A search of the ASTIS database for "SISN 76644/76661" has found the following 18 records, which are sorted in descending order of year.
Migration phenology of beluga whales in a changing Arctic / Bailleul, F. Lesage, V. Power, M. Doidge, D.W. Hammill, M.O.
(Climate research, v. 53, no. 3, 2012, p. 169-178, ill., maps)
ASTIS record 76658.
Global warming has been linked to dramatic environmental changes, particularly in polar marine environments, where water temperatures and sea-ice cover are especially affected. Using satellite telemetry, we investigated how local changes in sea-surface temperatures (2002-2004) affected the movement patterns of belugas, Delphinapterus leucas, in eastern Hudson Bay (EHB), Canada. Of 26 whales equipped with satellite transmitters, 17 had records that extended beyond the summer season and showed a fall migration pattern. During summer, foraging activity of individuals was either aggregated, at small spatial scales of <90 km (Strategy A), or dispersed, at larger spatial scales of >120 km (Strategy D). In 2002 and 2003, belugas preferentially selected cold water temperatures <4°C, while, in 2004, no selection occurred. In 2002-2003, the range of water temperatures was larger than in 2004. Moreover, while cold waters were found mainly to the north of the Belcher Islands in 2002-2003, cold waters were broadly scattered throughout the whole bay in 2004. Independent of year, animals employing Strategy A left their summer habitat late (31 October, ±14 d), while those using Strategy D left about 3 wk earlier (4 October, ±2 d). In 2002-2003, the range of water temperatures was larger than in 2004. Moreover, while cold waters were found mainly to the north of the Belcher Islands in 2002-2003, cold waters were broadly scattered throughout the whole bay in 2004. Therefore, it appeared that the strategy used in summer, and hence the migration timing among EHB belugas, was related to sea-surface temperature conditions. Although other factors may also trigger migration, the present study is among the first to reveal a relationship between environmental conditions and habitat use and the migration patterns of beluga whales. Consequently, this work indicates alterations in a well-established migration phenology due to longer term effects of climate change on this Arctic species. (Au)
I, J, D, G, E
Animal behaviour; Animal distribution; Animal food; Animal live-capture; Animal migration; Animal population; Animal tagging; Bathymetry; Beluga whales; Bioclimatology; Climate change; Diving (Animals); Marine ecology; Ocean temperature; Satellite communications; Sea ice; Seasonal variations; Temporal variations; Underwater acoustic telemetry; Wildlife habitat
Belcher Islands waters, Nunavut; Hudson Bay
Exposure to toxic metals and persistent organic pollutants in Inuit children attending childcare centers in Nunavik, Canada / Turgeon O'Brien, H. Blanchet, R. Gagné, D. Lauzière, J. Vézina, C. Vaissière, É. Ayotte, P. Déry, S.
(Environmental science & technology, v. 46, no. 8, Apr. 17, 2012, p.4614-4623, ill.)
ASTIS record 76657.
Arctic populations are exposed to substantial levels of environmental contaminants that can negatively affect children's health and development. Moreover, emerging contaminants have never been assessed in Inuit children. In this study, we document the biological exposure to toxic metals and legacy and emerging persistent organic pollutants (POPs) of 155 Inuit children (mean age 25.2 months) attending childcare centers in Nunavik. Blood samples were analyzed to determine concentrations of mercury, lead, polychlorinated biphenyls (PCBs), pesticides, brominated flame retardants [e.g., polybrominated diphenyl ethers (PBDEs)] and perfluoroalkyl and polyfluoroalkyl substances [PFASs; e.g. perfluorooctanesulfonate (PFOS) and perfluorooctane (PFOA)]. Lead [geometric mean (GM) 0.08 µmol/L], PCB-153 (GM 22.2 ng/g of lipid), BDE-47 (GM 184 ng/g of lipid), PFOS (GM 3369 ng/L), and PFOA (GM 1617 ng/L) were detected in all samples. Mercury (GM 9.8 nmol/L) was detected in nearly all blood samples (97%). Levels of metals and legacy POPs are consistent with the decreasing trend observed in Nunavik and in the Arctic. PBDE levels were higher than those observed in many children and adolescents around the world but lower than those reported in some U.S. cities. PFOS were present in lower concentrations than in Nunavimmiut adults. There is a clear need for continued biomonitoring of blood contaminant levels in this population, particularly for PBDEs and PFASs. (Au)
T, K, J
Age; Biological sampling; Blood; Capacity building; Children; Chlordanes; Chromatography; Day care; DDT; Detection; Effects monitoring; Food; HCH; Health; Heavy metals; Inuit; Lead; Mass spectrometry; Measurement; Mercury; Milk; Organobromines; Organofluorines; PCBs; Pesticides; Pollution; POPs; Public participation; Risk assessment; Social surveys; Temporal variations; Toxaphene; Toxicity; Women
Traditional food consumption is associated with higher nutrient intakes in Inuit children attending childcare centres in Nunavik / Gagné, D. Blanchet, R. Lauzière, J. Vaissière, É. Vézina, C. Ayotte, P. Déry, S. Turgeon O'Brien, H.
(International journal of circumpolar health, v. 71, 18401, 2012, 9 p., ill.)
ASTIS record 76656.
Libraries: ACU MWM
Objectives. To describe traditional food (TF) consumption and to evaluate its impact on nutrient intakes of preschool Inuit children from Nunavik. Design. A cross-sectional study. Methods. Dietary intakes of children were assessed with a single 24-hour recall (n=217). TF consumption at home and at the childcare centres was compared. Differences in children's nutrient intakes when consuming or not consuming at least 1 TF item were examined using ANCOVA. Results. A total of 245 children attending childcare centres in 10 communities of Nunavik were recruited between 2006 and 2010. The children's mean age was 25.0±9.6 months (11-54 months). Thirty-six percent of children had consumed at least 1 TF item on the day of the recall. TF contributed to 2.6% of total energy intake. Caribou and Arctic char were the most reported TF species. Land animals and fish/shellfish were the main contributors to energy intake from TF (38 and 33%, respectively). In spite of a low TF intake, children who consumed TF had significantly (p<0.05) higher intakes of protein, omega-3 fatty acids, iron, phosphorus, zinc, copper, selenium, niacin, pantothenic acid, riboflavin, and vitamin B12, and lower intakes of energy and carbohydrate compared with non-consumers. There was no significant difference in any of the socio-economic variables between children who consumed TF and those who did not. Conclusion. Although TF was not eaten much, it contributed significantly to the nutrient intakes of children. Consumption of TF should be encouraged as it provides many nutritional, economic, and sociocultural benefits. (Au)
T, K, N
Animals; Arctic char; Berries; Carbohydrates; Caribou; Children; Day care; Fats; Fatty acids; Food; Food preparation; Health; Inuit; Obesity; Proteins; Social change; Social surveys; Subsistence
Landscape-scale N mineralization and greenhouse gas emissions in Canadian cryosols / Paré, M.C. Bedad-Haughn, A.
(Geoderma, v.189-190, Nov. 2012, p. 469-479, ill.)
ASTIS record 76653.
Arctic soils store great amounts of soil organic matter (SOM) that are likely to be affected by future climate changes. Knowledge of the ability of the soil to mineralize nitrogen (N) and release greenhouse gases (GHG) at the landscape scale is critical to predict and model future effects of climate change on Arctic SOM. The objective of this study was to investigate how soil gross N mineralization and GHG emissions vary across landscapes and Arctic ecosystems. This study was conducted in three Arctic ecosystems: Sub-Arctic (Churchill, MB), Low-Arctic (Daring Lake, NWT), and High-Arctic (Truelove Lowlands, NU). The topography was divided into five landform units: 1) upper (Up), 2) back (Back), and 3) lower (Low) slopes for catena sites and 4) hummock and 5) interhummock for hummocky sites (i.e., hummock in Churchill and ice-wedge polygons in Truelove). All sites were sampled near the end of their growing seasons (i.e., from two to three weeks before plant senescence). Soil gross N mineralization was measured in situ using a 15N dilution technique, whereas soil GHG emissions (N2O, CH4, and CO2) were measured in situ using a multicomponent Fourier transform infrared gas analyzer combined with an automated dark chamber. For all ecosystems, topography significantly influenced soil gross N mineralization and CO2 emissions. Topography had no significant impact on N2O and CH4 fluxes most likely because net fluxes were extremely low throughout landscapes. Soil gross N mineralization and CO2 emissions increased from Up, Back, to Low and from hummock to interhummock landform units. For example, at Churchill, soil gross mineralization rates averaged 4 mg N-NH4+/kg/d in upper slopes and progressively increased to about 25 mg N-NH4+/kg/d in the lower slopes. Similarly, CO2 emission rates at Daring Lake averaged 0.5 µmol CO2/m²/s in upper slopes and progressively increased to about 2.3 µmol CO2 m²/s in the lower slopes. Comparisons among ecosystems showed that Churchill (Sub-Arctic) had the highest gross N mineralization rates followed by Truelove (High-Arctic) and Daring Lake (Low-Arctic). Furthermore, Daring Lake had significantly higher CO2 emissions than Churchill and no difference in CH4 and N2O emissions between both ecosystems was found. These findings suggest that all factors influencing C and N cycling processes such as climate and human induced changes may not have similar effects across landscapes or across Arctic ecosystems. (Au)
C, A, E, H
Atmospheric circulation; Bryophytes; Carbon; Carbon cycling; Climate change; Hummocks; Lichens; Mosses; Nitrogen; Nitrogen cycling; Nitrogen oxides; Plant cover; Plant distribution; Plant nutrition; Precipitation (Meteorology); Shrubs; Slopes; Soil chemistry; Soil moisture; Topography; Tundra ecology
G0813, G0826, G0812
Churchill region, Manitoba; Daring Lake region, N.W.T.; Truelove Lowland, Nunavut
Summer melt rates on Penny Ice Cap, Baffin Island : past and recent trends and implications for regional climate / Zdanowicz, C. Smetny-Sowa, A. Fisher, D. Schaffer, N. Copland, L. Eley, J. Dupont, F.
(Journal of geophysical research, v.117, F02006, 2012, 21 p., ill., maps)
This is contribution 20110335 from Natural Resources Canada, Earth Science Sector.
ASTIS record 76651.
At latitude 67°N, Penny Ice Cap on Baffin Island is the southernmost large ice cap in the Canadian Arctic, yet its past and recent evolution is poorly documented. Here we present a synthesis of climatological observations, mass balance measurements and proxy climate data from cores drilled on the ice cap over the past six decades (1953 to 2011). We find that starting in the 1980s, Penny Ice Cap entered a phase of enhanced melt rates related to rising summer and winter air temperatures across the eastern Arctic. Presently, 70 to 100% (volume) of the annual accumulation at the ice cap summit is in the form of refrozen meltwater. Recent surface melt rates are found to be comparable to those last experienced more than 3000 years ago. Enhanced surface melt, water percolation and refreezing have led to a downward transfer of latent heat that raised the subsurface firn temperature by 10°C (at 10 m depth) since the mid-1990s. This process may accelerate further mass loss of the ice cap by pre-conditioning the firn for the ensuing melt season. Recent warming in the Baffin region has been larger in winter but more regular in summer, and observations on Penny Ice Cap suggest that it was relatively uniform over the 2000-m altitude range of the ice cap. Our findings are consistent with trends in glacier mass loss in the Canadian High Arctic and regional sea-ice cover reduction, reinforcing the view that the Arctic appears to be reverting back to a thermal state not seen in millennia. (Au)
B, E, F, J, G
Atmospheric temperature; Boreholes; Climate change; Cores; Density; Effects of climate on ice; Firn; Glaciers; Heat transmission; Ice caps; Ice cover; Mass balance; Mathematical models; Measurement; Melting; Optical properties; Palaeoclimatology; Passive microwave remote sensing; Pyroclastics; Radioactive dating; Recent epoch; Satellites; Sea ice; Seasonal variations; Snow; Snow metamorphism; Stratigraphy; Temperature; Temporal variations; Thermal regimes
Penny Ice Cap, Nunavut
Is mother condition related to offspring condition in migratory caribou (Rangifer tarandus) at calving and weaning? / Taillon, J. Brodeur, V. Festa-Bianchet, M. Côté, S.D.
(Canadian journal of zoology, v. 90, no. 3, Mar. 2012, p. 393-402, ill.)
ASTIS record 76649.
Maternal characteristics can affect offspring traits, yet they are seldom included when considering density dependence of juvenile traits and population dynamics. We quantified the influence of population size and maternal traits on body condition of migratory caribou (Rangifer tarandus (L., 1758)) calves at birth and weaning. We contrasted female-calf pairs of the Rivière-George (RG) herd, which has recently declined to low population size, with pairs of the much larger Rivière-aux-Feuilles (RAF) herd. Calves of the RAF herd were lighter, smaller, and leaner than calves of the RG herd at both birth and weaning. Differences between herds, however, were much greater at weaning than at calving, suggesting a combined effect of herd size and summer range conditions on calf growth. Maternal mass was positively related to calf body condition during both periods. The positive influence of maternal mass on calf body condition was greater for RAF than RG calves at birth, but it was similar for the two herds at weaning. Our results show that the negative effect of population size on calf body condition can be modulated by maternal mass at calving, and that the positive effect of maternal mass is greater at weaning. (Au)
Animal behaviour; Animal health; Animal migration; Animal population; Animal reproduction; Caribou; Seasonal variations; Temporal variations
George, Rivière, region, Québec; Nunatsiavut, Labrador; Ungava, Péninsule d', Québec
Correlates of vitamin D status in Inuit preschoolers and adults and correlates of bone mineral density in Inuit preschoolers / El Hayek, J. Weiler, H. [Supervisor] Egeland, G. [Supervisor]
Montréal : McGill University, 2011.
xxvi, 187 p. : ill., map ; 28 cm.
(ProQuest Dissertations & Theses publication, no. NR78627)
Indexed from a PDF file acquired from ProQuest Dissertations & Theses.
A PDF file has been made available on the Web by McGill University.
Theses (Ph.D.) - McGill University, Montréal, 2011.
ASTIS record 72049 describes chapter 4 as published in a separate manuscript.
ASTIS record 76661.
Libraries: ACU OONL QMM
Evidence since the Nutrition Canada Survey (1973) suggests that Aboriginal people have low intakes of vitamin D and are shifting away from the consumption of traditional foods (TF). Further risk factors including higher body mass index (BMI), ethnicity, and latitude status predispose Aboriginal populations to low vitamin D status. In addition, previous studies suggest that Aboriginal children, as a group, are at a higher risk for low bone mass compared to other Canadian infants as a function of vitamin D. Thus, the objectives of this thesis were to: (i) determine the prevalence of vitamin D deficiency, insufficiency and optimal concentrations in Inuit adults and preschoolers; (ii) identify contributors to vitamin D intake, including market foods (MF) and TF among Inuit adults and preschoolers and compare usual vitamin D intakes to the recommended adequate intake (AI) in Inuit adults and preschoolers; (iii) identify predictors of an optimal vitamin D status in Inuit adults and preschoolers; and (iv) identify predictors associated with a higher bone mineral density (BMD) in Inuit preschoolers. Data for this study were obtained from the 2007-2008 Inuit Health Survey (IHS), which included 2595 adults (>= 18 years (y)) and from the Child Inuit Health Survey (CIHS), which included 388 preschoolers (3 to 5 y) who were randomly selected. For objective (i), plasma or serum 25-hydroxy vitamin D (25(OH)D) was measured by Chemiluminesent technology (DiaSorin, Liaison). For objective (ii), usual intakes of adults were estimated by using information on within person variability obtained from a previous study. Vitamin D intake of preschoolers was adjusted using a second 24 hour dietary recall (24 h recall) and an estimation of the adjusted vitamin D intake was calculated following the guidelines by the Institute of Medicine. For objective (iii) and (iv), logistic regression was used. Also, for objective (iv), heel BMD was estimated using ultrasound Sahara Sonometer. Results showed that vitamin D status of Inuit preschoolers and adults was low at the end of summer. With the decreasing consumption of TF, 14.1-64.7% of adults and 61.4 of preschoolers met or exceeded the AI for vitamin D. In adults, TF was the major contributor to vitamin D intake, whereas in preschoolers, TF intake was too low to establish links to vitamin D status. However milk was the major contributor to vitamin D intake in this age group. The strongest predictors of an optimal vitamin D status among Inuit adults were older age and healthy waist circumference, while for preschoolers, vitamin D intake above the AI and younger age were the strongest predictors. Finally, the strongest predictors of BMD were higher BMI and MUFA intake plus lower latitude. This is the first assessment of vitamin D status of the Inuit population in 30 y and the first assessment of BMD in Inuit preschoolers. In conclusion, this research has identified a high prevalence of low vitamin D status in Inuit preschoolers and young adults. Since TF was positively associated with vitamin D status, further investigation across different seasons would confirm if these observations are consistent year-round. (Au)
K, T, R, N
Age; Anthropometry; Biological sampling; Blood; Bones; Children; Density; Food; Gender differences; Health; Housing; Inuit; Milk; Native peoples; Nordicity; Obesity; Seasonal variations; Social surveys; Subsistence; Theses; Ultrasound remote sensing; Vitamin D
G0813, G081, G10, G0812, G0827, G0826
Canadian Arctic; Greenland; Inuvialuit Settlement Region, N.W.T./Yukon; Nunatsiavut, Labrador; Nunavik, Québec; Nunavut
Spatial and temporal changes of photosynthetically available radiation, temperature and salinity beneath a variable sea ice cover / Rossnagel, A.L. Barber, D. [Supervisor]
Winnipeg, Man. : University of Manitoba, 2011.
xii, 126 p. : ill., maps ; 28 cm.
Indexed a PDF file from the Web supplied by University of Manitoba.
Thesis (M.Sc.) - University of Manitoba, Winnipeg, Man., 2011.
ASTIS record 76660.
Libraries: ACU OONL
Melt ponds greatly increase the transmission of solar radiation through sea ice relative to snow covered or bare ice. This rise in transmittance has the potential to enhance water column heating and primary production. I examine how spatially variable sea ice surfaces control the under-ice salinity, temperature and photosynthetically active radiation (PAR) and provide estimates of solar heating and primary production during melt. Conductivity, temperature, depth and PAR profiles were measured in the Canadian Arctic under snow covered ice, leads, bare ice and melt ponds. The under-ice light field to a depth of 10 to 13 m was highly variable, controlled by increased transmission under melt ponds and shading by bare ice. Below, the light field became relatively homogeneous showing the depth the surface heterogeneity had an effect on transmitted PAR. Furthermore, one water column profile is not representative of the PAR, salinity or temperature under a spatially heterogeneous surface. (Au)
D, G, F, J, E
Albedo; Chlorophyll; Heat transmission; Ice floes; Light; Mathematical models; Melting; Ocean-atmosphere interaction; Optical properties; Photosynthesis; Primary production (Biology); Puddles; Salinity; Sea ice; Snow cover; Solar radiation; Spatial distribution; Surface properties; Temperature; Theses; Thickness
Amundsen Gulf, N.W.T.; Darnley Bay, N.W.T.; Franklin Bay, N.W.T.
Vulnerability of Inuit women's food system to climate change in the context of multiple socio-economic stresses - a case study from Arviat, Nunavut / Beaumier, M. Ford, J. [Supervisor]
Montréal : McGill University, 2011.
144 p. : ill., maps ; 28 cm.
Thesis (M.A.) - McGill University, Montréal, 2011.
Indexed a PDF file from the Web provided by McGill University.
French abstract provided.
ASTIS record 76659.
Libraries: QMM OONL
Nunavut has the highest incidence of food insecurity in Canada, where 56% of Inuit households are believed to experience difficulties in obtaining sufficient food. Food insecurity occurs when food systems are stressed such that adequate nutrition is not accessible, available, and/or of insufficient quality. Inuit food systems comprising traditional and store food components are affected by economic, social and cultural transformations, and ecological changes, most notably associated with climate change. Inuit women have been identified to be particularly vulnerable to food insecurity, a condition that can be exacerbated by climate change stresses on their food system. This research identifies and characterizes the key factors determining Inuit women's food system vulnerability and adaptability to climate change and human stressors, and the factors contributing to food insecurity. This research was conducted in collaboration with the community of Arviat, Nunavut, using a community-based participatory research approach. Arviat is experiencing a high level of food insecurity, particularly among women. Photovoice, semi-structured interviews with Inuit women (n=42) and key informants (n=8), focus groups with women (n=7), elders (n=3) and hunters (n=2), and participant observations were used to collect in-depth qualitative data. Findings show that Inuit's food system in Arviat is sensitive to climate-related risks and changes, but climate change was not identified as affecting women's food security. Human factors such as financial resources and budgeting skills, store food knowledge, decrease in the transmission of country food knowledge, decrease in traditional training, substance use and gambling and high cost of living, negatively impact Inuit women's food security. On the other hand, a strong sharing network, governmental financial support and local educational initiatives help strengthen the food system and improve food security. (Au)
T, N, E, J, R, K, I
Acclimatization; Adaptability (Psychology); Animal distribution; Animal population; Caribou; Climate change; Costs; Culture (Anthropology); Economic conditions; Elders; Environmental impacts; Food; Food preservation; Gambling; Health; Health care; Hunting; Ice; Inuit; Meteorology; Participatory action research; Prices; Risk assessment; Safety; Social change; Social conditions; Social surveys; Socio-economic effects; Subsistence; Substance abuse; Theses; Traditional knowledge; Trafficability; Women
Some observations of Short-eared Owl, Asio flammeus, ecology on Arctic tundra, Yukon, Canada / Reid, D.G. Doyle, F.I. Kenney, A.J. Krebs, C.J.
(Canadian field-naturalist, v.125, no. 4, Oct.-Dec. 2011, p. 307-315, ill.)
ASTIS record 76655.
We investigated nesting behavior, food habits, and interspecific interactions of Short-eared Owls (Asio flammeus) within an arctic tundra raptor community on Herschel Island and Komakuk Beach, northern Yukon, Canada. Short-eared Owls were the least common nesting raptor. We found only three nests, all on Herschel Island. All nests were on relatively elevated sites with fairly substantial vegetative cover. All nests failed in the egg stage, from a combination of human disturbance and possible predation by Arctic Fox (Vulpes lagopus) or Red Fox (Vulpes vulpes). Short-eared Owls nested only in years when small rodent densities were at least 4 to 5 individuals per hectare in the spring. Short-eared Owls ate Northern Collared Lemmings (Dicrostonyx groenlandicus), Brown Lemmings (Lemmus trimucronatus), and Tundra Voles (Microtus oeconomus) almost exclusively, without clear selectivity. Peregrine Falcons (Falco peregrinus) killed two adult Short-eared Owls. In northern Yukon, the Short-eared Owl remains an uncommon summer resident and uses the region as a migration route. Spring rodent densities and interspecific predation are prominent limiting factors, and human disturbance also limits nesting success. We recommend restricting access to most tundra areas during periods when the birds are mating, initiating nesting, and incubating eggs. We recommend that human infrastructure be designed so that it cannot support novel nesting (and therefore local range expansion) by other nesting raptors that compete with and prey on Short-eared Owls. (Au)
I, J, N
Animal behaviour; Animal food; Animal population; Animal waste products; Biological sampling; Bird nesting; Lemmings; Peregrine Falcons; Plant cover; Predation; Rodentia; Short-eared Owls; Tundra ecology; Voles; Wildlife management
Herschel Island, Yukon; Komakuk Beach, Yukon
Environment, climate and tree growth relationships at the western Canadian Arctic treeline / Sweeney, S.P. Green, S. [Supervisor]
Prince George, B.C. : University of Northern British Columbia, 2011.
ix, 122 p. : ill., maps ; 28 cm.
(ProQuest Dissertations & Theses publication, no. MR75170)
Thesis (M.Sc.) - University of Northern British Columbia, Prince George, B.C., 2011.
Indexed from a PDF file acquired from ProQuest Dissertations & Theses.
ASTIS record 76654.
The latitudinal forest-tundra ecotone is an area that is experiencing substantial changes with respect to tree growth and climate change. We examined the response of radial tree growth to climate in adjacent regions of northern Yukon and Northwest Territories, Canada, across environmental and spatial gradients using dendrochronological methods. Principal components analysis was used to derive the primary modes of variation in the tree-ring records, which were subsequently attributed to environmental and climatic features. We found that slope gradient (small spatial scales) and ecoregional classification (larger spatial scales) played substantial roles in determining the response of tree growth to climate. Climate correlations were found for current and previous years to growth, many of which challenge currently held assumptions regarding the dominant climatic determinants of tree growth at high latitudes. These findings indicate that Arctic forest environments are highly complex, and that expected changes in the biosphere will occur at various rates, times and places. (Au)
H, E, C, J
Bioclimatology; Black spruces; Climate change; Dendrochronology; Effects of climate on plants; Effects of temperature on plants; Growing season; Microclimatology; Plant distribution; Plant growth; Plant-soil relationships; Plant-water relationships; Taiga ecology; Theses; Topography; Treeline; Tundra ecology; White spruces
Arctic Red River region, N.W.T.; Dempster Highway region, N.W.T./Yukon; Inuvik region, N.W.T.; Mackenzie Delta, N.W.T.; Richardson Mountains, N.W.T./Yukon
Activity, diversity and community structure of aerobic methane-oxidizing and carbon dioxide-producing bacteria in soils from the Canadian High Arctic / Martineau, C. Greer, C. [Supervisor] Whyte, L. [Supervisor]
Montreal : McGill University, 2011.
xvii, 140 p. : ill. ; 28 cm.
(ProQuest Dissertations & Theses publication, no. NR77525)
Thesis (Ph.D.) - McGill University, Montreal, Quebec, 2011.
Indexed from a PDF file acquired from ProQuest Dissertations & Theses.
The thesis includes four manuscipts, chapters 3 and 4 have been published and are described in ASTIS records 70376 and 75522, respectively. Chapters 5 and 6 have been submitted for publication.
ASTIS record 76652.
Libraries: OONL QMM
The fate of soil organic carbon stocked in permafrost environments is a major concern in the context of global warming. In this thesis, the bacterial populations implicated in two important aerobic microbially-driven processes of the carbon cycle, aerobic methane oxidation and carbon dioxide production, were studied in different soils from the Canadian high Arctic. A protocol for the safe and sensitive detection of DNA in cesium chloride density gradients for stable isotope probing of DNA, a recent and widely used technique in microbial ecology allowing for the identification of microorganisms implicated in the degradation of a specific substrate, was developed. Using this protocol, active methanotrophic bacteria from the genera Methylobacter and Methylomonas were identified in active layer soils from Eureka, in the Canadian high Arctic. These soils had the capacity to oxidize methane at 4°C and at room temperature (RT), but the oxidation rates were greater at RT and were significantly enhanced by nutrient amendment. Bacterial populations implicated in aerobic methane oxidation and carbon dioxide production were studied in three different soils with highly distinctive physico-chemical characteristics from Axel Heiberg Island, in the Canadian high Arctic. Using microarray and clone library analyses of the particulate methane monooxygenase gene (pmoA), putative atmospheric methane oxidizers from the uncultured genotypes "upland soil cluster gamma" and "upland soil cluster alpha" were detected for the first time in Arctic soils and were associated with near neutral and acidic pH conditions, respectively. The overall methanotrophic bacterial diversity in these soils was higher than previously described for other Arctic soils and the community composition differed depending on the soil type. Potential methane oxidation rates of the soils at low and high methane concentrations were positively correlated to the relative abundance of genotype "upland soil cluster gamma". Differences in the bacterial community structure in the three soils from Axel Heiberg Island were detected at the genera/species levels using microarrays of the 16S rRNA gene and were related to soil pH and seasonal changes. Shifts in community structure were also detected at the phyla/classes levels by real-time PCR (qPCR) of the 16S rRNA gene, with the soil carbon dioxide production rate being positively correlated to the relative abundance of bacterial groups previously described as copiotrophs (Alphaproteobacteria, Bacteroidetes, and Betaproteobacteria). The results from this study indicated that bacterial communities in high Arctic soils play an important role in two aerobic processes of the carbon cycle, methane oxidation and carbon dioxide production. Methanotrophic bacteria and methane oxidation were detected in these soils and might be implicated in the reduction of methane emissions from the melting permafrost in the context of global warming. Beside, the relatively higher abundance of copiotrophic bacterial taxa in high Arctic soils with high organic matter content might lead, upon warming, to a rapid increase in soil carbon dioxide production. Further research is needed to assess the relevance of these findings under in situ conditions in a warming climate. (Au)
C, J, H, E
Active layer; Atmospheric chemistry; Bacteria; Bioassays; Biodegradation; Carbon; Carbon cycling; Carbon dioxide; Climate change; Cold adaptation; Detection; Genetics; Identification; Isotopes; Methane; Microbial ecology; Particulate organic matter; Permafrost; Seasonal variations; Soil chemistry; Soil microorganisms; Soil pH; Soils; Theses
Axel Heiberg Island, Nunavut; Eureka, Nunavut
Polar research, education, outreach and communication during the fourth IPY / Provencher, J. Baeseman, J. Carlson, D. Badhe, R. Bellman, J. Hik, D. Huffman, L. Legg, J. Pauls, M. Pit, M. Shan, S. Timm, K. Ulstein, K. Zicus, S.
Paris : International Council for Science, 2011.
48 p. : ill., map ; 28 cm.
Indexed a PDF file from the Web.
ASTIS record 76650.
Executive Summary: One hundred and twenty-five years after the first International Polar Year (IPY), the fourth IPY (2007-2008) represented the most ambitious polar research programme in history, and included for the first time a full range of physical, biological and social science projects. IPY 2007-2008 set out to engage members of the general public in active polar science endeavours on a global scale. Overall, the education, outreach and communication (EOC) efforts carried out during the latest IPY were successful. With tens of thousands of scientists, and more than 14 million people in 70 countries touched by outreach events, the fourth IPY was the largest and most comprehensive international science programme. Several factors contributed to the overall success of IPY EOC: 1. EOC was integrated into the larger science IPY programme from the beginning. 2. The EOC efforts engaged and involved experts in both science and communication. 3. A central office encouraged and coordinated EOC efforts throughout the IPY. 4. The EOC programme was branded and inclusive. 5. Advocacy maintained EOC momentum throughout the IPY period. 6. Polar issues were timely and topical. Based on their collaborative and successful experiences of EOC during IPY, both the research and outreach communities have developed new expectations for future science programmes. Namely, both research and EOC are integral to science programmes, should be given equal importance, and EOC must be built in from the initial project planning stages. In general the public wants to be involved in the process of science, and scientists need recognition for their EOC efforts. In order to move science EOC beyond simply being produced and delivered to audiences without assessment, formative evaluation needs to become integrated into science outreach programmes. By doing so, ongoing assessment, reflection and adjustment can ensure outreach programmes are effective. Since this approach is different from most current practices, it will require a major reorientation with a number of necessary steps, including the following: Acceptance within the scientific community and from the funding agencies that EOC is an essential component of research projects, and that all people involved (scientists, educators, communicators, public and media) can and should learn from each other. Specific budget items and dedicated trained EOC staff are needed for EOC to be effective. Communication training with educators/communicators needs to be part of the professional development of all scientists. Professional recognition, publication and career advancement opportunities for people doing EOC activities need to become part of the scientific community's expectations. Continued integration of EOC at science conferences, meetings and workshops is needed. Support for EOC networks is needed to ensure continued communication between scientists and outreach projects and partners. Like many science initiatives, IPY relied on the efforts and energy of early career researchers (ECRs) in both research and outreach programmes. Developed in concert with the IPY, the Association of Polar Early Career Scientists (APECS) enhanced the roles early career professionals play in international research and provided opportunities to gain the additional skills needed for successful careers. APECS has been recognized by the IPY sponsors, the International Council of Science (ICSU) and the World Meteorological Organization (WMO), as the organization that, together with other partners (e.g., IASC and SCAR), will carry forward the momentum of polar research, education and outreach in the years to come (ICSU & WMO 2010). The lessons learned from creating APECS can now serve as a model for how other initiatives can include and recruit ECRs in a meaningful and lasting way. A number of factors were imperative to the success of APECS during and beyond IPY: 1. The energy, momentum and desire required for early career programmes to be successful must come from the ECRs themselves. 2. True support from organizations and partners that are willing to engage young researchers is integral to having meaningful involvement for ECRs. 3. Direct involvement of established scientists alongside ECRs is needed to bridge knowledge gaps and develop mentorship programmes. 4. The governance and management of the ECR associations and projects need to be driven by ECRs; they also need to be designed for a quick turnover rate in order to maintain momentum and energy in the face of changing personnel and to assure that ECRs have time to concentrate on their research while being active in leadership roles. 5. Dedicated coordination staff and funding can create a lot of synergies and activities, and are critical for building and maintaining institutional memory. 6. ECR programmes need to offer services and activities that go beyond home institutions and national boundaries to ensure interdisciplinary and international collaborations. Post-IPY APECS continues to grow and expand, and is now an integral and necessary player in shaping both the present and future of polar research. Over the next decade the polar regions will undergo many changes, and polar researchers will be continually challenged as these changes impact the people, infrastructure and ecosystems. It is imperative that ECRs trained during the IPY stay connected to and engaged in polar topics. Continuing to support APECS and providing the infrastructure to retain the skills, knowledge and capacity built during IPY is critical. Without this support, much of the energy and enthusiasm created during the IPY will dissipate and be lost by the polar community and to science and society as a whole. Through the strong EOC component and ECR involvement several practical lessons can be drawn from the experiences of IPY outreach efforts. These lessons are important to consider when designing other science outreach and communication progra mmes: The public, students, teachers, media, artists and musicians want to be actively engaged in science. Professionals in science and communication, at junior and senior levels, expressed frustration at the limited professional recognition for outreach activities. Small-scale outreach projects benefit greatly by being linked to larger outreach initiatives. Formal outreach assessment is still lacking in most programmes and needs to be prioritized in order to gauge the effectiveness of such programmes and to adapt accordingly. In many cases, science EOC has moved beyond the traditional poster or pamphlet, but more needs to be done to ensure that outreach efforts are reaching target audiences. Institutions and organizations with long-term programmes should house and maintain networks that link scientists and communicators, creating legacies and sustaining outreach efforts past short-lived projects. Science outreach efforts should involve partners such as teachers, media and science centers that already have EOC capacity and an audience. Archival capacity for outreach programmes needs to be planned from the beginning to ensure that resources created, such as videos and curricula, are available beyond the projects' lifespan. Multi-year science events are more likely to attract partners for outreach efforts as funding cycles and institutional programming agendas often do not naturally coincide with science planning. With the many challenges facing society today, public outreach and communication can no longer afford to be a low priority within the scientific community. Science outreach efforts must be given an equal standing to research and an important role within scientific programmes to ensure that key audiences such as teachers and professional communicators have the resources and networks to access relevant and current science information. The many lessons learned from the IPY EOC efforts can help inspire science outreach efforts to improve planning, enhance self-evaluation and expand on the current elevated interest in public outreach programmes. (Au)
Archives; Artists; Capacity building; Career aspirations; Communication; Curricula; Education; Expeditions; Higher education; International Polar Year 2007-08; Musicians; Native peoples; Occupational training; Public education campaigns; Public participation; Research; Research organizations; Research personnel; Science; Scientists; Social sciences; Social surveys; Teachers; World Wide Web; Youth
A comparison of TerraSAR-X, RADARSAT-2 and ALOS-PALSAR interferometry for monitoring permafrost environments, case study from Herschel Island, Canada / Short, N. Brisco, B. Couture, N. Pollard, W. Murnaghan, K. Budkewitsch, P.
(Remote sensing of environment, v.115, no. 12, 15 Dec. 2011, p.3491-3506, ill., maps)
EES contribution 20110051.
ASTIS record 76648.
Interferometric synthetic aperture radar (InSAR) data sets from TerraSAR-X, RADARSAT-2 and ALOS-PALSAR are compared for their ability to detect ground movement over the continuous permafrost site of Herschel Island, Yukon Territory, Canada. All three sensors maintain good coherence within a summer season and can be used to create summer displacement products. Stacking is advantageous for the TerraSAR-X and RADARSAT-2 data sets, although mottling, possibly an interaction of the SAR with vegetation, or residual tropospheric noise, is visible, reducing the reliability of the results. RADARSAT-2 and ALOS-PALSAR provide the most promising results with the ability to form one year interval interferograms. PALSAR can also form two and three year interval interferograms. Long interval data sets spanning 2007 to 2010 identify a band of movement of 20 to 30 cm/year along the north-east coast, and a region of movement of up to 5 cm/year near the northern tip of the island. The ability to form long interval displacement products holds the most promise for permafrost monitoring, since long-term trends are of greater interest for permafrost stability than short-term seasonal changes. TerraSAR-X data have the disadvantage that year to year interferograms cannot be formed. InSAR is not the ideal monitoring technique for the large thaw slumps of Herschel Island. Although general areas of instability can be identified, specific slump detection is limited by radar look direction, and the large and abrupt slump movement, often accompanied by disintegration and collapse of slump sections, causes loss of coherence in the InSAR data. Thaw slumps may require a different interferometric approach, such as slump extent mapping from coherence loss, or the installation of corner reflectors and point target techniques. The frequent revisit and high spatial resolution of TerraSAR-X provide the best chance of maintaining coherence over thaw slumps. In general, InSAR is more successful at identifying broad areas of subtle subsidence in gentle relief, areas of terrain instability, possibly due to permafrost thaw or ground ice melt and the removal of water volume, and prior to significant slumping. (Au)
Detection; Effects monitoring; Movement; Numeric databases; Permafrost; Radar; SAR; Satellites; Seasonal variations; Snowmelt; Temporal variations; Thaw flow slides
Herschel Island, Yukon
Cruise tourism and residents in Arctic Canada : development of a resident attitude typology / Stewart, E.J. Dawson, J. Draper, D.
(Journal of hospitality and tourism management, v. 18, no. 1, Apr. 2011, p. 95-106, ill., maps)
ASTIS record 76647.
The Canadian Arctic represents an emerging market in the rapidly evolving polar cruise sector. Since 1984 when cruises began in this region, cruise ship activity has been sporadic, but in 2006 the number of cruises to Nunavut doubled from 11 to 22. This elevated level of growth has persisted with ice strengthened cruise vessels conducting between 23 and 26 separate cruises through Arctic Canada each year from 2007 to 2010. With a warming climate some suggest this trajectory of growth will continue as sea ice diminishes and passages open up. Despite this growth little is known about this burgeoning sector from the perspectives of local residents. Through two community case studies local attitudes toward cruise tourism are positioned in a resident attitude typology. In Cambridge Bay, where cruise tourism is just emerging, resident attitudes were found to gravitate toward the passive-favourable areas of the typology. By contrast, in Pond Inlet, which is one of the most visited cruise destinations in Nunavut, attitudes were more varied with some individuals expressing degrees of resistance. The article suggests that if local people are to become engaged participants in the development of cruise tourism in Nunavut, then it is critical that resident attitudes and aspirations are articulated, respected and acted upon. (Au)
R, T, L
Inuit; Public opinion; Ships; Social surveys; Socio-economic effects; Tourist trade
G0813, G081, G0815
Cambridge Bay (Settlement), Nunavut; Canadian Arctic waters; Northwest Passage; Pond Inlet (Hamlet), Nunavut
Sea ice contribution to the air-sea CO2 exchange in the Arctic and Southern Oceans / Rysgaard, S. Bendtsen, J. Delille, B. Dieckmann, G.S. Glud, R.N. Kennedy, H. Mortensen, J. Papadimitriou, S. Thomas, D.N. Tison, J.-L.
(Tellus, no.63B, no. 5, Nov. 2011, p. 823-830, ill., map)
ASTIS record 76646.
Although salt rejection from sea ice is a key process in deep-water formation in ice-covered seas, the concurrent rejection of CO2 and the subsequent effect on air-sea CO2 exchange have received little attention. We review the mechanisms by which sea ice directly and indirectly controls the air-sea CO2 exchange and use recent measurements of inorganic carbon compounds in bulk sea ice to estimate that oceanic CO2 uptake during the seasonal cycle of sea-ice growth and decay in ice-covered oceanic regions equals almost half of the net atmospheric CO2 uptake in ice-free polar seas. This sea-ice driven CO2 uptake has not been considered so far in estimates of global oceanic CO2 uptake. Net CO2 uptake in sea-ice-covered oceans can be driven by: (1) rejection during sea-ice formation and sinking of CO2-rich brine into intermediate and abyssal oceanic water masses, (2) blocking of air-sea CO2 exchange during winter, and (3) release of CO2-depleted melt water with excess total alkalinity during sea-ice decay and (4) biological CO2 drawdown during primary production in sea ice and surface oceanic waters. (Au)
G, E, J, D
Atmospheric chemistry; Carbon cycling; Carbon dioxide; Chemical oceanography; Formation; Ice cover; Mathematical models; Melting; Ocean currents; Ocean-atmosphere interaction; Polynyas; Primary production (Biology); Salinity; Sea ice; Seasonal variations; Water masses
Antarctic waters; Arctic Ocean
The other sovereignties : Québec and the Arctic / Roussel, S. Payette, J.-F.
(The Arctic is hot, part II / Edited by J.E. Fossum and S. Roussel. International journal (Toronto), v. 66, no. 4, Autumn 2011, p. 939-955)
References as footnotes.
Indexed a PDF file from the Web.
ASTIS record 76645.
Since 2004, the Canadian government has been "rediscovering" the Arctic. The Canadian forces, absent from this region for almost two decades, are now back regularly, conducting exercises or building new infrastructure, while a good deal of the equipment acquisition programs are designed to sustain military operations in the north. The north is prominent in official government discourse, as well as in policy. This discourse emphasizes three interconnected elements. First, the north is "ours," a part of Canadian territory, establishing a clear distinction between "us Canadians" and "others." Second, Canadian soil in the north is under siege, both in terms of sovereignty and security. Other Arctic powers (such as the United States and Russia), non-Arctic powers (such as China), and nonstate actors (private corporations, criminal organizations, and terrorists) are staring at the Canadian north and will exploit any weakness in the Canadian determination to protect it. The list of threats is long and challenging for the Canadian forces. Third, the north is a land of opportunity for new development and resource exploitation, and it is the responsibility of Canadians to harvest the bounty of this territory. One of Prime Minister Stephen Harper's favourite slogans is "use it or lose it"; a phrase he coined in 2007 in relation to Arctic sovereignty. (1) Many reasons could explain this sudden rush to the north in Ottawa, the first possibility being the need to manage the consequences of global warming and to face an anticipated and significant increase in human activity in a region with a great reduction in ice cover. But such motives are not inconsistent with others, such as the instrumentalization of the north for domestic political objectives. These objectives are connected to recurrent themes in Canada's national and external identity, in which the Arctic plays a prominent role. As we will see later, the vast majority of Canadians identify with this region, even if very few of them ever travel to the Arctic. The image of vast, cold, and pure spaces, as well as the presence of indigenous communities, are associated with the history and definition of Canadian national identity, especially since the last quarter of the 20th century. The polar bear and the inukchuk, rather than the beaver, are today Canada's national and international symbols. Official discourse reinforces this characterization of Canadian identity. It paints Canada as an Arctic power or an energy superpower with vast reserves of oil and gas in the north, and implicitly depicts the defence of sovereignty in the region as a counterweight to a deeper North American integration which might weaken or undermine Canada's national identity. (2) From this perspective, these discourses could be conceived as a part of a nation-building effort. ... (Au)
R, T, E, M, N, G
Aboriginal rights; Climate change; Continental shelves; Economic development; Effects of climate on ice; Environmental protection; Foreign relations; Geopolitics; Government; Government relations; Ice cover; Identity; Inuit; Military operations; Native land claims; Native peoples; Natural resource management; Nordicity; Political parties; Public opinion; Self-determination; Sovereignty; Treeline
G08, G081, G0826, G07, G0815, G14
Beaufort Sea; Canada; Hans Island, Greenland/Nunavut; Northwest Passage; Nunavik, Québec; Québec; Russian Federation; United States
A model for inferring dissolved organic carbon (DOC) in lakewater from visible-near-infrared spectroscopy (VNIRS) measures in lake sediment / Rouillard, A. Rosén, P. Douglas, M.S.V. Pienitz, R. Smol, J.P.
(Journal of paleolimnology, v. 46, no. 2, Aug. 2011, p. 187-202, ill., map)
Electronic supplementary material available online (as Appendix 1).
ASTIS record 76644.
We developed an inference model to infer dissolved organic carbon (DOC) in lakewater from lake sediments using visible-near-infrared spectroscopy (VNIRS). The inference model used surface sediment samples collected from 160 Arctic Canada lakes, covering broad latitudinal (60-83°N), longitudinal (71-138°W) and environmental gradients, with a DOC range of 0.6-39.6 mg/L. The model was applied to Holocene lake sediment cores from Sweden [Seukokjaure Lake] and Canada and our inferences are compared to results from previous multiproxy paleolimnological investigations at these two sites. The inferred Swedish and Canadian DOC profiles are compared, respectively, to inferences from a Swedish-based VNIRS-total organic carbon (TOC) model and a Canadian-based diatom-inferred (Di-DOC) model from the same sediment records. The 5-component Partial Least Squares (PLS) model yields a cross-validated (CV) R2 CV = 0.61 and a root mean squared error of prediction (RMSEPCV) = 4.4 mg/L (11% of DOC gradient). The trends inferred for the two lakes were remarkably similar to the VNIRS-TOC and the Di-DOC inferred profiles and consistent with the other paleolimnological proxies, although absolute values differed. Differences in the calibration set gradients and lack of analogous VNIRS signatures in the modern datasets may explain this discrepancy. Our results corroborate previous geographically independent studies on the potential of using VNIRS to reconstruct past trends in lakewater DOC concentrations rapidly. (Au)
B, F, J, H, E
Bottom sediments; Carbon; Carbon cycling; Climate change; Colored dissolved organic matter; Cores; Diatoms; Dissolved organic carbon; Environmental impacts; Infrared radiation; Lakes; Light; Mathematical models; Numeric databases; Optical properties; Palaeobotany; Palaeohydrology; Recent epoch; Spectroscopy
G081, G0812, G13
Canadian Arctic; Slipper Lake, N.W.T.; Sweden
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