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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Development and Testing of a Hydro-Chemical River MixingModel to Investigate Sources of Carbon and Mercury in the Mackenzie River Basin, Canada / Utveckling och testning av en vattenkemisk flodblandning Modell för att undersöka källor av kol och kvicksilver i Mackenzie-flodbassängen, Kanada

Erikson, Torbjörn-Johannes January 2020 (has links)
Mercury, Hg, is found in Arctic biota in alarming quantity, posing a potential health risk for the local population. It is believed that the large Arctic rivers contribute to this. The Mackenzie River annually transports approximately 325 km3 water to the Arctic Ocean, which is ca 10% of the freshwater received. The annual water flow also transports ca 2 ton of Hg. In order to investigate the source of Hg within the Mackenzie River Basin and the path of transport, a hydro-chemical river mixing model is constructed using field data gathered in summer 2018 and publicly available data. However, since the Hg concentration is very low in the river water and it is known that Hg binds very strongly to dissolved organic carbon (DOC) and particulate organic carbon (POC), both DOC and POC are utilized instead as proxies for Hg. The purpose of the model is to allow for estimations to be made of the relative contributions of different sub-basins and effluents to the total outflow of (e.g.) DOC at the mouth of the Mackenzie River, based on limited hydrographic and riverine water quality data. The model was used to estimate the mixing of DOC and POC sources for summer 2018 as an initial test of its performance. It performs adequately as it can estimate the amount of water discharge and DOC/TOC (total organic carbon) load that each node contributes to the Mackenzie River. The results from the model suggest that the contribution of organic carbon from each sub-watershed is not solely dependent on either drainage area size or water discharge; additionally, it appears to be determined by the local environment and geology. Water from catchment areas containing peatlands have high DOC content, and water passing through regions with coal layers have high POC content. The loss of POC towards the end of the model coincides well with the expected deceleration of the water discharge entering the Mackenzie River delta. It is concluded that the model should be useful for the study of Hg origin and transport in the Mackenzie River. Also, it has the potential for being a starting point for a more advanced or predictive model. / Varje år levereras stora mängder kvicksilver till det Arktiska havet. Kvicksilver är ett välkänt miljögift, tungmetall, och har kapaciteten att ackumuleras i näringskedjan.Kring Arktiska havet finns det ett flertal bosättningar där innevånarna får sin näring främst från havet och denna befolkning riskerar att bli påverkad av kvicksilverhalten i deras mat.Mackenziefloden mynnar ut i det Arktiska havet i norra Kanada. Med ett vattenflöde av ca 325 km3 vatten per år och ett avrinningsområde på 1.8 miljoner km2 bidrar Mackenziefloden med ca 10% av färskvattentillförseln till Arktiska havet. Det är också uppskattat att ca 2 ton av kvicksilver transporteras via Mackenziefloden.För att kartlägga flödet och ursprunget av kvicksilver används prover tagna i fält 2018 och allmänt tillgängliga data. Från det konstrueras en modell som kartlägger flödet och ursprung av partikulärt och kemiskt löst kol. Förekomsten av partikulärt och kemiskt löst kol är relaterat till förekomst av kvicksilver och är betydligt enklare att mäta.Tillsammans med data på flödeshastighet, tagna från existerande mätstationer, används provresultaten till att etablera en serie av punkter som kommer att representera de olika delarna av Mackenzieflodens dräneringsområde. På detta sätt kan de olika förgreningarna som mynnar ut i Mackenziefloden observeras var och en för sig, vilket gör det lättare att se vilka områden som tillför partikulärt och kemiskt löst kol och i vilka mängder.Det är föga förvånande att de stora floderna, så som Liardfloden och Peelfloden, är bland de största bidragarna av kol, både partikulärt och kemiskt löst. Nära Mackenzieflodens utlopp kan man se att mängden partikulärt kol i suspension avtar, i samband med att flödeshastigheten minskar och partiklar börjar att fällas ut då floden mynnar ut i deltat.Resultaten i den här studien visar en väldigt hög masstransport (i kg/km2/31d), gentemot tidigare observationer. Detta är dock orsakat av att fältproverna som använts här är tagna under en kort period väldigt nära vårfloden, vilket får de dagliga värdena att se väldigt stora ut. Dessa värden är dock bara aktuella en kortare tid och avtar resten av året.Denna modell utgör en potentiell bas för vidare studie av kol och kvicksilverförekomst i Mackenzieflodens avrinningsområde och eventuellt även för andra floder givet tillgängliga data.
102

Debating the Past and Future: an Analysis of Conflicting Views of History Within the MacKenzie Valley Pipeline Inquiry, 1974-1977

MacRury, Malcolm Hector January 1984 (has links)
Permission from the author to digitize this work is pending. Please contact the ICS library if you would like to view this work.
103

Modélisation hydrogéochimique des grands bassins fluviaux: implications du réchauffement climatique

Beaulieu, Emilie 21 October 2011 (has links) (PDF)
L'altération chimique des surfaces continentales constitue un des puits de carbone à la surface de la Terre qui régule le climat grâce à des mécanismes de rétroactions. L'intensité de l'altération est contrôlée par le climat mais aussi par la lithologie, le couvert végétal, l'hydrologie et la présence d'argiles et d'acides dans les sols. Dans ce travail, une étude à l'échelle globale sur des sites a mis en évidence qu'une augmentation de la concentration en CO2 dans l'atmosphère entraînerait une diminution de l'évapotranspiration grâce à une fermeture partielle des stomates, et une augmentation de l'acidité dans les sols liée à l'accroissement de la productivité des végétaux. Ces changements favoriseraient l'altération chimique des silicates et par conséquent, mèneraient à une augmentation de la consommation en CO2 de 3% par 100 ppmv d'augmentation de la teneur en CO2 dans l'atmosphère. Ensuite, l'étude d'un des plus grands bassins versants situé en milieu arctique, le bassin de la Mackenzie (Canada) a permis de mettre en évidence la forte sensibilité de l'altération chimique à la production d'acide sulfurique. En effet, la prise en compte de la présence de pyrite (minéral sulfuré) sur le bassin conduit à une diminution de la consommation en CO2 moyenne de 56%. Par ailleurs, la consommation en CO2 moyenne de ce bassin pourrait augmenter de 53% entre le climat actuel et une projection climatique pour la fin du siècle.
104

Truth Commissions and Public Inquiries: Addressing Historical Injustices in Established Democracies

Stanton, Kim Pamela 01 September 2010 (has links)
In recent decades, the truth commission has become a mechanism used by states to address historical injustices. However, truth commissions are rarely used in established democracies, where the commission of inquiry model is favoured. I argue that established democracies may be more amenable to addressing historical injustices that continue to divide their populations if they see the truth commission mechanism not as a unique mechanism particular to the transitional justice setting, but as a specialized form of a familiar mechanism, the commission of inquiry. In this framework, truth commissions are distinguished from other commissions of inquiry by their symbolic acknowledgement of historical injustices, and their explicit “social function” to educate the public about those injustices in order to prevent their recurrence. Given that Canada has established a Truth and Reconciliation Commission (TRC) on the Indian Residential Schools legacy, I consider the TRC’s mandate, structure and ability to fulfill its social function, particularly the daunting challenge of engaging the non-indigenous public in its work. I also provide a legal history of a landmark Canadian public inquiry, the Mackenzie Valley Pipeline Inquiry, run by Tom Berger. As his Inquiry demonstrated, with visionary leadership and an effective process, a public inquiry can be a pedagogical tool that promotes social accountability for historical injustices. Conceiving of the truth commission as a form of public inquiry provides a way to consider the transitional justice literature on truth commissions internationally along with the experiences of domestic commissions of inquiry to assemble strategies that may assist the current TRC in its journey.
105

Truth Commissions and Public Inquiries: Addressing Historical Injustices in Established Democracies

Stanton, Kim Pamela 01 September 2010 (has links)
In recent decades, the truth commission has become a mechanism used by states to address historical injustices. However, truth commissions are rarely used in established democracies, where the commission of inquiry model is favoured. I argue that established democracies may be more amenable to addressing historical injustices that continue to divide their populations if they see the truth commission mechanism not as a unique mechanism particular to the transitional justice setting, but as a specialized form of a familiar mechanism, the commission of inquiry. In this framework, truth commissions are distinguished from other commissions of inquiry by their symbolic acknowledgement of historical injustices, and their explicit “social function” to educate the public about those injustices in order to prevent their recurrence. Given that Canada has established a Truth and Reconciliation Commission (TRC) on the Indian Residential Schools legacy, I consider the TRC’s mandate, structure and ability to fulfill its social function, particularly the daunting challenge of engaging the non-indigenous public in its work. I also provide a legal history of a landmark Canadian public inquiry, the Mackenzie Valley Pipeline Inquiry, run by Tom Berger. As his Inquiry demonstrated, with visionary leadership and an effective process, a public inquiry can be a pedagogical tool that promotes social accountability for historical injustices. Conceiving of the truth commission as a form of public inquiry provides a way to consider the transitional justice literature on truth commissions internationally along with the experiences of domestic commissions of inquiry to assemble strategies that may assist the current TRC in its journey.
106

FUELLING A WAR MACHINE: Canadian Foreign Policy in the Sino-Japanese War, 1937-1945

FRANCOEUR, David 08 November 2011 (has links)
The subject of Canada’s policy-making in relation to the Sino-Japanese War (1937-1945) has been neglected for over half a century. Therefore neither the scope of Canada’s official assistance to the Chinese during their War of Resistance against Japan nor the motivations behind this assistance have been fully explained or adequately contextualized. Through research using archival records and other primary and secondary sources, the thesis sheds light on the ways in which Canadians chose to respond to Chinese efforts to secure an ally against Japan. Revealing unscrupulous opportunism on the Canadian side during China’s struggle against Japan, the thesis contributes to a revisionist trend which takes aim at romantic mythology about Canadians’ virtuous role in the Second World War. From 1931 to 1941, the Government of Canada sought to maintain a neutral position regarding Japanese encroachments in China. This was partly to honour a friendship established in the First World War but also to protect Canadian exporters’ valuable sales of strategic minerals to Japan. After the attack on Pearl Harbor, pro-Japanese sympathy among Canadians eroded and trade with Japan became politically untenable. In 1942, already five years after the beginning of full-scale war between Japan and China, the Canadian government began preparations to provide material assistance to the beleaguered Chinese. Increasing dialogue between Mackenzie King and Chiang Kai-shek, especially communications through Chiang’s wife Song Meiling, nurtured a promising friendship despite King’s unwillingness to commit “the lives of white men” to war in China and apparently ensured that several shipments of arms and munitions were provided to Chiang’s armies. As the research reveals, the assistance was motivated by hopes of cultivating “goodwill” in China that would favour Canadian businesses after the war. However, the official decision to assist China against Japan sparked a new controversy. Doubts about China’s postwar political stability gave rise to questions about the danger that Canadian munitions would be used in an imminent Chinese civil war. Such warnings, as it turned out, were merited. A bloody conflict between the Communists and Nationalists would erupt in China shortly after the end of the Second World War, in part waged with Canadian weapons. / Thesis (Master, History) -- Queen's University, 2011-05-05 15:23:06.094
107

The influence of the Mackenzie River Plume on marine larval fish assemblages in the Canadian Beaufort Sea shelf

Wong, Sally 15 September 2011 (has links)
In the Beaufort Sea, freshwater input from the Mackenzie River creates a relatively warm and turbid plume across the coastal shelf region. To determine the effects of the Mackenzie River plume on marine larval fish abundance, distribution and assemblages; this study sampled larval fish by using 500 μm bongo nets and obtaining oceanographic measurements across the plume gradient during July and August of 2007. Three larval fish assemblages were identified within three water masses: the intense plume assemblage was dominated by Pacific herring (Clupea pallasii pallasii), the diffuse plume assemblage was dominated by the sub-family Lumpeninae and the oceanic assemblage was dominated by Arctic cod (Boreogadus saida). Also, results revealed that there were no significant differences in the total larval fish abundances within these water masses. In conclusion, this study suggests that the Mackenzie River plume might be identified as an Ecologically and Biologically Significant Area (EBSA), based on the uniqueness criteria under Canada’s coastal conservation strategy.
108

The influence of the Mackenzie River Plume on marine larval fish assemblages in the Canadian Beaufort Sea shelf

Wong, Sally 15 September 2011 (has links)
In the Beaufort Sea, freshwater input from the Mackenzie River creates a relatively warm and turbid plume across the coastal shelf region. To determine the effects of the Mackenzie River plume on marine larval fish abundance, distribution and assemblages; this study sampled larval fish by using 500 μm bongo nets and obtaining oceanographic measurements across the plume gradient during July and August of 2007. Three larval fish assemblages were identified within three water masses: the intense plume assemblage was dominated by Pacific herring (Clupea pallasii pallasii), the diffuse plume assemblage was dominated by the sub-family Lumpeninae and the oceanic assemblage was dominated by Arctic cod (Boreogadus saida). Also, results revealed that there were no significant differences in the total larval fish abundances within these water masses. In conclusion, this study suggests that the Mackenzie River plume might be identified as an Ecologically and Biologically Significant Area (EBSA), based on the uniqueness criteria under Canada’s coastal conservation strategy.
109

Conferences, Crises, and Treaties: Canadian Foreign Policy and the British ImperialSystem in the 1920s

Roy, Peter C. 05 June 2023 (has links)
No description available.
110

Effet optique de la matière organique dissoute colorée sur la production primaire dans des systèmes d'estuaires nordiques : qualité, quantité et changements climatiques

Retamal, Leira 13 April 2018 (has links)
Dans les régions nordiques, les changements climatiques sur les milieux terrestres auront des conséquences encore peu connues sur les écosystèmes aquatiques. La fonte du pergélisol et le changement de la composition végétale auront pour effets de libérer des concentrations élevées de matière organique allochtone vers les écosystèmes aquatiques. Cette matière organique dissoute colorée (CDOM) joue un rôle majeur dans l'atténuation de l'éclairement subaquatique. Cette étude s'intéresse aux effets optiques de la qualité et de la quantité du CDOM en système estuarien nordique. Le CDOM des systèmes d'estuaires de la Grande Rivière de la Baleine et du fleuve Mackenzie a été caractérisé par absorption et par fluorescence synchrone. Ces analyses ont révélé des différences fondamentales entre ces deux systèmes en terme de qualité et de quantité de CDOM. Cependant, une signature de fluorescence particulière a été mise en évidence pour le CDOM nordique, celle-ci étant plus constante que les propriétés d'absorption du CDOM. L'importance optique du CDOM dans l'atténuation de la radiation solaire a été observée dans le système estuarien du fleuve Mackenzie, rivière reconnue pour l'influence des particules sur l'éclairement subaquatique. Les stratégies pigmentaires, la composition du phytoplancton et la production primaire ont également été mesurés. Le CDOM et la matière particulaire contrôlaient l'éclairement dans le visible (400-700 nm), mais seule le CDOM affectait la radiation ultraviolette (<400 nm). Contrairement à la matière particulaire, l'effet optique du CDOM fluvial était mesurable même au-delà de l'épanchement du fleuve Mackenzie, sur le plateau de la Mer de Beaufort. L'impact d'un accroissement de la concentration de CDOM allochtone sur la production primaire a été mesuré dans le système d'estuaire de la Grande Rivière de la Baleine. Les analyses par modélisation ont montré que les modifications du régime spectral affectent la quantité d'éclairement disponible pour la photosynthèse, la profondeur de la zone euphotique, ainsi que le couplage spectral du phytoplancton. En utilisant l'approche expérimentale, les paramètres photosynthétiques ont été mesurés sous un régime spectral modifié par une concentration accrue de CDOM allochtone. Ceci a permis de démontrer que de hautes concentrations de CDOM contribuent à une réduction significative de la production primaire dans la colonne d'eau.

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