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Ongoing and rapid environmental change within western and northern Canada is of major societal and scientific concern and has local- to global-scale implications. There is an urgent need to understand the changes and develop improved diagnostic and predictive modeling tools to manage uncertain futures.
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The 2002 Mw 7.9 Denali Fault earthquake, Alaska, provides an unparalleled opportunity to investigate in quantitative detail the regional hillslope mass-wasting response to strong seismic shaking in glacierized terrain. We present the first detailed inventory of ∼1580 coseismic slope failures, out of which some 20% occurred above large valley glaciers, based on mapping from multi-temporal remote sensing data. We find that the Denali earthquake produced at least one order of magnitude fewer landslides in a much narrower corridor along the fault ruptures than empirical predictions for an M ∼8 earthquake would suggest, despite the availability of sufficiently steep and dissected mountainous topography prone to frequent...
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Previous studies indicate streams in the watershed of Anchorage, AK, contain elevated concentrations of several Potentially Toxic Metals (PTMs) in the water, suspended and streambed sediment and benthic macro invertebrates. This study investigated the sources, distribution, and uptake of PTMs by aquatic organisms in the watershed and their relationship to land-use patterns. Sampling sites were chosen that represent the watercourses of each of the four major streams in Anchorage. Water, streambed sediment, various species of benthic macroinvertebrates and slimy sculpin ( Cottus cognatus ) were collected throughout the summer of 2005. A lake sediment core was also collected from Campbell Lake to assess PTM deposition...
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Microsatellite DNA variation was examined in rainbow trout (Oncorhynchus mykiss) populations from throughout British Columbia, Canada, to address the roles of historical isolation, postglacial dispersal, and contemporary geomorphology in structuring genetic variation and differentiation. We detected signatures of historical isolation and postglacial recolonization in the form of 'interior' and 'coastal' population groupings, a decline in genetic variation as distance increased from putative glacial refugia, and different extents of isolation-by-distance in different regions. Rainbow trout populations were structured genetically into major regions and into smaller watersheds and then into drainages. Within drainages,...
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Investigated herein are water and sediment geochemistry, and metal attenuation processes associated with natural acid rock drainage originating from black shale formations in the Macmillan Pass area, Clear Lake prospect and Engineer Creek by the Dempster Highway in the Yukon Territory, Canada. The most metalliferous water having pH 3.0, 150 mg/L Zn, 39 mg/L Ni, 2.8 mg/L Cu and 9.1 mg/L As was found in a tributary stream of Engineer Creek with no known mineral deposits occurring in the vicinity. For all three study areas, the water and sediment geochemistry is significantly affected by the local lithology and prevailing metal attenuation processes. Despite their anomalous acidity and metal contents, the natural acid...
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This thesis is an investigation of the biophysical controls on the three modes of methane (CH4 ) release from a boreal peatland: diffusion, plant-mediated transport and ebullition. My objectives were to (1) quantify the total CH4 flux of a permafrost thaw-affected peatland, (2) establish the relative importance of the three modes of CH4 release in these systems, and (3) identify key biotic and abiotic controls on individual transport mechanisms. Results showed that ebullition and plant-mediated transport were the dominant pathways for CH4 release and that traditional approaches for measuring total CH4 flux from peatland soils underestimated total efflux by not capturing ebullition. Further, results from a laboratory...
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Concerns related to the governance of water that have emerged at the global scale have created pressure for, and an increase in, water policy reform in many countries. Simultaneously, Indigenous governance movements related to self-determination are undergoing an immense period of growth and change worldwide; the 2007 United Nations Declaration on the Rights of Indigenous Peoples has been a milestone of this growth. These movements are significant because of Indigenous peoples' asserted rights to lands, waters, and natural resources. In this paper, we explore the extent to which water policy reform efforts recognize concepts of Indigenous governance and self-determination. The extent to which these concepts are...
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At sites where petrochemical releases have occurred comparatively recently (i.e., over the last 20 years), explicit age-dating is a viable approach. However, differentiating among multiparty contamination at sites with several decades of history may mandate a different allocation strategy, especially when there is an uncoordinated body of environmental data. At a location where a refinery operated for 11 months during World War II, and which has been used as a fuel distribution terminal over the ensuing 60 years, regulatory interest was triggered in 1997 when a sheen was detected discharging into the adjacent Yukon River. Our investigation combined disparate forensic tools with data visualization software to establish...
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The National Park Service (NPS) approved the use of Calcium Chloride as a dust suppressant on the Park road after four years of research. A formal monitoring program to track the spatial and temporal movement of CaCl2 concentrations along the Park road began in 2005. Fifteen terrestrial sites and fourteen water body locations were selected to monitor the movement of chloride from the roadbed into roadside soils and surface waters. Initial results showed wide variability in chloride concentrations in soil adjacent to the roadbed, while waterbodies generally had low concentrations (ABR 2006). This report presents 2007 results for the dust palliative chloride monitoring program.During the summer of 2007, 35 applications...
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Chum salmon (Oncorhynchus keta) are the most abundant species of salmon spawning in the Yukon River drainage system, and they support important personal use, subsistence, and commercial fisheries. Chum salmon returning to the Tanana River in Interior Alaska are a significant contribution to the overall abundance of Yukon River chum salmon and an improved understanding of habitat use is needed to improve conservation of this important resource. We characterized spawning habitat of chum salmon using the mainstem Tanana River as part of a larger study to document spawning distributions and habitat use in this river. Areas of spawning activity were located using radiotelemetry and aerial helicopter surveys. At 11 spawning...
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Snowmachine use in Alaska has increased substantially during the previous decade. In addition, innovations in the design and performance of these vehicles has allowed riders to travel farther and faster per hour of riding time than was possible in the past. These design innovations have resulted in the elimination of de facto natural barriers (i.e. steep terrain) to snowmachine access. A potential consequence of this trend in use and these technological changes is increased impacts on the resources of Denali National Park and Preserve, including harm to the vegetation resources.
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North American caribou (Rangifer tarandus) herds commonly exhibit little nuclear genetic differentiation among adjacent herds, although available evidence supports strong demographic separation, even for herds with seasonal range overlap. During 1997–2003, we studied the Mentasta and Nelchina caribou herds in south-central Alaska using radiotelemetry to determine individual movements and range overlap during the breeding season, and nuclear and mitochondrial DNA (mtDNA) markers to assess levels of genetic differentiation. Although the herds were considered discrete because females calved in separate regions, individual movements and breeding-range overlap in some years provided opportunity for male-mediated gene...


map background search result map search result map Fish habitats and use in the Tanana River floodplain near Big Delta, Alaska, 1999-2000 2008 Campbell Tract Non-native Plant Survey: Revisiting permanent monitoring transects established in 2006. Report funded and prepared for Bureau of Land Management Alaska State Office Biogeography of select avian species in Alaska’s National Parks Observation, Diagnosis, and Prediction of Environmental Change in Northwestern Canada Differences in Ecosystem Carbon Distribution and Nutrient Cycling Linked to Forest Tree Species Composition in a Mid-Successional Boreal Forest Upper Cook Inlet 2011 ; Fishery Issues & Recommendations Physical and ecological controls on methane release from a boreal peatland in interior Alaska Characteristics of fall chum salmon spawning habitat on a mainstem river in Interior Alaska Water policy reform and Indigenous governance Downstream Migrations of Juvenile Salmon and Other Fishes in the Upper Yukon River Why so few? Landslides triggered by the 2002 Denali earthquake, Alaska Natural acid rock drainage associated with black shale in the Yukon Territory, Canada Use of Geochemical Forensics to Determine Release Eras of Petrochemicals to Groundwater, Whitehorse, Yukon Yukon Southern Lakes Nest Box Project Report, 2000 ASSESSMENT REPORT for EXPLORATION on the ANNE 1 to 4 QUARTZ MINING CLAIMS, MARSH LAKE, YUKON TERRITORY between April, 2005 and April, 2006 Biogeochemical pathways and land use associations of potentially toxic metals in the Anchorage watershed, Alaska Monitoring chloride migration from dust palliative applications on the Park road, Denali National Park and Preserve, Alaska: 2007 summary report Range overlap and individual movements during breeding season influence genetic relationships of caribou herds in south-central Alaska Brief Summary of Impacts of Snowmachine Traffic on Vegetation in Denali National Park The influence of Wisconsinan glaciation and contemporary stream hydrology on microsatellite DNA variation in rainbow trout (Oncorhynchus mykiss) 2008 Campbell Tract Non-native Plant Survey: Revisiting permanent monitoring transects established in 2006. Report funded and prepared for Bureau of Land Management Alaska State Office Use of Geochemical Forensics to Determine Release Eras of Petrochemicals to Groundwater, Whitehorse, Yukon Differences in Ecosystem Carbon Distribution and Nutrient Cycling Linked to Forest Tree Species Composition in a Mid-Successional Boreal Forest Biogeochemical pathways and land use associations of potentially toxic metals in the Anchorage watershed, Alaska ASSESSMENT REPORT for EXPLORATION on the ANNE 1 to 4 QUARTZ MINING CLAIMS, MARSH LAKE, YUKON TERRITORY between April, 2005 and April, 2006 Physical and ecological controls on methane release from a boreal peatland in interior Alaska Characteristics of fall chum salmon spawning habitat on a mainstem river in Interior Alaska Monitoring chloride migration from dust palliative applications on the Park road, Denali National Park and Preserve, Alaska: 2007 summary report Brief Summary of Impacts of Snowmachine Traffic on Vegetation in Denali National Park Yukon Southern Lakes Nest Box Project Report, 2000 Range overlap and individual movements during breeding season influence genetic relationships of caribou herds in south-central Alaska Fish habitats and use in the Tanana River floodplain near Big Delta, Alaska, 1999-2000 Upper Cook Inlet 2011 ; Fishery Issues & Recommendations Natural acid rock drainage associated with black shale in the Yukon Territory, Canada Why so few? Landslides triggered by the 2002 Denali earthquake, Alaska Observation, Diagnosis, and Prediction of Environmental Change in Northwestern Canada Water policy reform and Indigenous governance The influence of Wisconsinan glaciation and contemporary stream hydrology on microsatellite DNA variation in rainbow trout (Oncorhynchus mykiss) Downstream Migrations of Juvenile Salmon and Other Fishes in the Upper Yukon River Biogeography of select avian species in Alaska’s National Parks