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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.
181

Evolution of eclogite facies metamorphism in the St. Cyr Klippe, Yukon-Tanana Terrane, Yukon, Canada

Petrie, Meredith Blair 01 May 2014 (has links)
The St. Cyr klippe hosts well preserved to variably retrogressed eclogites found as sub-meter to hundreds of meter scale lenses within quartzofeldspathic schists in the Yukon-Tanana terrane, Canadian Cordillera. The St. Cyr area consists of structurally imbricated, polydeformed, and polymetamorphosed units of continental arc and oceanic crust. The eclogite-bearing quartzofeldspathic schists form a 30 by 6 kilometer thick, northwest-striking, coherent package. The schists consist of metasediments and felsic intrusives that are intercalated on the tens of meter scale. The presence of phengite and Permian age zircon crystallized under eclogite facies metamorphic conditions indicates that the eclogite was metamorphosed in situ with its quartzofeldspathic host. I investigated the metamorphic evolution of the eclogite-facies rocks in the St. Cyr klippe using isochemical phase equilibrium thermodynamic (pseudosection) modeling. I constructed P-T pseudosections in the system Na2O-K2O-CaO-FeO-O2-MnO-MgO-Al2O3-SiO2-TiO2-H2O for the bulk-rock composition of an eclogite and a host metatonalite. In combination with petrology and mineral compositions, St. Cyr eclogites followed a five-stage clockwise P-T path. Peak pressure conditions for the eclogites and metatonalites reached up to 3.2 GPa, well within the coesite stability field, indicating the eclogites reached ultrahigh-pressure conditions. Decompression during exhumation occurred with a corresponding temperature increase. SHRIMP-RG zircon dating shows that the protolith of the eclogites formed within the Yukon-Tanana terrane during early, continental arc activity, between 364 and 380 Ma, while the metatonalite protolith formed at approximately 334 Ma, during the Little Salmon Cycle of the Klinkit phase of Yukon-Tanana arc activity. Both the eclogites and the metatonalites were then subducted to mantle depths and metamorphosed to ultrahigh-pressure conditions during the late Permian, between 266 and 271 Ma. The results of our study suggest portions of the Yukon-Tanana terrane were subducted to high-pressure and ultrahigh-pressure conditions. This is the first report of ultrahigh-pressure metamorphism in the accreted terranes of the North American Cordillera. Petrological, geochemical, geochronological, and structural relationships link the eclogites at St. Cyr to other eclogite localities in Yukon, indicating the high-pressure assemblages form a larger lithotectonic unit within the Yukon-Tanana terrane.
182

Geological and Precious Metal Evolution at Freegold Mountain, Dawson Range, Yukon

McInnes, Brent Ian Alexander 10 1900 (has links)
<p> Freegold Mountain is part of a northwesterly trending volcanoplutonic arc comprising the eastern portion of the Yukon Crystalline Terrane. Plutonic rocks in the area intrude Paleozoic metasediments and consist of a Late Triassic to Early Cretaceous granodiorite intruded by the Big Creek Syenite dated at 138 ± 10 Ma. A suite of K-rich intrusive volcanic rocks comprise an early period of basalt-andesite-dacite volcanism and a later rhyolitic volcanism dated at 78 ± 6 Ma. Volcanic rocks at Freegold Mountain can be correlated with Mt. Nansen Volcanics.</p> <p> Two sets of fracture planes, oriented at 165/70E and 18/80W, show dextral and sinistral displacement, respectively. Rhyolite dykes and gold-quartz veins predominantly oriented NNE have been emplaced along the 18/80W extensional fracture systems. These fractures may be modelled as high-angle Reidel shears, although evidence indicates that fracture orientations and fault movement have been complicated by changing stress fields from middle Cretaceous to Tertiary time.</p> <p> The gold-bearing quartz veins at Freegold Mountain are high grade, low-tonnage deposits with grades ranging from 0.4 to 1.0 oz/t. Fluid inclusions from the lower portions of the Laforma mine homogenize at 185° C with salinity ranging between 2 and 4.5 wt. % NaCl equivalent. A boiling zone has been detected above the deeper ore where fluid inclusions show extreme ranges in homogenization temperatures (165-430° C) and salinity (4 - 43 wt. % NaCl). Fluid inclusion waters have stable isotopic signatures indicative of meteoric water with 𝛿D = -138 and 𝛿^18O = -18.4. Boiling of the Laforma fluid has caused a shift towards heavier hydrogen and oxygen isotopic values, mineral deposition and appears to enhance gold precipitation over non-boiling zones. Stable isotopic evidence indicates that the paleolatitude of Freegold Mountain during late Cretaceous time was south of the present day Yukon-B.C. border.</p> <p> The Emmons Hill (Dart) prospect is a gold-bearing vein-breccia with a mineral assemblages of barite, stibnite, marcasite, cinnabar, orpiment, Fe and Mn carbonates and chalcedonic silica. Fluid inclusions from these deposits homogenize between 140-185° with salinities of 0-0.5 wt. % NaCl. This property shows marked similarities to acid-sulphate type precious metal deposits in New Zealand and western United States.</p> <p> Large (x to xx Mt) northwesterly trending diatremes appear to be structurally controlled by small transcurrent faults parallel to and coeval with displacement along the Tintina fault. The Antoniuk diatreme (3.7 Mt @ 1.14 g/t Au) consists of heterolithic and monolithic breccias intruded by dacite and rhyolite dykes. Diamond drilling indicates that a large body of fine to medium grained alaskite is present beneath the auriferous breccia. The deposit formed by the explosive escape of volatile components evolved from the retrograde boiling of a silicic magma chamber. Gold mineralization in the breccia is associated with pyrite and arsenopyrite formed at temperatures around 300°C and salinities of about 4.5 wt. % NaCl.</p> / Thesis / Master of Science (MSc)
183

Silver Mineralogy and Modes of Occurrence at the Silver Hart Deposit, South East Yukon.

Ives-Ruyter, Michael January 2023 (has links)
The Silver Hart property is a high grade silver-lead-zinc deposit consisting of polymetallic vein style, manto (carbonate replacement) style, and skarn type mineralization. Host rock consists of calcareous and non-calcareous sediments of the Cassiar Platform, mainly biotite schists, limestone units, and the monzogranite unit of the Cassiar Batholith. Bulk geochemistry shows that silver concentrations are closely related to copper and antimony values, suggesting freibergite, a silver-rich endmember of tetrahedrite, is the dominant silver mineral. EPMA (microprobe) analyses identified 6 silver minerals present; silver-bearing anglesite, freibergite, diaphorite, stephanite, pyrargyrite, and silver substitution in galena. Sulfur isotope analyses of galena gave an average δ34S of 6.9‰ vs VCDT, indicating a mixed mineralizing fluid source. Metal zoning patterns indicates that there is a thermal gradient across the main vein from hottest in the south-west, above the monzogranite intrusion, to coolest in the north-east. Microprobe analyses of freibergite indicates initial ore-forming fluid temperatures were between 250°C - 350°C, with subsequent cooler mineralization fluids of 170°C - 200°C.
184

Physiological and Biochemical Responses of Yukon and Shandong Thellungiella to Water Deficits

Dedrick, Jeff 09 1900 (has links)
<p> Thellungiella salsuginea (also known as T. halophila), is an emerging model species for studies of plant tolerance to osmotic stress. Currently, Thellungiella plants originating from two geographical locations are being developed for research. Yukon Thellungiella is native to the saline and alkaline soils of the Yukon Territory, Canada. The seeds in this study were collected at the Takhini Salt-Flats near Whitehorse, YT, a sub-arctic and semi-arid region. Plants from the Yukon have been proposed to be a suitable species to study plant tolerance to salinity, cold temperatures, and water deficits. Shandong Thellungiella is native to the saline coast of north-eastern China in Shandong Province where the climate is temperate and affected by summer monsoons. This plant has been proposed as an ideal model for the study of salt tolerance mechanisms but is reported to show little drought tolerance.</p> <p> An objective of this study was to compare Yukon and Shandong Thellungiella plants with respect to their ability to withstand water deficits. Plants were grown simultaneously in controlled environment chambers where watering was withheld until plants visibly wilted. Wilting occurred at a leaf relative water (RWC) content of about 50-60% and then turgor was restored by re-watering. In a second experiment plants allowed to wilt and recover once were then subjected to a second wilting and recovery cycle. The third experimental approach tested the survival capacity of plants after experiencing a wilting episode where leaf RWC dropped to about 30%.</p> <p> With the first drought simulation treatment, both Yukon and Shandong plants took about 6 days to wilt when watering was stopped. After re-watering and recovery, the Yukon plants subjected to a second drought episode took almost two days longer to wilt while the similarly treated Shandong plants showed no change in the days taken to wilt. This indicates that Yukon plants show improved tolerance to stress after a single exposure to a water deficit. Yukon plants were also able to grow and complete their life cycle following exposure to severe water deficit treatment whereas Shandong plants died. Measurements of solute potential showed that the Yukon plants re-established turgor at a lower solute potential of -2.06 +/- 0.03 MPa following recovery from a second drought treatment suggesting that this plant can undergo osmotic adjustment. No evidence of osmotic adjustment was observed for Shandong Thellungiella.</p> <p> Gas chromatography/mass spectrometry (GC/MS) was used to identify the metabolites associated with Thellungiella leaves recovering from water deficits relative to those from unstressed, well-watered controls. For comparison, metabolite profiles were also prepared from leaves of plants harvested at a Yukon field site during a dry year (2003) and a year of higher than normal rainfall (2005). The data was analyzed to identify treatment/sample-specific patterns using ANOVA to test for significance among quantitative and qualitative changes for individual metabolites. Significant changes were then subjected to hierarchical cluster analysis (HCA) and principal component analysis (PCA). Using ANOVA and HCA, we were able to identify the most likely metabolite candidates contributing to the superior tolerance of Thellungiella, and their linkages between broad spectrums of metabolites. Using PCA we were able to assign clusters to the individual plant treatments for each plant source, and identify the most important components contributing to these clusters. Of the ca 289 components detected, only a small subset of components underwent statistically significant changes in abundance. Most of the drought-stress related changes were attributed to sugars: hexoses and disaccharides. Sugars accumulating in the more drought-tolerant Yukon plants and in a dry field season included fructose, glucose and galactose. Of the sugar alcohols, only myo-inositol showed patterns of interest in view of its enrichment in tissues showing superior tolerance to low water conditions. Similar patterns were also shown by the organic acid, threonic acid.</p> <p> A complementary approach was used to characterize metabolic traits associated with exposure to cold temperatures. In this study, a higher content of proline and citrate distinguished plants exposed to cold temperatures irrespective of whether the plants were in cabinets or in the field. Proline content, however, did not show drought-responsive accumulation under any drought treatment tested. As such, by comparison with the drought-stress data we can identify possible stress-specific signatures among metabolites undergoing changes. The study of stress-responsive traits could help develop a better understanding of plant systems and their response to specific environmental conditions.</p> / Thesis / Master of Science (MSc)
185

Geochemistry and Noble Gases of Permafrost Groundwater and Ground Ice in Yukon and the Northwest Territories, Canada

Utting, Nicholas C. 11 January 2012 (has links)
In Canada’s western Arctic, perennial discharge from permafrost watersheds is the surface manifestation of active groundwater flow systems, yet understanding the mechanisms of groundwater recharge and flow in periglacial environments remains enigmatic. This thesis addresses questions on how and where groundwater recharge occurs. Watersheds were selected in Yukon (Fishing Branch River at Bear Cave Mountain) and the Northwest Territories at latitudes spanning from continuous to discontinuous permafrost (five tributary rivers to the Mackenzie River from Wrigley to Aklavik). All are characterized by perennial flow with open water in the winter, and discharge from sedimentary formations of karstic carbonates and evaporate rocks. Determinations of groundwater contributions to discharge, mixing, recharge conditions and circulation times were made on the basis of a suite of analytical approaches involving measurements of major dissolved ions, δ18O, δD, δ13CDIC, 3H, noble gases and flow gauging was conducted at some sites. The application of these tracers show that hydrogeological conditions and flow paths in permafrost terrains are surprisingly similar to those of temperate regions. Groundwater recharge was determined to be a mix of annual precipitation with contributions from snowmelt and precipitation. All systems investigated show that groundwaters have recharged through organic soils with elevated PCO2, which suggests that recharge occurs largely during summer when biological activity is high. Noble gas concentrations show that the recharge temperature was between 0 and 6 °C, which, when considered in the context of discharge temperatures, suggests that there is no significant imbalance of energy flux into the subsurface. Groundwater ages were found using the 3H-3He method and were dependent on flow path. By characterizing groundwater and surface water chemistry, the proportion of groundwater was found in numerous water courses. The possible impact of ground ice formation and melting on noble gas concentrations in groundwater was considered. To assess this link, a new method to measure the noble gas composition of ground ice bodies was developed. The method can be used to determine the origin of ice, based on changes in noble gas ratios between ice originating from compaction of snow (e.g. glacier ice) vs. ice originating from freezing of water. No significant fractionation of noble gases during groundwater freezing and ground ice formation was identified. Applied to determination of the origin of ground ice bodies, the method was shown to be both diagnostic of ice origin and un-encumbered by reactivity in the subsurface, which compromises the use of the dominant atmospheric gases (O2 and N2).   Résumé Dans l’Ouest de l'Arctique canadien, la décharge pérenne dans certaines rivières en région de pergélisol est la manifestation en surface d’une circulation d’eau souterraine; cependant la compréhension des mécanismes d’écoulement et de recharge des eaux souterraines en région de pergélisol demeure énigmatique. Cette thèse s’intéresse à la question de savoir comment et où la recharge des eaux souterraines se produit. Des bassins versants ont été choisis au Yukon (Rivière Fishing Branch à Bear Cave Mountain) et dans les Territoire du Nord-Ouest à des latitudes s’étendant du pergélisol discontinu au pergélisol continu (cinq tributaires du Mackenzie entre Wrigley et Aklavik). Toutes ces rivières ont un écoulement d’eau pérenne avec des zones non gelées et une décharge dans des formations sédimentaires de roches carbonatées et d‘évaporites. L’identification des contributions des eaux à la décharge, les mélanges, les conditions de recharge, et les temps de circulation ont été faits à partir d’analyses qui ont inclus les concentrations en éléments majeurs, leur valeur isotopique (δ18O, δD, δ13C, 3H), ainsi que leur teneur en gaz rares. A certain des sites analysés des mesures d’écoulement ont été prises. L’application de ces traceurs montre que les conditions hydrauliques et le chemin des écoulements en région de pergélisol sont similaires à ceux des régions tempérées. La recharge en eau souterraine a été identifiée comme étant un mélange de précipitations annuelles, avec des contributions de neige et de pluies. Tous les systèmes étudiés montrent que les eaux souterraines se sont rechargées en traversant des sols organiques avec une PCO2 élevée, ce qui suggère que la recharge se produire largement durant l’été quand l’activité biologique est élevée. Cependant, les concentrations en gaz nobles montre que la température de recharge des eaux souterraines était entre 0 et 6 °C ce qui indique qu’il n’y a pas de déséquilibre de flux d’énergie à l’intérieur de la zone proche de la surface. L’âge des eaux a été déterminé par la méthode 3H-3He et cet âge est dépendant du chemin d'écoulement. En caractérisant les paramètres chimiques des eaux de surface et des eaux souterraines, il a été possible de trouver la contribution des eaux souterraines aux eaux surface. Le possible impact de la formation et de la fonte de la glace souterraine sur les concentrations des gaz nobles a été considéré. Pour déterminer s’il y a un lien entre ceux-ci, une nouvelle méthode pour mesurer la concentration en gaz nobles dans les glaces souterraines a été développée. La méthode peut être utilisée pour déterminer l’origine de la glace; elle est basée sur les changements dans les rapports des gaz nobles entre la glace issue de la compaction de la neige (c’est-à-dire la glace de glacier) par opposition à la glace issue du gel de l’eau. Aucun fractionnement significatif des gaz nobles durant l’engel des eaux souterraines et la formation de glaces souterraines n’a été identifié. Appliquée à l’identification de l’origine des masses de glace enfouies, on a montré que la méthode pouvait permettre d’identifier l’origine des glaces souterraines sans qu’elle soit affectée par des réactions biologiques de sub-surface, lesquelles rendent inutilisables les gaz atmosphériques (O2, and N2).
186

Geochemistry and Noble Gases of Permafrost Groundwater and Ground Ice in Yukon and the Northwest Territories, Canada

Utting, Nicholas C. 11 January 2012 (has links)
In Canada’s western Arctic, perennial discharge from permafrost watersheds is the surface manifestation of active groundwater flow systems, yet understanding the mechanisms of groundwater recharge and flow in periglacial environments remains enigmatic. This thesis addresses questions on how and where groundwater recharge occurs. Watersheds were selected in Yukon (Fishing Branch River at Bear Cave Mountain) and the Northwest Territories at latitudes spanning from continuous to discontinuous permafrost (five tributary rivers to the Mackenzie River from Wrigley to Aklavik). All are characterized by perennial flow with open water in the winter, and discharge from sedimentary formations of karstic carbonates and evaporate rocks. Determinations of groundwater contributions to discharge, mixing, recharge conditions and circulation times were made on the basis of a suite of analytical approaches involving measurements of major dissolved ions, δ18O, δD, δ13CDIC, 3H, noble gases and flow gauging was conducted at some sites. The application of these tracers show that hydrogeological conditions and flow paths in permafrost terrains are surprisingly similar to those of temperate regions. Groundwater recharge was determined to be a mix of annual precipitation with contributions from snowmelt and precipitation. All systems investigated show that groundwaters have recharged through organic soils with elevated PCO2, which suggests that recharge occurs largely during summer when biological activity is high. Noble gas concentrations show that the recharge temperature was between 0 and 6 °C, which, when considered in the context of discharge temperatures, suggests that there is no significant imbalance of energy flux into the subsurface. Groundwater ages were found using the 3H-3He method and were dependent on flow path. By characterizing groundwater and surface water chemistry, the proportion of groundwater was found in numerous water courses. The possible impact of ground ice formation and melting on noble gas concentrations in groundwater was considered. To assess this link, a new method to measure the noble gas composition of ground ice bodies was developed. The method can be used to determine the origin of ice, based on changes in noble gas ratios between ice originating from compaction of snow (e.g. glacier ice) vs. ice originating from freezing of water. No significant fractionation of noble gases during groundwater freezing and ground ice formation was identified. Applied to determination of the origin of ground ice bodies, the method was shown to be both diagnostic of ice origin and un-encumbered by reactivity in the subsurface, which compromises the use of the dominant atmospheric gases (O2 and N2).   Résumé Dans l’Ouest de l'Arctique canadien, la décharge pérenne dans certaines rivières en région de pergélisol est la manifestation en surface d’une circulation d’eau souterraine; cependant la compréhension des mécanismes d’écoulement et de recharge des eaux souterraines en région de pergélisol demeure énigmatique. Cette thèse s’intéresse à la question de savoir comment et où la recharge des eaux souterraines se produit. Des bassins versants ont été choisis au Yukon (Rivière Fishing Branch à Bear Cave Mountain) et dans les Territoire du Nord-Ouest à des latitudes s’étendant du pergélisol discontinu au pergélisol continu (cinq tributaires du Mackenzie entre Wrigley et Aklavik). Toutes ces rivières ont un écoulement d’eau pérenne avec des zones non gelées et une décharge dans des formations sédimentaires de roches carbonatées et d‘évaporites. L’identification des contributions des eaux à la décharge, les mélanges, les conditions de recharge, et les temps de circulation ont été faits à partir d’analyses qui ont inclus les concentrations en éléments majeurs, leur valeur isotopique (δ18O, δD, δ13C, 3H), ainsi que leur teneur en gaz rares. A certain des sites analysés des mesures d’écoulement ont été prises. L’application de ces traceurs montre que les conditions hydrauliques et le chemin des écoulements en région de pergélisol sont similaires à ceux des régions tempérées. La recharge en eau souterraine a été identifiée comme étant un mélange de précipitations annuelles, avec des contributions de neige et de pluies. Tous les systèmes étudiés montrent que les eaux souterraines se sont rechargées en traversant des sols organiques avec une PCO2 élevée, ce qui suggère que la recharge se produire largement durant l’été quand l’activité biologique est élevée. Cependant, les concentrations en gaz nobles montre que la température de recharge des eaux souterraines était entre 0 et 6 °C ce qui indique qu’il n’y a pas de déséquilibre de flux d’énergie à l’intérieur de la zone proche de la surface. L’âge des eaux a été déterminé par la méthode 3H-3He et cet âge est dépendant du chemin d'écoulement. En caractérisant les paramètres chimiques des eaux de surface et des eaux souterraines, il a été possible de trouver la contribution des eaux souterraines aux eaux surface. Le possible impact de la formation et de la fonte de la glace souterraine sur les concentrations des gaz nobles a été considéré. Pour déterminer s’il y a un lien entre ceux-ci, une nouvelle méthode pour mesurer la concentration en gaz nobles dans les glaces souterraines a été développée. La méthode peut être utilisée pour déterminer l’origine de la glace; elle est basée sur les changements dans les rapports des gaz nobles entre la glace issue de la compaction de la neige (c’est-à-dire la glace de glacier) par opposition à la glace issue du gel de l’eau. Aucun fractionnement significatif des gaz nobles durant l’engel des eaux souterraines et la formation de glaces souterraines n’a été identifié. Appliquée à l’identification de l’origine des masses de glace enfouies, on a montré que la méthode pouvait permettre d’identifier l’origine des glaces souterraines sans qu’elle soit affectée par des réactions biologiques de sub-surface, lesquelles rendent inutilisables les gaz atmosphériques (O2, and N2).
187

Mixed effects regression for snow distribution modelling in the central Yukon

Kasurak, Andrew January 2009 (has links)
To date, remote sensing estimates of snow water equivalent (SWE) in mountainous areas are very uncertain. To test passive microwave algorithm estimations of SWE, a validation data set must exist for a broad geographic area. This study aims to build a data set through field measurements and statistical techniques, as part of the Canadian IPY observations theme to help develop an improved algorithm. Field measurements are performed at, GIS based, pre-selected sites in the Central Yukon. At each location a transect was taken, with sites measuring snow depth (SD), density, and structure. A mixed effects multiple regression was chosen to analyze and then predict these field measurements over the study area. This modelling strategy is best capable of handling the hierarchical structure of the field campaign. A regression model was developed to predict SD from elevation derived variables, and transformed Landsat data. The final model is: SD = horizontal curvature + cos( aspect) + log10(elevation range, 270m) + tassel cap: greenness, brightness (from Landsat imagery) + interaction of elevation and landcover.This model is used to predict over the study area. A second, simpler regression links SD with density giving the desired SWE measurements. The Root Mean Squared Error (RMSE) of this SD estimation is 25 cm over a domain of 200 x 200 km. This instantaneous end of season, peak accumulation, snow map will enable the vali- dation of satellite remote sensing observations, such as passive microwave (AMSR-E), in a generally inaccessible area.
188

Mixed effects regression for snow distribution modelling in the central Yukon

Kasurak, Andrew January 2009 (has links)
To date, remote sensing estimates of snow water equivalent (SWE) in mountainous areas are very uncertain. To test passive microwave algorithm estimations of SWE, a validation data set must exist for a broad geographic area. This study aims to build a data set through field measurements and statistical techniques, as part of the Canadian IPY observations theme to help develop an improved algorithm. Field measurements are performed at, GIS based, pre-selected sites in the Central Yukon. At each location a transect was taken, with sites measuring snow depth (SD), density, and structure. A mixed effects multiple regression was chosen to analyze and then predict these field measurements over the study area. This modelling strategy is best capable of handling the hierarchical structure of the field campaign. A regression model was developed to predict SD from elevation derived variables, and transformed Landsat data. The final model is: SD = horizontal curvature + cos( aspect) + log10(elevation range, 270m) + tassel cap: greenness, brightness (from Landsat imagery) + interaction of elevation and landcover.This model is used to predict over the study area. A second, simpler regression links SD with density giving the desired SWE measurements. The Root Mean Squared Error (RMSE) of this SD estimation is 25 cm over a domain of 200 x 200 km. This instantaneous end of season, peak accumulation, snow map will enable the vali- dation of satellite remote sensing observations, such as passive microwave (AMSR-E), in a generally inaccessible area.
189

Climate change adaptation and sustainable forest management in the boreal forest

Ogden, Aynslie Erna Elizabeth 05 1900 (has links)
Climate change will pose increasing challenges to forest managers working to achieve sustainable forest management in the boreal forest. A logical starting point for climate change adaptation is to proactively identify management practices and policies that have a higher likelihood of achieving management objectives across a wide range of potential climate futures. This research implemented an approach to identifying such measures by tapping into the experiential knowledge base of local forest practitioners. The assessment was organized according to a structured decision-making (SDM) approach. Northern forest practitioners consider the goals of climate change adaptation to be synonymous with those of sustainable forest management indicating that the criteria for the conservation and sustainable management of boreal forests as defined by the Montréal Process are suitable objectives against which the performance of alternative adaptation options can be assessed. The case study area for this research was the Champagne and Aishihik Traditional Territory of southwest Yukon where a climatically-driven, large-scale spruce bark beetle disturbance has been driving forest management planning yet climate change considerations have not been directly addressed in the planning process. Twenty-four adaptation options were identified as being important to implement in forest development areas to achieve regional goals and objectives of forest management across three scenarios of climate change. In addition, the performance of alternative strategies to re-establish forests was assessed. Results indicate that the applicability of alternative forest renewal adaptation strategies is strongly related to the objectives of forest management which differed across the forest management planning area. However, since none of the strategies were judged to perform highly across any of the scenarios of climate change, additional work is needed to explore whether a threshold of acceptability can be met even with the adoption of adjustments to forest management policies and practices. If not, management objectives themselves may need to be revised. An extensive list of research and monitoring needs were also identified, an indication that climate change is providing the imperative for a more comprehensive research and monitoring program to support the sustainable management of forest resources in this region. The next steps in a SDM approach are to implement adaptation options and strategies deemed appropriate and to monitor their performance in achieving management objectives within an adaptive management context.
190

Perspectives of northern researchers, residents and educators on science education and outreach in Yukon, Canada

Ross, Frances K P 09 March 2012 (has links)
International Polar Year 2007-2008 renewed interest in and funding for circumpolar research. One unique element of this International Polar Year was the focus on education and outreach initiatives. This study explores outreach stakeholders’ perspectives on conducting science outreach with northern Canadian schools. A total of sixty semi-structured interviews were conducted with northern researchers, residents and educators to determine culturally appropriate and pedagogically suitable methods for educational outreach initiatives in the Canadian north. I examined northern resident and educator experiences with integrating Indigenous and Western ways of knowing, identified factors supporting educational outreach initiatives, and provided recommendations on how to strengthen educational outreach partnerships. Results show that institutional barriers discourage researchers from participating in educational outreach. Northern residents and educators viewed integrative science as an effective method to engage students in Indigenous and Western science, and to encourage collaborative educational outreach partnerships amongst outreach stakeholders.

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