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| Author | Hilmer, M | ||||
| Title | A model study of Arctic sea ice variability | Type | Book Whole | ||
| Year | 2001 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | 157 pp | ||
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| Corporate Author | Thesis | Doctoral thesis | |||
| Publisher | Inst Meereskunde | Place of Publication | Kiel | Editor | |
| Language | English | Summary Language | English; German | Original Title | |
| Series Editor | Series Title | Berichte aus dem Institut für Meereskunde an der Christian-Albrechts-Universität Kiel | Abbreviated Series Title | Ber Inst Meereskd Christian-Albrechts-Univ Kiel | |
Series Volume  |
320 | Series Issue | Edition | ||
| ISSN | 0341-8561 | ISBN | Medium | pp | |
| Area | Arctic Ocean | Expedition | Conference | ||
| Notes | Approved | yes | |||
| Call Number | refbase @ user @ 468 | Serial | 2 | ||
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| Author | Gerland, S; Winther, J-G; Örbæk, JB; Ivanov, BV | ||||
| Title | Physical properties, spectral reflectance and thickness development of first year fast ice in Kongsfjorden, Svalbard | Type | Book Chapter | ||
| Year | 1999 | Publication | Proceedings of the International Symposium on Polar Aspects of Global Change | Abbreviated Journal | |
| Volume | Issue | Pages | 275-282 | ||
| Keywords | Fast ice; Ice properties; Reflectance; Ice thickness; Physical properties; PNE, Norway, Svalbard, Kongsfjorden | ||||
| Abstract | A ground truth study was performed on first year fast ice in Kongsfjorden, Svalbard, during spring 1997 and 1998. The survey included sea ice thickness monitoring as well as observation of surface albedo, attenuation of optical radiation in the ice, physical properties and texture of snow and sea ice. The average total sea ice thickness in May was about 0.9 m, including a 0.2 m thick snow layer on top. Within a few weeks in both years, the snow melted almost completely, whereas the ice thickness decreased by not more than 0.05 m. During spring, the lower part of the snow refroze into a solid layer. The sea ice became more porous. Temperatures in the sea ice increased and the measurable salinity of the sea ice decreased with time. Due to snow cover thinning and snow grain growth, maximum surface albedo decreased from 0.96 to 0.74. Texture analysis on cores showed columnar ice with large crystals (max. crystal length > 0.1 m) below a 0.11 m thick mixed surface layer of granular ice with smaller crystals. In both years, we observed sea ice algae at the bottom part of the ice. This layer has a significant effect on the radiation transmissivity. | ||||
| Address | Norwegian Polar Institute, Polar Environmental Centre, N-9296 Tromsoe, Norway | ||||
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| Publisher | Norsk Polarinstitutt | Place of Publication | Editor | ||
| Language | English | Summary Language | English | Original Title | |
| Series Editor | Series Title | Polar Research | Abbreviated Series Title | Polar Res | |
| Series Volume |
18 | Series Issue | 2 | Edition | |
| ISSN | 0800-0395 | ISBN | Medium | ||
| Area | Expedition | Conference | International Symposium on Polar Aspects of Global Change, Tromso (Norway), 24-28 Aug 1998 | ||
| Notes | Conference | Approved | no | ||
| Call Number | refbase @ user @ 726 | Serial | 6 | ||
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| Author | Chapelle, G; Peck, LS | ||||
| Title | Polar gigantism dictated by oxygen availability | Type | Journal Article | ||
| Year | 1999 | Publication | Nature | Abbreviated Journal | Nature |
| Volume | 399 | Issue | Pages | 114-115 | |
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| Language | English | Summary Language | Original Title | ||
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Series Issue | Edition | |||
| ISSN | 0028-0836 | ISBN | Medium | ||
| Area | Black Sea; Caspian Sea; Lake Baikal | Expedition | Conference | ||
| Notes | Approved | no | |||
| Call Number | refbase @ user @ 137 | Serial | 1 | ||
| Permanent link to this record | |||||
| Author | Hobson, KA; Ambrose Jr, WG; Renaud, PE | ||||
| Title | Sources of primary production, benthic-pelagic coupling, and trophic relationships within the Northeast Water Polynya: Insights from δ13C and δ15N analysis | Type | Journal Article | ||
| Year | 1995 | Publication | Marine Ecology Progress Series | Abbreviated Journal | Mar Ecol Prog Ser |
| Volume | 128 | Issue | 1-3 | Pages | 1-10 |
| Keywords | phytobenthos; polynyas; carbon 13; nitrogen isotopes; food webs; check lists; trophic structure; Algae; PNE, Greenland, Northeast Water Polynya | ||||
| Abstract | We used stable carbon (13C/12C) and nitrogen (15N/14N) isotope analysis to investigate linkages between sources of primary production and the pelagic and benthic components of the Northeast Water (NEW) Polynya off northeastern Greenland. Ice algae was enriched in 13C (mean δ13C = -18.6 vs -27.9 ppt) and 15N (mean δ15N = 8.3 vs 4.9 ppt) over particulate organic matter (POM) suggesting that the relative importance of these sources might be traced isotopically. Most grazing crustaceans and filter-feeding bivalves had δ13C and δ15N values in the range of -21 to -23 ppt and 7 to 9 ppt, respectively, indicating a direct pathway from POM. Close benthic-pelagic coupling was also confirmed for other benthic organisms examined with the exception of the predatory or deposit feeding echinoderms Ophiocten, Ophiacantha and Pontaster. Compared with other Arctic and temperate marine food webs, stable-carbon isotope values for the NEW Polynya were depleted in 13C. A δ15N trophic model that incorporated taxon-specific isotopic fractionation factors indicated that the NEW Polynya consisted of 4.5 to 5 trophic levels. Stable-isotope analysis may be well suited to establishing the importance of polynyas as sites of high primary productivity and tight benthic-pelagic coupling relative to regions of more permanent ice cover. |
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| Address | Canadian Wildlife Service, 115 Perimeter Road, Saskatoon, SK S7N 0X4, Canada | ||||
| Corporate Author | Thesis | ||||
| Publisher | Inter-Research | Place of Publication | Oldendorf/Luhe | Editor | |
| Language | English | Summary Language | English | Original Title | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume |
Series Issue | Edition | |||
| ISSN | 0171-8630 | ISBN | Medium | ||
| Area | Northeast Water Polynya; Northeast Greenland Shelf; Arctic | Expedition | Conference | ||
| Notes | Bibliogr.: 63 ref. | Approved | no | ||
| Call Number | refbase @ user @ 133 | Serial | 3 | ||
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| Author | Aberle, N; Witte, U | ||||
| Title | Deep-sea macrofauna exposed to a simulated sedimentation event in the abyssal NE Atlantic: in situ pulse-chase experiments using 13C-labelled phytodetritus | Type | Journal Article | ||
| Year | 2003 | Publication | Marine Ecology Progress Series | Abbreviated Journal | Mar Ecol Prog Ser |
| Volume | 251 | Issue | Pages | 37-47 | |
| Keywords | Deep-sea; Pulse-chase experiment; δ13C; Benthic carbon remineralisation; Macrofauna; Atlantic Ocean, Porcupine Abyssal Plain | ||||
| Abstract | Tracer experiments with 13C-labelled diatoms Thalassiosira rotula (Bacillariophycea, 98% 13C-labelled) were conducted at the Porcupine Abyssal Plain (PAP) in the NE Atlantic (BENGAL Station; 48°50'N, 16°30'W, 4850 m depth) during May/June 2000. In situ enrichment experiments were carried out using de ep-sea benthic chamber landers: within the chambers a spring bloom was simulated and the fate of this food-pulse within the abyssal macrobenthic community was followed. In focus was the role of different macrofauna taxa and their vertical distribution within the sediment column in consuming and reworking the freshly deposited material. T. rotula is one of the most abundant pelagic diatoms in the NE Atlantic and therefore 0.2 g of freeze dried T. rotula, equivalent to 1 g algal C m-2 yr-1, was injected into each incubation chamber. Three different incubation times of 2.5, 8 and 23 d were chosen in order to follow the uptake of 13C-labelled phytodetritus by macrofauna. After only 2.5 d, 77% of all macrofauna organisms showed tracer uptake. After 23 d the highest degree of enrichment was measured and 95% of the individuals had taken up 13C from the introduced algal material. In addition to that a downward transport of organic matter was observed, even though the mixing was not very intense. The initial processing of carbon was dominated by polychaetes that made up a percentage of 52% of total macrofauna. In general macrofauna organisms that lived close to the sediment surface had higher access to the simulated food-pulse, confirming the hypothesis that individuals close to the sediment surface have the strongest impact on the decomposition of phytodetritus. In our study we observed only modest vertical entrainment of 13C tracers into the sediment. With regard to contradictory results from former 13C-enrichment experiments in bathyal regions, compared to results from our study site in the abyssal plain, we thus propose pronounced differences in feeding strategies between macrofauna communities from continental margins and abyssal plains. |
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| Address | Aberle, Witte: Max Planck Institute for Marine Microbiology, Celsiusstr. 1, 28359 Bremen, Germany; Aberle: Present address: Max Planck Institute for Limnology, August-Thienemann-Str. 2, 24306 Plön, Germany; Email: aberle@mpil-ploen.mpg.de | ||||
| Corporate Author | Thesis | ||||
| Publisher | Inter-Research | Place of Publication | Oldendorf/Luhe | Editor | |
| Language | English | Summary Language | English | Original Title | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume |
Series Issue | Edition | |||
| ISSN | 0171-8630 | ISBN | Medium | ||
| Area | NE Atlantic | Expedition | Conference | ||
| Notes | Approved | no | |||
| Call Number | refbase @ user @ 706 | Serial | 4 | ||
| Permanent link to this record | |||||