Hydrocarbon measurements have been made on dissolved, suspended particulate and sediment samples ... more Hydrocarbon measurements have been made on dissolved, suspended particulate and sediment samples collected in 1987, 1993 and 1994 from the Mackenzie River delta and shelf and in 1993 from 10 smaller Northwest Territories and Nunavut rivers that drain into the Canadian Archipelago or Hudson's Bay. Suspended particulate samples from all rivers have a resolved higher alkane pattern with a well-defined odd–even predominance consistent with a major source in terrestrial, vascular plant material. Particulate samples from the 10 smaller rivers have alkane concentrations that are similar to the Mackenzie River during summer, but PAH (polycyclic aromatic hydrocarbon) concentrations are approximately 10 times lower for the parent PAHs and 100 times lower for alkyl PAHs. PAHs on suspended particulate from the Mackenzie River exhibit a uniform composition typical of mature petrogenic sources, while PAHs in the smaller rivers are typical of combustion. The virtual absence of petrogenic PAHs...
... AS Naidu (✉) ´ BP Finney Institute of Marine Science, University of Alaska, Fairbanks, AK 997... more ... AS Naidu (✉) ´ BP Finney Institute of Marine Science, University of Alaska, Fairbanks, AK 99775-1080, USA E-mail: ffsan@uaf.edu Fax: +1-907-4747204 LW Cooper Department of Ecology and Evolutionary Biology, 569 Dabney Hall, University of Tennessee, Knoxville, TN ...
Brief overviews of the Arctic's atmosphere, ice cover, circulation, primary production and s... more Brief overviews of the Arctic's atmosphere, ice cover, circulation, primary production and sediment regime are given to provide a conceptual framework for considering panarctic shelves under scenarios of climate variability. We draw on past 'regional' studies to scale-up to the ...
As a consequence of human activity, the variability and range of environmental conditions is incr... more As a consequence of human activity, the variability and range of environmental conditions is increasing. We review how the interactions between toxic chemicals and environmental change may affect exposure of aquatic organisms to stressful conditions and therefore alter the risk of deleterious impacts. Even in the absence of new inputs of contaminants, changing environmental conditions alters the transport, transformation and distribution of contaminants and their bioavailability. Conversely, some toxic chemicals modify the exposure of aquatic species to other stressors by affecting species distribution, behaviour or habitat. Across Canada there are a number of specific examples where interactions between contaminants and environmental change are probably harming aquatic species. In the Arctic, change in foraging brought on by change in ice regime, is a plausible mechanism to explain the marked recent increase in mercury concentrations in Beaufort Sea beluga whales. On the Pacific co...
Observations of salinity and oxygen isotope composition (δ 18 O) were made for the Beaufort shelf... more Observations of salinity and oxygen isotope composition (δ 18 O) were made for the Beaufort shelf-Mackenzie estuary waters in September 1990, just prior to ice formation, and for both the water column and ice in April-May 1991, at the end of winter. These measurements are ...
Hydrocarbon measurements have been made on dissolved, suspended particulate and sediment samples ... more Hydrocarbon measurements have been made on dissolved, suspended particulate and sediment samples collected in 1987, 1993 and 1994 from the Mackenzie River delta and shelf and in 1993 from 10 smaller Northwest Territories and Nunavut rivers that drain into the Canadian Archipelago or Hudson's Bay. Suspended particulate samples from all rivers have a resolved higher alkane pattern with a well-defined odd–even predominance consistent with a major source in terrestrial, vascular plant material. Particulate samples from the 10 smaller rivers have alkane concentrations that are similar to the Mackenzie River during summer, but PAH (polycyclic aromatic hydrocarbon) concentrations are approximately 10 times lower for the parent PAHs and 100 times lower for alkyl PAHs. PAHs on suspended particulate from the Mackenzie River exhibit a uniform composition typical of mature petrogenic sources, while PAHs in the smaller rivers are typical of combustion. The virtual absence of petrogenic PAHs...
... AS Naidu (✉) ´ BP Finney Institute of Marine Science, University of Alaska, Fairbanks, AK 997... more ... AS Naidu (✉) ´ BP Finney Institute of Marine Science, University of Alaska, Fairbanks, AK 99775-1080, USA E-mail: ffsan@uaf.edu Fax: +1-907-4747204 LW Cooper Department of Ecology and Evolutionary Biology, 569 Dabney Hall, University of Tennessee, Knoxville, TN ...
Brief overviews of the Arctic's atmosphere, ice cover, circulation, primary production and s... more Brief overviews of the Arctic's atmosphere, ice cover, circulation, primary production and sediment regime are given to provide a conceptual framework for considering panarctic shelves under scenarios of climate variability. We draw on past 'regional' studies to scale-up to the ...
As a consequence of human activity, the variability and range of environmental conditions is incr... more As a consequence of human activity, the variability and range of environmental conditions is increasing. We review how the interactions between toxic chemicals and environmental change may affect exposure of aquatic organisms to stressful conditions and therefore alter the risk of deleterious impacts. Even in the absence of new inputs of contaminants, changing environmental conditions alters the transport, transformation and distribution of contaminants and their bioavailability. Conversely, some toxic chemicals modify the exposure of aquatic species to other stressors by affecting species distribution, behaviour or habitat. Across Canada there are a number of specific examples where interactions between contaminants and environmental change are probably harming aquatic species. In the Arctic, change in foraging brought on by change in ice regime, is a plausible mechanism to explain the marked recent increase in mercury concentrations in Beaufort Sea beluga whales. On the Pacific co...
Observations of salinity and oxygen isotope composition (δ 18 O) were made for the Beaufort shelf... more Observations of salinity and oxygen isotope composition (δ 18 O) were made for the Beaufort shelf-Mackenzie estuary waters in September 1990, just prior to ice formation, and for both the water column and ice in April-May 1991, at the end of winter. These measurements are ...
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