benthic organisms on the Arctic shelves and margins are long-term integrators of overlying water column processes. Because these organisms have adapted to living at cold extremes, it is reasonable to expect that these communities will be among the most susceptible to climate warming. Recent observations show that Arctic sea ice in the North American Arctic is melting and retreating northward earlier in the season and the timing of these events can have dramatic impacts on the biological system. Changes in overlying primary production, pelagic-benthic coupling, and benthic production and community structure can have cascading effects to higher trophic levels, particularly benthic feeders such as walruses, gray whales, and diving seaducks. Recent indicators of contemporary Arctic change in the northern Bering Sea include seawater warming and reduction in ice extent that coincide with our time-series studies of benthic clam population declines in the shallow northern Bering shelf in the 1990's. In addition, declines in benthic amphipod populations have also likely influenced the movement of feeding gray whales to areas north of Bering Strait during this same time period. Finally a potential consequence of seawater warming and reduced ice extent in the northern Bering Sea could be the northward movement of bottom feeding fish currently in the southern Bering Sea that prey on benthic fauna. This would increase the feeding pressure on the benthic prey base and enhance competition for this food source for benthic-feeding marine mammals and seabirds. This presentation will outline recent biological changes observed in the northern Bering Sea ecosystem as documented in

  16. 15N and 13C abundances in marine environments with emphasis on biogeochemical structure of food networks

    International Nuclear Information System (INIS)

    Distributions of δ15N and δ13C for biogenic substances in the Antarctic Ocean and in the Otsuchi River estuary in Japan were investigated to construct isotope biogeochemical framework for assessing marine ecosystems. The isotopic compositions of phytoplankton were particularly low in the Antarctic Ocean. High nitrate and CO2 concentrations in the surface sea waters, and the low light intensity seem to enhance the kinetic isotope fractionations that preferred the depletion of 15N and 13C in the algal body. A clear-cut linear relationship between animal δ15N and its trophic level was obtained in the Antarctic system. In the estuary, the variation of isotope ratios were principally governed by the mixing of land-derived organic matter, marine phytoplankton, and seagrasses. A food-chain effect of 15N enrichment was also confirmed. An isotopically ordered structure was presented for a marine estuarine ecosystem. The isotopic abundances in a food network vary mainly because of the variation in 15N and 13C contents of primary producers grown under different environmental conditions and because of the enrichment of 15N along food chains. (author)

  17. Animistic pragmatism and native ways of knowing: adaptive strategies for overcoming the struggle for food in the sub-Arctic

    OpenAIRE

    Anthony, Raymond

    2013-01-01

    Background. Subsistence norms are part of the ‘‘ecosophy’’ or ecological philosophy of Alaska Native Peoples in the sub-Arctic, such as the Inupiat of Seward Peninsula. This kind of animistic pragmatism is a special source of practical wisdom that spans over thousands of years and which has been instrumental in the In˜upiat’s struggle to survive and thrive in harsh and evolving environments. Objective. I hope to show how narrative in relationship to the ‘‘ecosophy’’ of Alaska Native peoples c...

  18. Transfer of Paralytic Shellfish Toxins via Marine Food Chains:A Simulated Experiment

    Institute of Scientific and Technical Information of China (English)

    ZHI-JUN TAN; TIAN YAN; PEN-CHENG YU; MING-JIANG ZHOU

    2007-01-01

    Objective To study the transfer of paralytic shellfish toxins(PST)using four simulated marine food chains:d8noflagellate Alexandrium tamarense→Artemia Anemia salina→Mysid shrimp Neomysis awatschensis;A.tamarense→N.awatschensis:A.tamarense→A.salina→Perch Lateolabrax japonicus;and A.tamarenae→L. japonicus. Methods The ingestion of A.tamarenge.a producer of PST, by L. japonicus,N.awatschensis,and A.salina was first confirmed by microscopic observation of A.tamarense cells in the intestine samples of the three different organisms,and by the analysis of Chl.a levels in the samples.Toxin accumulation in L.japonicus and N.awatschensis directly from the feeding on A.tamarense 8r indirectly through the vector of A.salina was then studied.The toxicity of samples was measured using the AOAC mouse bioassay method,and the toxin content and profile of A.tamarense were analyzed by the HPLC method.Results Both A.salina and N.nwatschensis could ingest A.tamarense cells.However,the ingestion capability of A.salina exceeded that of N.L. japonicus.N.awatschensis and A.salina by microscopic observation.Therefore,the three organisms could ingest A.tamarense cells directly.A.salina could accumulate high content of PST,and the toxicity of A.salina in samples collected on of tested mice within 7 minutes,and the toxin content in artemia sample collected on the lst day was estimated to be 1.65×10-5 μg STX equal/individual.Toxin accumulation in L.japonicus and N.awatschensis directly from the feeding on A.tamarense or indirectly from the vector of A.salina was also studied.The mice injected with extracts from L.japonicus and N. awatschensis samples that accumulated PST either directly or indirectly showed PST intoxication symptoms,indicating that low levels of PST existed in these samples Conclusion Paralytic shellfish toxins can be transferred to L.japonicus,N.awatschensis,and A.salina from A.tamarense directly or indirectly via the food chains.

  19. Cephalopods as Vectors of Harmful Algal Bloom Toxins in Marine Food Webs

    Directory of Open Access Journals (Sweden)

    Rui Rosa

    2013-09-01

    Full Text Available Here we summarize the current knowledge on the transfer and accumulation of harmful algal bloom (HAB-related toxins in cephalopods (octopods, cuttlefishes and squids. These mollusks have been reported to accumulate several HAB-toxins, namely domoic acid (DA, and its isomers, saxitoxin (and its derivatives and palytoxin (and palytoxin-like compounds and, therefore, act as HAB-toxin vectors in marine food webs. Coastal octopods and cuttlefishes store considerably high levels of DA (amnesic shellfish toxin in several tissues, but mainly in the digestive gland (DG—the primary site of digestive absorption and intracellular digestion. Studies on the sub-cellular partitioning of DA in the soluble and insoluble fractions showed that nearly all DA (92.6% is found in the cytosol. This favors the trophic transfer of the toxins since cytosolic substances can be absorbed by predators with greater efficiency. The available information on the accumulation and tissue distribution of DA in squids (e.g., in stranded Humboldt squids, Dosidicus gigas is scarcer than in other cephalopod groups. Regarding paralytic shellfish toxins (PSTs, these organisms accumulate them at the greatest extent in DG >> kidneys > stomach > branchial hearts > posterior salivary glands > gills. Palytoxins are among the most toxic molecules identified and stranded octopods revealed high contamination levels, with ovatoxin (a palytoxin analogue reaching 971 μg kg−1 and palytoxin reaching 115 μg kg−1 (the regulatory limit for PlTXs is 30 μg kg−1 in shellfish. Although the impacts of HAB-toxins in cephalopod physiology are not as well understood as in fish species, similar effects are expected since they possess a complex nervous system and highly developed brain comparable to that of the vertebrates. Compared to bivalves, cephalopods represent a lower risk of shellfish poisoning in humans, since they are usually consumed eviscerated, with exception of traditional dishes from the

  20. Penguin eggshell membranes reflect homogeneity of mercury in the marine food web surrounding the Antarctic Peninsula

    International Nuclear Information System (INIS)

    Remote regions such as the Antarctic have become increasingly important for investigations into far-reaching anthropogenic impacts on the environment, most recently in regard to the global mercury cycle. Spatial patterns of mercury availability in four regions of the Antarctic Peninsula were investigated using three species of sympatrically breeding Pygoscelis penguins as biomonitors. Eggshells with intact membranes from Adélie, Gentoo, and Chinstrap penguins were collected at 24 breeding colonies in the South Orkney Islands, South Shetland Islands, eastern Antarctic Peninsula, and western Antarctic Peninsula during the 2006/2007 austral summer. In addition, we compared eggshell membrane mercury concentrations with eggshell stable isotope values (δ15N and δ13C) to determine if species-specific trophic or foraging habitat preferences influenced female mercury exposure prior to breeding. With few exceptions, mercury concentrations were found to be fairly homogeneous throughout the Antarctic Peninsula suggesting little spatial variation in the risk of exposure to dietary mercury in this food web. Mercury concentrations in Gentoo and Adélie penguins were similar while Chinstrap penguins tended to have higher eggshell membrane mercury concentrations than their congeners. However, inter and intra-specific differences in eggshell membrane mercury concentration were not related to eggshell δ15N or δ13C values, a likely result of all three species foraging at similar trophic positions. The lack of regional-scale differences in mercury availability in this marine ecosystem may be a reflection of generally uniform atmospheric deposition and upwelling of regionally homogeneous deep water rather than from geographically distinct point sources. -- Highlights: ► We examined regional patterns of mercury availability in the Antarctic Peninsula. ► Three species of Pygoscelis penguins were used as biomonitors. ► Chinstrap penguins tended to have higher mercury than Ad

  1. Penguin eggshell membranes reflect homogeneity of mercury in the marine food web surrounding the Antarctic Peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Brasso, Rebecka L., E-mail: rlb1196@uncw.edu [University of North Carolina Wilmington, Department of Biology and Marine Biology, 601 South College Road, Wilmington, NC 28403 (United States); Polito, Michael J. [University of North Carolina Wilmington, Department of Biology and Marine Biology, 601 South College Road, Wilmington, NC 28403 (United States); Lynch, Heather J. [Ecology and Evolution Department, 640 Life Sciences Bldg., Stony Brook University, Stony Brook, NY 11794 (United States); Naveen, R. [Oceanites Inc., PO Box 15259, Chevy Chase, MD 20825 (United States); Emslie, Steven D. [University of North Carolina Wilmington, Department of Biology and Marine Biology, 601 South College Road, Wilmington, NC 28403 (United States)

    2012-11-15

    Remote regions such as the Antarctic have become increasingly important for investigations into far-reaching anthropogenic impacts on the environment, most recently in regard to the global mercury cycle. Spatial patterns of mercury availability in four regions of the Antarctic Peninsula were investigated using three species of sympatrically breeding Pygoscelis penguins as biomonitors. Eggshells with intact membranes from Adelie, Gentoo, and Chinstrap penguins were collected at 24 breeding colonies in the South Orkney Islands, South Shetland Islands, eastern Antarctic Peninsula, and western Antarctic Peninsula during the 2006/2007 austral summer. In addition, we compared eggshell membrane mercury concentrations with eggshell stable isotope values ({delta}{sup 15}N and {delta}{sup 13}C) to determine if species-specific trophic or foraging habitat preferences influenced female mercury exposure prior to breeding. With few exceptions, mercury concentrations were found to be fairly homogeneous throughout the Antarctic Peninsula suggesting little spatial variation in the risk of exposure to dietary mercury in this food web. Mercury concentrations in Gentoo and Adelie penguins were similar while Chinstrap penguins tended to have higher eggshell membrane mercury concentrations than their congeners. However, inter and intra-specific differences in eggshell membrane mercury concentration were not related to eggshell {delta}{sup 15}N or {delta}{sup 13}C values, a likely result of all three species foraging at similar trophic positions. The lack of regional-scale differences in mercury availability in this marine ecosystem may be a reflection of generally uniform atmospheric deposition and upwelling of regionally homogeneous deep water rather than from geographically distinct point sources. -- Highlights: Black-Right-Pointing-Pointer We examined regional patterns of mercury availability in the Antarctic Peninsula. Black-Right-Pointing-Pointer Three species of Pygoscelis

  2. Cephalopods as vectors of harmful algal bloom toxins in marine food webs.

    Science.gov (United States)

    Lopes, Vanessa M; Lopes, Ana Rita; Costa, Pedro; Rosa, Rui

    2013-09-01

    Here we summarize the current knowledge on the transfer and accumulation of harmful algal bloom (HAB)-related toxins in cephalopods (octopods, cuttlefishes and squids). These mollusks have been reported to accumulate several HAB-toxins, namely domoic acid (DA, and its isomers), saxitoxin (and its derivatives) and palytoxin (and palytoxin-like compounds) and, therefore, act as HAB-toxin vectors in marine food webs. Coastal octopods and cuttlefishes store considerably high levels of DA (amnesic shellfish toxin) in several tissues, but mainly in the digestive gland (DG)--the primary site of digestive absorption and intracellular digestion. Studies on the sub-cellular partitioning of DA in the soluble and insoluble fractions showed that nearly all DA (92.6%) is found in the cytosol. This favors the trophic transfer of the toxins since cytosolic substances can be absorbed by predators with greater efficiency. The available information on the accumulation and tissue distribution of DA in squids (e.g., in stranded Humboldt squids, Dosidicus gigas) is scarcer than in other cephalopod groups. Regarding paralytic shellfish toxins (PSTs), these organisms accumulate them at the greatest extent in DG > kidneys > stomach > branchial hearts > posterior salivary glands > gills. Palytoxins are among the most toxic molecules identified and stranded octopods revealed high contamination levels, with ovatoxin (a palytoxin analogue) reaching 971 μg kg⁻¹ and palytoxin reaching 115 μg kg⁻¹ (the regulatory limit for PlTXs is 30 μg kg⁻¹ in shellfish). Although the impacts of HAB-toxins in cephalopod physiology are not as well understood as in fish species, similar effects are expected since they possess a complex nervous system and highly developed brain comparable to that of the vertebrates. Compared to bivalves, cephalopods represent a lower risk of shellfish poisoning in humans, since they are usually consumed eviscerated, with exception of traditional dishes from the

  3. Global trends in world fisheries: impacts on marine ecosystems and food security.

    Science.gov (United States)

    Pauly, Daniel; Watson, Reg; Alder, Jackie

    2005-01-29

    This contribution, which reviews some broad trends in human history and in the history of fishing, argues that sustainability, however defined, rarely if ever occurred as a result of an explicit policy, but as result of our inability to access a major part of exploited stocks. With the development of industrial fishing, and the resulting invasion of the refuges previously provided by distance and depth, our interactions with fisheries resources have come to resemble the wars of extermination that newly arrived hunters conducted 40,000-50,000 years ago in Australia, and 11,000-13,000 years ago against large terrestrial mammals arrived in North America. These broad trends are documented here through a map of change in fish sizes, which displays characteristic declines, first in the nearshore waters of industrialized countries of the Northern Hemisphere, then spread offshore and to the Southern Hemisphere. This geographical extension met its natural limit in the late 1980s, when the catches from newly accessed stocks ceased to compensate for the collapse in areas accessed earlier, hence leading to a gradual decline of global landing. These trends affect developing countries more than the developed world, which have been able to meet the shortfall by increasing imports from developing countries. These trends, however, together with the rapid growth of farming of carnivorous fishes, which consumes other fishes suited for human consumption, have led to serious food security issues. This promotes urgency to the implementation of the remedies traditionally proposed to alleviate overfishing (reduction of overcapacity, enforcement of conservative total allowable catches, etc.), and to the implementation of non-conventional approaches, notably the re-establishment of the refuges (also known as marine reserves), which made possible the apparent sustainability of pre-industrial fisheries. PMID:15713585

  4. Transfer of radionuclides from high polluted bottom sediments to marine organisms through benthic food chain in post Fukushima period

    Science.gov (United States)

    Bezhenar, Roman; Jung, Kyung Tae; Maderich, Vladimir; Willemsen, Stefan; de With, Govert; Qiao, Fangli

    2015-04-01

    A catastrophic earthquake and tsunami occurred on March 11, 2011 and severely damaged the Fukushima Daiichi Nuclear Power Plant (FDNPP) that resulted in an uncontrolled release of radioactivity into air and ocean. Around 80% of the radioactivity released due to the FDNPP accident in March-April 2011 was either directly discharged into the ocean or deposited onto the ocean surface from the atmosphere. A large amount of long-lived radionuclides (mainly Cs-137) were released into the environment. The concentration of radionuclides in the ocean reached a maximum in mid-April of 2011, and then gradually decreased. From 2011 the concentration of Cs-137 in water essentially fell except the area around the FDNPP where leaks of contaminated water are continued. However, in the bottom sediment high concentrations of Cs-137 were found in the first months after the accident and slowly decreased with time. Therefore, it should be expected that a time delay is found of sediment-bound radionuclides in marine organisms. For the modeling of radionuclide transfer from highly polluted bottom sediments to marine organisms the dynamical food chain model BURN-POSEIDON (Heling et al, 2002; Maderich et al., 2014) was extended. In this model marine organisms are grouped into a limited number of classes based on their trophic level and type of species. These include: phytoplankton, zooplankton, fishes (two types: piscivorous and non-piscivorous), crustaceans, and molluscs for pelagic food chain and bottom sediment invertebrates, demersal fishes and bottom predators for benthic food chain and whole water column predators feeding by pelagial and benthic fishes. Bottom invertebrates consume organic parts of bottom sediments with adsorbed radionuclides which then migrate through the food chain. All organisms take radionuclides directly from water as well as via food. In fishes where radioactivity is not homogeneously distributed over all tissues of the organism, it is assumed that radionuclide

  5. Air quality monitoring in communities of the Canadian Arctic during the high shipping season with a focus on local and marine pollution

    Directory of Open Access Journals (Sweden)

    A. A. Aliabadi

    2015-03-01

    Full Text Available The Canadian Arctic has experienced decreasing sea ice extent and increasing shipping activity in recent decades. While there are economic incentives to develop resources in the north, there are environmental concerns that increasing marine traffic will contribute to declining air quality in northern communities. In an effort to characterize the relative impact of shipping on air quality in the north, two monitoring stations have been installed in Cape Dorset and Resolute, Nunavut, and have been operational since 1 June 2013. The impact of shipping and other sources of emissions on NOx, O3, SO2, BC, and PM2.5 pollution have been characterized for the 2013 shipping season from 1 June to 1 November. In addition, a high-resolution Air Quality Health Index (AQHI for both sites was computed. Shipping consistently increased O3 mixing ratio and PM2.5 concentration. The 90% confidence interval for mean difference in O3 mixing ratio between ship- and no ship-influenced air masses were up to 4.6–4.7 ppb and 2.5–2.7 ppb for Cape Dorset and Resolute, respectively. The same intervals for PM2.5 concentrations were up to 1.8–1.9 μg m−3 and 0.5–0.6 μg m−3. Ship-influenced air masses consistently exhibited an increase of 0.1 to 0.3 in the high-resolution AQHI compared to no ship-influenced air masses. Trajectory cluster analysis in combination with ship traffic tracking provided an estimated range for percent ship contribution to NOx, O3, SO2, and PM2.5 that were 12.9–17.5 %, 16.2–18.1 %, 16.9–18.3 %, and 19.5–31.7 % for Cape Dorset and 1.0–7.2 %, 2.9–4.8 %, 5.5–10.0 %, and 6.5–7.2 % for Resolute during the 2013 shipping season. Additional measurements in Resolute suggested that percent ship contribution to black carbon was 4.3–9.8 % and that black carbon constituted 1.3–9.7 % of total PM2.5 mass in ship plumes. Continued air quality monitoring in the above sites for future shipping seasons will improve the statistics in our

  6. Air quality monitoring in communities of the Canadian Arctic during the high shipping season with a focus on local and marine pollution

    Science.gov (United States)

    Aliabadi, A. A.; Staebler, R. M.; Sharma, S.

    2015-03-01

    The Canadian Arctic has experienced decreasing sea ice extent and increasing shipping activity in recent decades. While there are economic incentives to develop resources in the north, there are environmental concerns that increasing marine traffic will contribute to declining air quality in northern communities. In an effort to characterize the relative impact of shipping on air quality in the north, two monitoring stations have been installed in Cape Dorset and Resolute, Nunavut, and have been operational since 1 June 2013. The impact of shipping and other sources of emissions on NOx, O3, SO2, BC, and PM2.5 pollution have been characterized for the 2013 shipping season from 1 June to 1 November. In addition, a high-resolution Air Quality Health Index (AQHI) for both sites was computed. Shipping consistently increased O3 mixing ratio and PM2.5 concentration. The 90% confidence interval for mean difference in O3 mixing ratio between ship- and no ship-influenced air masses were up to 4.6-4.7 ppb and 2.5-2.7 ppb for Cape Dorset and Resolute, respectively. The same intervals for PM2.5 concentrations were up to 1.8-1.9 μg m-3 and 0.5-0.6 μg m-3. Ship-influenced air masses consistently exhibited an increase of 0.1 to 0.3 in the high-resolution AQHI compared to no ship-influenced air masses. Trajectory cluster analysis in combination with ship traffic tracking provided an estimated range for percent ship contribution to NOx, O3, SO2, and PM2.5 that were 12.9-17.5 %, 16.2-18.1 %, 16.9-18.3 %, and 19.5-31.7 % for Cape Dorset and 1.0-7.2 %, 2.9-4.8 %, 5.5-10.0 %, and 6.5-7.2 % for Resolute during the 2013 shipping season. Additional measurements in Resolute suggested that percent ship contribution to black carbon was 4.3-9.8 % and that black carbon constituted 1.3-9.7 % of total PM2.5 mass in ship plumes. Continued air quality monitoring in the above sites for future shipping seasons will improve the statistics in our analysis and characterize repeating seasonal patterns

  7. Air quality monitoring in communities of the Canadian Arctic during the high shipping season with a focus on local and marine pollution

    Directory of Open Access Journals (Sweden)

    A. A. Aliabadi

    2014-11-01

    Full Text Available The Canadian Arctic has experienced decreasing sea ice extent and increasing shipping activity in the recent decades. While there are economic incentives to develop resources in the North, there are environmental concerns that increasing marine traffic will contribute to declining air quality in Northern communities. In an effort to characterize the relative impact of shipping on air quality in the North, two monitoring stations have been installed in Cape Dorset and Resolute, Nunavut, and have been operational since 1 June 2013. The impact of shipping and other sources of emissions on NOx, O3, SO2, BC, and PM2.5 pollution have been characterized for the 2013 shipping season from 1 June to 1 November. In addition, a high resolution Air Quality Health Index (AQHI for both sites was computed. Shipping consistently increased O3 mixing ratio and PM2.5 concentration. The 90% confidence interval for mean difference in O3 mixing ratio between ship and no ship-influenced air masses were up to 4.6–4.7 ppb and 2.5–2.7 ppb for Cape Dorset and Resolute, respectively. The same intervals for PM2.5 concentrations were up to 1.8–1.9 μg m−3 and 0.5–0.6 μg m−3. Ship-influenced air masses consistently exhibited degraded air quality by an increase of 0.1 to 0.3 in the high resolution AQHI compared to no ship-influenced air masses. Trajectory cluster analysis in combination with ship traffic tracking provided an estimated range for percent ship contribution to NOx, O3, SO2, and PM2.5 that were 12.9–17.5%, 16.2–18.1%, 16.9–18.3%, and 19.5–31.7% for Cape Dorset and 1.0–7.2%, 2.9–4.8%, 5.5–10.0%, and 6.5–7.2% for Resolute during the 2013 shipping season. Additional measurements in Resolute suggested that percent ship contribution to black carbon was 4.3–9.8% and that black carbon constituted 1.3–9.7% of total PM2.5 mass in ship plumes. Continued air quality monitoring in the above sites for future shipping seasons will improve the

  8. Estimating effects of tidal power projects and climate change on threatened and endangered marine species and their food web.

    Science.gov (United States)

    Busch, D Shallin; Greene, Correigh M; Good, Thomas P

    2013-12-01

    Marine hydrokinetic power projects will operate as marine environments change in response to increased atmospheric carbon dioxide concentrations. We considered how tidal power development and stressors resulting from climate change may affect Puget Sound species listed under the U.S. Endangered Species Act (ESA) and their food web. We used risk tables to assess the singular and combined effects of tidal power development and climate change. Tidal power development and climate change posed risks to ESA-listed species, and risk increased with incorporation of the effects of these stressors on predators and prey of ESA-listed species. In contrast, results of a model of strikes on ESA-listed species from turbine blades suggested that few ESA-listed species are likely to be killed by a commercial-scale tidal turbine array. We applied scenarios to a food web model of Puget Sound to explore the effects of tidal power and climate change on ESA-listed species using more quantitative analytical techniques. To simulate development of tidal power, we applied results of the blade strike model. To simulate environmental changes over the next 50 years, we applied scenarios of change in primary production, plankton community structure, dissolved oxygen, ocean acidification, and freshwater flooding events. No effects of tidal power development on ESA-listed species were detected from the food web model output, but the effects of climate change on them and other members of the food web were large. Our analyses exemplify how natural resource managers might assess environmental effects of marine technologies in ways that explicitly incorporate climate change and consider multiple ESA-listed species in the context of their ecological community. Estimación de los Efectos de Proyectos de Energía de las Mareas y el Cambio Climático sobre Especies Marinas Amenazadas y en Peligro y su Red Alimentaria. PMID:24299085

  9. Diversity of Arctic Pelagic Prokaryotes with an emphasis on photoheterotrophic bacteria: a review

    Directory of Open Access Journals (Sweden)

    D. Boeuf

    2014-02-01

    Full Text Available The Arctic Ocean is a unique marine environment with respect to seasonality of light, temperature, perennial ice cover and strong stratification. Other important distinctive features are the influence of extensive continental shelves and its interactions with Atlantic and Pacific water masses and freshwater from sea ice melt and rivers. These characteristics have major influence on the biological and biogeochemical processes occurring in this complex natural system. Heterotrophic bacteria are crucial components of marine food webs and have key roles in controlling carbon fluxes in the oceans. Although it was previously thought that these organisms relied on the organic carbon in seawater for all of their energy needs, several recent discoveries now suggest that pelagic bacteria can depart from a strictly heterotrophic lifestyle by obtaining energy through unconventional mechanisms that are linked to the penetration of sunlight into surface waters. These photoheterotrophic mechanisms may play a significant role in the energy budget in the euphotic zone of marine environments. We can suspect that this role could be of greater importance in the Arctic Ocean where environmental changes triggered by climate change could favor the photoheterotrophic lifestyle. Here we review advances in our knowledge of the diversity of marine photoheterotrophic bacteria and discuss their significance in the Arctic Ocean gained in the framework of the Malina cruise.

  10. Bioaccumulation and trophic transfer of polybrominated diphenyl ethers (PBDEs) in a marine food web from Liaodong Bay, North China

    International Nuclear Information System (INIS)

    Highlights: • BDE-47 was the dominating congener in organisms of the Liaodong Bay. • The length of food chain played an important role on the TMFs. • PBDEs were steadily metabolized in the trophic transfer process along the food chain. -- Abstract: The concentrations of 21 polybrominated diphenyl ethers (PBDEs) congeners were analyzed in organisms within a marine food web collected from the Liaodong Bay, North China. The total concentrations of PBDEs in all samples ranged from 0.87 to 91.4 ng g−1 lipid weight (lw). BDE-47 was the predominant congener and had a concentration ranging from 0.30 to 36.1 ng g−1 lw. The trophic magnification factors (TMF) of the PBDEs were calculated using the trophic levels obtained from the stable nitrogen isotope ratios. The TMF value of ∑PBDEs was 3.50 for the entire food web and 2.21 for the food web excluding seabirds. Four concentration ratios, BDE-99/BDE-100, BDE-99/BDE-47, BDE-153/BDE-154 and BDE-183/BDE-154, decreased linearly with the increase of the trophic levels in the invertebrates and the fishes (p < 0.01). The results suggested that the PBDEs were steadily metabolized in the trophic transfer process along the food chain

  11. Accumulation of organochlorines and brominated flame retardants in estuarine and marine food chains: field measurements and model calculations.

    Science.gov (United States)

    Veltman, Karin; Hendriks, Jan; Huijbregts, Mark; Leonards, Pim; van den Heuvel-Greve, Martine; Vethaak, Dick

    2005-10-01

    Food chain accumulation of organochlorines and brominated flame retardants in estuarine and marine environments is compared to model estimations and fresh water field data. The food chain consists of herbivores, detritivores and primary and secondary carnivores i.e. fish, fish-eating birds and marine mammals. Accumulation of polychlorinated biphenyls is predicted well by OMEGA for herbi-detritivores and primary and secondary carnivorous fish. Ratios are similar to those found for fresh water species. Accumulation ratios for fish-eating birds and mammals are overestimated by the model, which is attributed partly to biotransformation of meta-para unsubstituted congeners. Additionally, birds may feed in other less polluted areas. For brominated diphenylethers (BDE) accumulation patterns are highly species and congener specific. Accumulation depends on both K(ow) and metabolization capacities. BDE47 is the predominant congener in lower trophic levels. For marine birds and mammals accumulation ratios of BDE99 and 100 are similar to or higher than ratios of persistent PCBs. PMID:15893330

  12. State of the Arctic Environment

    International Nuclear Information System (INIS)

    The Arctic environment, covering about 21 million km2, is in this connection regarded as the area north of the Arctic Circle. General biological and physical features of the terrestrial and freshwater environments of the Arctic are briefly described, but most effort is put into a description of the marine part which constitutes about two-thirds of the total Arctic environment. General oceanography and morphological characteristics are included; e.g. that the continental shelf surrounding the Arctic deep water basins covers approximately 36% of the surface areas of Arctic waters, but contains only 2% of the total water masses. Blowout accident may release thousands of tons of oil per day and last for months. They occur statistically very seldom, but the magnitude underlines the necessity of an efficient oil spill contingency as well as sound safety and quality assurance procedures. Contingency plans should be coordinated and regularly evaluated through simulated and practical tests of performance. Arctic conditions demand alternative measures compared to those otherwise used for oil spill prevention and clean-up. New concepts or optimization of existing mechanical equipment is necessary. Chemical and thermal methods should be evaluated for efficiency and possible environmental effects. Both due to regular discharges of oil contaminated drilled cuttings and the possibility of a blowout or other spills, drilling operations in biological sensitive areas may be regulated to take place only during the less sensitive parts of the year. 122 refs., 8 figs., 8 tabs

  13. An environmental tax towards more sustainable food consumption: empirical evidence of the French meat and marine food consumption

    OpenAIRE

    Bonnet, Céline; Bouamra-Mechemache, Zohra; Corre, Tifenn

    2016-01-01

    After fossil fuels, agricultural production and fisheries are industries with the largest impact on the environment in terms of greenhouse gas (GHG) emissions, especially in the production of ruminant meats such as beef, veal or lamb. In order to reduce this environmental impact, consumers can change their food consumption habits to utilize less polluting products such as white meats or vegetable food products. We analyze whether or not a CO2 equivalent (CO2-eq) tax policy can change consumer...

  14. Using marine reserves to manage impact of bottom trawl fisheries requires consideration of benthic food-web interactions

    DEFF Research Database (Denmark)

    van Denderen, Pieter Daniël; Rijnsdorp, Adriaan D.; van Kooten, Tobias

    2016-01-01

    Marine protected areas (MPAs) are widely used to protect exploited fish species as well as to conserve marine habitats and their biodiversity. They have become a popular management tool also for bottom trawl fisheries, a common fishing technique on continental shelves worldwide. The effects......-effects of the fishery. However, predicting the protective effects of MPAs is complicated because the side-effects of trawling potentially alter the food-web interactions between target and non-target species. These changes in predatory and competitive interactions among fish and benthic invertebrates may have important...... ramifications for MPAs as tools to manage or mitigate the effects of bottom trawling. Yet, in current theory regarding the functioning of MPAs in relation to bottom trawl fisheries, such predatory and competitive interactions between species are generally not taken into account. In this paper, we discuss how...

  15. The metabolic response of marine copepods to environmental warming and ocean acidification in the absence of food

    Science.gov (United States)

    Mayor, Daniel J.; Sommer, Ulf; Cook, Kathryn B.; Viant, Mark R.

    2015-09-01

    Marine copepods are central to the productivity and biogeochemistry of marine ecosystems. Nevertheless, the direct and indirect effects of climate change on their metabolic functioning remain poorly understood. Here, we use metabolomics, the unbiased study of multiple low molecular weight organic metabolites, to examine how the physiology of Calanus spp. is affected by end-of-century global warming and ocean acidification scenarios. We report that the physiological stresses associated with incubation without food over a 5-day period greatly exceed those caused directly by seawater temperature or pH perturbations. This highlights the need to contextualise the results of climate change experiments by comparison to other, naturally occurring stressors such as food deprivation, which is being exacerbated by global warming. Protein and lipid metabolism were up-regulated in the food-deprived animals, with a novel class of taurine-containing lipids and the essential polyunsaturated fatty acids (PUFAs), eicosapentaenoic acid and docosahexaenoic acid, changing significantly over the duration of our experiment. Copepods derive these PUFAs by ingesting diatoms and flagellated microplankton respectively. Climate-driven changes in the productivity, phenology and composition of microplankton communities, and hence the availability of these fatty acids, therefore have the potential to influence the ability of copepods to survive starvation and other environmental stressors.

  16. Arctic methane

    NARCIS (Netherlands)

    Dyupina, E.; Amstel, van A.R.

    2013-01-01

    What are the risks of a runaway greenhouse effect from methane release from hydrates in the Arctic? In January 2013, a dramatic increase of methane concentration up to 2000 ppb has been measured over the Arctic north of Norway in the Barents Sea. The global average being 1750 ppb. It has been sugges

  17. Arctic Newcomers

    DEFF Research Database (Denmark)

    Tonami, Aki

    2013-01-01

    Interest in the Arctic region and its economic potential in Japan, South Korea and Singapore was slow to develop but is now rapidly growing. All three countries have in recent years accelerated their engagement with Arctic states, laying the institutional frameworks needed to better understand an...

  18. Climate Change, Globalization and Geopolitics in the New Maritime Arctic

    Science.gov (United States)

    Brigham, L. W.

    2011-12-01

    Early in the 21st century a confluence of climate change, globalization and geopolitics is shaping the future of the maritime Arctic. This nexus is also fostering greater linkage of the Arctic to the rest of the planet. Arctic sea ice is undergoing a historic transformation of thinning, extent reduction in all seasons, and reduction in the area of multiyear ice in the central Arctic Ocean. Global Climate Model simulations of Arctic sea ice indicate multiyear ice could disappear by 2030 for a short period of time each summer. These physical changes invite greater marine access, longer seasons of navigation, and potential, summer trans-Arctic voyages. As a result, enhanced marine safety, environmental protection, and maritime security measures are under development. Coupled with climate change as a key driver of regional change is the current and future integration of the Arctic's natural wealth with global markets (oil, gas and hard minerals). Abundant freshwater in the Arctic could also be a future commodity of value. Recent events such as drilling for hydrocarbons off Greenland's west coast and the summer marine transport of natural resources from the Russian Arctic to China across the top of Eurasia are indicators of greater global economic ties to the Arctic. Plausible Arctic futures indicate continued integration with global issues and increased complexity of a range of regional economic, security and environmental challenges.

  19. Potential for mercury reduction by microbes in the high arctic.

    Science.gov (United States)

    Poulain, Alexandre J; Ní Chadhain, Sinéad M; Ariya, Parisa A; Amyot, Marc; Garcia, Edenise; Campbell, Peter G C; Zylstra, Gerben J; Barkay, Tamar

    2007-04-01

    The contamination of polar regions due to the global distribution of anthropogenic pollutants is of great concern because it leads to the bioaccumulation of toxic substances, methylmercury among them, in Arctic food chains. Here we present the first evidence that microbes in the high Arctic possess and express diverse merA genes, which specify the reduction of ionic mercury [Hg(II)] to the volatile elemental form [Hg(0)]. The sampled microbial biomass, collected from microbial mats in a coastal lagoon and from the surface of marine macroalgae, was comprised of bacteria that were most closely related to psychrophiles that had previously been described in polar environments. We used a kinetic redox model, taking into consideration photoredox reactions as well as mer-mediated reduction, to assess if the potential for Hg(II) reduction by Arctic microbes can affect the toxicity and environmental mobility of mercury in the high Arctic. Results suggested that mer-mediated Hg(II) reduction could account for most of the Hg(0) that is produced in high Arctic waters. At the surface, with only 5% metabolically active cells, up to 68% of the mercury pool was resolved by the model as biogenic Hg(0). At a greater depth, because of incident light attenuation, the significance of photoredox transformations declined and merA-mediated activity could account for up to 90% of Hg(0) production. These findings highlight the importance of microbial redox transformations in the biogeochemical cycling, and thus the toxicity and mobility, of mercury in polar regions.

  20. Signal and distribution of volatile Mercury (Hg0) in the Marine High Arctic During Polar Summer in the Sequel of Enhanced Atmospheric Deposition of HgⅡ

    Institute of Scientific and Technical Information of China (English)

    Jonas O. Sommar; Maria E. Andersson

    2008-01-01

    @@ 1 Introduction It has been elucidated that high levels of neurotoxic mercury (Hg) in the Arctic is related to a rapid, near-compete depletion of Hg0 (MDE) in the atmospheric boundary-layer occurring episodically during the Polar spring[1].

  1. CEEPRA - Collaboration Network on EuroArctic Environmental Radiation Protection and Research

    International Nuclear Information System (INIS)

    CEEPRA (Collaboration Network on EuroArctic Environmental Radiation Protection and Research) is an EU-funded project acting under the Kolarctic ENPI CBC programme. The CEEPRA project's main aim is to develop a collaboration network between key radiation research institutions in the EuroArctic region, which will lead to improved emergency preparedness capabilities in the event of any nuclear accidents. The project is studying the current state of radioactive contamination in the terrestrial and marine ecosystems in the EuroArctic region by examining environmental samples collected from Lapland in Finland, Finnmark and Troms in Norway, the Kola Peninsula in Russia and in the Barents Sea. The results provide updated information on the present levels, occurrence and the fate of radioactive substances in the Arctic environments and food chains. Special attention is given to collection and analyses of natural products widely used by general public in Finland, Russia and Norway, such as berries, mushrooms, fish and reindeer meat. The region-specific risk assessments are carried out through modelling and studying of long-term effects of potential nuclear accidents in the EuroArctic region and possible impacts on the region's indigenous population, terrestrial and marine environments, reindeer husbandry, the natural product sector, tourism and industries. The project partners are Radiation and Nuclear Safety Authority (STUK) from Finland, the Murmansk Marine Biological Institute (MMBI) from Russia, the Norwegian Radiation Protection Authority (NRPA), Finnish Meteorological Institute and Poeyry Finland Oy. The Southern Scientific Centre of the Russian Academy of Sciences (SSC RAS) and Norwegian Meteorological Institute (MET) are taking part in the project as well. The main results of the project are presented in this study. Document available in abstract form only. (authors)

  2. CEEPRA - Collaboration Network on EuroArctic Environmental Radiation Protection and Research

    Energy Technology Data Exchange (ETDEWEB)

    Solatie, D.; Leppaenen, A.P. [STUK-Radiation and Nuclear Safety Authority (Finland); Kasatkina, N. [Murmansk Marine Biological Institute (Russian Federation); Nalbandyan, A. [Norwegian Radiation Protection Authority (Norway); Paatero, J. [Finnish Meteorological Institute (Finland); Reinikainen, K.; Nissi, M. [Poeyry Finland Oy (Finland); Vaaramaa, K. [Radiation and Nuclear Safety Authority (Finland)

    2014-07-01

    CEEPRA (Collaboration Network on EuroArctic Environmental Radiation Protection and Research) is an EU-funded project acting under the Kolarctic ENPI CBC programme. The CEEPRA project's main aim is to develop a collaboration network between key radiation research institutions in the EuroArctic region, which will lead to improved emergency preparedness capabilities in the event of any nuclear accidents. The project is studying the current state of radioactive contamination in the terrestrial and marine ecosystems in the EuroArctic region by examining environmental samples collected from Lapland in Finland, Finnmark and Troms in Norway, the Kola Peninsula in Russia and in the Barents Sea. The results provide updated information on the present levels, occurrence and the fate of radioactive substances in the Arctic environments and food chains. Special attention is given to collection and analyses of natural products widely used by general public in Finland, Russia and Norway, such as berries, mushrooms, fish and reindeer meat. The region-specific risk assessments are carried out through modelling and studying of long-term effects of potential nuclear accidents in the EuroArctic region and possible impacts on the region's indigenous population, terrestrial and marine environments, reindeer husbandry, the natural product sector, tourism and industries. The project partners are Radiation and Nuclear Safety Authority (STUK) from Finland, the Murmansk Marine Biological Institute (MMBI) from Russia, the Norwegian Radiation Protection Authority (NRPA), Finnish Meteorological Institute and Poeyry Finland Oy. The Southern Scientific Centre of the Russian Academy of Sciences (SSC RAS) and Norwegian Meteorological Institute (MET) are taking part in the project as well. The main results of the project are presented in this study. Document available in abstract form only. (authors)

  3. Anadromous char as an alternate food choice to marine animals: A synthesis of Hg concentrations, population features and other influencing factors

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Marlene S., E-mail: marlene.evans@ec.gc.ca [Environment Canada, Water Science and Technology Directorate, 11 Innovation Blvd., Saskatoon SK S7N 3H5 (Canada); Muir, Derek C.G. [Environment Canada, Water Science and Technology Directorate, 867 Lakeshore Rd., Burlington, ON L7R 4A6 (Canada); Keating, Jonathan [Environment Canada, Water Science and Technology Directorate, 11 Innovation Blvd., Saskatoon SK S7N 3H5 (Canada); Wang, Xiaowa [Environment Canada, Water Science and Technology Directorate, 867 Lakeshore Rd., Burlington, ON L7R 4A6 (Canada)

    2015-03-15

    and marine vertebrates in traditional diets. The known information on anadromous char is reviewed including population features, habitat, and harvests. Future Hg trend monitoring should focus on specific locations and harvest areas within these areas to better assess trends and influencing factors. - Highlights: • Mercury concentrations were very low (0.05 ± 0.02 µg/g) in anadromous char across northern Canada. • Hg concentrations increased with fish size, decreasing condition factor and cooler springs. • Hg concentrations seemed to increase on the long-term but decrease in recent times. • Char are a good food choice for those who want to maintain traditional diets while reducing Hg intake. • Anadromous char often are habitat-limited and most abundant in large lakes with ready sea access.

  4. Anadromous char as an alternate food choice to marine animals: A synthesis of Hg concentrations, population features and other influencing factors

    International Nuclear Information System (INIS)

    This study was conducted to confirm sporadic measurements made over the late 1970s to the early 1990s which determined that mercury (Hg) concentrations were low in anadromous char across Arctic and subarctic Canada including northern Québec and Labrador. Over 2004–2013, anadromous char populations across northern Canada were investigated at 20 sites for Hg concentrations and life history characteristics. Hg concentrations were extremely low in anadromous char muscle, typically < 0.05 μg/g (wet weight) and, at each location, generally increased with fish length, age and nitrogen isotope (δ15N) ratio and decreased with condition factor and %lipid; correlations with carbon isotope (δ13C) ratio were inconsistent. Location and year were significant variables influencing Hg concentrations over the study area; longitude and latitude also were significant influencing variables. Char length, weight, age, condition factor and lipid content explained additional variance. A tendency towards higher Hg concentrations with increasing latitude may be partially related to decreasing growth of char towards the north. However, Hg concentrations in char were positively correlated with growth rates suggesting that Hg concentrations in char also were higher in the more productive study areas, including to the west where mainland riverine inputs of terrestrial carbon, nutrients, and Hg were greater. The data base for assessing time trends in char was limited by the small number of years investigated at most locations, variable fish size across years, small sample size, etc. Where temporal trends were detected, they were of increase on the long term (1970s, 1980s or early 1990s to the present) but of decrease on the short term (early 2000s to present) with Nain (Labrador) showing the converse pattern. Higher Hg concentrations were also related to lower condition factor and cooler springs. Hg concentrations in anadromous char are compared with other terrestrial, aquatic and marine

  5. Infochemicals structure marine, terrestrial and freshwater food webs: Implications for ecological informatics

    NARCIS (Netherlands)

    Vos, M.; Vet, L.E.M.; Wackers, F.L.; Middelburg, J.J.; Putten, van der W.H.; Mooij, W.M.; Heip, C.H.R.; Donk, van E.

    2006-01-01

    Here we consider how information transfer shapes interactions in aquatic and terrestrial food webs. All organisms, whether they are dead or alive, release certain chemicals into their environment. These can be used as infochemicals by any other individual in the food web that has the biological mach

  6. Lipids and stable isotopes in marine food webs in West Greenland

    DEFF Research Database (Denmark)

    Møller, Per

    Lipider er essentielle for alle livsformer og er den vigtigste molekyle i energitransporten i de arktiske fødekæder. Inden for det marine miljø har lipidsammensætningen tilpassets, for at maksimere produktiviteten og assimilationseffektiviteten hos primær producenter og konsumenter, med en følgel...

  7. The impact of temperature change on the activity and community composition of sulfate-reducing bacteria in arctic versus temperate marine sediments

    DEFF Research Database (Denmark)

    Robador, Alberto; Brüchert, Volker; Jørgensen, Bo Barker

    2009-01-01

    composition of sulfate-reducing bacteria were studied in the permanently cold sediment of north-western Svalbard (Arctic Ocean) and compared with a temperate habitat with seasonally varying temperature (German Bight, North Sea). Short-term 35S-sulfate tracer incubations in a temperature-gradient block...... (between -3.5°C and +40°C) were used to assess variations in sulfate reduction rates during the course of the experiment. Warming of arctic sediment resulted in a gradual increase of the temperature optima (Topt) for sulfate reduction suggesting a positive selection of psychrotolerant/mesophilic sulfate-reducing...... bacteria (SRB). However, high rates at in situ temperatures compared with maximum rates showed the predominance of psychrophilic SRB even at high incubation temperatures. Changing apparent activation energies (Ea) showed that increasing temperatures had an initial negative impact on sulfate reduction...

  8. Marine and terrestrial foods as a source of brain-selective nutrients for early modern humans in the southwestern Cape, South Africa.

    Science.gov (United States)

    Kyriacou, K; Blackhurst, D M; Parkington, J E; Marais, A D

    2016-08-01

    Many attempts have been made to define and reconstruct the most plausible ecological and dietary niche of the earliest members of the human species. While earlier models emphasise big-game hunting in terrestrial, largely savannah environments, more recent scenarios consider the role of marine and aquatic foods as a source of polyunsaturated fatty acids (PUFA) and other brain-selective nutrients. Along the coast of southern Africa, there appears to be an association between the emergence of anatomically modern humans and accumulation of some of the earliest shell middens during the Middle Stone Age (200-40 ka). Fragmentary fossil remains classified as those of anatomically modern humans, along with marine food residues and numerous material cultural indicators of increased social and behavioural complexity have been recovered from coastal sites. In this paper, new information on the nutrient content of marine and terrestrial foods available to early modern humans in the southwestern Cape is presented and compared with existing data on the nutritional value of some wild plant and animal foods in Africa. The results suggest that coastal foraging, particularly the collection of abundant and predictable marine molluscs, would have allowed early modern humans to exploit some of the richest and most accessible sources of protein, micronutrients and longer-chain omega-6 and omega-3 fatty acids. Reliable and accessible sources of omega-3 eicosapentaenoic and docosahexaenoic acid are considerably more restricted in terrestrial foods. PMID:27457547

  9. Compartments in a marine food web associated with phylogeny, body mass, and habitat structure

    OpenAIRE

    Rezende, Enrico L.; Eva M. Albert; Fortuna, Miguel A.; Bascompte, Jordi

    2009-01-01

    A long-standing question in community ecology is whether food webs are organized in compartments, where species within the same compartment interact frequently among themselves, but show fewer interactions with species from other compartments. Finding evidence for this community organization is important since compartmentalization may strongly affect food web robustness to perturbation. However, few studies have found unequivocal evidence of compartments, and none has quantifie...

  10. Causes and consequences of marine mammal population declines in southwest Alaska: a food-web perspective

    OpenAIRE

    Estes, J. A.; Doak, D F; Springer, A. M.; T. M. Williams

    2009-01-01

    Populations of sea otters, seals and sea lions have collapsed across much of southwest Alaska over the past several decades. The sea otter decline set off a trophic cascade in which the coastal marine ecosystem underwent a phase shift from kelp forests to deforested sea urchin barrens. This interaction in turn affected the distribution, abundance and productivity of numerous other species. Ecological consequences of the pinniped declines are largely unknown. Increased predation by transient (...

  11. Isotopes in the Arctic atmospheric water cycle

    OpenAIRE

    Bonne, Jean-Louis; Werner, Martin; Meyer, Hanno; Kipfstuhl, Sepp; Rabe, Benjamin; Behrens, Melanie; Schönicke, Lutz; Steen-Larsen, Hans Christian; Masson-Delmotte, Valérie

    2016-01-01

    The ISO-ARC project aims at documenting the Arctic atmospheric hydrological cycle, by assessing the imprint of the marine boundary conditions (e.g. temperature variations, circulation changes, or meltwater input) to the isotopic composition of the atmospheric water cycle (H218O and HDO) with a focus on North Atlantic and Arctic oceans. For this purpose, two continuous monitoring water vapour stable isotopes cavity ring-down spectrometers have been installed in July 2015: on-boar...

  12. Resource utilisation by deep-sea megabenthos in the Canadian High Arctic (Baffin Bay and Parry Channel)

    Science.gov (United States)

    Bourgeois, Solveig; Witte, Ursula; Harrison, Ailish M.; Makela, Anni; Kazanidis, Georgios; Archambault, Philippe

    2016-04-01

    Ongoing climate change in the Arctic is causing drastic alteration of the Arctic marine ecosystem functioning, such as shifts in patterns of primary production, and modifying the present tight pelagic-benthic coupling. Subsequently benthic communities, which rely upon organic matter produced in the top layers of the Ocean, will also be affected by these changes. The benthic megafaunal communities play a significant role in ecological processes and ecosystem functioning (i.e. organic matter recycling, bioturbation, food source for the higher trophic levels…). Yet, information is scarce regarding the main food sources for dominant benthic organisms, and therefore the impact of the ongoing changes is difficult to assess. The goal of this study is to investigate the preferential feeding of different carbon sources by megabenthic organisms in the Canadian High Arctic and to identify environmental drivers which explain the observed trends. In summer 2013, benthic megafauna was collected at 9 stations spread along latitudinal (58 to 81°N) and longitudinal (62 to 114°W) transects in the Baffin Bay and Parry Channel, respectively. Carbon and nitrogen bulk stable isotope analyses (δ13C and δ15N) were performed on several species divided into groups according to their feeding type. This study highlights distinct trends in δ13C values of benthic organisms suggesting the importance of both phytoplankton and ice algae as carbon sources for megafauna in the Canadian High Arctic. The importance of physical and biological parameters as drivers of food web structure will be furthermore discussed.

  13. A multitrophic model to quantify the effects of marine viruses on microbial food webs and ecosystem processes

    DEFF Research Database (Denmark)

    Weitz, Joshua S.; Stock, Charles A.; Wilhelm, Steven W.;

    2015-01-01

    of a virus component promotes the emergence of complex communities. In addition, biomass partitioning of the emergent multitrophic community is consistent with well-established empirical norms in the surface oceans. At steady state, ecosystem fluxes can be probed to characterize the effects that viruses have...... that viruses can have significant stimulatory effects across whole-ecosystem scales. We suggest that existing efforts to predict carbon and nutrient cycling without considering virus effects are likely to miss essential features of marine food webs that regulate global biogeochemical cycles.The ISME Journal...... ecosystem models to include a virus component, specifically parameterized for processes taking place in the ocean euphotic zone. Crucially, we are able to solve this model analytically, facilitating evaluation of model behavior under many alternative parameterizations. Analyses reveal that the addition...

  14. Development of a fast DNA extraction method for sea food and marine species identification.

    Science.gov (United States)

    Tagliavia, Marcello; Nicosia, Aldo; Salamone, Monica; Biondo, Girolama; Bennici, Carmelo Daniele; Mazzola, Salvatore; Cuttitta, Angela

    2016-07-15

    The authentication of food components is one of the key issues in food safety. Similarly taxonomy, population and conservation genetics as well as food web structure analysis, also rely on genetic analyses including the DNA barcoding technology. In this scenario we developed a fast DNA extraction method without any purification step from fresh and processed seafood, suitable for any PCR analysis. The protocol allows the fast DNA amplification from any sample, including fresh, stored and processed seafood and from any waste of industrial fish processing, independently of the sample storage method. Therefore, this procedure is particularly suitable for the fast processing of samples and to carry out investigations for the authentication of seafood by means of DNA analysis. PMID:26948627

  15. Arctic bioremediation

    International Nuclear Information System (INIS)

    Cleanup of oil and diesel spills on gravel pads in the Arctic has typically been accomplished by utilizing a water flushing technique to remove the gross contamination or excavating the spill area and placing the material into a lined pit, or a combination of both. Enhancing the biological degradation of hydrocarbon (bioremediation) by adding nutrients to the spill area has been demonstrated to be an effective cleanup tool in more temperate locations. However, this technique has never been considered for restoration in the Arctic because the process of microbial degradation of hydrocarbon in this area is very slow. The short growing season and apparent lack of nutrients in the gravel pads were thought to be detrimental to using bioremediation to cleanup Arctic oil spills. This paper discusses the potential to utilize bioremediation as an effective method to clean up hydrocarbon spills in the northern latitudes

  16. Summer Arctic sea fog

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Synchronous or quasi-synchronous sea-land-air observations were conducted using advanced sea ice, atmospheric and marine instruments during China' s First Arctic Expedition. Based on the Precious data from the expedition, it was found that in the Arctic Ocean, most part of which is covered with ice or is mixed with ice, various kinds of sea fog formed such as advection fog, radiation fog and vapor fog. Each kind has its own characteristic and mechanics of creation. In the southern part of the Arctic Ocean, due to the sufficient warm and wet flow there, it is favorable for advection fog to form,which is dense and lasts a long time. On ice cap or vast floating ice, due to the strong radiation cooling effect, stable radiating fog is likely to form. In floating ice area there forms vapor fog with the appearance of masses of vapor from a boiling pot, which is different from short-lasting land fog. The study indicates that the reason why there are many kinds of sea fog form in the Arctic Ocean is because of the complicated cushion and the consequent sea-air interaction caused by the sea ice distribution and its unique physical characteristics. Sea fog is the atmospheric phenomenon of sea-air heat exchange. Especially, due to the high albedo of ice and snow surface, it is diffcult to absorb great amount of solar radiation during the polar days. Besides, ice is a poor conductor of heat; it blocks the sea-air heat exchange.The sea-air exchange is active in floating ice area where the ice is broken. The sea sends heat to the atmosphere in form of latent heat; vapor fog is a way of sea-air heat exchange influencing the climate and an indicator of the extent of the exchange. The study also indicates that the sea also transports heat to the atmosphere in form of sensible heat when vapor fog occurs.

  17. Arctic bioremediation

    International Nuclear Information System (INIS)

    Cleanup of oil and diesel spills on gravel pads in the Arctic has typically been accomplished by utilizing a water flushing technique to remove the gross contamination or excavating the spill area and placing the material into a lined pit, or a combination of both. This paper discusses the potential to utilize bioremediation as an effective method to clean up hydrocarbon spills in the northern latitudes. Discussed are the results of a laboratory bioremediation study which simulated microbial degradation of hydrocarbon under arctic conditions

  18. Estuarine consumers utilize marine, estuarine and terrestrial organic matter and provide connectivity among these food webs

    Science.gov (United States)

    The flux of organic matter (OM) across ecosystem boundaries can influence estuarine food web dynamics and productivity. However, this process is seldom investigated taking into account all the adjacent ecosystems (e.g. ocean, river, land) and different hydrological settings (i.e....

  19. Influence of dispersants on petroleum bioavailability in a marine food chain

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, M.F.; Younghans-Haug, C.O.; Tjeerdema, R.S. [Univ. of California, Santa Cruz, CA (United States); Sowby, M.L. [Office of Oil Spill Prevention and Response, Sacramento, CA (United States)

    1994-12-31

    Oil spills represent a serious threat to marine organisms. Crude oil consists of numerous compounds with a wide range of physicochemical properties critical in determining those organisms at greatest risk. Surface inhabitants may benefit from the application of dispersing agents, yet little is understood of the disposition of the dispersed components of a spill. As the functional water solubility of petroleum hydrocarbons increases in the water column, the portion that is available for uptake may also increase, placing another group of organisms at risk. Potential increases in adsorption and bioaccumulation may extend the threat of oil spills from marine organisms to human consumers. Studies to date have focused on the acute toxicity of oil and dispersants. The objective of this research was to determine the influence of a dispersant on the bioavailability of crude oil components at concentrations below the no observable effect level (NOEL). Flow-through chambers were used to expose the algae, Isochrysis galbana, to ``undispersed`` Prudhoe Bay Crude Oil (PBCO) spiked with {sup 14}C naphthalene and ``dispersed`` spiked PBCO/Corexit 9527 sea water preparations. Bioavailability to Isochrysis was assessed as uptake, bioconcentration, and deputation of {sup 14}C naphthalene and its metabolites. Results of exposure studies will be presented.

  20. In Situ burning of Arctic marine oil spills:Ignitability of various oil types weathered at different ice conditions. A combined laboratory and field study

    OpenAIRE

    Fritt-Rasmussen, Janne

    2010-01-01

    Oil spills in ice filled and Arctic waters pose other challenges for oil spill response compared to open and temperate waters. In situ burning has been proven to be an effective oil spill response method for oil spills in ice filled waters. This thesis presents results from laboratory and field experiments where the ignitability of oil spill as a function of oil type and weathering conditions (time/ice) was tested. The results show that the composition of the oil and the ice cover is importan...

  1. Stable isotope evidence of terrestrial organic matter incorporation into coastal marine food webs: impact of Rhone River inputs on five NW Mediterranean marine flatfish species.

    Science.gov (United States)

    Darnaude, A. M.; Salen-Picard, C.; Harmelin-Vivien, M.

    2003-04-01

    The positive influence of land-based run-off on coastal fishery production is thought to be of particular importance for oligotrophic seas such as the Mediterranean. In order to estimate the impact of the Rhone River inputs of particulate organic matter (POM) on exploited demersal fish populations, stable isotope signature in nitrogen (δ15N) and carbon (δ13C) were determined for both juveniles and adults of the five main flatfish species living off the Rhone delta (Arnoglossus laterna, Buglossidium luteum, Citharus linguatula, Solea impar and Solea solea) and the main components of their food webs. The five flatfish species showed inter and intra-specific differences in isotopic signatures. The δ15N significantly increased from the smallest species to the largest ones and, in all species, from juveniles to adults (Ptrophic level with fish body size. Concerning the carbon signature, the δ13C obtained indicated an incorporation of organic material from terrestrial origin in the flesh of all the species. This incorporation was minimum for C. linguatula and reduced for all the species with the exception of S. solea for which a significantly (Pstable isotope data were compared with gut content analyses (prey % total contents mass, W%) performed on the same fishes. The δ13C signature of fishes was inversely related to the W% of polychaetes in their diet, and not to other prey categories. The common sole S. solea, that fed mainly on polychaetes (W% > 50% at all benthic stages of life), exhibited the most negative mean δ13C for both juveniles and adults among all the fish species studied. The isotopic analyses of the Rhone River water, the marine phytoplankton, the sediment and the main fish prey, confirmed that polychaetes represented the major pathway of terrestrial POM transfer up to fishes into coastal trophic webs. The effect of terrestrial inputs in enhancing the population dynamics of the five flatfish species studied differed thus according to their diet

  2. Ecology of conflict: marine food supply affects human-wildlife interactions on land

    OpenAIRE

    Artelle, Kyle A.; Anderson, Sean C.; John D. Reynolds; Andrew B Cooper; Paquet, Paul C.; Darimont, Chris T.

    2016-01-01

    Human-wildlife conflicts impose considerable costs to people and wildlife worldwide. Most research focuses on proximate causes, offering limited generalizable understanding of ultimate drivers. We tested three competing hypotheses (problem individuals, regional population saturation, limited food supply) that relate to underlying processes of human-grizzly bear (Ursus arctos horribilis) conflict, using data from British Columbia, Canada, between 1960–2014. We found most support for the limite...

  3. Committee on Natural Toxins and Food Allergens. Marine and freshwater toxins.

    Science.gov (United States)

    Hungerford, James M

    2005-01-01

    There have been major developments this past year in the Marine and Freshwater Toxins topic area (formerly Phycotoxins). These include AOAC approval and inauguration of a new AOAC Presidential Task Force on Marine and Freshwater Toxins to accelerate methods validation, and the appointment of several new Topic Advisors. A joint FAO/IOC/WHO group addressing biotoxins in molluscan bivalves is also relevant to this report and to the new Task Force. The AOAC Presidential Task Force on Marine and Freshwater Toxins is an international group that, in late November 2004, consisted of 90 world experts and stakeholders. Chaired by this General Referee, the group establishes methods priorities based on analytical methods criteria, determines fitness for purpose, identifies and reviews available methodologies, recommends methodologies for validation, and identifies complementary analytical tools. Once appropriate analytical methodology has been identified or developed, the Task Force is able to identify financial and technical resources necessary to validate the methods. The first two formal meetings of the Task Force were held in Bethesda, MD, on May 19, 2004 and in St. Louis, MO, on September 22, 2004. These meetings were held in conjunction with the XI International IUPAC Symposium on Mycotoxins and Phycotoxins and the 118th AOAC INTERNATIONAL Annual Meeting and Exposition, respectively. The Bethesda meeting served to introduce members of the group to the AOAC Community/Task Force model and to discuss objectives, concerns, general workings, and communications. The meeting concluded on an encouraging note, with a commitment from AOAC to help provide financial resources for the review of nonproprietary methods deemed high priority by the Task Force. This development was seen as an important step toward reaching methods validation objectives. The terms of reference for the Task Force were approved by the AOAC Board of Directors in late June, 2004. They described the Task Force

  4. Preservation of Fish by Irradiation. Proceedings of a Panel on the Irradiation Preservation of Foods of Marine Origin

    International Nuclear Information System (INIS)

    The increasing emphasis on the need for protein-rich foods to improve the nutritional status of the world’s population has stimulated research on new methods of preserving fishery products. The sea offers a source of protein that could markedly reduce the protein gap existing in many parts of the world. The major problem in attaining a more complete exploitation of these products is how to preserve them so that they can be transported from the points of origin to areas of greatest need. The use of ionizing radiation as a preservation method has been satisfactorily demonstrated in many countries. In some respects it offers advantages over conventional methods; for example, it prolongs the market life without using heat or chemicals, and what is more, the products are treated while they are sealed in commercial types of containers. Although radiation processing appears feasible, additional research is needed to improve certain quality attributes of some treated foods and to demonstrate to the satisfaction of health authorities' that no deleterious effects result. To obtain advice on the problems that need attention a Panel on Irradiation Preservation of Foods of Marine Origin was convened in Vienna, by the Joint FAO/IAEA Division of Atomic Energy in Food and Agriculture, on 15—19 December 1969. The main purpose of the panel’s work was to advise the Director General of the Food and Agriculture Organization of the United Nations and the Director General of the International Atomic Energy Agency on how these organizations can best fulfil their roles in radiation research on fishery products. The meeting was attended by thirteen experts from various countries and one representative of the World Health Organization. Reports were presented on research performed and detailed discussions were held on work done in perfecting the radurization treatment of fishery products. Evaluations were made of the microbiology of the radurization process, with special reference to

  5. Antimicrobial natural products from Arctic and sub-Arcticmarine invertebrates

    OpenAIRE

    Tadesse, Margey

    2010-01-01

    Infectious diseases are a leading cause of death world-wide and there is a growing need for new anti-infective agents to combat multi-resistant strains of bacteria and fungi. Marine natural products are promising sources of novel antimicrobial compounds. In the present thesis, an investigation into the antimicrobial metabolites of Arctic and sub-Arctic marine invertebrate species is presented. Extracts of seven ascidian species, six sponge species, a soft-alcyonid coral and a bryozoan species...

  6. Experimental approach toward understanding the role of meiofauna in a detritus based marine food web

    International Nuclear Information System (INIS)

    The rate of detrital degradation was measured in three model systems maintained in chemostats. Each 1 l reaction vessel contained natural sediment carefully removed from the surface of a salt marsh at low tide. Alternate freezing and thawing killed indigenous organisms in the substrate. At the beginning of each experiment 14C labeled Zostera detritus and filtered (32P as a tracer indicated that 2 of the 3 meiofaunal species and their food were not consumed or assimilated in sufficient quantity to be major constituents of the diet of Capitella

  7. Population regulation and role of mesozooplankton in shaping marine pelagic food webs

    DEFF Research Database (Denmark)

    Kiørboe, Thomas

    1998-01-01

    Copepods constitute the majority of the mesozooplankton in the oceans. By eating and being eaten copepods have implications for the flow of matter and energy in the pelagic environment. I first consider population regulation mechanisms in copepods by briefly reviewing estimates of growth and mort......Copepods constitute the majority of the mesozooplankton in the oceans. By eating and being eaten copepods have implications for the flow of matter and energy in the pelagic environment. I first consider population regulation mechanisms in copepods by briefly reviewing estimates of growth...... activity for plankton food webs, particularly their role in retarding vertical fluxes and, thus, the loss of material from the euphotic zone...

  8. Quick Change of Marine Environment with Ecological Response in the Arctic Ocean%北冰洋环境快速变化与生态响应

    Institute of Scientific and Technical Information of China (English)

    何剑锋; 张芳

    2012-01-01

    随着全球变暖的加剧,北冰洋环境正在发生快速变化,水温升高、夏季海冰覆盖面积和海冰储量下降、淡水输入增加、盐度下降、海水酸化现象初现,导致原本依托海冰生存的北冰洋生态系统遭受前所未有的冲击.已有研究表明,与冰相关生物的生存状况正在恶化,初级生产者个体呈现小型化趋势,冰藻减少影响底栖生物产量,亚北极种入侵.由于北极环境和生态系统变化远超预期,而人类对生态系统、特别是北冰洋中心区的了解非常有限,如何尽快建 立观测体系、加强对生态系统的了解、预测潜在的变化成为未来的重要课题.%The environment of Arctic Ocean are changing quickly with the global warming, e. g., the increase of water temperature and the descent of water salinity, the decrease of ice coverage and ice volume in summer, the increase of fresh water influx, and the occurrence of sea water acidification. These changes significantly influence the ice-associated ecosystem. The previous studies suggest that the habitats of the ice-associated organisms turn worse, the size of the primary producers become smaller, the decrease of ice algae decline the production of benthos, and the invasion of sub-Arctic species influence the local species. Because the variations of Arctic Ocean environment and ecosystem exceed greatly what we expected and the knowledge is limited, a most important task for us in the coming years is to improve the observation systems and the forecasting capability of the potential changes.

  9. Marine reservoir corrections for bowhead whale radiocarbon age determinations

    International Nuclear Information System (INIS)

    Twenty-two pairs of radiocarbon dates on driftwood and bowhead whale (Balaena mysticetus) bones from raised beaches, dates on whale bone and terrestrial plant detritus from a stratigraphic section, and 25 additional dates on whale bones from the lowest (≤ 1 ka BP) raised beaches in the eastern Canadian Arctic suggest that a marine reservoir correction of about -200 years is appropriate for normalized age determinations on bone collagen from the bowhead whale in this region. This is less than the correction (-400 years) normally applied to carbonate shells of marine molluscs from this region. The carbon in bowhead collagen appears to be derived from the whales' zooplankton food rather than from marine bicarbonate. (author). 39 refs., 1 tab., 3 figs

  10. Arctic Ocean

    Science.gov (United States)

    Parkinson, Claire L.; Zukor, Dorothy J. (Technical Monitor)

    2000-01-01

    The Arctic Ocean is the smallest of the Earth's four major oceans, covering 14x10(exp 6) sq km located entirely within the Arctic Circle (66 deg 33 min N). It is a major player in the climate of the north polar region and has a variable sea ice cover that tends to increase its sensitivity to climate change. Its temperature, salinity, and ice cover have all undergone changes in the past several decades, although it is uncertain whether these predominantly reflect long-term trends, oscillations within the system, or natural variability. Major changes include a warming and expansion of the Atlantic layer, at depths of 200-900 m, a warming of the upper ocean in the Beaufort Sea, a considerable thinning (perhaps as high as 40%) of the sea ice cover, a lesser and uneven retreat of the ice cover (averaging approximately 3% per decade), and a mixed pattern of salinity increases and decreases.

  11. Arctic Shipping

    DEFF Research Database (Denmark)

    Hansen, Carsten Ørts; Grønsedt, Peter; Lindstrøm Graversen, Christian;

    maritime industries (including shipping, offshore energy, ports, and maritime service and equipment suppliers) as well as addresses topics that cut across maritime industries (regulation and competitiveness). The topics and narrower research questions addressed in the initiative were developed in close......, the latter aiming at developing key concepts and building up a basic industry knowledge base for further development of CBS Maritime research and teaching. This report attempts to map the opportunities and challenges for the maritime industry in an increasingly accessible Arctic Ocean...

  12. An assessment of seabird influence on Arctic coastal benthic communities

    Science.gov (United States)

    Zmudczyńska-Skarbek, Katarzyna; Balazy, Piotr; Kuklinski, Piotr

    2015-04-01

    It is well recognized that seabirds, particularly those nesting in coastal colonies, can provide significant nutrient enrichment to Arctic terrestrial ecosystems. However, little is known about the fate of bird-derived nutrients that return to the marine environment and potentially concentrate below the colonies. To attempt to assess the influence of this potential nutrient enrichment of the coastal benthic community, samples of macroalgae, sea urchins (mainly algivores), and hermit crabs (scavengers) were collected at two Arctic localities (Spitsbergen), (1) below a mixed colony of guillemots and kittiwakes, and (2) in an adjacent geomorphologically similar location not influenced by the seabird colony. A much higher nitrogen stable isotope ratio (δ15N) and total nitrogen content were found in terrestrial plants sampled below the colony than away from it. In benthic macroalgae, however, there were no δ15N differences. This might result from the timing of an intensive growth period in macroalgae in late winter/early spring, when there is little or no runoff from the land, and/or ornithogenic nutrients being directly incorporated by phytoplankton. Sea urchins showed higher δ15N and total N in the control site comparing to the colony-influenced area, suggesting differential food sources in their diet and a role of scavenging/carnivory on higher trophic levels there. Opportunistically feeding hermit crabs showed δ15N and total N enrichment below the seabird colony, suggesting dependence on detritus derived from food chains originating from pelagic producers. Our results indicate that seabirds in the Arctic may fertilize coastal benthic communities through pelagic-benthic coupling, while having no direct impact on bottom primary production.

  13. Fishing inside or outside? A case studies analysis of potential spillover effect from marine protected areas, using food web models

    Science.gov (United States)

    Colléter, Mathieu; Gascuel, Didier; Albouy, Camille; Francour, Patrice; Tito de Morais, Luis; Valls, Audrey; Le Loc'h, François

    2014-11-01

    Marine protected areas (MPAs) are implemented worldwide as an efficient tool to preserve biodiversity and protect ecosystems. We used food web models (Ecopath and EcoTroph) to assess the ability of MPAs to reduce fishing impacts on targeted resources and to provide biomass exports for adjacent fisheries. Three coastal MPAs: Bonifacio and Port-Cros (Mediterranean Sea), and Bamboung (Senegalese coast), were used as case studies. Pre-existing related Ecopath models were homogenized and ecosystem characteristics were compared based on network indices and trophic spectra analyses. Using the EcoTroph model, we simulated different fishing mortality scenarios and assessed fishing impacts on the three ecosystems. Lastly, the potential biomass that could be exported from each MPA was estimated. Despite structural and functional trophic differences, the three MPAs showed similar patterns of resistance to simulated fishing mortalities, with the Bonifacio case study exhibiting the highest potential catches and a slightly inferior resistance to fishing. We also show that the potential exports from our small size MPAs are limited and thus may only benefit local fishing activities. Based on simulations, their potential exports were estimated to be at the same order of magnitude as the amount of catch that could have been obtained inside the reserve. In Port Cros, the ban of fishing inside MPA could actually allow for improved catch yields outside the MPA due to biomass exports. This was not the case for the Bonifacio site, as its potential exports were too low to offset catch losses. This insight suggests the need for MPA networks and/or sufficiently large MPAs to effectively protect juveniles and adults and provide important exports. Finally, we discuss the effects of MPAs on fisheries that were not considered in food web models, and conclude by suggesting possible improvements in the analysis of MPA efficiency.

  14. Arctic parasitology: why should we care?

    Science.gov (United States)

    Davidson, Rebecca; Simard, Manon; Kutz, Susan J; Kapel, Christian M O; Hamnes, Inger S; Robertson, Lucy J

    2011-06-01

    The significant impact on human and animal health from parasitic infections in tropical regions is well known, but parasites of medical and veterinary importance are also found in the Arctic. Subsistence hunting and inadequate food inspection can expose people of the Arctic to foodborne parasites. Parasitic infections can influence the health of wildlife populations and thereby food security. The low ecological diversity that characterizes the Arctic imparts vulnerability. In addition, parasitic invasions and altered transmission of endemic parasites are evident and anticipated to continue under current climate changes, manifesting as pathogen range expansion, host switching, and/or disease emergence or reduction. However, Arctic ecosystems can provide useful models for understanding climate-induced shifts in host-parasite ecology in other regions.

  15. EROD activity and stable isotopes in seabirds to disentangle marine food web contamination after the Prestige oil spill

    Energy Technology Data Exchange (ETDEWEB)

    Velando, Alberto, E-mail: avelando@uvigo.e [Departamento de Ecoloxia e Bioloxia Animal, Facultade de Ciencias, Universidade de Vigo, Campus As Lagoas, 36310 Vigo (Spain); Munilla, Ignacio [Departamento de Botanica, Facultade de Farmacia, Universidade de Santiago de Compostela, Santiago de Compostela (Spain); Lopez-Alonso, Marta [Departamento de Patoloxia Animal, Facultade de Veterinaria, Universidade de Santiago de Compostela, Lugo (Spain); Freire, Juan [Grupo de Recursos Marinos y Pesquerias Universidade da Coruna, A Coruna (Spain); Perez, Cristobal [Departamento de Ecoloxia e Bioloxia Animal, Facultade de Ciencias, Universidade de Vigo, Campus As Lagoas, 36310 Vigo (Spain)

    2010-05-15

    In this study, we measured via surgical sampling hepatic EROD activity in yellow-legged gulls from oiled and unoiled colonies, 17 months after the Prestige oil spill. We also analyzed stable isotope composition in feathers of the biopsied gulls, in an attempt to monitor oil incorporation into marine food web. We found that yellow-legged gulls in oiled colonies were being exposed to remnant oil as shown by hepatic EROD activity levels. EROD activity was related to feeding habits of individual gulls with apparent consequences on delayed lethality. Capture-recapture analysis of biopsied gulls suggests that the surgery technique did not affect gull survival, giving support to this technique as a monitoring tool for oil exposure assessment. Our study highlights the combination of different veterinary, toxicological and ecological methodologies as a useful approach for the monitoring of exposure to remnant oil after a large oil spill. - Two years after Prestige oil spill, seabirds were exposed to remnant oil related to their feeding habits with consequences on delayed lethality.

  16. Trophic magnification of polybrominated diphenyl ethers in the marine food web from coastal area of Bohai Bay, North China.

    Science.gov (United States)

    Shao, Mihua; Tao, Ping; Wang, Man; Jia, Hongliang; Li, Yi-Fan

    2016-06-01

    Trophic transfer of polybrominated diphenyl ethers (PBDEs) in aquatic ecosystems is an important criterion for assessing their environmental risk. This study analyzed 13 PBDEs in marine organisms collected from coastal area of Bohai Bay, China. The concentrations of total PBDEs (Σ13PBDEs) ranged from 12 ± 1.1 ng/g wet weight (ww) to 230 ± 54 ng/g ww depending on species. BDE-47 was the predominant compound, with a mean abundance of 20.21 ± 12.97% of total PBDEs. Stable isotopic ratios of carbon (δ(13)C) and nitrogen (δ(15)N) were analyzed to determine the food web structure and trophic level respectively. Trophic magnification factors (TMFs) of PBDEs were assessed as the slope of lipid equivalent concentrations regressed against trophic levels. Significant positive relationships were found for Σ13PBDEs and eight PBDE congeners (BDE-28, BDE-47, BDE-49, BDE-66, BDE-85, BDE-99, BDE-100 and BDE-154). Monte-Carlo simulations showed that the probabilities of TMF >1 were 100% for Σ13PBDEs, BDE-47, BDE-85, BDE-99 and BDE-100, 99% for DE-28, BDE-49, BDE-66 and BDE-154, 94% for BDE-153, and 35% for BDE-17.

  17. EROD activity and stable isotopes in seabirds to disentangle marine food web contamination after the Prestige oil spill

    International Nuclear Information System (INIS)

    In this study, we measured via surgical sampling hepatic EROD activity in yellow-legged gulls from oiled and unoiled colonies, 17 months after the Prestige oil spill. We also analyzed stable isotope composition in feathers of the biopsied gulls, in an attempt to monitor oil incorporation into marine food web. We found that yellow-legged gulls in oiled colonies were being exposed to remnant oil as shown by hepatic EROD activity levels. EROD activity was related to feeding habits of individual gulls with apparent consequences on delayed lethality. Capture-recapture analysis of biopsied gulls suggests that the surgery technique did not affect gull survival, giving support to this technique as a monitoring tool for oil exposure assessment. Our study highlights the combination of different veterinary, toxicological and ecological methodologies as a useful approach for the monitoring of exposure to remnant oil after a large oil spill. - Two years after Prestige oil spill, seabirds were exposed to remnant oil related to their feeding habits with consequences on delayed lethality.

  18. Extraordinarily high spider densities on islands: flow of energy from the marine to terrestrial food webs and the absence of predation.

    Science.gov (United States)

    Polis, G A; Hurd, S D

    1995-01-01

    Some islands in the Gulf of California support very high densities of spiders. Spider density is negatively correlated with island size; many small islands support 50-200 spiders per m3 of cactus. Energy for these spiders comes primarily from the ocean and not from in situ productivity by land plants. We explicitly connect the marine and terrestrial systems to show that insular food webs represent one endpoint of the marine web. We describe two conduits for marine energy entering these islands: shore drift and seabird colonies. Both conduits are related to island area, having a much stronger effect on smaller islands. This asymmetric effect helps to explain the exceptionally high spider densities on small islands. Although productivity sets the maximal potential densities, predation (by scorpions) limits realized spider abundance. Thus, prey availability and predation act in concert to set insular spider abundance. PMID:7753815

  19. Fate of mercury in the Arctic (FOMA)

    DEFF Research Database (Denmark)

    Skov, H.; Christensen, J.; Asmund, G.;

    This report is the final reporting of the project FONA, funded by the Danish Environmental Protection Agency with means from the MIKA/DANCEA funds for Environmental Support to the Arctic Region. The aim of the project is to study the intercompartment mercury transport chain in the arctic area. From...... atmospheric deposition of mercury on sea surfaces to uptake in marine organisms, bio-accumulation, and finally mercury levels in mammals. The studies in the project are focused on the behaviour of mercury during the spring period where special phenomena lead to an enhanced deposition of mercury in the Arctic...... environment, at a time where the marine ecosystem is particularly active. The studies also include a comprehensive time trend study of mercury in top carnivore species. Each of these studies contributes towards establishing the knowledge necessary to develop a general model for transport and uptake of mercury...

  20. Effect of preservatives for food grade C-Phycoerythrin, isolated from marine cyanobacteria Pseudanabaena sp.

    Science.gov (United States)

    Mishra, Sanjiv K; Shrivastav, Anupama; Pancha, Imran; Jain, Deepti; Mishra, Sandhya

    2010-12-01

    C-Phycoerythrin is water soluble red color chromo-protein, which is used as a natural food colorant. The effect of selected edible preservatives like citric acid, sodium chloride, sucrose and calcium chloride on the stability of C-Phycoerythrin at 0±5°C and 35±5°C was studied in aqueous solution. Experiment was carried out to select a stabilizing agent having Hofmeister series behavior acting on hydrophobic interactions. The denaturation of phycoerythrin with urea as denaturant and effect of different pH on C-Phycoerythrin was studied. Citric acid (4 mg/ml) was observed to be one of the best preservative for C-Phycoerythrin at 35±5°C and 0±5°C in aqueous solution for 45 days. Citric acid was able to maintain the stability of C-Phycoerythrin in the solution. The amount of C-Phycoerythrin left in the solution containing citric acid after 30 and 45 days was 46 and 37.8% respectively at higher temperature.

  1. Carotenoids in Marine Animals

    OpenAIRE

    Takashi Maoka

    2011-01-01

    Marine animals contain various carotenoids that show structural diversity. These marine animals accumulate carotenoids from foods such as algae and other animals and modify them through metabolic reactions. Many of the carotenoids present in marine animals are metabolites of β-carotene, fucoxanthin, peridinin, diatoxanthin, alloxanthin, and astaxanthin, etc. Carotenoids found in these animals provide the food chain as well as metabolic pathways. In the present review, I will describe marine a...

  2. Trace element concentrations and gastrointestinal parasites of Arctic terns breeding in the Canadian High Arctic.

    Science.gov (United States)

    Provencher, J F; Braune, B M; Gilchrist, H G; Forbes, M R; Mallory, M L

    2014-04-01

    Baseline data on trace element concentrations are lacking for many species of Arctic marine birds. We measured essential and non-essential element concentrations in Arctic tern (Sterna paradisaea) liver tissue and brain tissue (mercury only) from Canada's High Arctic, and recorded the presence/absence of gastrointestinal parasites during four different phases of the breeding season. Arctic terns from northern Canada had similar trace element concentrations to other seabird species feeding at the same trophic level in the same region. Concentrations of bismuth, selenium, lead and mercury in Arctic terns were high compared to published threshold values for birds. Selenium and mercury concentrations were also higher in Arctic terns from northern Canada than bird species sampled in other Arctic areas. Selenium, mercury and arsenic concentrations varied across the time periods examined, suggesting potential regional differences in the exposure of biota to these elements. For unknown reasons, selenium concentrations were significantly higher in birds with gastrointestinal parasites as compared to those without parasites, while bismuth concentrations were higher in Arctic terns not infected with gastrointestinal parasites.

  3. Isolation and characteristics of one marine psychrotrophic cellulase-generating bacterium Ar/w/b/75°/10/5 from Chuckchi Sea, Arctic

    Institute of Scientific and Technical Information of China (English)

    曾胤新; 陈波

    2002-01-01

    Microorganisms living in polar zones play an important part as the potential source of organic activity materials with low temperature characteristics in the biotechnological applications. A psychrotrophic bacterium (strain Ar/w/b/75°/10/5), producing cellulase at low temperatures during late-exponential and early-stationary phases of cell growth, was isolated from sea ice-covered surface water in Chuckchi Sea, Arctic. This bacterium, with rod cells, was Gram-negative, slightly halophilic. Colony growing on agar plate was in black. Optimum growth temperature was 15℃. No cell growth was observed at 35℃ or above. Optimum salt concentration for cell growth was between 2 and 3 % of sodium chloride in media. Maximal cellulase activity was detected at a temperature of 35℃ and pH8. Cellulase was irreversibly inactivated when incubated at 55℃ within 30 min. Enzyme can be kept stable at the temperature no higher than 25℃. Of special interest was that this bacterium produced various extracellular enzymes including cellulase, amylase, agar hydrolase and protease, at low or moderate temperature conditions, which is certainly of it potential value for applications.

  4. 3D seismic imaging of marine gas hydrates in Arctic sediments of the Vestnesa Ridge off the W-Svalbard margin

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, C.J.; Bunz, S.; Hustoft, S.; Mienert, J. [Tromso Univ., Tromso (Norway). Dept. of Geology

    2008-07-01

    A gas hydrate and fluid flow dominated sediment drift system at the Vestnesa Ridge offshore W-Svalbard was characterized using high-resolution 3-D seismic data. This ridge represents one of the northernmost gas hydrate provinces that exist along Arctic continental margins. Detailed images revealed seabed pockmarks connected to sub-seabed chimneys that pierce through stratified sediments. The base of the gas hydrate stability zone (BGHSZ) is evident at about 200 ms TWT below seafloor as indicated by a bottom simulating reflector. Increased amplitudes beneath the BGHSZ indicate the existence of large amounts of free gas in the sediment pore space. Variations in lateral amplitude indicate a geological control on the free gas distributions rather than pressure and temperature conditions. The seismic surveys also revealed the internal structure of the acoustic chimneys that act as conduits for fluids and gases rising from greater depth to the seabed. It was suggested that the combination of authigenic carbonate and gas hydrate formation may cause shallow high-reflectivity above the BGHSZ. The fluid flow processes that result in the multifracturing of sediments play a significant role in the evolution of the chimney structures in a gas hydrated sedimentary environment. 21 refs., 7 figs.

  5. Carotenoids in Marine Animals

    Directory of Open Access Journals (Sweden)

    Takashi Maoka

    2011-02-01

    Full Text Available Marine animals contain various carotenoids that show structural diversity. These marine animals accumulate carotenoids from foods such as algae and other animals and modify them through metabolic reactions. Many of the carotenoids present in marine animals are metabolites of β-carotene, fucoxanthin, peridinin, diatoxanthin, alloxanthin, and astaxanthin, etc. Carotenoids found in these animals provide the food chain as well as metabolic pathways. In the present review, I will describe marine animal carotenoids from natural product chemistry, metabolism, food chain, and chemosystematic viewpoints, and also describe new structural carotenoids isolated from marine animals over the last decade.

  6. Food and water security issues in Russia II: Water security in general population of Russian Arctic, Siberia and Far East, 2000–2011

    OpenAIRE

    Dudarev, Alexey A.; Eugenia V. Dushkina; Sladkova, Yuliya N; Alloyarov, Pavel R.; Chupakhin, Valeriy S.; Dorofeyey, Vitaliy M.; Tatijana A. Kolesnikova; Fridman, Kirill B.; Evengård, Birgitta; Nilsson, Lena Maria

    2013-01-01

    Background. Poor state of water supply systems, shortage of water purification facilities and disinfection systems, low quality of drinking water generally in Russia and particularly in the regions of the Russian Arctic, Siberia and Far East have been defined in the literature. However, no standard protocol of water security assessment has been used in the majority of studies.Study design and methods. Uniform water security indicators collected from Russian official statistical sources for th...

  7. Dietary exposure to persistent organic pollutants and metals among Inuit and Chukchi in Russian Arctic Chukotka

    Directory of Open Access Journals (Sweden)

    Alexey A. Dudarev

    2012-07-01

    Full Text Available Objectives. The general aim was to assess dietary exposure to selected persistent organic pollutants (POPs and metals among Eskimo (Inuit and Chukchi of the Chukotka Peninsula of the Russian Arctic, and to establish recommendations for exposure risk reduction. Study design. A cross-sectional evaluation of nutritional patterns of coastal and inland indigenous peoples of the Chukotka Autonomous Okrug (in 2001–2003; assessment of the levels of persistent toxic substances (PTSs in traditional foods and their comparison to Russian food safety limits; the identification of local sources of food contamination; and the recommendation and implementation of risk management measures. Methods. Community-based dietary survey of self reported food frequencies (453 persons, chemical analyses (POPs and metals of local foods and indoor matters (397 samples, substantiation of recommendations for daily (weekly, monthly intakes of traditional food. Results. POPs in traditional food items are generally below the Russian food safety limits except marine mammal fat, while Hg and Cd are high mainly in mammal viscera. Lead is relatively low in tissues of all animals studied. For the Chukotka coastal communities, seals constitute the principal source of the whole suite of PTSs considered. Consumption restrictions are recommended for marine and freshwater fish, some wild meats (waterfowl and seal, fats (whale and seal, liver (most animals and kidney (reindeer, walrus and seal. Evidence is presented that contamination of foodstuffs may be significantly increased during storing/processing/cooking of food due to indoor and outdoor environmental conditions. Conclusions. Based on the analytical findings and the local PTSs sources identified, guidelines on food safety are suggested, as well as measures to reduce food contamination and domestic and local sources. Important and urgent remedial actions are recommended to minimize PTSs environmental and domestic contamination

  8. Arctic warming will promote Atlantic-Pacific fish interchange

    Science.gov (United States)

    Wisz, M. S.; Broennimann, O.; Grønkjær, P.; Møller, P. R.; Olsen, S. M.; Swingedouw, D.; Hedeholm, R. B.; Nielsen, E. E.; Guisan, A.; Pellissier, L.

    2015-03-01

    Throughout much of the Quaternary Period, inhospitable environmental conditions above the Arctic Circle have been a formidable barrier separating most marine organisms in the North Atlantic from those in the North Pacific. Rapid warming has begun to lift this barrier, potentially facilitating the interchange of marine biota between the two seas. Here, we forecast the potential northward progression of 515 fish species following climate change, and report the rate of potential species interchange between the Atlantic and the Pacific via the Northwest Passage and the Northeast Passage. For this, we projected niche-based models under climate change scenarios and simulated the spread of species through the passages when climatic conditions became suitable. Results reveal a complex range of responses during this century, and accelerated interchange after 2050. By 2100 up to 41 species could enter the Pacific and 44 species could enter the Atlantic, via one or both passages. Consistent with historical and recent biodiversity interchanges, this exchange of fish species may trigger changes for biodiversity and food webs in the North Atlantic and North Pacific, with ecological and economic consequences to ecosystems that at present contribute 39% to global marine fish landings.

  9. The progress in the study of Arctic pack ice ecology

    Institute of Scientific and Technical Information of China (English)

    何剑锋; 王桂忠; 蔡明红; 李少菁

    2004-01-01

    The sea ice community plays an important role in the Arctic marine ecosystem. Because of the predicted environmental changes in the Arctic environment and specifically related to sea ice, the Arctic pack ice biota has received more attention in recent years using modern ice-breaking research vessels. Studies show that the Arctic pack ice contains a diverse biota and besides ice algae, the bacterial and protozoan biomasses can be high. Surprisingly high primary production values were observed in the pack ice of the central Arctic Ocean. Occasionally biomass maximum were discovered in the interior of the ice floes, a habitat that had been ignored in most Arctic studies. Many scientific questions, which deserve special attention, remained unsolved due to logistic limitations and the sea ice characteristics. Little is know about the pack ice community in the central Arctic Ocean. Almost no data exists from the pack ice zone for the winter season. Concerning the abundance of bacteria and protozoa, more studies are needed to understand the microbial network within the ice and its role in material and energy flows. The response of the sea ice biota to global change will impact the entire Arctic marine ecosystem and a long-term monitoring program is needed. The techniques, that are applied to study the sea ice biota and the sea ice ecology, should be improved.

  10. PAST Gateways (Palaeo-Arctic Spatial and Temporal Gateways): Introduction and overview

    Science.gov (United States)

    Ó Cofaigh, Colm; Briner, Jason P.; Kirchner, Nina; Lucchi, Renata G.; Meyer, Hanno; Kaufman, Darrell S.

    2016-09-01

    This special issue relates to the Second International Conference of the PAST Gateways (Palaeo-Arctic Spatial and Temporal Gateways) network which was held in Trieste, Italy in 2014. Twenty five papers are included and they address topics under four main themes: (1) The growth and decay of Arctic ice sheets; (2) Arctic sea ice and palaeoceanography; (3) Terrestrial Arctic environments and permafrost change; and (4) Holocene Arctic environmental change. Geographically the focus is circum-Arctic; the special issue includes detailed regional studies from Greenland, Scandinavia, Russia, and Arctic North America and the adjoining seas, as well as a series of synthesis-type, review papers on Fennoscandian Ice Sheet deglaciation and Holocene Arctic palaeo-climate change. The methodologies employed are diverse and include marine sediment core and geophysical investigations, terrestrial glacial geology and geomorphology, isotopic analysis of ground ice, palaeo-ecological analysis of lacustrine and terrestrial sedimentary archives, geochronology and numerical ice sheet modeling.

  11. The Arctic Report Card: Communicating the State of the Rapidly Changing Arctic to a Diverse Audience via the Worldwide Web

    Science.gov (United States)

    Jeffries, M. O.; Richter-Menge, J.; Overland, J. E.; Soreide, N. N.

    2013-12-01

    Rapid change is occurring throughout the Arctic environmental system. The goal of the Arctic Report Card is to communicate the nature of the many changes to a diverse audience via the Worldwide Web. First published in 2006, the Arctic Report Card is a peer-reviewed publication containing clear, reliable and concise scientific information on the current state of the Arctic environment relative to observational records. Available only online, it is intended to be an authoritative source for scientists, teachers, students, decision-makers, policy-makers and the general public interested in the Arctic environment and science. The Arctic Report Card is organized into five sections: Atmosphere; Sea Ice & Ocean; Marine Ecosystem; Terrestrial Ecosystem; Terrestrial Cryosphere. Arctic Report Card 2012, the sixth annual update, comprised 20 essays on physical and biological topics prepared by an international team of 141 scientists from 15 different countries. For those who want a quick summary, the Arctic Report Card home page provides highlights of key events and findings, and a short video that is also available on YouTube. The release of the Report Card each autumn is preceded by a NOAA press release followed by a press conference, when the Web site is made public. The release of Arctic Report Card 2012 at an AGU Fall Meeting press conference on 5 December 2012 was subsequently reported by leading media organizations. The NOAA Arctic Web site, of which the Report Card is a part, is consistently at the top of Google search results for the keyword 'arctic', and the Arctic Report Card Web site tops search results for keyword "arctic report" - pragmatic indications of a Web site's importance and popularity. As another indication of the Web site's impact, in December 2012, the month when the 2012 update was released, the Arctic Report Card Web site was accessed by 19,851 unique sites in 105 countries, and 4765 Web site URLs referred to the Arctic Report Card. The 2012 Arctic

  12. Assessing determinants of maternal blood concentrations for persistent organic pollutants and metals in the eastern and western Canadian Arctic

    International Nuclear Information System (INIS)

    Aboriginal peoples in the Canadian Arctic are exposed to persistent organic pollutants (POPs) and metals mainly through their consumption of a traditional diet of wildlife items. Recent studies indicate that many human chemical levels have decreased in the north, likely due to a combination of reduced global chemical emissions, dietary shifts, and risk mitigation efforts by local health authorities. Body burdens for chemicals in mothers can be further offset by breastfeeding, parity, and other maternal characteristics. We have assessed the impact of several dietary and maternal covariates following a decade of awareness of the contaminant issue in northern Canada, by performing multiple stepwise linear regression analyses from blood concentrations and demographic variables for 176 mothers recruited from Nunavut and the Northwest Territories during the period 2005–2007. A significant aboriginal group effect was observed for the modeled chemicals, except for lead and cadmium, after adjusting for covariates. Further, blood concentrations for POPs and metals were significantly associated with at least one covariate of older age, fewer months spent breastfeeding, more frequent eating of traditional foods, or smoking during pregnancy. Cadmium had the highest explained variance (72.5%) from just two significant covariates (current smoking status and parity). Although Inuit participants from the Northwest Territories consumed more traditional foods in general, Inuit participants from coastal communities in Nunavut continued to demonstrate higher adjusted blood concentrations for POPs and metals examined here. While this is due in part to a higher prevalence of marine mammals in the eastern Arctic diet, it is possible that other aboriginal group effects unrelated to diet may also contribute to elevated chemical body burdens in Canadian Arctic populations. - Highlights: • In 2005–07, younger age was related to lower levels of chemicals in northern Canada. • Eastern

  13. Assessing determinants of maternal blood concentrations for persistent organic pollutants and metals in the eastern and western Canadian Arctic

    Energy Technology Data Exchange (ETDEWEB)

    Curren, Meredith S., E-mail: meredith.curren@hc-sc.gc.ca [Chemicals Surveillance Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 269 Laurier Avenue West, Ottawa, Ontario (Canada); Liang, Chun Lei, E-mail: chun.lei.liang@hc-sc.gc.ca [Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 50 Columbine Driveway, Tunney' s Pasture, Ottawa, Ontario (Canada); Davis, Karelyn, E-mail: karelyn.davis@hc-sc.gc.ca [Environmental Health Science and Research Bureau, Healthy Environments and Consumer Safety Branch, Health Canada, 50 Columbine Driveway, Tunney' s Pasture, Ottawa, Ontario (Canada); Kandola, Kami, E-mail: Kami_Kandola@gov.nt.ca [Government of the Northwest Territories, Yellowknife, Northwest Territories (Canada); Brewster, Janet, E-mail: jbrewster@gov.nu.ca [Government of Nunavut, Iqaluit, Nunavut (Canada); Potyrala, Mary, E-mail: mary_potyrala@yahoo.ca [Government of Nunavut, Iqaluit, Nunavut (Canada); Chan, Hing Man, E-mail: laurie.chan@uottawa.ca [Center for Advanced Research in Environmental Genomics, University of Ottawa, 20 Marie-Curie, Ottawa, Ontario (Canada)

    2015-09-15

    Aboriginal peoples in the Canadian Arctic are exposed to persistent organic pollutants (POPs) and metals mainly through their consumption of a traditional diet of wildlife items. Recent studies indicate that many human chemical levels have decreased in the north, likely due to a combination of reduced global chemical emissions, dietary shifts, and risk mitigation efforts by local health authorities. Body burdens for chemicals in mothers can be further offset by breastfeeding, parity, and other maternal characteristics. We have assessed the impact of several dietary and maternal covariates following a decade of awareness of the contaminant issue in northern Canada, by performing multiple stepwise linear regression analyses from blood concentrations and demographic variables for 176 mothers recruited from Nunavut and the Northwest Territories during the period 2005–2007. A significant aboriginal group effect was observed for the modeled chemicals, except for lead and cadmium, after adjusting for covariates. Further, blood concentrations for POPs and metals were significantly associated with at least one covariate of older age, fewer months spent breastfeeding, more frequent eating of traditional foods, or smoking during pregnancy. Cadmium had the highest explained variance (72.5%) from just two significant covariates (current smoking status and parity). Although Inuit participants from the Northwest Territories consumed more traditional foods in general, Inuit participants from coastal communities in Nunavut continued to demonstrate higher adjusted blood concentrations for POPs and metals examined here. While this is due in part to a higher prevalence of marine mammals in the eastern Arctic diet, it is possible that other aboriginal group effects unrelated to diet may also contribute to elevated chemical body burdens in Canadian Arctic populations. - Highlights: • In 2005–07, younger age was related to lower levels of chemicals in northern Canada. • Eastern

  14. Food and water security issues in Russia II: Water security in general population of Russian Arctic, Siberia and Far East, 2000–2011

    Directory of Open Access Journals (Sweden)

    Alexey A. Dudarev

    2013-12-01

    Full Text Available Background . Poor state of water supply systems, shortage of water purification facilities and disinfection systems, low quality of drinking water generally in Russia and particularly in the regions of the Russian Arctic, Siberia and Far East have been defined in the literature. However, no standard protocol of water security assessment has been used in the majority of studies. Study design and methods . Uniform water security indicators collected from Russian official statistical sources for the period 2000–2011 were used for comparison for 18 selected regions in the Russian Arctic, Siberia and Far East. The following indicators of water security were analyzed: water consumption, chemical and biological contamination of water reservoirs of Categories I and II of water sources (centralized – underground and surface, and non-centralized and of drinking water. Results . Water consumption in selected regions fluctuated from 125 to 340 L/person/day. Centralized water sources (both underground and surface sources are highly contaminated by chemicals (up to 40–80% and biological agents (up to 55% in some regions, mainly due to surface water sources. Underground water sources show relatively low levels of biological contamination, while chemical contamination is high due to additional water contamination during water treatment and transportation in pipelines. Non-centralized water sources are highly contaminated (both chemically and biologically in 32–90% of samples analyzed. Very high levels of chemical contamination of drinking water (up to 51% were detected in many regions, mainly in the north-western part of the Russian Arctic. Biological contamination of drinking water was generally much lower (2.5–12% everywhere except Evenki AO (27%, and general and thermotolerant coliform bacteria predominated in drinking water samples from all regions (up to 17.5 and 12.5%, correspondingly. The presence of other agents was much lower: Coliphages

  15. 荣成海洋食品网络营销成长初期对策研究%Countermeasures of the Early Growth of Network Marketing about Marine Food in Rongcheng

    Institute of Scientific and Technical Information of China (English)

    毕志明

    2015-01-01

    Marine food have long enjoyed a reputation in Rongcheng city. Rongcheng awarded the title“Chinese marine food city” by Food Industry Association in 2009. In the new internet era, how to innovate network thinking, build regional marine food brands, and make progress together with offline brand, have become the important task of adjusting structure and transformation development in Rongcheng. Based on the analysis on the current situation of marine food network marketing in Rongcheng, the regional marine food network marketing strategic is proposed.%荣成市海洋食品久负盛名,2009年被中国食品工业协会授予“中国海洋食品名城”称号。在互联网新时代,如何创新网络新思维,打造区域海洋食品网络品牌,与线下品牌齐头并进,成为荣成市转方式、调结构、转型发展的重要任务。通过分析网络营销发展现状,提出当前区域海洋食品网络营销策略建议。

  16. Phenotypic and phylogenetic evidence for the role of food and habitat in the assembly of communities of marine amphipods.

    Science.gov (United States)

    Best, Rebecca J; Stachowicz, John J

    2014-03-01

    The study of community assembly processes currently involves (a) longstanding questions about the relative importance of environmental filtering vs. niche partitioning in a wide range of ecosystems, and (b) more recent questions about methodology. The rapidly growing field of community phylogenetics has generated debate about the choice between functional traits and phylogenetic relationships for understanding species similarities, and has raised additional questions about the contribution of experimental vs. observational approaches to understanding evolutionary constraints on community assembly. In this study, we use traits, a phylogeny, and field surveys to identify the forces structuring communities of herbivorous marine amphipods and isopods living in adjacent seagrass and macroalgae. In addition, we compare our field results to a recently published mesocosm experiment that tested the effects of both trait and phylogenetic diversity on coexistence using the same species and system. With respect to community assembly processes, we found that environmental filtering was the dominant process in macroalgae habitats, that niche partitioning was the dominant process in seagrass habitats, and that the strength of these assembly mechanisms varied with seasonal fluctuations in environmental conditions and resource availability. These patterns are indicated by both phylogenetic relationships and trait distances, but the type of resources being partitioned in seagrass habitats can only be deciphered using trait data. Species coexisting in seagrass in the field differed not in their feeding niche but in traits related to microhabitat use, providing novel evidence of the relative importance of competition for food vs. habitat in structuring communities of phytophagous invertebrates. With respect to methodology, the results for seagrass habitats conflict with those obtained in mesocosms, where feeding trait diversity did promote coexistence and phylogenetic diversity had no

  17. A quantitative x-ray diffraction inventory of volcaniclastic inputs into the marine sediment archives off Iceland: a contribution to the Volcanoes in the Arctic System programme

    Directory of Open Access Journals (Sweden)

    Dennis D. Eberl

    2013-02-01

    Full Text Available This paper re-evaluates how well quantitative x-ray diffraction (qXRD can be used as an exploratory method of the weight percentage (wt% of volcaniclastic sediment, and to identify tephra events in marine cores. In the widely used RockJock v6 software programme, qXRD tephra and glass standards include the rhyodacite White River tephra (Alaska, a rhyolitic tephra (Hekla-4 and the basaltic Saksunarvatn tephra. Experiments of adding known wt% of tephra to felsic bedrock samples indicated that additions ≥10 wt% are accurately detected, but reliable estimates of lesser amounts are masked by amorphous material produced by milling. Volcaniclastic inputs range between 20 and 50 wt%. Primary tephra events are identified as peaks in residual qXRD glass wt% from fourth-order polynomial fits. In cores where tephras have been identified by shard counts in the >150 µm fraction, there is a positive correlation (validation with peaks in the wt% glass estimated by qXRD. Geochemistry of tephra shards confirms the presence of several Hekla-sourced tephras in cores B997-317PC1 and -319PC2 on the northern Iceland shelf. In core B997-338 (north-west Iceland, there are two rhyolitic tephras separated by ca. 100 cm with uncorrected radiocarbon dates on articulated shells of around 13 000 yr B.P. These tephras may be correlatives of the Borrobol and Penifiler tephras found in Scotland. The number of Holocene tephra events per 1000 yr was estimated from qXRD on 16 cores and showed a bimodal distribution with an increased number of events in both the late and early Holocene.

  18. Evaluation of poultry protein isolate as a food ingredient: physicochemical properties and sensory characteristics of marinated chicken breasts.

    Science.gov (United States)

    Khiari, Zied; Omana, Dileep A; Pietrasik, Zeb; Betti, Mirko

    2013-07-01

    The possibilities of replacing soy protein isolate (SPI) and reducing the amount of phosphate in marinated chicken breasts using poultry protein isolate (PPI) were investigated. PPI, prepared from mechanically separated turkey meat through the pH-shift technology, was used as a marinade ingredient for chicken breasts at 2 different concentrations (1.0% and 1.5%, w/w on a dry weight basis). Product characteristics were compared to samples marinated with salt, phosphate, or SPI. All the 5 treatments were subjected to instrumental and sensory analyses. Tumbling yield, drip, and cooking losses as well as expressible moisture showed that PPI can be used as a substitute for SPI in brine. The sensory analysis revealed that there were no differences among treatments in terms of appearance, color, flavor, saltiness, juiciness, tenderness, and overall acceptability of the marinated chicken breasts. However, chicken breasts marinated with phosphate had significantly higher aroma acceptability scores than those treated with 1% PPI.

  19. Trophic transfer of lead through a model marine four-level food chain: Tetraselmis suecica, Artemia franciscana, Litopenaeus vannamei, and Haemulon scudderi.

    Science.gov (United States)

    Soto-Jiménez, M F; Arellano-Fiore, C; Rocha-Velarde, R; Jara-Marini, M E; Ruelas-Inzunza, J; Páez-Osuna, F

    2011-08-01

    The objective of this investigation was to assess the transfer of lead (Pb) along an experimental, four-level food chain: Tetraselmis suecica (phytoplankton) → Artemia franciscana (crustacean, brine shrimp) → Litopenaeus vannamei (crustacean, white shrimp) → Haemulon scudderi (fish, grunt). T. suecica was exposed to a sublethal dose of Pb in solution and then used as the base of a marine food chain. Significant differences in Pb concentrations were found between exposed organisms of the different trophic levels and the control. Particularly, Pb concentrations in fish of the simulated trophic chain were two-to three times higher in the exposed specimens than in the control. Levels of Pb in phytoplankton showed a substantial increase with respect to the solution (level I), with bioconcentration factors averaging from 930 to 3630. In contrast, a strong decrease in Pb concentration from phytoplankton to zooplankton (level II) and from zooplankton to shrimp tissues (level III) was evidenced by bioaccumulation factors metal transfer observed in these two predators, Pb concentration in the grunt fish (level IV) was higher than in the shrimp (level III) (bioaccumulation factor >1.0). Some of the added Pb is transferred from the phytoplankton along the food chain, thus producing a net accumulation of Pb mainly in fish and, to a lesser extent, in shrimp tissues. Because Pb is one of the most pervasive contaminants in coastal ecosystems, its transference by way of diet and potential net accumulation in higher predators is of ecologic importance for marine life. In addition, because shrimp and adult Haemulon scudderi are commercially important resources, this issue is of particular relevance to the safety of marine products. PMID:21082317

  20. The cultivation of Acartia tonsa Dana for use as a live food source for marine fish larvae

    DEFF Research Database (Denmark)

    Støttrup, Josianne; Richardson, Katherine; Kirkegaard, Eskild;

    1986-01-01

    The marine calanoid copepod Acartia tonsa has been continuously cultivated in the laboratory at the Danish Institute for Fisheries and Marine Research for over 70 generations. A description of the cultivation procedures is presented in this paper. Adult copepods are maintained in 200–450-l tanks ...... and are fed the cryptophyte Rhodomonas baltica. The concentration of adult copepods is held between 50 and 100/l. Eggs are harvested daily and, on average, ca. 25 eggs are collected per female per day....

  1. Traditional and modern Greenlandic food - dietary composition, nutrients and contaminants

    DEFF Research Database (Denmark)

    Deutch, Bente; Dyerberg, Jørn; Pedersen, Henning Sloth;

    2007-01-01

    increase their frequency of these diseases. However, since the 1970s it has become evident that the marine-based Inuit diet also contains high levels of potentially toxic lipophilic organic pollutants and heavy metals. Since these two food related opposing health effects appear to be inseparable......, the phenomenon has been known as "The Arctic Dilemma". However, both the fatty acid composition and the contaminant levels vary in Greenlandic food items. Thus in principle it is possible to compose a diet where the benefits and risks are better balanced. Our objectives of this study were to compare traditional......OBJECTIVES: High levels of n-3 fatty acids and other nutrients in traditional Inuit food appear to provide some protection against the typical diseases of affluent industrialized societies: cardiovascular diseases and type 2 diabetes. An increased intake of imported food among Inuits will probably...

  2. 海洋仿生食品的综合生产加工%The comprehensive production and processing of marine bionic food

    Institute of Scientific and Technical Information of China (English)

    孙晓莲

    2013-01-01

      对国内外海洋仿生食品的生产加工及消费进行了论述,主要对模拟蟹肉、鱼丸、鱼豆腐、腰花肠、包心鱼丸等海洋仿生食品的生产加工进行了详细介绍。%The comprehensive production, processing and consume of marine bionic food at home and abroad were re-viewed in this paper. The imitation crab meat, fish balls, fish tofu, fish sausages, and stuffed fish balls were introduced in detail.

  3. 海洋鱼类摄食生态与食物网研究进展%Marine fish feeding ecology and food web:progress and perspectives

    Institute of Scientific and Technical Information of China (English)

    颜云榕; 卢伙胜; 金显仕

    2011-01-01

    This paper firstly summarized the experimental methods on marine fish feeding ecology and food web ,mainly including stomach contents analysis, stable isotope analysis, compound-specific stable isotope analysis and behavior methods, their development and current applications.Secondly, the progress and achievement of fish diet composition, foraging types, food consumption and distribution in body were introduced.The strategies of marine food web research based on traditional stomach contents analysis,focusing on simplified food web, developing in stable isotope analysis techniques and ecosystem modeling were also presented.Finally, the trends of marine fish feeding ecology and food web research were predicted;furthermore, the problems and deficiency of the development and research in this field in China were discussed.%首先总结归纳了海洋鱼类摄食生态与食物网研究中的实验方法,主要包括胃含物分析法、碳氮稳定同位素法、特定化合物同位素法等实验方法的发展历史和应用现状;随后介绍了海洋鱼类摄食生态与食物网最新研究进展和取得的成绩,主要包括海洋鱼类摄食生态中食物组成、摄食方式、摄食量和食物用于机体各种生命活动分配方式,以及海洋食物网研究中以传统胃含物分析法为基础、以简化食物网为核心,碳氮稳定同位素技术和生态系统模型的应用发展;最后,着重分析了我国海洋鱼类摄食生态和食物网研究中有待解决的问题,并对该领域今后的发展趋势进行了展望.

  4. Spatial Distribution of Methanesulphonic Acid in the Arctic Aerosol Collected during the Chinese Arctic Research Expedition

    Directory of Open Access Journals (Sweden)

    Peipei Ye

    2015-05-01

    Full Text Available Methanesulphonic acid (MSA, mainly derived from marine biogenic emissions has been frequently used to estimate the marine biogenic contribution. However, there are few reports on MSA over the Arctic Ocean, especially the central Arctic Ocean. Here, we analyzed MSA in aerosol samples collected over the ocean and seas during the Chinese Arctic Research Expedition (CHINARE 2012 using ion chromatography. The aerosol MSA concentrations over the Arctic Ocean varied considerably and ranged from non-detectable (ND to 229 ng/m3, with an average of 27 ± 54 ng/m3 (median: 10 ng/m3. We found the distribution of aerosol MSA exhibited an obvious regional variation, which was affected by biotic and abiotic factors. High values were generally observed in the Norwegian Sea; this phenomenon was attributed to high rates of phytoplankton primary productivity and dimethylsulfide (DMS fluxes in this region. Concentrations over the pack ice region in the central Arctic Ocean were generally lower than over the open waters at the ice edge in the Chukchi Sea. This difference was the mainly caused by sea ice. In addition, we found that higher MSA concentrations were associated with warmer sea surface temperature (SST.

  5. Evaluation of the “fishing down marine food web” process in the north-west of Persian Gulf (Khuzestan Province) during the period of 2002-2011

    Institute of Scientific and Technical Information of China (English)

    MASHJOOR Sakineh; KAMRANI Ehsan

    2015-01-01

    The worldwide increase in commercial fisheries and its impact on ecosystems as well as inefficient fishery management have led to overfishing and frequent breakdown of traditional fish stocks. In this context, an analysis of Khuzestan inshore fisheries data covering the years 2002–2011, was conducted in reliance on testing for occurrence of the fishing down marine food webs (FDMFW) phenomenon in the North of Persian Gulf Large Marine Ecosystem (LME). In this study, the mean trophic level (mTL) and the fishing-in-balance (FIB)-index of Khuzestan landings during this period of time were estimated using the trophic level of 47 fishery resources. Increase in total landings (Y) was observed, which explained the high fishing yield in major fishery resources (especially demersal). Moreover, the moderates decreasing trend in mTL per decade, and the increasing trend in FIB-index were observed. The status of fishery resources in Khuzestan inshore waters (under exploited but not overexploited), the rise inY, FIB and slightly drop in mTL can be considered as indirect indicators of the fishing impacts on the trophic structure of marine communities. Based on this result, probability occurrence of FDMFW process in Khuzestan inshore waters is low to some extent. However, we suggest that the goal of management programs in Khuzestan inshore waters should prevent the continuance of this trend in the long-term using an ecosystem-based approach.

  6. High tolerance of protozooplankton to ocean acidification in an Arctic coastal plankton community

    Science.gov (United States)

    Aberle, N.; Schulz, K. G.; Stuhr, A.; Ludwig, A.; Riebesell, U.

    2012-09-01

    Impacts of ocean acidification (OA) on marine biota have been observed in a wide range of marine systems. We used a mesocosm approach to study the response of a high Arctic coastal protozooplankton (PZP in the following) community during the post-bloom period in the Kongsfjorden (Svalbard) to direct and indirect effects of high pCO2/low pH. We found almost no direct effects of OA on PZP composition and diversity. Both, the relative shares of ciliates and heterotrophic dinoflagellates as well as the taxonomic composition of protozoans remained unaffected by changes in pCO2/pH. The different pCO2 treatments did not have any effect on food availability and phytoplankton composition and thus no indirect effects e.g. on the total carrying capacity and phenology of PZP could be observed. Our data points at a high tolerance of this Arctic PZP community to changes in pCO2/pH. Future studies on the impact of OA on plankton communities should include PZP in order to test whether the observed low sensitivity of protozoans to OA is typical for coastal communities where changes in seawater pH occur frequently.

  7. High tolerance of protozooplankton to ocean acidification in an Arctic coastal plankton community

    Directory of Open Access Journals (Sweden)

    N. Aberle

    2012-09-01

    Full Text Available Impacts of ocean acidification (OA on marine biota have been observed in a wide range of marine systems. We used a mesocosm approach to study the response of a high Arctic coastal protozooplankton (PZP in the following community during the post-bloom period in the Kongsfjorden (Svalbard to direct and indirect effects of high pCO2/low pH. We found almost no direct effects of OA on PZP composition and diversity. Both, the relative shares of ciliates and heterotrophic dinoflagellates as well as the taxonomic composition of protozoans remained unaffected by changes in pCO2/pH. The different pCO2 treatments did not have any effect on food availability and phytoplankton composition and thus no indirect effects e.g. on the total carrying capacity and phenology of PZP could be observed. Our data points at a high tolerance of this Arctic PZP community to changes in pCO2/pH. Future studies on the impact of OA on plankton communities should include PZP in order to test whether the observed low sensitivity of protozoans to OA is typical for coastal communities where changes in seawater pH occur frequently.

  8. Transfer of radiocaesium from contaminated bottom sediments to marine organisms through benthic food chains in post-Fukushima and post-Chernobyl periods

    Science.gov (United States)

    Bezhenar, Roman; Jung, Kyung Tae; Maderich, Vladimir; Willemsen, Stefan; de With, Govert; Qiao, Fangli

    2016-05-01

    After the earthquake and tsunami on 11 March 2011 damaged the Fukushima Dai-ichi Nuclear Power Plant (FDNPP), an accidental release of a large amount of radioactive isotopes into both the air and the ocean occurred. Measurements provided by the Japanese agencies over the past 5 years show that elevated concentrations of 137Cs still remain in sediments, benthic organisms, and demersal fishes in the coastal zone around the FDNPP. These observations indicate that there are 137Cs transfer pathways from bottom sediments to the marine organisms. To describe the transfer quantitatively, the dynamic food chain biological uptake model of radionuclides (BURN) has been extended to include benthic marine organisms. The extended model takes into account both pelagic and benthic marine organisms grouped into several classes based on their trophic level and type of species: phytoplankton, zooplankton, and fishes (two types: piscivorous and non-piscivorous) for the pelagic food chain; deposit-feeding invertebrates, demersal fishes fed by benthic invertebrates, and bottom omnivorous predators for the benthic food chain; crustaceans, mollusks, and coastal predators feeding on both pelagic and benthic organisms. Bottom invertebrates ingest organic parts of bottom sediments with adsorbed radionuclides which then migrate up through the food chain. All organisms take radionuclides directly from water as well as food. The model was implemented into the compartment model POSEIDON-R and applied to the north-western Pacific for the period of 1945-2010, and then for the period of 2011-2020 to assess the radiological consequences of 137Cs released due to the FDNPP accident. The model simulations for activity concentrations of 137Cs in both pelagic and benthic organisms in the coastal area around the FDNPP agree well with measurements for the period of 2011-2015. The decrease constant in the fitted exponential function of simulated concentration for the deposit-feeding invertebrates (0.45 yr-1

  9. Marine Communities of North Sea Offshore Platforms, and the Use of Stable Isotopes to Explore Artificial Reef Food Webs

    OpenAIRE

    Guerin, Andrew James

    2009-01-01

    Stable isotope methods offer a powerful means of investigating trophic interactions, allowing assessment of the relative importance of multiple nutrient sources to biological assemblages, as well as estimation of the trophic positions of consumers. Differences in the isotope ratios of consumers between habitats can thus indicate differences in the structures of food webs, or the contributions of different food sources to those food webs. Isotope methods were used to compare ...

  10. Trophic transfer and accumulation of TiO2 nanoparticles from clamworm (Perinereis aibuhitensis) to juvenile turbot (Scophthalmus maximus) along a marine benthic food chain.

    Science.gov (United States)

    Wang, Zhenyu; Yin, Liyun; Zhao, Jian; Xing, Baoshan

    2016-05-15

    In the present work, we investigated the potential benthic trophic transfer of TiO2 nanoparticles (NPs) from clamworm (Perinereis aibuhitensis) to juvenile turbot (Scophthalmus maximus) and their related distribution and toxicity. TiO2 NPs (at 10, 50 and 100 mg/L) could be taken up by clamworms, and mainly accumulated in the lower-digestive tract. TiO2 NPs were able to transfer from clamworms to juvenile turbots. The accumulation of TiO2 NPs in juvenile turbots increased with increasing Ti contents in clamworms during the dietary exposure, however, no biomagnification (BMFs, 0.30-0.33) of TiO2 NPs was observed. For both dietary and waterborne exposure, accumulation of TiO2 NPs was higher in the gill, intestine and stomach of juvenile turbot, following by skin, liver, and muscle. During dietary exposure at Day 20, the growth of turbots was reduced, and abnormal symptoms of liver and spleen were detected. Moreover, both dietary (50 and 100 mg/L TiO2 NPs-treated clamworms) and waterborne (100 mg/L TiO2 NPs) exposures led to significantly lower protein and higher lipid contents, suggesting the nutrition quality reduction of turbots. The findings from this work highlighted the trophic transfer of TiO2 NPs in marine benthic food chain, leading to the potential negative impact on marine aquaculture and food quality. PMID:27010785

  11. Non-proportional bioaccumulation of trace metals and metalloids in the planktonic food web of two Singapore coastal marine inlets with contrasting water residence times.

    Science.gov (United States)

    Calbet, Albert; Schmoker, Claire; Russo, Francesca; Trottet, Aurore; Mahjoub, Mohamed-Sofiane; Larsen, Ole; Tong, Hor Yee; Drillet, Guillaume

    2016-08-01

    We analyzed the concentrations of trace metals/metalloids (TMs) in the water, sediment and plankton of two semi-enclosed marine coastal inlets located north of Jurong Island and separated by a causeway (SW Singapore; May 2012-April 2013). The west side of the causeway (west station) has residence times of approximately one year, and the east side of the causeway (east station) has residence times of one month. The concentrations of most of the TMs in water and sediment were higher in the west than in the east station. In the water column, most of the TMs were homogeneously distributed or had higher concentrations at the surface. Preliminary evidence suggests that the TMs are primarily derived from aerosol depositions from oil combustion and industry. Analyses of TMs in seston (>0.7μm; mostly phytoplankton) and zooplankton (>100μm) revealed that the seston from the west station had higher concentrations of most TMs; however, the concentrations of TMs in zooplankton were similar at the two stations. Despite the high levels of TMs in water, sediment and seston, the bioaccumulation detected in zooplankton was moderate, suggesting either the presence of effective detoxification mechanisms or/and the inefficient transfer of TMs from primary producers to higher trophic levels as a result of the complexity of marine planktonic food webs. In summary, the TM concentrations in water and seston are not reliable indicators of the bioaccumulation at higher trophic levels of the food web. PMID:27104581

  12. Priceless prices and marine food webs: Long-term patterns of change and fishing impacts in the South Brazil Bight as reflected by the seafood market

    Science.gov (United States)

    Pincinato, R. B. M.; Gasalla, M. A.

    2010-10-01

    The lack of market variables in fishery systems (i.e., prices and quantities) has often been cited as one reason for the particular difficulty of understanding whole marine ecosystem change and its management under a broader ecosystem perspective. This paper shows the results of efforts to tackle this problem in the South Brazil Bight by compiling and analyzing in-depth an unprecedented 40-year database from the region’s largest wholesale seafood market, based in the megacity of São Paulo. Fishery landings and market values for the period 1968-2007 were analyzed primarily by updated trophic level classes and multispecies indicators including the (1) marine trophic index (MTI), (2) weighted price, and (3) log relative price index (LRPI) which relates prices and trophic levels. Moreover, an inferential analysis of major seafood category statistical trends in market prices and quantities and their positive and negative correlations was undertaken. In general, these market trends contributed substantially to identifying and clarifying the changes that occurred. Considerations of the behavior of demand, supply and markets are included. In particular, while the MTI did not support a “fishing down the marine food web” hypothesis, other indicators did show the continued scarcity of major high trophic level categories and fisheries target species. Overall, the results indicate that the analysis of fishery landings, or of certain other indicators alone, can mask real changes. Rather, a joint ecological-econometric analysis provides better evidence of the direction of ecosystem pressures and stock health. This method for detecting market changes across the food web may be particularly helpful for systems considered data-poor but where fish market data have been archived. This study further elucidates historical changes and fishing impacts in the South Brazil Bight ecosystem.

  13. An Arctic perspective on dating Mid-Late Pleistocene environmental history

    DEFF Research Database (Denmark)

    Alexanderson, Helena; Backman, Jan; Cronin, Thomas M.;

    2014-01-01

    To better understand Pleistocene climatic changes in the Arctic, integrated palaeoenvironmental and palaeoclimatic signals from a variety of marine and terrestrial geological records as well as geochronologic age control are required, not least for correlation to extra-Arctic records. In this pap...

  14. OCEANOGRAPHY & MARINE GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20110729 Bai Youcheng(Laboratory of Marine Ecosystem and Biogeochemistry,SOA,Second Institute of Oceanography,Hangzhou 310012,China);Chen Jianfang Biomarker Records in Sediment Core of R12a from the Chukchi Sea during the Last 500 Years(Acta Sedimentologica Sinica,ISSN1000-0550,CN62-1038/P,28(4),2010,p.768-775,6 illus.,40 refs.)Key words:biomarkers,marine sediments,paleoproductivity,Arctic region This paper used multi-biomarkers to study the R12a core’s top 40 cm samples’ phytoplankton and community sampled during the Second Chinese Arctic expedition from the Chukchi Sea in summer,2003,and to obtain the information of the phytoplankton production and community change since 500 a.The results indicate the total and individual primary productivity increased over the last 500 a.The phytoplankton community structure mostly shows the contributions of

  15. Sea ice in the Canadian Arctic in the 21. century

    International Nuclear Information System (INIS)

    Climate warming will occur first and most intensely in Arctic regions, according to the numerical simulations of future climate performed with different Global Climate Models (GCMs). It includes the simulations performed by the Meteorological Service of Canada. The observations gathered in the Arctic indicate that the present warming has no precedent over the past four hundred years. Since the 1970s, data acquired mainly by satellite indicates that the extent of Arctic sea ice decreased at a rate of approximately three per cent per decade. Over the period 1969-2000, a similar rate of decrease has been observed within Canadian Arctic waters. Over the past forty years, estimates of the thickness of ice in the Arctic, based on submarine measurements, show a 40 per cent decrease. By 2050, if all the conditions remain as they are, the Arctic Ocean could be ice free. The most widely held scientific opinion seems to be that in the future there will be less ice in the Arctic than what was observed in the past, an opinion that is still being debated by scientists. The development of local natural resources and trans-shipment between Europe and Asia could increase dramatically in a future with less ice. Marine transportation in the Canadian Arctic would be expanded. Climatological analysis results of Canadian ice information is presented by the authors, and they have chosen to discuss various probable scenarios related to ice conditions during this century. 13 refs., 8 figs

  16. Expansion of vegetated coastal ecosystems in the future Arctic

    Directory of Open Access Journals (Sweden)

    Dorte eKrause-Jensen

    2014-12-01

    Full Text Available Warming occurs particularly fast in the Arctic and exerts profound effects on arctic ecosystems. Sea ice-associated ecosystems are projected to decline but reduced arctic sea ice cover also increases the solar radiation reaching the coastal seafloors with the potential for expansion of vegetated habitats, i.e. kelp forests and seagrass meadows. These habitats support key ecosystem functions, some of which may mitigate effects of climate change. Therefore, the likely expansion of vegetated coastal habitats in the Arctic will generate new productive ecosystems, offer habitat for a number of invertebrate and vertebrate species, including provision of refugia for calcifiers from possible threats from ocean acidification, contribute to enhance CO2 sequestration and protect the shoreline from erosion. The development of models allowing quantitative forecasts of the future of vegetated arctic ecosystems requires that key hypotheses underlying such forecasts be tested. Here we propose a set of three key testable hypotheses along with a research agenda for testing them using a broad diversity of approaches, including analyses of paleo-records, space for-time substitutions and experimental studies. The research agenda proposed would provide a solid underpinning to guide forecasts on the spread of marine macrophytes onto the Arctic with climate change and contribute to balance our understanding of climate change impacts on the arctic ecosystem through a focus on the role of engineering species. Anticipating these changes in ecosystem structure and function is key to develop managerial strategies to maximize these ecosystem services in a future warmer Arctic.

  17. Moderate-resolution sea surface temperature data for the Arctic Ocean Ecoregions

    Science.gov (United States)

    Sea surface temperature (SST) is an important environmental characteristic in determining the suitability and sustainability of habitats for marine organisms. Of particular interest is the fate of the Arctic Ocean, which provides critical habitat to commercially important fish (M...

  18. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Northwest Arctic, Alaska: INVERT (Invertebrate Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine invertebrate species in Northwest Arctic, Alaska. Vector polygons in this data...

  19. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Northwest Arctic, Alaska: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, freshwater, and anadromous fish species in Northwest Arctic, Alaska. Vector...

  20. Structure and seasonal variability of fish food webs in an estuarine tropical marine protected area (Senegal): Evidence from stable isotope analysis

    Science.gov (United States)

    Faye, Djibril; Tito de Morais, Luis; Raffray, Jean; Sadio, Oumar; Thiaw, Omar Thiom; Le Loc'h, François

    2011-05-01

    West African tropical estuaries play an important role in the growth and survival of many commercially exploited fish species and enable the sustainability of considerable artisanal fishery yields. However, their trophic functioning remains poorly understood. In the Sine Saloum estuary (Senegal), a marine protected area (MPAs) was designated in 2003 to manage fisheries resources. The present study aimed to determine the structure, trophic functioning and seasonal patterns of the fish assemblages in this MPA. Throughout the study, 28 fish species were collected, with higher values of biomass (3826 kg km -2) recorded during the wet season and lower values during the dry season (1228 kg km -2). Fish assemblages in both seasons were dominated by species with marine affinity, which accounted for 87% of the total biomass in the wet season and 70% in the dry season, with their abundance varying from 83% to 57%, respectively. Based on stable isotopic composition (δ 13C and δ 15N), species were combined into trophic groups. Primary consumers were partitioned into suspensivores (pelagic copepods, oysters and mussels), which fed mainly on particulate organic matter, and intermediate consumers, feeding on freshly deposited organic matter and benthic microalgae ( Sarotherodon melanotheron and Arca senilis). Secondary consumers were divided into three groups. The first group included mullet, which fed by grazing on benthic microalgae (benthic affinity feeders). The second group, pelagic affinity feeders, was the most heterogeneous and fed mainly on pelagic components. The last secondary consumer group termed the intermediate group, included piscivores and benthic and pelagic invertebrate feeders, which dominated the top of the food web. The food chain in October was lengthened due to the occurrence of tertiary consumers. Food webs were dominated by secondary consumers, which constituted 89% of total biomass in the dry season and 71% in the wet season. The fish food web varied

  1. Literature review of available techniques to characterize marine and estuarine food webs; with emphasis for application in the model OMEGA

    NARCIS (Netherlands)

    Lange, de H.J.; Brink, van den N.W.

    2006-01-01

    Food webs can be characterized by use of markers. These are increasingly used in food web studies since they are the only tool that can be used to infer relations through multiple trophic levels. Such a marker is a characteristic of an organism that can be objectively measured and evaluated as an in

  2. A Comparative Study of the Influence of Energy Level in the Fillet and Food Intake of Economically Important Marine-and-Freshwater Fish Species from Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Mohd. Javed Kamal Shamsi

    2014-11-01

    Full Text Available Energy content interms of calories/ gram dry weight in the fillet as well as in the food as the dietary ratio of some economically important fishes from different habitat (Marine and freshwater were determined by two methods; The Organic Carbon and The Karzinkin Tarkovaskaya. The energy value of the nutrients in the fillet/food was determined by these two methods which were highly significant (p<0.001 and in order [Rastrillegar kanagurta(988.50/8251.66 and 12088.28/8694.46 Joules gm-1; Lethrinus lentjan (7274.80/ 5544.50 and 9237.30/ 5978.26 Joules gm-1; Aphareus rutilans (6891.56/ 4813.56 and 9092 58/ 5136.78 Joules gm-1 and Chanos chanos (6681.50/ 5120.56 and 8841.48/ 5520.54 Joules gm-1] in Marine water fishes. As compare to other environment of freshwater, the order was as such, Clarius gariepinus (7888.61/6613.83 and 8779.25/7290.40 Joules gm-1 Oreochromis niloticus (6103.00/4778.69 and 6896.20/5584.16 Joules gm-1; Cyprinus carpio (5639.38/4276.49 and 6370.41/4942.18 Joules gm-1 and Gara tibanica (4353. 22/3300.45 and 3882.73/2680.53 Joules gm-1 respectively. The moisture content and the ratio of energetic values of fillet/food were also determined and tabulated. Consistency of the results obtained indicate the reliability of the method used and to explain the validity of conversion factor from weight to energy which will be useful for general estimation of energy contents and energy flow in aquatic ecosystem.

  3. Pan-Arctic observations in GRENE Arctic Climate Change Research Project and its successor

    Science.gov (United States)

    Yamanouchi, Takashi

    2016-04-01

    We started a Japanese initiative - "Arctic Climate Change Research Project" - within the framework of the Green Network of Excellence (GRENE) Program, funded by the Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT), in 2011. This Project targeted understanding and forecasting "Rapid Change of the Arctic Climate System and its Global Influences." Four strategic research targets are set by the Ministry: 1. Understanding the mechanism of warming amplification in the Arctic; 2. Understanding the Arctic climate system for global climate and future change; 3. Evaluation of the impacts of Arctic change on the weather and climate in Japan, marine ecosystems and fisheries; 4. Projection of sea ice distribution and Arctic sea routes. Through a network of universities and institutions in Japan, this 5-year Project involves more than 300 scientists from 39 institutions and universities. The National Institute of Polar Research (NIPR) works as the core institute and The Japan Agency for Marine- Earth Science and Technology (JAMSTEC) joins as the supporting institute. There are 7 bottom up research themes approved: the atmosphere, terrestrial ecosystems, cryosphere, greenhouse gases, marine ecology and fisheries, sea ice and Arctic sea routes and climate modeling, among 22 applications. The Project will realize multi-disciplinal study of the Arctic region and connect to the projection of future Arctic and global climatic change by modeling. The project has been running since the beginning of 2011 and in those 5 years pan-Arctic observations have been carried out in many locations, such as Svalbard, Russian Siberia, Alaska, Canada, Greenland and the Arctic Ocean. In particular, 95 GHz cloud profiling radar in high precision was established at Ny-Ålesund, Svalbard, and intensive atmospheric observations were carried out in 2014 and 2015. In addition, the Arctic Ocean cruises by R/V "Mirai" (belonging to JAMSTEC) and other icebreakers belonging to other

  4. The role of docosahexaenoic and the marine food web as determinants of evolution and hominid brain development: the challenge for human sustainability.

    Science.gov (United States)

    Crawford, Michael A; Broadhurst, C Leigh

    2012-01-01

    Life originated on this planet about 3 billion years ago. For the first 2.5 billion years of life there was ample opportunity for DNA modification. Yet there is no evidence of significant change in life forms during that time. It was not until about 600 million years ago, when the oxygen tension rose to a point where air-breathing life forms became thermodynamically possible, that a major change can be abruptly seen in the fossil record. The sudden appearance of the 32 phyla in the Cambrian fossil record was also associated with the appearance of intracellular detail not seen in previous life forms. That detail was provided by cell membranes made with lipids (membrane fats) as structural essentials. Lipids thus played a major, as yet unrecognised, role as determinants in evolution. The compartmentalisation of intracellular, specialist functions as in the nucleus, mitochondria, reticulo-endothelial system and plasma membrane led to cellular specialisation and then speciation. Thus, not only oxygen but also the marine lipids were drivers in the Cambrian explosion. Docosahexaenoic acid (DHA) (all-cis-docosa-4,7,10,13,16,19-hexaenoic acid, C22:6ω3 or C22:6, n-3, DHA) is a major feature of marine lipids. It requires six oxygen atoms to insert its six double bonds, so it would not have been abundant before oxidative metabolism became plentiful. DHA provided the membrane backbone for the emergence of new photoreceptors that converted photons into electricity, laying the foundation for the evolution of other signalling systems, the nervous system and the brain. Hence, the ω3 DHA from the marine food web must have played a critical role in human evolution. There is also clear evidence from molecular biology that DHA is a determinant of neuronal migration, neurogenesis and the expression of several genes involved in brain growth and function. That same process was essential to the ultimate cerebral expansion in human evolution. There is now incontrovertible support of this

  5. The role of docosahexaenoic and the marine food web as determinants of evolution and hominid brain development: the challenge for human sustainability.

    Science.gov (United States)

    Crawford, Michael A; Broadhurst, C Leigh

    2012-01-01

    Life originated on this planet about 3 billion years ago. For the first 2.5 billion years of life there was ample opportunity for DNA modification. Yet there is no evidence of significant change in life forms during that time. It was not until about 600 million years ago, when the oxygen tension rose to a point where air-breathing life forms became thermodynamically possible, that a major change can be abruptly seen in the fossil record. The sudden appearance of the 32 phyla in the Cambrian fossil record was also associated with the appearance of intracellular detail not seen in previous life forms. That detail was provided by cell membranes made with lipids (membrane fats) as structural essentials. Lipids thus played a major, as yet unrecognised, role as determinants in evolution. The compartmentalisation of intracellular, specialist functions as in the nucleus, mitochondria, reticulo-endothelial system and plasma membrane led to cellular specialisation and then speciation. Thus, not only oxygen but also the marine lipids were drivers in the Cambrian explosion. Docosahexaenoic acid (DHA) (all-cis-docosa-4,7,10,13,16,19-hexaenoic acid, C22:6ω3 or C22:6, n-3, DHA) is a major feature of marine lipids. It requires six oxygen atoms to insert its six double bonds, so it would not have been abundant before oxidative metabolism became plentiful. DHA provided the membrane backbone for the emergence of new photoreceptors that converted photons into electricity, laying the foundation for the evolution of other signalling systems, the nervous system and the brain. Hence, the ω3 DHA from the marine food web must have played a critical role in human evolution. There is also clear evidence from molecular biology that DHA is a determinant of neuronal migration, neurogenesis and the expression of several genes involved in brain growth and function. That same process was essential to the ultimate cerebral expansion in human evolution. There is now incontrovertible support of this

  6. Elevated levels of ingested plastic in a high Arctic seabird, the northern fulmar (Fulmarus glacialis)

    OpenAIRE

    Trevail, A.M.; Gabrielsen, G.W.; Kuhn, S.; Franeker, van, J.A.

    2015-01-01

    Plastic pollution is of worldwide concern; however, increases in international commercial activity in the Arctic are occurring without the knowledge of the existing threat posed to the local marine environment by plastic litter. Here, we quantify plastic ingestion by northern fulmars, Fulmarus glacialis, from Svalbard, at the gateway to future shipping routes in the high Arctic. Plastic ingestion by Svalbard fulmars does not follow the established decreasing trend away from human marine impac...

  7. Verrucomicrobia Are Candidates for Polysaccharide-Degrading Bacterioplankton in an Arctic Fjord of Svalbard

    OpenAIRE

    Cardman, Z.; C. Arnosti; Durbin, A.; Ziervogel, K.; Cox, C; A. D. Steen; Teske, A

    2014-01-01

    In Arctic marine bacterial communities, members of the phylum Verrucomicrobia are consistently detected, although not typically abundant, in 16S rRNA gene clone libraries and pyrotag surveys of the marine water column and in sediments. In an Arctic fjord (Smeerenburgfjord) of Svalbard, members of the Verrucomicrobia, together with Flavobacteria and smaller proportions of Alpha- and Gammaproteobacteria, constituted the most frequently detected bacterioplankton community members in 16S rRNA gen...

  8. Anadromous char as an alternate food choice to marine animals: a synthesis of Hg concentrations, population features and other influencing factors.

    Science.gov (United States)

    Evans, Marlene S; Muir, Derek C G; Keating, Jonathan; Wang, Xiaowa

    2015-03-15

    This study was conducted to confirm sporadic measurements made over the late 1970s to the early 1990 s which determined that mercury (Hg) concentrations were low in anadromous char across Arctic and subarctic Canada including northern Québec and Labrador. Over 2004-2013, anadromous char populations across northern Canada were investigated at 20 sites for Hg concentrations and life history characteristics. Hg concentrations were extremely low in anadromous char muscle, typically factor and %lipid; correlations with carbon isotope (δ(13)C) ratio were inconsistent. Location and year were significant variables influencing Hg concentrations over the study area; longitude and latitude also were significant influencing variables. Char length, weight, age, condition factor and lipid content explained additional variance. A tendency towards higher Hg concentrations with increasing latitude may be partially related to decreasing growth of char towards the north. However, Hg concentrations in char were positively correlated with growth rates suggesting that Hg concentrations in char also were higher in the more productive study areas, including to the west where mainland riverine inputs of terrestrial carbon, nutrients, and Hg were greater. The data base for assessing time trends in char was limited by the small number of years investigated at most locations, variable fish size across years, small sample size, etc. Where temporal trends were detected, they were of increase on the long term (1970s, 1980s or early 1990 s to the present) but of decrease on the short term (early 2000s to present) with Nain (Labrador) showing the converse pattern. Higher Hg concentrations were also related to lower condition factor and cooler springs. Hg concentrations in anadromous char are compared with other terrestrial, aquatic and marine vertebrates in traditional diets. The known information on anadromous char is reviewed including population features, habitat, and harvests. Future Hg

  9. Current status on marine litter indicators in Nordic waters

    DEFF Research Database (Denmark)

    Strand, Jakob; Tairova, Zhanna; Magnusson, Kerstin;

    Status for project on Marine litter in the Nordic waters. This includes a review of Nordic studies on marine litter indicators. Various studies as part of either research or existing monitoring have provided information on occurrence of marine litter in Nordic waters from Baltic Sea to the Arctic....

  10. Marine Picoeukaryotes in Cold Water

    DEFF Research Database (Denmark)

    Sørensen, Nikolaj

    Picoeukaryotes form an important part of marine ecosystems, both as primary producers, bacterial grazers and parasites. The Arctic is experiencing accelerated global warming and picoeukaryotes may thus be considered to be at the forefront of climate change. This PhD thesis sets out to investigate...

  11. Diet composition and food habits of demersal and pelagic marine fishes from Terengganu waters, east coast of Peninsular Malaysia

    OpenAIRE

    Bachok, Z.; Mansor, M.I.; Noordin, R. M.

    2004-01-01

    Fish stomachs from 18 demersal and pelagic fishes from the coast of Terengganu in Malaysia were examined. The components of the fishesÆ diets varied in number, weight, and their frequency of occurrence. The major food items in the stomachs of each species were determined using an Index of Relative Importance. A "conceptualö food web structure indicates that fish species in the study area can be classified into three predatory groups: (1) predators on largely planktivorous or pelagic species; ...

  12. Literature review of available techniques to characterize marine and estuarine food webs; with emphasis for application in the model OMEGA

    OpenAIRE

    Lange, de, E.C.M.; Brink, van den, R.B.A.

    2006-01-01

    Food webs can be characterized by use of markers. These are increasingly used in food web studies since they are the only tool that can be used to infer relations through multiple trophic levels. Such a marker is a characteristic of an organism that can be objectively measured and evaluated as an indicator of normal biologic processes. These include fatty acids, stable isotopes, and molecular markers such as immunological markers and DNA markers. This report presents the results of a literatu...

  13. Arctic Climate Tipping Points

    OpenAIRE

    Lenton, Timothy M.

    2012-01-01

    There is widespread concern that anthropogenic global warming will trigger Arctic climate tipping points. The Arctic has a long history of natural, abrupt climate changes, which together with current observations and model projections, can help us to identify which parts of the Arctic climate system might pass future tipping points. Here the climate tipping points are defined, noting that not all of them involve bifurcations leading to irreversible change. Past abrupt climate changes in the A...

  14. Mapping the future expansion of Arctic open water

    Science.gov (United States)

    Barnhart, Katherine R.; Miller, Christopher R.; Overeem, Irina; Kay, Jennifer E.

    2016-03-01

    Sea ice impacts most of the Arctic environment, from ocean circulation and marine ecosystems to animal migration and marine transportation. Sea ice has thinned and decreased in age over the observational record. Ice extent has decreased. Reduced ice cover has warmed the surface ocean, accelerated coastal erosion and impacted biological productivity. Declines in Arctic sea-ice extent cannot be explained by internal climate variability alone and can be attributed to anthropogenic effects. However, extent is a poor measure of ice decline at specific locations as it integrates over the entire Arctic basin and thus contains no spatial information. The open water season, in contrast, is a metric that represents the duration of open water over a year at an individual location. Here we present maps of the open water season over the period 1920-2100 using daily output from a 30-member initial-condition ensemble of business-as-usual climate simulations that characterize the expansion of Arctic open water, determine when the open water season will move away from pre-industrial conditions (`shift’ time) and identify when human forcing will take the Arctic sea-ice system outside its normal bounds (`emergence’ time). The majority of the Arctic nearshore regions began shifting in 1990 and will begin leaving the range of internal variability in 2040. Models suggest that ice will cover coastal regions for only half of the year by 2070.

  15. Arctic wind energy

    Energy Technology Data Exchange (ETDEWEB)

    Peltola, E. [Kemijoki Oy (Finland); Holttinen, H.; Marjaniemi, M. [VTT Energy, Espoo (Finland); Tammelin, B. [Finnish Meteorological Institute, Helsinki (Finland)

    1998-12-31

    Arctic wind energy research was aimed at adapting existing wind technologies to suit the arctic climatic conditions in Lapland. Project research work included meteorological measurements, instrument development, development of a blade heating system for wind turbines, load measurements and modelling of ice induced loads on wind turbines, together with the development of operation and maintenance practices in arctic conditions. As a result the basis now exists for technically feasible and economically viable wind energy production in Lapland. New and marketable products, such as blade heating systems for wind turbines and meteorological sensors for arctic conditions, with substantial export potential, have also been developed. (orig.)

  16. Calcareous microfossil-based orbital cyclostratigraphy in the Arctic Ocean

    Science.gov (United States)

    Marzen, Rachel E.; DeNinno, Lauren H.; Cronin, Thomas M.

    2016-10-01

    Microfaunal and geochemical proxies from marine sediment records from central Arctic Ocean (CAO) submarine ridges suggest a close relationship over the last 550 thousand years (kyr) between orbital-scale climatic oscillations, sea-ice cover, marine biological productivity and other parameters. Multiple paleoclimate proxies record glacial to interglacial cycles. To understand the climate-cryosphere-productivity relationship, we examined the cyclostratigraphy of calcareous microfossils and constructed a composite Arctic Paleoclimate Index (API) "stack" from benthic foraminiferal and ostracode density from 14 sediment cores. Following the hypothesis that API is driven mainly by changes in sea-ice related productivity, the API stack shows the Arctic experienced a series of highly productive interglacials and interstadials every ∼20 kyr. These periods signify minimal ice shelf and sea-ice cover and maximum marine productivity. Rapid transitions in productivity are seen during shifts from interglacial to glacial climate states. Discrepancies between the Arctic API curves and various global climatic, sea-level and ice-volume curves suggest abrupt growth and decay of Arctic ice shelves related to climatic and sea level oscillations.

  17. HAUSGARTEN: Multidisciplinary investigations at a deep-sea, long-term observatory in the Arctic Ocean

    OpenAIRE

    Soltwedel, T.; Bauerfeind, E.; Bergmann, M.; Budaeva, N.; Hoste, E; Jaeckisch, N.; von Juterzenka, K.; Matthiessen, J.; Mokievsky, V.; Nöthig, E.-M.; Quéric, N.-V.; Sablotny, B.; Sauter, E.; Schewe, I.; Urban-Malinga, B.

    2005-01-01

    The marine Arctic has played an essential role in the history of our planet over the past 130 million years and contributes considerably to the present functioning of Earth and its life. The global cycles of a variety of materials fundamental to atmospheric conditions and thus to life depend to a signifi cant extent on Arctic marine processes (Aargaard et al., 1999). The past decades have seen remarkable changes in key Arctic variables. The decrease of sea-ice extent and sea-ice thickness in ...

  18. Radiocaesium turnover in Arctic charr (Salvelinus alpinus) and brown trout (Salmo trutta) in a Norwegian lake

    International Nuclear Information System (INIS)

    The radioactivity of brown trout (Salmo trutta L.) and Arctic charr (Salvelinus alpinus (L.)) was monitored in a Norwegian lake from 1986 to 1989. A distinct difference was observed between brown trout and Arctic charr in the accumulation of radiocaesium (134Cs and 137Cs) from the Chernobyl fallout, and the study focused on the understanding of this difference. Brown trout had a large food consumption and a corresponding high intake of radiocaesium. Excretion was 20% faster in brown trout than Arctic charr as brown trout lived at high temperatures in epilimnic water. Arctic charr had a lower food consumption (less than one-third of trout) and lived in colder meta-and hypolimnic water. Arctic charr therefore had a lower intake and slower excretion of radiocaesium. Brown trout an Arctic charr had different diets. For brown trout zoobenthos was the dominant food item, whereas Artic charr mainly fed on zooplankton. The radioactivity in the stomach contents of the two species was different in 1986, but similar for the rest of the period. Higher levels of radiocaesium in brown trout than Arctic charr in 1986 were due to a higher food consumption and more radioactive food items in its diet. The parallel development in accumulated radiocaesium through summer 1987 was probably formed by brown trout balancing a higher intake with a faster excretion. The ecological half-lives of radiocaesium in brown trout (357 days) and Arctic charr (550 days) from Lake Hoeysjoeen indicated a slow removal of the isotopes from the food webs. (author)

  19. Arctic-COLORS (Coastal Land Ocean Interactions in the Arctic) - a NASA field campaign scoping study to examine land-ocean interactions in the Arctic

    Science.gov (United States)

    Hernes, P.; Tzortziou, M.; Salisbury, J.; Mannino, A.; Matrai, P.; Friedrichs, M. A.; Del Castillo, C. E.

    2014-12-01

    The Arctic region is warming faster than anywhere else on the planet, triggering rapid social and economic changes and impacting both terrestrial and marine ecosystems. Yet our understanding of critical processes and interactions along the Arctic land-ocean interface is limited. Arctic-COLORS is a Field Campaign Scoping Study funded by NASA's Ocean Biology and Biogeochemistry Program that aims to improve understanding and prediction of land-ocean interactions in a rapidly changing Arctic coastal zone, and assess vulnerability, response, feedbacks and resilience of coastal ecosystems, communities and natural resources to current and future pressures. Specific science objectives include: - Quantify lateral fluxes to the arctic inner shelf from (i) rivers and (ii) the outer shelf/basin that affect biology, biodiversity, biogeochemistry (i.e. organic matter, nutrients, suspended sediment), and the processing rates of these constituents in coastal waters. - Evaluate the impact of the thawing of Arctic permafrost within the river basins on coastal biology, biodiversity and biogeochemistry, including various rates of community production and the role these may play in the health of regional economies. - Assess the impact of changing Arctic landfast ice and coastal sea ice dynamics. - Establish a baseline for comparison to future change, and use state-of-the-art models to assess impacts of environmental change on coastal biology, biodiversity and biogeochemistry. A key component of Arctic-COLORS will be the integration of satellite and field observations with coupled physical-biogeochemical models for predicting impacts of future pressures on Arctic, coastal ocean, biological processes and biogeochemical cycles. Through interagency and international collaborations, and through the organization of dedicated workshops, town hall meetings and presentations at international conferences, the scoping study engages the broader scientific community and invites participation of

  20. 2nd International Arctic Ungulate Conference

    Directory of Open Access Journals (Sweden)

    A. Anonymous

    1996-01-01

    Full Text Available The 2nd International Arctic Ungulate Conference was held 13-17 August 1995 on the University of Alaska Fairbanks campus. The Institute of Arctic Biology and the Alaska Cooperative Fish and Wildlife Research Unit were responsible for organizing the conference with assistance from biologists with state and federal agencies and commercial organizations. David R. Klein was chair of the conference organizing committee. Over 200 people attended the conference, coming from 10 different countries. The United States, Canada, and Norway had the largest representation. The conference included invited lectures; panel discussions, and about 125 contributed papers. There were five technical sessions on Physiology and Body Condition; Habitat Relationships; Population Dynamics and Management; Behavior, Genetics and Evolution; and Reindeer and Muskox Husbandry. Three panel sessions discussed Comparative caribou management strategies; Management of introduced, reestablished, and expanding muskox populations; and Health risks in translocation of arctic ungulates. Invited lectures focused on the physiology and population dynamics of arctic ungulates; contaminants in food chains of arctic ungulates and lessons learned from the Chernobyl accident; and ecosystem level relationships of the Porcupine Caribou Herd.

  1. Role of essential lipids in copepod nutrition: no evidence for trophic upgrading of food quality by a marine ciliate

    DEFF Research Database (Denmark)

    Klein Breteler, W.; Koski, Marja; Rampen, S.

    2004-01-01

    -quality Rhodomonas sp. diet. The specific mass of fatty acids in S. sulcatum was much lower than in the Dunaliella sp. diet, However, the fatty acid composition of the protozoan more or less resembled that of the food, lacking long-chain highly unsaturated fatty acids (HUFAs). Sterols only occurred in Dunaliella sp......., although in low abundance of unuseful Delta7 sterols. Obviously, S. sulcatum did not biochemically enhance bacterial or algal food for subsequent use at higher trophic levels, and only transferred fatty acids without further conversion. The results indicate a deficiency in the ciliate of HUFAs and sterols...

  2. White Arctic vs. Blue Arctic: Making Choices

    Science.gov (United States)

    Pfirman, S. L.; Newton, R.; Schlosser, P.; Pomerance, R.; Tremblay, B.; Murray, M. S.; Gerrard, M.

    2015-12-01

    As the Arctic warms and shifts from icy white to watery blue and resource-rich, tension is arising between the desire to restore and sustain an ice-covered Arctic and stakeholder communities that hope to benefit from an open Arctic Ocean. If emissions of greenhouse gases to the atmosphere continue on their present trend, most of the summer sea ice cover is projected to be gone by mid-century, i.e., by the time that few if any interventions could be in place to restore it. There are many local as well as global reasons for ice restoration, including for example, preserving the Arctic's reflectivity, sustaining critical habitat, and maintaining cultural traditions. However, due to challenges in implementing interventions, it may take decades before summer sea ice would begin to return. This means that future generations would be faced with bringing sea ice back into regions where they have not experienced it before. While there is likely to be interest in taking action to restore ice for the local, regional, and global services it provides, there is also interest in the economic advancement that open access brings. Dealing with these emerging issues and new combinations of stakeholders needs new approaches - yet environmental change in the Arctic is proceeding quickly and will force the issues sooner rather than later. In this contribution we examine challenges, opportunities, and responsibilities related to exploring options for restoring Arctic sea ice and potential pathways for their implementation. Negotiating responses involves international strategic considerations including security and governance, meaning that along with local communities, state decision-makers, and commercial interests, national governments will have to play central roles. While these issues are currently playing out in the Arctic, similar tensions are also emerging in other regions.

  3. Episodic fresh surface waters in the Eocene Arctic Ocean

    Science.gov (United States)

    Brinkhuis, Henk; Schouten, Stefan; Collinson, Margaret E.; Sluijs, Appy; Damsté, Jaap S. Sinninghe; Dickens, Gerald R.; Huber, Matthew; Cronin, Thomas M.; Onodera, Jonaotaro; Takahashi, Kozo; Bujak, Jonathan P.; Stein, Ruediger; van der Burgh, Johan; Eldrett, James S.; Harding, Ian C.; Lotter, André F.; Sangiorgi, Francesca; Cittert, Han Van Konijnenburg-Van; de Leeuw, Jan W.; Matthiessen, Jens; Backman, Jan; Moran, Kathryn; Expedition 302 Scientists

    2006-06-01

    It has been suggested, on the basis of modern hydrology and fully coupled palaeoclimate simulations, that the warm greenhouse conditions that characterized the early Palaeogene period (55-45Myr ago) probably induced an intensified hydrological cycle with precipitation exceeding evaporation at high latitudes. Little field evidence, however, has been available to constrain oceanic conditions in the Arctic during this period. Here we analyse Palaeogene sediments obtained during the Arctic Coring Expedition, showing that large quantities of the free-floating fern Azolla grew and reproduced in the Arctic Ocean by the onset of the middle Eocene epoch (~50Myr ago). The Azolla and accompanying abundant freshwater organic and siliceous microfossils indicate an episodic freshening of Arctic surface waters during an ~800,000-year interval. The abundant remains of Azolla that characterize basal middle Eocene marine deposits of all Nordic seas probably represent transported assemblages resulting from freshwater spills from the Arctic Ocean that reached as far south as the North Sea. The termination of the Azolla phase in the Arctic coincides with a local sea surface temperature rise from ~10°C to 13°C, pointing to simultaneous increases in salt and heat supply owing to the influx of waters from adjacent oceans. We suggest that onset and termination of the Azolla phase depended on the degree of oceanic exchange between Arctic Ocean and adjacent seas.

  4. Functional biology and ecological role of krill in Northern marine ecosystems

    DEFF Research Database (Denmark)

    Agersted, Mette Dalgaard

    ) and by production of fast sinking carbon-rich faecal pellets. Hence, the large schools of krill greatly influence the pelagic food web and the flux of organic matter in the sea. However, knowledge of the distribution and feeding biology in krill from northern areas is scarce, although of importance to get a better......Krill is an understudied key group of zooplankton, which transfers energy through the food web by linking lower and higher trophic levels. Furthermore, krill play an important role in the biological pump by transporting carbon out of the euphotic zone to depth by diel vertical migration (DVM...... understanding of the marine ecosystems and food webs. This thesis aimed to gain more knowledge of krill in northern hemisphere and to study their trophic position and grazing impact in a sub-Arctic fjord. The project investigated i) species and population composition of krill in the area of Godthåbsfjord, SW...

  5. Notes on the Holocene marine fauna of eastern North Greenland

    DEFF Research Database (Denmark)

    Bennike, Ole; Funder, Svend Visby; Hjorth, Christian

    1986-01-01

    A list of invertebrates, notably molluscs, from the raised Holocene marine sedimets in eastern North Greenland is given. The faunas have low diversity, and contain an element of Arctic sublittoral and bathyal species indicative of cold surface water.......A list of invertebrates, notably molluscs, from the raised Holocene marine sedimets in eastern North Greenland is given. The faunas have low diversity, and contain an element of Arctic sublittoral and bathyal species indicative of cold surface water....

  6. Trophodynamics of current use pesticides and ecological relationships in the Bathurst region vegetation-caribou-wolf food chain of the Canadian Arctic.

    Science.gov (United States)

    Morris, Adam D; Muir, Derek C G; Solomon, Keith R; Teixeira, Camilla; Duric, Mark; Wang, Xiaowa

    2014-09-01

    The bioaccumulation of current use pesticides (CUPs) and stable isotopes of carbon and nitrogen were investigated in vegetation-caribou-wolf food chain in the Bathurst region (Nunavut, Canada). Volumetric bioconcentration factors (BCF(v)) in vegetation were generally greatest for dacthal (10-12) ≥ endosulfan sulfate (10-11) > ß-endosulfan (>9.0-9.7) ≥ pentachloronitrobenzene (PCNB; 8.4-9.6) > α-endosulfan (8.3-9.3) > chlorpyrifos (8.0-8.7) >chlorothalonil (7.6-8.3). The BCF(v) values in vegetation were significantly correlated with the logarithm of the octanol-air partition coefficients (log K(OA)) of CUPs (r(2)  = 0.90, p = 0.0040), although dacthal was an outlier and not included in this relationship. Most biomagnification factors (BMFs) for CUPs in caribou:diet comparisons were significantly less than 1. Similarly, the majority of wolf:caribou BMFs were either significantly less than 1 or were not statistically greater than 1. Significant trophic magnification factors (TMFs) were all less than 1, indicating that these CUPs exhibit trophic dilution through this terrestrial food chain. The log K(OA) reasonably predicted bioconcentration in vegetation for most CUPs but was not correlated with BMFs or TMFs in mammals. Our results, along with those of metabolic studies, suggest that mammals actively metabolize these CUPs, limiting their biomagnification potential despite entry into the food chain through effective bioconcentration in vegetation.

  7. Arctic Sea Level Reconstruction

    DEFF Research Database (Denmark)

    Svendsen, Peter Limkilde

    method.For oceanographic purposes, the altimetric record over the Arctic Ocean is inferiorin quality to that of moderate latitudes, but nonetheless an invaluable set of observations. During this project, newly processed Arctic altimetry from the ERS-1/-2 and Envisat missions has become available......Reconstruction of historical Arctic sea level is very difficult due to the limited coverage and quality of tide gauge and altimetry data in the area. This thesis addresses many of these issues, and discusses strategies to help achieve a stable and plausible reconstruction of Arctic sea level from...... 1950 to today.The primary record of historical sea level, on the order of several decades to a few centuries, is tide gauges. Tide gauge records from around the world are collected in the Permanent Service for Mean Sea Level (PSMSL) database, and includes data along the Arctic coasts. A reasonable...

  8. Ice-Free Arctic Ocean?

    Science.gov (United States)

    Science Teacher, 2005

    2005-01-01

    The current warming trends in the Arctic may shove the Arctic system into a seasonally ice-free state not seen for more than one million years, according to a new report. The melting is accelerating, and researchers were unable to identify any natural processes that might slow the deicing of the Arctic. "What really makes the Arctic different from…

  9. Mercury and selenium in seston, marine plankton and fish (Sardinella brasiliensis) as a tool for understanding a tropical food web.

    Science.gov (United States)

    Seixas, Tércia Guedes; Moreira, Isabel; Kehrig, Helena Amaral

    2015-12-15

    Mercury (Hg) and selenium (Se) concentrations were evaluated in a planktivorous fish and four size classes of organisms (FSCO), collected at an oligotrophic bay in the Southeastern Brazilian coast. No significant spatial differences between Hg and Se were found in the FSCO within the five sampling points in the bay. Hg and Se concentrations increased with successive increases in the size class of the analyzed plankton, i.e. approximately 3-and 2-fold, respectively, from microplankton to macroplankton. Hg and Se biomagnified throughout the planktonic food web. The smallest size class of organism, seston, composed of both biotic and abiotic portions, and fish showed the highest Hg concentrations. This indicates that Hg is not biomagnifying in the base of the bay food web. Selenium concentrations in fish were approximately 5.9 times higher than those in seston. Hg and Se concentrations in fish were approximately 3.5 and 14.6 times higher than those found in the plankton, respectively.

  10. Tracking and responding to a changing Arctic sea-ice cover: How ice users can help the scientific community design better observing systems (Louis Agassiz Medal Lecture)

    Science.gov (United States)

    Eicken, Hajo

    2010-05-01

    The Arctic sea-ice cover is undergoing a major transformation, with substantial reductions in summer ice extent reflecting changes in ice thickness, age, and circulation. These changes are impacting Arctic ecosystems and a range of human activities. Anticipating and responding to such impacts, exacerbated by increasing economic activity in parts of the Arctic, requires a foundation of environmental observations and model predictions. Recent increases in industrial activities such as shipping and resource development in parts of the Arctic have further highlighted the need for an integrated observing system. In the case of a changing sea-ice cover, how would one best design and optimize such a system? One of the challenges is to meet the information needs of the scientific community in furthering fundamental understanding of the Arctic system, as well as those of key stakeholders and society, helping them to prepare for and respond to Arctic change. This presentation focuses on how the concept of sea-ice system services, i.e., the uses and benefits (or harm) derived from sea ice, may help guide the implementation of an effective observing system. Principal service categories are (1) sea ice as climate regulator, marine hazard, and coastal buffer; (2) transportation and use of ice as a platform; (3) cultural services obtained from the "icescape"; and (4) support of food webs and biological diversity by sea ice. An analysis of the different ice services provided to different user groups can help prioritize different types of observations and determine optimal measurement strategies. Moreover, the focus on different uses of the ice cover may also help synthesize fundamental and applied research to help Arctic communities adapt in a changing environment. Alaska has experienced some of the most substantial changes in sea-ice conditions throughout the Arctic over the past three decades and is used to illustrate the concepts discussed above. Specifically, we have examined

  11. 77 FR 2513 - Draft Environmental Impact Statement for Effects of Oil and Gas Activities in the Arctic Ocean

    Science.gov (United States)

    2012-01-18

    ... Effects of Oil and Gas Activities in the Arctic Ocean AGENCY: National Marine Fisheries Service (NMFS... the Effects of Oil and Gas Activities in the Arctic Ocean.'' Based on several written requests... the Notice of Availability (76 FR 82275, December 30, 2011). Public Meetings Comments will be...

  12. Validation of an Eulerian population model for the marine copepod Calanus finmarchicus in the Norwegian Sea

    Science.gov (United States)

    Alver, Morten Omholt; Broch, Ole Jacob; Melle, Webjørn; Bagøien, Espen; Slagstad, Dag

    2016-08-01

    Calanus finmarchicus is an important zooplankton species in the Norwegian Sea, as a dominant food organism for pelagic fish larvae, and a potentially large source of marine lipids and proteins. Its position in the marine food web also makes it an important model species in assessing the risk posed by oil spills in the Norwegian and Arctic Seas. In this study, an Eulerian population model for C.finmarchicus, coupled to the physical and ecological model SINMOD, is presented. The model includes the full life cycle of C. finmarchicus with a representation of all developmental stages. The model has been validated against field measurements made in different areas of the Norwegian Sea in 1997 and 1998. The model displays geographical and temporal distributions of development stages that is in line with observed patterns. When comparing time series for selected regions, we see a high degree of variability both in the field samples and model output. On average, the model deviations are near half of the summed variability of the field data and model estimates. The model has applications within assessment of ecological production, and the potential for harvesting in the Norwegian and Arctic Seas, but in combination with other models, also for the assessment of ecological effects of oil spills and other types of pollution.

  13. Arctic Climate Systems Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ivey, Mark D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Robinson, David G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Boslough, Mark B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Backus, George A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Peterson, Kara J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); van Bloemen Waanders, Bart G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Swiler, Laura Painton [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Desilets, Darin Maurice [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Reinert, Rhonda Karen [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-03-01

    This study began with a challenge from program area managers at Sandia National Laboratories to technical staff in the energy, climate, and infrastructure security areas: apply a systems-level perspective to existing science and technology program areas in order to determine technology gaps, identify new technical capabilities at Sandia that could be applied to these areas, and identify opportunities for innovation. The Arctic was selected as one of these areas for systems level analyses, and this report documents the results. In this study, an emphasis was placed on the arctic atmosphere since Sandia has been active in atmospheric research in the Arctic since 1997. This study begins with a discussion of the challenges and benefits of analyzing the Arctic as a system. It goes on to discuss current and future needs of the defense, scientific, energy, and intelligence communities for more comprehensive data products related to the Arctic; assess the current state of atmospheric measurement resources available for the Arctic; and explain how the capabilities at Sandia National Laboratories can be used to address the identified technological, data, and modeling needs of the defense, scientific, energy, and intelligence communities for Arctic support.

  14. Impact of climate change on zooplankton communities, seabird populations and arctic terrestrial ecosystem—A scenario

    Science.gov (United States)

    Stempniewicz, Lech; Błachowiak-Samołyk, Katarzyna; Węsławski, Jan M.

    2007-11-01

    Many arctic terrestrial ecosystems suffer from a permanent deficiency of nutrients. Marine birds that forage at sea and breed on land can transport organic matter from the sea to land, and thus help to initiate and sustain terrestrial ecosystems. This organic matter initiates the emergence of local tundra communities, increasing primary and secondary production and species diversity. Climate change will influence ocean circulation and the hydrologic regime, which will consequently lead to a restructuring of zooplankton communities between cold arctic waters, with a dominance of large zooplankton species, and Atlantic waters in which small species predominate. The dominance of large zooplankton favours plankton-eating seabirds, such as the little auk ( Alle alle), while the presence of small zooplankton redirects the food chain to plankton-eating fish, up through to fish-eating birds (e.g., guillemots Uria sp.). Thus, in regions where the two water masses compete for dominance, such as in the Barents Sea, plankton-eating birds should dominate the avifauna in cold periods and recess in warmer periods, when fish-eaters should prevail. Therefore under future anthropogenic climate scenarios, there could be serious consequences for the structure and functioning of the terrestrial part of arctic ecosystems, due in part to changes in the arctic marine avifauna. Large colonies of plankton-eating little auks are located on mild mountain slopes, usually a few kilometres from the shore, whereas colonies of fish-eating guillemots are situated on rocky cliffs at the coast. The impact of guillemots on the terrestrial ecosystems is therefore much smaller than for little auks because of the rapid washing-out to sea of the guano deposited on the seabird cliffs. These characteristics of seabird nesting sites dramatically limit the range of occurrence of ornithogenic soils, and the accompanying flora and fauna, to locations where talus-breeding species occur. As a result of climate

  15. Effects of eutrophication on the planktonic food web dynamics of marine coastal ecosystems: The case study of two tropical inlets.

    Science.gov (United States)

    Schmoker, Claire; Russo, Francesca; Drillet, Guillaume; Trottet, Aurore; Mahjoub, Mohamed-Sofiane; Hsiao, Shih-Hui; Larsen, Ole; Tun, Karenne; Calbet, Albert

    2016-08-01

    We studied the plankton dynamics of two semi-enclosed marine coastal inlets of the north of Jurong Island separated by a causeway (SW Singapore; May 2012-April 2013). The west side of the causeway (west station) has residence times of ca. one year and is markedly eutrophic. The east side (east station) has residence times of one month and presents lower nutrient concentrations throughout the year. The higher nutrient concentrations at the west station did not translate into significantly higher concentrations of chlorophyll a, with the exception of some peaks at the end of the South West Monsoon. Microzooplankton were more abundant at the west station. The west station exhibited more variable abundances of copepods during the year than did the east station, which showed a more stable pattern and higher diversity. Despite the higher nutrient concentrations at the west station (never limiting phytoplankton growth), the instantaneous phytoplankton growth rates there were generally lower than at the east station. The phytoplankton communities at the west station were top-down controlled, largely by microzooplankton grazing, whereas those of the east station alternated between top-down and bottom-up control, with mesozooplankton being the major grazers. Overall, the trophic transfer efficiency from nutrients to mesozooplankton in the eutrophic west station was less efficient than in the east station, but this was mostly because a poor use of inorganic nutrients by phytoplankton rather than an inefficient trophic transfer of carbon. Some hypotheses explaining this result are discussed. PMID:27326462

  16. Bacterial Exopolysaccharides from Extreme Marine Habitats: Production, Characterization and Biological Activities

    Directory of Open Access Journals (Sweden)

    Annarita Poli

    2010-06-01

    Full Text Available Many marine bacteria produce exopolysaccharides (EPS as a strategy for growth, adhering to solid surfaces, and to survive adverse conditions. There is growing interest in isolating new EPS producing bacteria from marine environments, particularly from extreme marine environments such as deep-sea hydrothermal vents characterized by high pressure and temperature and heavy metal presence. Marine EPS-producing microorganisms have been also isolated from several extreme niches such as the cold marine environments typically of Arctic and Antarctic sea ice, characterized by low temperature and low nutrient concentration, and the hypersaline marine environment found in a wide variety of aquatic and terrestrial ecosystems such as salt lakes and salterns. Most of their EPSs are heteropolysaccharides containing three or four different monosaccharides arranged in groups of 10 or less to form the repeating units. These polymers are often linear with an average molecular weight ranging from 1 × 105 to 3 × 105 Da. Some EPS are neutral macromolecules, but the majority of them are polyanionic for the presence of uronic acids or ketal-linked pyruvate or inorganic residues such as phosphate or sulfate. EPSs, forming a layer surrounding the cell, provide an effective protection against high or low temperature and salinity, or against possible predators. By examining their structure and chemical-physical characteristics it is possible to gain insight into their commercial application, and they are employed in several industries. Indeed EPSs produced by microorganisms from extreme habitats show biotechnological promise ranging from pharmaceutical industries, for their immunomodulatory and antiviral effects, bone regeneration and cicatrizing capacity, to food-processing industries for their peculiar gelling and thickening properties. Moreover, some EPSs are employed as biosurfactants and in detoxification mechanisms of petrochemical oil-polluted areas. The aim of

  17. Better retention through game-play - EcoChains: Arctic Crisis card game

    Science.gov (United States)

    Pfirman, S. L.; Lee, J.; O'Garra, T.; Bachrach, E.

    2015-12-01

    Increasingly games are being used in formal and informal education with the goal of improving student/participant understanding of content knowledge through enhanced engagement. While most games are fun by design, few controlled studies have been conducted to assess games' potential for learning gains in comparison with traditional educational approaches. Without evidence for learning, it can be difficult to justify incorporating STEM games in curricula and other programming. In this study we assess the impact of a game called EcoChains (http://thepolarhub.org/project/ecochains-arctic-crisis) on learning, using a controlled experiment. The EcoChains: Arctic Crisis card game gives players the opportunity to learn about the components of an Arctic marine food web, the reliance of some species on sea ice, and the potential impacts of future changes on the ecosystem. EcoChains was developed under the Polar Learning and Responding: PoLAR Climate Change Education Partnership (thepolarhub.org). EcoChains aligns with Next Generation Science Standards LS2 Ecosystems: Interactions, Energy, and Dynamics and ESS3 Earth and Human Activity. Participants in this experiment (n=41) were randomly assigned to either play EcoChains or to read a magazine-style article with similar content (the control). Questionnaires, mapping exercises and a 4-week follow-up survey were used to identify changes in participant knowledge of climate change and the Arctic region, attitudes and beliefs about climate change and its impacts, information-seeking behaviors, systems thinking, impressions of and engagement with the intervention experience. Analysis indicates that the game was as effective as, and in some respects more effective than, the article at teaching participants about climate change and the Arctic region and ecosystems. The follow up survey found that game players recalled new information better than those who read the article. Participants were also more engaged in the game than the

  18. Marine ecosystem appropriation in the Indo-Pacific: a case study of the live reef fish food trade

    Science.gov (United States)

    Warren-Rhodes, Kimberley; Sadovy, Yvonne; Cesar, Herman

    2003-01-01

    Our ecological footprint analyses of coral reef fish fisheries and, in particular, the live reef fish food trade (FT), indicate many countries' current consumption exceeds estimated sustainable per capita global, regional and local coral reef production levels. Hong Kong appropriates 25% of SE Asia's annual reef fish production of 135 260-286 560 tonnes (t) through its FT demand, exceeding regional biocapacity by 8.3 times; reef fish fisheries demand out-paces sustainable production in the Indo-Pacific and SE Asia by 2.5 and 6 times. In contrast, most Pacific islands live within their own reef fisheries means with local demand at unsustainable nature of the FT and the urgent need for regional management and conservation of coral reef fisheries in the Indo-Pacific.

  19. Marine ecosystem appropriation in the Indo-Pacific: a case study of the live reef fish food trade

    Science.gov (United States)

    Warren-Rhodes, Kimberley; Sadovy, Yvonne; Cesar, Herman

    2003-01-01

    Our ecological footprint analyses of coral reef fish fisheries and, in particular, the live reef fish food trade (FT), indicate many countries' current consumption exceeds estimated sustainable per capita global, regional and local coral reef production levels. Hong Kong appropriates 25% of SE Asia's annual reef fish production of 135 260-286 560 tonnes (t) through its FT demand, exceeding regional biocapacity by 8.3 times; reef fish fisheries demand out-paces sustainable production in the Indo-Pacific and SE Asia by 2.5 and 6 times. In contrast, most Pacific islands live within their own reef fisheries means with local demand at < 20% of total capacity in Oceania. The FT annually requisitions up to 40% of SE Asia's estimated reef fish and virtually all of its estimated grouper yields. Our results underscore the unsustainable nature of the FT and the urgent need for regional management and conservation of coral reef fisheries in the Indo-Pacific.

  20. Influence of climate model variability on projected Arctic shipping futures

    Science.gov (United States)

    Stephenson, Scott R.; Smith, Laurence C.

    2015-11-01

    Though climate models exhibit broadly similar agreement on key long-term trends, they have significant temporal and spatial differences due to intermodel variability. Such variability should be considered when using climate models to project the future marine Arctic. Here we present multiple scenarios of 21st-century Arctic marine access as driven by sea ice output from 10 CMIP5 models known to represent well the historical trend and climatology of Arctic sea ice. Optimal vessel transits from North America and Europe to the Bering Strait are estimated for two periods representing early-century (2011-2035) and mid-century (2036-2060) conditions under two forcing scenarios (RCP 4.5/8.5), assuming Polar Class 6 and open-water vessels with medium and no ice-breaking capability, respectively. Results illustrate that projected shipping viability of the Northern Sea Route (NSR) and Northwest Passage (NWP) depends critically on model choice. The eastern Arctic will remain the most reliably accessible marine space for trans-Arctic shipping by mid-century, while outcomes for the NWP are particularly model-dependent. Omitting three models (GFDL-CM3, MIROC-ESM-CHEM, and MPI-ESM-MR), our results would indicate minimal NWP potential even for routes from North America. Furthermore, the relative importance of the NSR will diminish over time as the number of viable central Arctic routes increases gradually toward mid-century. Compared to vessel class, climate forcing plays a minor role. These findings reveal the importance of model choice in devising projections for strategic planning by governments, environmental agencies, and the global maritime industry.

  1. Arctic Shipping Emissions in the Changing Climate

    OpenAIRE

    Vihanninjoki, Vesa

    2014-01-01

    Due to the Arctic climate change and the related diminishing of Arctic sea ice cover, the general conditions for Arctic shipping are changing. The retreat of Arctic sea ice opens up new routes for maritime transportation, both trans-Arctic passages and new alternatives within the Arctic region. Hence the amount of Arctic shipping is presumed to increase. Despite the observed development, the sailing conditions in the Arctic waters will remain challenging. Thus particular attention will be ...

  2. Arctic Bathymetry (batharcst)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The digitally compiled map includes geology, oil and gas field centerpoints, and geologic provinces of the Arctic (North Pole area encircled by 640 N Latitude). The...

  3. Arctic_Bathymetry

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Models project the Arctic Ocean will become undersaturated with respect to carbonate minerals in the next decade. Recent field results indicate parts may already be...

  4. Arctic Geology (geoarcst)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The digitally compiled map includes geology, oil and gas field centerpoints, and geologic provinces of the Arctic (North Pole area encircled by 640 N Latitude). The...

  5. Arctic survey, 1957

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes a survey and game patrol conducted to twelve villages in the Arctic from April 24 to May 2 1957. The report covers animals take for income...

  6. Marine Science, Back Ocean Exploring Marine Mysteries and Utilizing Marine Resources

    OpenAIRE

    Editorial Team

    2011-01-01

    Marine science, fusing biology, physics, chemistry, geology, and engineering together, has become a comprehensive and interdisciplinary sciences. Since the 1950's, many new technologies have bloomed along with the rapid development of marine science. In the twenty first century, human beings are facing severe challenges, such as food and energy shortages, climate warming, environmental degradation, and resource depletion, back to the ocean exploring marine mysteries and utilizing marine resou...

  7. Arctic freshwater synthesis: Introduction

    Science.gov (United States)

    Prowse, T.; Bring, A.; Mârd, J.; Carmack, E.

    2015-11-01

    In response to a joint request from the World Climate Research Program's Climate and Cryosphere Project, the International Arctic Science Committee, and the Arctic Council's Arctic Monitoring and Assessment Program, an updated scientific assessment has been conducted of the Arctic Freshwater System (AFS), entitled the Arctic Freshwater Synthesis (AFSΣ). The major reason for joint request was an increasing concern that changes to the AFS have produced, and could produce even greater, changes to biogeophysical and socioeconomic systems of special importance to northern residents and also produce extra-Arctic climatic effects that will have global consequences. Hence, the key objective of the AFSΣ was to produce an updated, comprehensive, and integrated review of the structure and function of the entire AFS. The AFSΣ was organized around six key thematic areas: atmosphere, oceans, terrestrial hydrology, terrestrial ecology, resources and modeling, and the review of each coauthored by an international group of scientists and published as separate manuscripts in this special issue of Journal of Geophysical Research-Biogeosciences. This AFSΣ—Introduction reviews the motivations for, and foci of, previous studies of the AFS, discusses criteria used to define the domain of the AFS, and details key characteristics of the definition adopted for the AFSΣ.

  8. The Benefit Risk Assessment of Consumption of Marine Species Based on Benefit-Risk Analysis for Foods (BRAFO)-tiered Approach

    Institute of Scientific and Technical Information of China (English)

    GAO Yi Xiong; ZHANG Hong Xia; LI Jing Guang; ZHANG Lei; YU Xin Wei; HE Jia Lu; SHANG Xiao Hong; ZHAO Yun Feng; WU Yong Ning

    2015-01-01

    Objective To assess the net health effect caused by the consumption of specific marine species based on Benefit-Risk Analysis for Foods (BRAFO)-tiered approach. Methods Twenty species were collected from the Zhoushan Archipelago, China. Concentrations of n-3 long-chain polyunsaturated fatty acids, methyl mercury (MeHg), and dioxin-like compounds (DLCs) in the samples were analyzed for benefit risk assessment based on BRAFO-tiered approach. Results Based on the BRAFO-tiered approach, reference scenario (no intake) and alternative scenario (intake of specific species of 200 g/week) were determined. The exposure to MeHg/DLCs via alternative scenario of all studied species did not exceed provisional tolerable weekly/monthly intake. However, the adult population with high DLCs exposure in China would significantly exceed the upper limit of DLCs via an additional alternative scenario of some species such as Auxis thazard. The results of deterministic computation showed that alternative scenario of all studied species generated clear net beneficial effects on death prevention and child IQ gain. Conclusion The alternative scenario of all studied species could be recommended to population with average DLCs exposure, and the reference scenario of species with relatively high DLCs concentration could be recommended to population exposed to high DLCs.

  9. Radioactive contamination in human by polonium-210 in food from marine origin; Contaminacao radioativa humana por Polonio-210 contido em alimento de origem marinha

    Energy Technology Data Exchange (ETDEWEB)

    Kelecom, Alphonse; Gouvea, Rita de Cassia S.; Kelecom, Philippe Marcel [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Biologia Geral. Lab. de Radiobiologia e Radiometria (LARARA)]. E-mail: egbakel@vm.uff.br

    2005-07-01

    Food from marine origin is considered as one of the sources that most contributes to internal radioactive contamination in humans by polonium-210 ({sup 210}Po). This work intended to check whether a single ingestion of the mussel Perna perna should result in a detectable increase of radioactive contamination in the consumer. The mussel was bought at a fish market localized in the city of Niteroi, RJ, Brazil. It was cooked as usually, and its content in {sup 210}Po determined after acid mineralization, spontaneous electrodeposition on stainless steel disks and alpha counting. Non-smoking volunteers maintained for two weeks a normal diet, but completely avoiding fish and seafood. Then, they ate 200 g of cooked mussel, and collected total faeces and urine every day during ten days. {sup 210}Po level in faeces samples showed a 900% increase at the first day after ingestion, and reached normal levels after 3-4 days. In urine samples, the increase of {sup 210}Po was much lower (50%) and reached a maximum at the fifth day. Such data showed a short time permanence of {sup 210}Po in the intestine. Most of ingested {sup 210}Po ({approx}91%) was eliminated in up to 5 days through faeces. A small amount was absorbed ({approx}5-10%), part of it being eliminated in urine, and the remaining contaminated the human body. (author)

  10. Evaluation of carbon-14 (C{sup 14}) levels of terrestrial and marine food products of the environment of the site of Cogema La Hague; Evaluation des niveaux de carbone-14 ({sup 14}C) des denrees alimentaires terrestres et marines de l'environnement du site de COGEMA - La Hague

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-04-15

    This evaluation has for object to inform about the levels in carbon 14 in the environment of the factories of La Hague. Two sectors were differentiated on one hand the terrestrial environment, and on the other hand the marine environment. The investigations concerned first and foremost food products stemming as the vegetable culture (vegetables) or individual breeding (milk, eggs) but also foodstuffs stemming from the local agriculture (cereal). In touch with the second sector, the marine environment, the sampling concerned the accessible products of the sea by all and those locally marketed (fishes, molluscs, shellfishes). The different results are presented in tables. (N.C.)

  11. Cadmium effects in food chain experiments with marine plankton algae (dinophyta) and benthic filter feeders(Tunicata)

    Science.gov (United States)

    Kayser, H.

    The dinoflagellate Scrippsiella faeroense was grown in continuous flow-through cultures (10 1 turbidostat), the outflow leading into vessels containing tunicates of the species Ciona intestinalis, Ascidiella aspersa, Molgula manhattensi and Botryllus schlosseri. The culture medium consisted of natural sea water enriched only with N and P components. CdCl 2 was added to the system at sublethal concentrations. Algal growth wass affected at a Cd ++ concentration of 10 μg·1 -1; sublethal toxicity thresholds of the tunicates ranged from 5 to 10 μg·1 -1. Cadmium accumulation was much higer in the algae than in the tunicates; in spite of the continuous supply of relatively highly Cd contaminated algae, the Cd content of algae-fed tunicates increased insignificantly by comparison with unfed specimens. Only a small percentage of the Cd offered via the food algae was actually assimilated by the ascidians during the first 3 weeks of the experiment. Cd content of the tunicates remained almost constant for the next 2 weeks of the experiment, indicating that ingestion and excretion of the metal was at equilibrium. The concentration factor of Cd decreased through the trophic chain.

  12. Rethinking brain food

    Science.gov (United States)

    If omega-3 (n-3) fatty acids are the functional food du jour, then that "jour" must first have been the 5th day of creation (according to Genesis 1:21), when the marine fish were created and exhorted to be fruitful and multiply. The exact time when these marine species became "brain food" for peopl...

  13. Strategic Assessment for Arctic Observing, and the New Arctic Observing Viewer

    Science.gov (United States)

    Kassin, A.; Cody, R. P.; Manley, W. F.; Gaylord, A. G.; Dover, M.; Score, R.; Lin, D. H.; Villarreal, S.; Quezada, A.; Tweedie, C. E.

    2013-12-01

    Although a great deal of progress has been made with various Arctic Observing efforts, it can be difficult to assess that progress. What data collection efforts are established or under way? Where? By whom? To help meet the strategic needs of SEARCH-AON, SAON, and related initiatives, a new resource has been released: the Arctic Observing Viewer (AOV; http://ArcticObservingViewer.org). This web mapping application covers the 'who', 'what', 'where', and 'when' of data collection sites - wherever marine or terrestrial data are collected. Hundreds of sites are displayed, providing an overview as well as details. Users can visualize, navigate, select, search, draw, print, and more. This application currently showcases a subset of observational activities and will become more comprehensive with time. The AOV is founded on principles of interoperability, with an emerging metadata standard and compatible web service formats, such that participating agencies and organizations can use the AOV tools and services for their own purposes. In this way, the AOV will complement other cyber-resources, and will help science planners, funding agencies, PI's, and others to: assess status, identify overlap, fill gaps, assure sampling design, refine network performance, clarify directions, access data, coordinate logistics, collaborate, and more to meet Arctic Observing goals.

  14. Zooplankton in the Arctic outflow

    Science.gov (United States)

    Soloviev, K. A.; Dritz, A. V.; Nikishina, A. B.

    2009-04-01

    Climate changes in the Arctic cause the changes in the current system that may have cascading effect on the structure of plankton community and consequently on the interlinked and delicately balanced food web. Zooplankton species are by definition incapable to perform horizontal moving. Their transport is connected with flowing water. There are zooplankton species specific for the definite water masses and they can be used as markers for the different currents. That allows us to consider zooplankton community composition as a result of water mixing in the studied area. Little is known however about the mechanisms by which spatial and temporal variability in advection affect dynamics of local populations. Ice conditions are also very important in the function of pelagic communities. Melting time is the trigger to all "plankton blooming" processes, and the duration of ice-free conditions determines the food web development in the future. Fram Strait is one of the key regions for the Arctic: the cold water outflow comes through it with the East Greenland Current and meets warm Atlantic water, the West Spitsbergen Current, producing complicated hydrological situation. During 2007 and 2008 we investigated the structure functional characteristics of zooplankton community in the Fram Strait region onboard KV "Svalbard" (April 2007, April and May 2008) and RV "Jan Mayen" (May 2007, August 2008). This study was conducted in frame of iAOOS Norway project "Closing the loop", which, in turn, was a part of IPY. During this cruises multidisciplinary investigations were performed, including sea-ice observations, CTD and ADCP profiling, carbon flux, nutrients and primary production measurements, phytoplankton sampling. Zooplankton was collected with the Hydro-Bios WP2 net and MultiNet Zooplankton Sampler, (mouth area 0.25 m2, mesh size 180 um).Samples were taken from the depth strata of 2000-1500, 1500-1000, 1000-500,500-200, 200-100, 100-60, 60-30, 30-0 m. Gut fluorescence

  15. The stress hormone corticosterone in a marine top predator reflects short-term changes in food availability

    Science.gov (United States)

    Barrett, Robert T; Erikstad, Kjell E; Sandvik, Hanno; Myksvoll, Mari; Jenni-Eiermann, Susi; Kristensen, Ditte L; Moum, Truls; Reiertsen, Tone K; Vikebø, Frode

    2015-01-01

    In many seabird studies, single annual proxies of prey abundance have been used to explain variability in breeding performance, but much more important is probably the timing of prey availability relative to the breeding season when energy demand is at a maximum. Until now, intraseasonal variation in prey availability has been difficult to quantify in seabirds. Using a state-of-the-art ocean drift model of larval cod Gadus morhua, an important constituent of the diet of common guillemots Uria aalge in the southwestern Barents Sea, we were able to show clear, short-term correlations between food availability and measurements of the stress hormone corticosterone (CORT) in parental guillemots over a 3-year period (2009–2011). The model allowed the extraction of abundance and size of cod larvae with very high spatial (4 km) and temporal resolutions (1 day) and showed that cod larvae from adjacent northern spawning grounds in Norway were always available near the guillemot breeding colony while those from more distant southerly spawning grounds were less frequent, but larger. The latter arrived in waves whose magnitude and timing, and thus overlap with the guillemot breeding season, varied between years. CORT levels in adult guillemots were lower in birds caught after a week with high frequencies of southern cod larvae. This pattern was restricted to the two years (2009 and 2010) in which southern larvae arrived before the end of the guillemot breeding season. Any such pattern was masked in 2011 by already exceptionally high numbers of cod larvae in the region throughout chick-rearing period. The findings suggest that CORT levels in breeding birds increase when the arrival of southern sizable larvae does not match the period of peak energy requirements during breeding. PMID:25859335

  16. Upper Arctic Ocean water masses harbor distinct communities of heterotrophic flagellates

    Science.gov (United States)

    Monier, A.; Terrado, R.; Thaler, M.; Comeau, A.; Medrinal, E.; Lovejoy, C.

    2013-06-01

    The ubiquity of heterotrophic flagellates (HFL) in marine waters has been recognized for several decades, but the phylogenetic diversity of these small (ca. 0.8-20 μm cell diameter), mostly phagotrophic protists in the upper pelagic zone of the ocean is underappreciated. Community composition of microbes, including HFL, is the result of past and current environmental selection, and different taxa may be indicative of food webs that cycle carbon and energy very differently. While all oceanic water columns can be density stratified due to the temperature and salinity characteristics of different water masses, the Arctic Ocean is particularly well stratified, with nutrients often limiting in surface waters and most photosynthetic biomass confined to a subsurface chlorophyll maximum layer, where light and nutrients are both available. This physically well-characterized system provided an opportunity to explore the community diversity of HFL from different water masses within the water column. We used high-throughput DNA sequencing techniques as a rapid means of surveying the diversity of HFL communities in the southern Beaufort Sea (Canada), targeting the surface, the subsurface chlorophyll maximum layer (SCM) and just below the SCM. In addition to identifying major clades and their distribution, we explored the micro-diversity within the globally significant but uncultivated clade of marine stramenopiles (MAST-1) to examine the possibility of niche differentiation within the stratified water column. Our results strongly suggested that HFL community composition was determined by water mass rather than geographical location across the Beaufort Sea. Future work should focus on the biogeochemical and ecological repercussions of different HFL communities in the face of climate-driven changes to the physical structure of the Arctic Ocean.

  17. Upper Arctic Ocean water masses harbor distinct communities of heterotrophic flagellates

    Directory of Open Access Journals (Sweden)

    A. Monier

    2013-02-01

    Full Text Available The ubiquity of heterotrophic flagellates (HFL in marine waters has been recognized for several decades, but the phylogenetic diversity of these small (ca. 0.8–20 μm cell diameter, mostly phagotrophic protists in the pelagic zone of the ocean is underappreciated. Community composition of microbes, including HFL, is the result of past and current environmental selection, and different taxa may be indicative of food webs that cycle carbon and energy very differently. While all oceanic water columns can be density stratified due to the temperature and salinity characteristics of different water masses, the Arctic Ocean is particularly well stratified, with nutrients often limiting in surface waters and most photosynthetic biomass confined to a subsurface chlorophyll maximum (SCM layer. This physically well-characterized system provided an opportunity to explore the community diversity of HFL across a wide region, and down the water column. We used high-throughput DNA sequencing techniques as a rapid means of surveying the diversity of HFL communities in the southern Beaufort Sea (Canada, targeting the surface, the SCM and just below the SCM. In addition to identifying major clades and their distribution, we explored the micro-diversity within the globally significant but uncultivated clade of marine stramenopiles (MAST-1 to examine the possibility of niche differentiation within the stratified water column. Our results strongly implied that HFL community composition was determined by water mass rather than geographical location across the Beaufort Sea. Future work should focus on the biogeochemical and ecological repercussions of different HFL communities in the face of climate driven changes to the physical structure of the Arctic Ocean.

  18. Upper Arctic Ocean water masses harbor distinct communities of heterotrophic flagellates

    Directory of Open Access Journals (Sweden)

    A. Monier

    2013-06-01

    Full Text Available The ubiquity of heterotrophic flagellates (HFL in marine waters has been recognized for several decades, but the phylogenetic diversity of these small (ca. 0.8–20 μm cell diameter, mostly phagotrophic protists in the upper pelagic zone of the ocean is underappreciated. Community composition of microbes, including HFL, is the result of past and current environmental selection, and different taxa may be indicative of food webs that cycle carbon and energy very differently. While all oceanic water columns can be density stratified due to the temperature and salinity characteristics of different water masses, the Arctic Ocean is particularly well stratified, with nutrients often limiting in surface waters and most photosynthetic biomass confined to a subsurface chlorophyll maximum layer, where light and nutrients are both available. This physically well-characterized system provided an opportunity to explore the community diversity of HFL from different water masses within the water column. We used high-throughput DNA sequencing techniques as a rapid means of surveying the diversity of HFL communities in the southern Beaufort Sea (Canada, targeting the surface, the subsurface chlorophyll maximum layer (SCM and just below the SCM. In addition to identifying major clades and their distribution, we explored the micro-diversity within the globally significant but uncultivated clade of marine stramenopiles (MAST-1 to examine the possibility of niche differentiation within the stratified water column. Our results strongly suggested that HFL community composition was determined by water mass rather than geographical location across the Beaufort Sea. Future work should focus on the biogeochemical and ecological repercussions of different HFL communities in the face of climate-driven changes to the physical structure of the Arctic Ocean.

  19. Arctic Rabies – A Review

    Directory of Open Access Journals (Sweden)

    Prestrud Pål

    2004-03-01

    Full Text Available Rabies seems to persist throughout most arctic regions, and the northern parts of Norway, Sweden and Finland, is the only part of the Arctic where rabies has not been diagnosed in recent time. The arctic fox is the main host, and the same arctic virus variant seems to infect the arctic fox throughout the range of this species. The epidemiology of rabies seems to have certain common characteristics in arctic regions, but main questions such as the maintenance and spread of the disease remains largely unknown. The virus has spread and initiated new epidemics also in other species such as the red fox and the racoon dog. Large land areas and cold climate complicate the control of the disease, but experimental oral vaccination of arctic foxes has been successful. This article summarises the current knowledge and the typical characteristics of arctic rabies including its distribution and epidemiology.

  20. Effects of sample preparation on stable isotope ratios of carbon and nitrogen in marine invertebrates: implications for food web studies using stable isotopes.

    Science.gov (United States)

    Mateo, Miguel A; Serrano, Oscar; Serrano, Laura; Michener, Robert H

    2008-08-01

    Trophic ecology has benefitted from the use of stable isotopes for the last three decades. However, during the last 10 years, there has been a growing awareness of the isotopic biases associated with some pre-analytical procedures that can seriously hamper the interpretation of food webs. We have assessed the extent of such biases by: (1) reviewing the literature on the topic, and (2) compiling C and N isotopic values of marine invertebrates reported in the literature with the associated sample preparation protocols. The factors considered were: acid-washing, distilled water rinsing (DWR), sample type (whole individuals or pieces of soft tissues), lipid content, and gut contents. Two-level ANOVA revealed overall large and highly significant effects of acidification for both delta(13)C values (up to 0.9 per thousand decrease) and delta(15) N values (up to 2.1 per thousand decrease in whole individual samples, and up to 1.1 per thousand increase in tissue samples). DWR showed a weak overall effect with delta(13)C increments of 0.6 per thousand (for the entire data set) or decrements of 0.7 per thousand in delta(15) N values (for tissue samples). Gut contents showed no overall significant effect, whereas lipid extraction resulted in the greatest biases in both isotopic signatures (delta(13)C, up to -2.0 per thousand in whole individuals; delta(15)N, up to +4.3 per thousand in tissue samples). The study analyzed separately the effects of the various factors in different taxonomic groups and revealed a very high diversity in the extent and direction of the effects. Maxillopoda, Gastropoda, and Polychaeta were the classes that showed the largest isotopic shifts associated with sample preparation. Guidelines for the standardization of sample preparation protocols for isotopic analysis are proposed both for large and small marine invertebrates. Broadly, these guidelines recommend: (1) avoiding both acid washing and DWR, and (2) performing lipid extraction and gut

  1. Regional variability of a projected sea ice-free Arctic during the summer months

    Science.gov (United States)

    Laliberté, F.; Howell, S. E. L.; Kushner, P. J.

    2016-01-01

    Climate projections of sea ice retreat under anthropogenic climate change at the regional scale and in summer months other than September have largely not been evaluated. Information at this level of detail is vital for future planning of safe Arctic marine activities. Here the timing of when Arctic waters will be reliably ice free across Arctic regions from June to October is presented. It is shown that during this century regions along the Northern Sea Route and Arctic Bridge will be more reliably ice free than regions along the Northwest Passage and the Transpolar Sea Route, which will retain substantial sea ice cover past midcentury. Moreover, ice-free conditions in the Arctic will likely be confined to September for several decades to come in many regions. Projections using a selection of models that accounts for agreement of models in each region and calendar month with observations yield similar conclusions.

  2. Shoreface of the Arctic seas - a natural laboratory for subsea permafrost dynamics

    OpenAIRE

    Are, Felix E.

    2003-01-01

    Subsea permafrost on the Arctic shelf occupies some 13 million km2, but is poorly understood. Mathematical modeling, based on the differential equation of heat conduction, is widely used for the compilation of predictive permafrost maps. Realistic geocryological conditions on the Arctic shelf cannot however be explained simply by heat conduction. Laboratory and field investigations show that heat convection and mass transfer play an important role in marine permafrost dynamics. Correspondingl...

  3. Species richness and distribution of chondrichthyan fishes in the Arctic Ocean and adjacent seas

    DEFF Research Database (Denmark)

    Lynghammar, A.; Christiansen, J. S.; Mecklenburg, C. W.;

    2013-01-01

    The sea ice cover decreases and human activity increases in Arctic waters. Fisheries and bycatch issues, shipping and petroleum exploitation (pollution issues) make it imperative to establish biological baselines for the marine fishes inhabiting the Arctic Ocean and adjacent seas (AOAS). Species ...... to be developed in the AOAS, but the precautionary principle should be implemented as abundances, basic taxonomy and biology are still largely unknown. © 2013 Copyright Taylor and Francis Group, LLC....

  4. More Arctic research needed

    Science.gov (United States)

    Bush, Susan

    The desire to achieve a balance between Arctic and Antarctic study was the message of the Senate Committee on Commerce, Science, and Transportation, which heard testimony on the need for more Arctic research on April 24. Ted Stevens (R-Alaska) noted that since 1986, study in the area has not increased as the National Science Foundation has claimed, but rather, owing to inflation, has merely kept pace. Robert Correll, assistant director of geosciences at NSF and chair of the Interagency Arctic Oceans Working Group, gave several reasons why the Arctic is an important area for study by the scientific community. Its unique environment, he said, makes it a natural laboratory. And due to its environmental sensitivity, it may provide one of the earliest indicators of global climate change. Also, its geographic location makes it a “window on space,” some of the world's largest mineral and petroleum resources are in the Arctic, and the region has great strategic and military importance.

  5. Spatial ecotoxicology: migratory Arctic seabirds are exposed to mercury contamination while overwintering in the northwest Atlantic.

    Science.gov (United States)

    Fort, Jérôme; Robertson, Gregory J; Grémillet, David; Traisnel, Gwendoline; Bustamante, Paco

    2014-10-01

    Arctic organisms are exposed to various levels of pollutants, among which mercury (Hg) has raised important environmental concerns. Previous studies examining Hg levels, trends, and effects on Arctic marine top predators have focused on the Arctic region. However, many of these top predators, such as seabirds, migrate to spend a large part of their life cycle far from the Arctic in areas where their exposure to contaminants is largely unknown. By combining biotelemetry and Hg and stable isotope analyses, we studied the seasonal Hg contamination of little auks (Alle alle, the most abundant Arctic seabird) in relation to their distribution and marine foraging habitat, as well as its potential impacts on bird reproduction. We show that little auks were ∼ 3.5 times more contaminated when outside the breeding season, and that Hg that accumulated during this nonbreeding non-Arctic period was related to egg size the following season, with females having more Hg laying smaller eggs. Our results highlight that ecotoxicological studies should be expanded to yield a comprehensive understanding of contamination risks and associated threats to top predators over their entire annual cycle. Furthermore, we show that an important nonbreeding area located in the northwest Atlantic was associated with greater Hg contamination and demonstrate the utility of bird-borne miniaturized technology for evaluating the contamination of marine systems on large spatial scales.

  6. Transferencia de recursos alimentarios entre diferentes ambientes del ecosistema marino Transfer of food resources among different environments in the marine ecosystem

    Directory of Open Access Journals (Sweden)

    SEBASTIAN R. RODRIGUEZ

    2000-03-01

    Full Text Available Por décadas los ecólogos han centrado sus estudios en interacciones que involucran elementos de un mismo sistema, poniendo poco énfasis en aquellas que involucran elementos de ambientes aledaños. Estudios desarrollados en los últimos años han vuelto a llamar la atención respecto de la frecuencia con la que ocurre transferencia de energía (en la forma de nutrientes o alimento entre sistemas, ambientes y/o hábitats ecológicos, y las consecuencias de estos aportes energéticos a nivel poblacional o comunitario a distintas escalas espaciales y temporales en los sistemas involucrados. En la presente revisión se describen las vías de transferencia de energía más comunes de observar en el ecosistema marino, poniendo especial énfasis en el flujo de recursos tróficos (i.e., algas a la deriva y detritus desde bosques de macroalgas pardas submareales hacia ambientes intermareales en los sistemas templadosFor decades ecologists have focused their studies in interactions among elements of the same system, putting low emphasis in those that involve elements of border environments. Studies carried out in the last years have called the attention respect the frequent ocurrence of energy transfer (as nutrients or food among ecological systems, environments and/or habitats, and the consequences of these energy contributions at population or community levels and at different spatial and temporal scales. In this review the ways of energy transfer more commonly observed in the marine ecosystem are described. The flow of trophic resources (i.e., drift algae and detritus from subtidal kelps to intertidal environments in template systems, are emphasized

  7. Research advances on microbial food loop in marine ecosystem%海洋微食物环研究新进展

    Institute of Scientific and Technical Information of China (English)

    李洪波; 杨青; 周峰

    2012-01-01

    The microbial food loop is an important material and energy process in the marine ecosystem. It is summarized that how to analyze the abundance and biomass of microbe in microbial loop and study trends. At the same time, the effects of environmental factors,I, e. Eutrophication,climate change,et al. On microbial loop are discussed.%微食物环是海洋生态系统中重要的物质和能量过程,是传统食物链的有效补充.本文针对目前我国海洋微食物环结构组成的研究现状以及最新研究动态,对微食物环的生物组成成分,包括微微型浮游生物、nano-浮游动物、micro-浮游动物以及病毒的生态作用加以阐述,同时针对环境因素的改变,如富营养化、浮游植物水华过程和气候变化如何影响微食物环进行了分析,并对我国未来微食物环研究进行了展望.微型生物及微食物环如何应对新型生态压力,尤其是对气候改变的响应策略将会是下一步海洋生态系统研究的一个热点.

  8. Ship emissions measurement in the Arctic by plume intercepts of the Canadian Coast Guard icebreaker Amundsen from the Polar 6 aircraft platform

    OpenAIRE

    Aliabadi, Amir A.; Thomas, Jennie L.; Herber, Andreas B.; Staebler, Ralf M.; Leaitch, W. Richard; Schulz, Hannes; Law, Kathy S.; Marelle, Louis; Burkart, Julia; Willis, Megan D.; Bozem, Heiko; Hoor, Peter M.; Köllner, Franziska; Schneider, Johannes; Levasseur, Maurice

    2016-01-01

    Decreasing sea ice and increasing marine navigability in northern latitudes have changed Arctic ship traffic patterns in recent years and are predicted to increase annual ship traffic in the Arctic in the future. Development of effective regulations to manage environmental impacts of shipping requires an understanding of ship emissions and atmospheric processing in the Arctic environment. As part of the summer 2014 NETCARE (Network on Climate and Aerosols) campaign, the plum...

  9. Environmental contaminants and human health in the Canadian Arctic.

    Science.gov (United States)

    Donaldson, S G; Van Oostdam, J; Tikhonov, C; Feeley, M; Armstrong, B; Ayotte, P; Boucher, O; Bowers, W; Chan, L; Dallaire, F; Dallaire, R; Dewailly, E; Edwards, J; Egeland, G M; Fontaine, J; Furgal, C; Leech, T; Loring, E; Muckle, G; Nancarrow, T; Pereg, D; Plusquellec, P; Potyrala, M; Receveur, O; Shearer, R G

    2010-10-15

    The third Canadian Arctic Human Health Assessment conducted under the Canadian Northern Contaminants Program (NCP), in association with the circumpolar Arctic Monitoring and Assessment Programme (AMAP), addresses concerns about possible adverse health effects in individuals exposed to environmental contaminants through a diet containing country foods. The objectives here are to: 1) provide data on changes in human contaminant concentrations and exposure among Canadian Arctic peoples; 2) identify new contaminants of concern; 3) discuss possible health effects; 4) outline risk communication about contaminants in country food; and 5) identify knowledge gaps for future contaminant research and monitoring. The nutritional and cultural benefits of country foods are substantial; however, some dietary studies suggest declines in the amount of country foods being consumed. Significant declines were found for most contaminants in maternal blood over the last 10 years within all three Arctic regions studied. Inuit continue to have the highest levels of almost all persistent organic pollutants (POPs) and metals among the ethnic groups studied. A greater proportion of people in the East exceed Health Canada's guidelines for PCBs and mercury, although the proportion of mothers exceeding these guidelines has decreased since the previous assessment. Further monitoring and research are required to assess trends and health effects of emerging contaminants. Infant development studies have shown possible subtle effects of prenatal exposure to heavy metals and some POPs on immune system function and neurodevelopment. New data suggest important beneficial effects on brain development for Inuit infants from some country food nutrients. The most successful risk communication processes balance the risks and benefits of a diet of country food through input from a variety of regional experts and the community, to incorporate the many socio-cultural and economic factors to arrive at a risk

  10. Marine Anthropogenic Litter

    OpenAIRE

    Bergmann, Melanie; Gutow, Lars; Klages, Michael

    2015-01-01

    This book describes how manmade litter, primarily plastic, has spread into the remotest parts of the oceans and covers all aspects of this pollution problem from the impacts on wildlife and human health to socio-economic and political issues. Marine litter is a prime threat to marine wildlife, habitats and food webs worldwide. The book illustrates how advanced technologies from deep-sea research, microbiology and mathematic modelling as well as classic beach litter counts by volunteers co...

  11. Psychrophilic sulfate-reducing bacteria isolated from permanently cold Arctic marine sediments: description of Desulfofrigrus oceanense gen. nov., sp nov., Desulfofrigus fragile sp nov., Desulfofaba gelida gen. nov., sp nov., Desulfotalea psychrophila gen. nov., sp nov and Desulfotalea arctica sp

    DEFF Research Database (Denmark)

    Knoblauch, C.; Sahm, K.; Jørgensen, BB

    1999-01-01

    Five psychrophilic, Gram-negative, sulfate-reducing bacteria were isolated from marine sediments off the coast of Svalbard. All isolates grew at the in situ temperature of -1.7 degrees C. In batch cultures, strain PSv29(T) had the highest growth rate at 7 degrees C, strains ASv26(T) and LSv54(T...

  12. Response of the Arctic pteropod Limacina helicina to projected future environmental conditions.

    Directory of Open Access Journals (Sweden)

    Steeve Comeau

    Full Text Available Thecosome pteropods (pelagic mollusks can play a key role in the food web of various marine ecosystems. They are a food source for zooplankton or higher predators such as fishes, whales and birds that is particularly important in high latitude areas. Since they harbor a highly soluble aragonitic shell, they could be very sensitive to ocean acidification driven by the increase of anthropogenic CO(2 emissions. The effect of changes in the seawater chemistry was investigated on Limacina helicina, a key species of Arctic pelagic ecosystems. Individuals were kept in the laboratory under controlled pCO(2 levels of 280, 380, 550, 760 and 1020 microatm and at control (0 degrees C and elevated (4 degrees C temperatures. The respiration rate was unaffected by pCO(2 at control temperature, but significantly increased as a function of the pCO(2 level at elevated temperature. pCO(2 had no effect on the gut clearance rate at either temperature. Precipitation of CaCO(3, measured as the incorporation of (45Ca, significantly declined as a function of pCO(2 at both temperatures. The decrease in calcium carbonate precipitation was highly correlated to the aragonite saturation state. Even though this study demonstrates that pteropods are able to precipitate calcium carbonate at low aragonite saturation state, the results support the current concern for the future of Arctic pteropods, as the production of their shell appears to be very sensitive to decreased pH. A decline of pteropod populations would likely cause dramatic changes to various pelagic ecosystems.

  13. Arctic species resilience

    DEFF Research Database (Denmark)

    Mortensen, Lars O.; Forchhammer, Mads C.; Jeppesen, Erik

    The peak of biological activities in Arctic ecosystems is characterized by a relative short and intense period between the start of snowmelt until the onset of frost. Recent climate changes have induced larger seasonal variation in both timing of snowmelt as well as changes mean temperatures and ...... and resources. This poster will present the conceptual framework for this project focusing on species resilience......., an extensive monitoring program has been conducted in the North Eastern Greenland National Park, the Zackenberg Basic. The objective of the program is to provide long time series of data on the natural innate oscillations and plasticity of a High Arctic ecosystem. With offset in the data provided through...

  14. Arctic Legal System: a New Sustainable Development Model

    Directory of Open Access Journals (Sweden)

    Kumar Sahu Manjeet

    2016-01-01

    Full Text Available Historically, the term ‘Arctic’ was used synonymously with the term ‘ice’, but climate change and Arctic hydrocarbon grabbed the attention of the world community as an opportunity to make the Arctic an ‘Energy Hub’. Exploration of oil and gas over the past six decades in the Arctic has made the region as places in the world. All major players in the market have endeavored to approach this new energy basket to utilize its maximum benefit. Commercial exploitation of natural resources has made this place a center for the regulation of oil and gas activities. However, petroleum exploration and its operation have had significant local detrimental impacts on the atmosphere, inhabitants and marine environment. Geologists have always believed in the huge reserves of oil and gas in the Arctic Region. However, the exploration of oil and gas started as recently as the mid-1950s. An increase in the demand of oil and gas in the international market, as well as its growing scarcity, compelled the world to locate oil and gas reserves in various regions. It is significant to note that the Arctic states are strategically going to control the excessive exploitation of Arctic hydrocarbon with much profitability. However, it is still a far sighted question ‘whether Arctic will provide direct competition to the Middle East’ and become another hub in the energy market.

  15. Bromine measurements in ozone depleted air over the Arctic Ocean

    Directory of Open Access Journals (Sweden)

    J. A. Neuman

    2010-07-01

    Full Text Available In situ measurements of ozone, photochemically active bromine compounds, and other trace gases over the Arctic Ocean in April 2008 are used to examine the chemistry and geographical extent of ozone depletion in the arctic marine boundary layer (MBL. Data were obtained from the NOAA WP-3D aircraft during the Aerosol, Radiation, and Cloud Processes affecting Arctic Climate (ARCPAC study and the NASA DC-8 aircraft during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS study. Fast (1 s and sensitive (detection limits at the low pptv level measurements of BrCl and BrO were obtained from three different chemical ionization mass spectrometer (CIMS instruments, and soluble bromide was measured with a mist chamber. The CIMS instruments also detected Br2. Subsequent laboratory studies showed that HOBr rapidly converts to Br2 on the Teflon instrument inlets. This detected Br2 is identified as active bromine and represents a lower limit of the sum HOBr + Br2. The measured active bromine is shown to likely be HOBr during daytime flights in the arctic. In the MBL over the Arctic Ocean, soluble bromide and active bromine were consistently elevated and ozone was depleted. Ozone depletion and active bromine enhancement were confined to the MBL that was capped by a temperature inversion at 200–500 m altitude. In ozone-depleted air, BrO rarely exceeded 10 pptv and was always substantially lower than soluble bromide that was as high as 40 pptv. BrCl was rarely enhanced above the 2 pptv detection limit, either in the MBL, over Alaska, or in the arctic free troposphere.

  16. Arctic Ocean Gravity Field Derived From ERS-1 Satellite Altimetry.

    Science.gov (United States)

    Laxon, S; McAdoo, D

    1994-07-29

    The derivation of a marine gravity field from satellite altimetry over permanently ice-covered regions of the Arctic Ocean provides much new geophysical information about the structure and development of the Arctic sea floor. The Arctic Ocean, because of its remote location and perpetual ice cover, remains from a tectonic point of view the most poorly understood ocean basin on Earth. A gravity field has been derived with data from the ERS-1 radar altimeter, including permanently ice-covered regions. The gravity field described here clearly delineates sections of the Arctic Basin margin along with the tips of the Lomonosov and Arctic mid-ocean ridges. Several important tectonic features of the Amerasia Basin are clearly expressed in this gravity field. These include the Mendeleev Ridge; the Northwind Ridge; details of the Chukchi Borderland; and a north-south trending, linear feature in the middle of the Canada Basin that apparently represents an extinct spreading center that "died" in the Mesozoic. Some tectonic models of the Canada Basin have proposed such a failed spreading center, but its actual existence and location were heretofore unknown. PMID:17752757

  17. A Scientific Synthesis and Assessment of the Arctic Carbon Cycle

    Science.gov (United States)

    Hayes, Daniel J.; Guo, Laodong; McGuire, A. David

    2007-06-01

    The Arctic Monitoring and Assessment Programme (AMAP), along with the Climate and Cryosphere (CliC) Project and the International Arctic Science Committee (IASC), sponsored the Arctic Carbon Cycle Assessment Workshop, at the Red Lion Hotel in Seattle, Wash., between 27 February and 1 March 2007. The workshop was held in a general effort toward the scientific synthesis and assessment of the Arctic system carbon cycle, as well as to generate feedback on the working draft of an assessment document. The initial assessment was prepared by the Arctic carbon cycle assessment writing team, which is led by A. David McGuire (University of Alaska Fairbanks) and includes Leif Anderson (Goteborg University, Sweden), Torben Christensen (Lund University, Sweden), Scott Dallimore (Natural Resources Canada), Laodong Guo (University of Southern Mississippi), Martin Heimann (Max Planck Institute, Germany), Robie MacDonald (Department of Fisheries and Oceans, Canada), and Nigel Roulet (McGill University, Canada). The workshop brought together leading researchers in the fields of terrestrial, marine, and atmospheric science to report on and discuss the current state of knowledge on contemporary carbon stocks and fluxes in the Artie and their potential responses to a changing climate. The workshop was attended by 35 scientists representing institutions from 10 countries in addition to two representatives of the sponsor agencies (John Calder for AMAP and Diane Verseghy for CliC).

  18. The surface Arctic Ocean: A dynamic reservoir of terrigenous dissolved organic carbon

    Science.gov (United States)

    Hansell, D. A.; Letscher, R. T.

    2012-04-01

    The upper mixed layer of the Arctic Ocean is a globally important sink for dissolved organic matter mobilized from adjacent continents, which in turn are subject to substantial changes with warming of the Arctic system. Understanding the dynamics and fate of this terrigenous material has become critical for our understanding the contributions of the Arctic to the global carbon cycle. Terrigenous dissolved organic carbon (tDOC) had long been viewed as highly conserved within the Arctic Ocean, yet only a fraction of that entering from the rivers survived for export to the North Atlantic. Extensive surveys of tDOC and other tracers between the shelves and the waters overlying the deep basins indicate that a large fraction of the tDOC is subject to slow mineralization. The extent of removal within the Arctic system depends then on the time scale for water mass retention; the longer the retention, the greater the remineralization within the Arctic. Remineralization of tDOC adds to the inorganic carbon inventory and seawater pCO2, thus impacting exchange of CO2 with the atmosphere. This talk will begin with a global view of marine dissolved organic carbon (DOC), from which the context for tDOC in the Arctic Ocean will be established. The surface Arctic Ocean distribution of tDOC will be presented, along with consideration of its dynamics and export to the North Atlantic.

  19. National Oceanic and Atmospheric Administration(NOAA) Arctic Climate Change Studies: A Contribution to IPY

    Science.gov (United States)

    Calder, J.; Overland, J.; Uttal, T.; Richter-Menge, J.; Rigor, I.; Crane, K.

    2004-12-01

    NOAA has initiated four activities that respond to the Arctic Climate Impact Assessment(ACIA) recommendations and represent contributions toward the IPY: 1) Arctic cloud, radiation and aerosol observatories, 2) documentation and attribution of changes in sea-ice thickness through direct measurement and modeling, 3) deriving added value from existing multivariate and historical data, and 4) following physical and biological changes in the northern Bering and Chukchi Seas. Northeast Canada, the central Arctic coast of Russia and the continuing site at Barrow have been chosen as desirable radiation/cloud locations as they exhibit different responses to Arctic Oscillation variability. NOAA is closely collaborating with Canadian groups to establish an observatory at Eureka. NOAA has begun deployment of a network of ice-tethered ice mass balance buoys complemented by several ice profiling sonars. In combination with other sea ice investigators, the Arctic buoy program, and satellites, changes can be monitored more effectively in sea ice throughout the Arctic. Retrospective data analyses includes analysis of Arctic clouds and radiation from surface and satellite measurements, correction of systematic errors in TOVS radiance data sets for the Arctic which began in 1979, addressing the feasibility of an Arctic System Reanalysis, and an Arctic Change Detection project that incorporates historical and recent physical and biological observations and news items at a website, www.arctic.noaa.gov. NOAA has begun a long-term effort to detect change in ecosystem indicators in the northern Bering and Chukchi Seas that could provide a model for other northern marine ecosystems. The first efforts were undertaken in summer 2004 during a joint Russian-US cruise that mapped the regions physical, chemical and biological parameters to set the stage for future operations over the longer term. A line of biophysical moorings provide detection of the expected warming of this area. A

  20. Marine meiofauna, carbon and nitrogen mineralization in sandy and soft sediments of Disko Bay, West Greenland

    DEFF Research Database (Denmark)

    Rysgaard, S.; Christensen, P.B.; Sørensen, Martin Vinther;

    2000-01-01

    and was, together with organotrophic O-2 respiration, the most important pathway for carbon mineralization within these sediments. The obtained process rates were comparable to mineralization rates from much warmer localities, suggesting that benthic mineralization in arctic marine environments...

  1. The Arctic Circle

    Science.gov (United States)

    McDonald, Siobhan

    2016-04-01

    My name is Siobhan McDonald. I am a visual artist living and working in Dublin. My studio is based in The School of Science at University College Dublin where I was Artist in Residence 2013-2015. A fascination with time and the changeable nature of landmass has led to ongoing conversations with scientists and research institutions across the interweaving disciplines of botany, biology and geology. I am developing a body of work following a recent research trip to the North Pole where I studied the disappearing landscape of the Arctic. Prompted by my experience of the Arctic shelf receding, this new work addresses issues of the instability of the earth's materiality. The work is grounded in an investigation of material processes, exploring the dynamic forces that transform matter and energy. This project combines art and science in a fascinating exploration of one of the Earth's last relatively untouched wilderness areas - the High Arctic to bring audiences on journeys to both real and artistically re-imagined Arctic spaces. CRYSTALLINE'S pivotal process is collaboration: with The European Space Agency; curator Helen Carey; palaeontologist Prof. Jenny McElwain, UCD; and with composer Irene Buckley. CRYSTALLINE explores our desire to make corporeal contact with geological phenomena in Polar Regions. From January 2016, in my collaboration with Jenny McElwain, I will focus on the study of plants and atmospheres from the Arctic regions as far back as 400 million years ago, to explore the essential 'nature' that, invisible to the eye, acts as imaginary portholes into other times. This work will be informed by my arctic tracings of sounds and images recorded in the glaciers of this disappearing frozen landscape. In doing so, the urgencies around the tipping of natural balances in this fragile region will be revealed. The final work will emerge from my forthcoming residency at the ESA in spring 2016. Here I will conduct a series of workshops in ESA Madrid to work with

  2. Food web magnificaton of persistent organic pollutants in poikilotherms and homeotherms.

    Science.gov (United States)

    Hop, Haakon; Borgá, Katrine; Gabrielsen, Geir Wing; Kleivane, Lars; Skaare, Janneche Utne

    2002-06-15

    Food web magnification of persistent organic pollutants (POPs) was determined for the Barents Sea food web using 615N as a continuous variable for assessing trophic levels (TL). The food web investigated comprised zooplankton, ice fauna and fish (poikilotherms, TL 1.7-3.3), and seabirds and seals (homeotherms, TL 3.3-4.2), with zooplankton representing the lowest and glaucous gull the highest trophic level. Concentrations of lipophilic and persistent organochlorines were orders of magnitude higher in homeotherms than in poikilotherms. These compounds had significantly higher rates of increase per trophic level in homeotherms relative to poikilotherms, with the highest food web magnification factors (FWMFs) for cischlordane and p,p'-DDE. Some compounds, such as transnonachlor and HCB, had similar rates of increase throughout the food web, whereas compounds that are more readily eliminated (gamma-HCH) showed no relationship with trophic level. It is preferable to calculate FWMFs with regard to thermal groups, because the different energy requirements and biotransformation abilities between poikilotherms and homeotherms may give different rates of contaminant increase with trophic level. When biomagnification is compared between ecosystems, FWMFs are preferable to single predator-prey biomagnification factors. FWMFs represent a trophic level increase of contaminants that is average for the food chain rather than an increase for a specific predator-prey relationship. The Barents Sea FWMFs were generally comparable to those determined for marine food webs with similar food chain lengths in the Canadian Arctic. PMID:12099454

  3. Distribution of marine birds on Georges Bank and adjacent waters. Technical progress report, 1 January--31 August 1978

    Energy Technology Data Exchange (ETDEWEB)

    Powers, K.D.

    1978-10-01

    The work accomplished during the period covered in this technical progress report demonstrates the importance, interest, and necessity of a distribution study of marine birds in the Georges Bank area on a national and international scale. Cooperation was extended by the U.S. National Marine Fisheries Service, U.S. Fish and Wildlife Service, U.S. Coast Guard, and by the Canadian Wildlife Service, Halifax, N.S., AltantNIRO, Kaliningrad, USSR, and Federal Republic of Germany. Two sampling methods, fixed-area and total bird counts, were effectively employed, which allow comparable data bases with marine bird distribution information being collected in the North Pacific, Bering and Chukchi Seas (Outer Continental Shelf Energy Assessment Program), and in the North Atlantic and Canadian Arctic (CWS and The Seabird Group). A marine bird data retrieval bank is being developed for MBO seabird data at the USFWS Migratory Bird and Habitat Research Laboratory. A food habits bibliography and prey item/bird species summary table for marine birds in the western North Atlantic has been prepared from existing literature. Unpublished NMFS data on zooplankton/ichthyoplankton, and ground fish is being made available for possible correlations in distribution of selected prey items with bird species.

  4. Some discussions on Arctic vortex

    Institute of Scientific and Technical Information of China (English)

    Li Hai; Sun Lantao; Wu Huiding; Li Xiang

    2006-01-01

    The Arctic vortex is a persistent large-scale cyclonic circulation in the middle and upper troposphere and the stratosphere. Its activity and variation control the semi-permanent active centers of Pan-Arctic and the short-time cyclone activity in the subarctic areas. Its strength variation, which directly relates to the atmosphere, ocean, sea ice and ecosystem of the Arctic, can affect the lower atmospheric circulation, the weather of subarctic area and even the weather of middle latitude areas. The 2003 Chinese Second Arctic Research Expedition experienced the transition of the stratosphereic circulation from a warm anticyclone to a cold cyclone during the ending period of Arctic summertime, a typical establishing process of the polar vortex circulation. The impact of the polar vortex variation on the low-level circulation has been investigated by some scientists through studying the coupling mechanisms of the stratosphere and troposphere. The impact of the Stratospheric Sudden Warming (SFW) events on the polar vortex variation was drawing people's great attention in the fifties of the last century. The Arctic Oscillation (AO) , relating to the variation of the Arctic vortex, has been used to study the impact of the Arctic vortex on climate change. The recent Arctic vortex studies are simply reviewed and some discussions on the Arctic vertex are given in the paper. Some different views and questions are also discussed.

  5. Allergy and sensitization during childhood associated with prenatal and lactational exposure to marine pollutants

    DEFF Research Database (Denmark)

    Grandjean, Philippe; Poulsen, Lars K; Heilmann, Carsten;

    2010-01-01

    Breast-feeding may affect the risk of developing allergy during childhood and may also cause exposure to immunotoxicants, such as polychlorinated biphenyls (PCBs), which are of concern as marine pollutants in the Faroe Islands and the Arctic region.......Breast-feeding may affect the risk of developing allergy during childhood and may also cause exposure to immunotoxicants, such as polychlorinated biphenyls (PCBs), which are of concern as marine pollutants in the Faroe Islands and the Arctic region....

  6. First record of eocene bony fishes and crocodyliforms from Canada's Western Arctic.

    Directory of Open Access Journals (Sweden)

    Jaelyn J Eberle

    Full Text Available BACKGROUND: Discovery of Eocene non-marine vertebrates, including crocodylians, turtles, bony fishes, and mammals in Canada's High Arctic was a critical paleontological contribution of the last century because it indicated that this region of the Arctic had been mild, temperate, and ice-free during the early - middle Eocene (∼53-50 Ma, despite being well above the Arctic Circle. To date, these discoveries have been restricted to Canada's easternmost Arctic - Ellesmere and Axel Heiberg Islands (Nunavut. Although temporally correlative strata crop out over 1,000 km west, on Canada's westernmost Arctic Island - Banks Island, Northwest Territories - they have been interpreted as predominantly marine. We document the first Eocene bony fish and crocodyliform fossils from Banks Island. PRINCIPAL FINDINGS: We describe fossils of bony fishes, including lepisosteid (Atractosteus, esocid (pike, and amiid, and a crocodyliform, from lower - middle Eocene strata of the Cyclic Member, Eureka Sound Formation within Aulavik National Park (∼76°N. paleolat.. Palynology suggests the sediments are late early to middle Eocene in age, and likely spanned the Early Eocene Climatic Optimum (EECO. CONCLUSIONS/SIGNIFICANCE: These fossils extend the geographic range of Eocene Arctic lepisosteids, esocids, amiids, and crocodyliforms west by approximately 40° of longitude or ∼1100 km. The low diversity bony fish fauna, at least at the family level, is essentially identical on Ellesmere and Banks Islands, suggesting a pan-High Arctic bony fish fauna of relatively basal groups around the margin of the Eocene Arctic Ocean. From a paleoclimatic perspective, presence of a crocodyliform, gar and amiid fishes on northern Banks provides further evidence that mild, year-round temperatures extended across the Canadian Arctic during early - middle Eocene time. Additionally, the Banks Island crocodyliform is consistent with the phylogenetic hypothesis of a Paleogene divergence

  7. Evaluating pyrene toxicity on Arctic key copepod species Calanus hyperboreus

    DEFF Research Database (Denmark)

    Nørregaard, Rasmus Dyrmose; Nielsen, Torkel Gissel; Friis Møller, Eva;

    2014-01-01

    Calanus hyperboreus is a key species in the Arctic regions because of its abundance and role in the Arctic food web. Exploitation of the off shore oil reserves along Western Greenland is expected in the near future, and it is important to evaluate the acute and chronic effects of oil emissions...... to the ecosystem. In this study C. hyperboreus females were exposed to concentrations of 0, 0.1, 1, 10 and 100 nM pyrene and saturated concentrations measured to ~300 nM. Daily quantification of egg and faecal pellet production showed significant decreases in the pellet production, while the egg production...

  8. 75 FR 25729 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Science.gov (United States)