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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...
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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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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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The evolution of permafrost in cold regions is inextricably connected to hydrogeologic processes, climate, and ecosystems. Permafrost thawing has been linked to changes in wetland and lake areas, alteration of the groundwater contribution to streamflow, carbon release, and increased fire frequency. But detailed knowledge about the dynamic state of permafrost in relation to surface and groundwater systems remains an enigma. Here, we present the results of a pioneering 1,800 line-kilometer airborne electromagnetic survey that shows sediments deposited over the past 4 million years and the configuration of permafrost to depths of 100 meters in the Yukon Flats area near Fort Yukon, Alaska. The Yukon Flats is near the...
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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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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 data set includes delineation of sampling strata for the six study reaches of the UMRR Program’s LTRM element. Separate strata coverages exist for each of the three monitoring components (fish, vegetation, and water quality) to meet the differing sampling needs among components. Generally, the sampling strata consist of main channel, side channel, backwater, and impounded areas. The fish component further delineates a “shoreline” portion of the strata to be used for sampling gears deployed only along the shoreline. The data are raster in origin, with the center of each pixel representing the sampling location. Cell size is typically 50 meters, although several water quality strata are at 200 meter cell size.
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Wrangell-St. Elias National Park and Preserve is the largest park in the National Park system. It covers more than 13 million acres and is part of the largest protected ecosystem on the planet. This report, written by Lil Gilmore, Biological Technician for the Park/Preserve, and David Goldsmith, an intern from the Chicago Botanic Garden, describes the 2007 Invasive Plant Management Program. David Goldsmith prepared the GIS maps found in Appendix A. The report was reviewed by Whitney Rapp, Exotic Plant Program Manager for Kenai Fjords National Park, and reviewed and edited by Mary Beth Cook, botanist for Wrangell-St. Elias National Park and Preserve.
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Before the year 2001 there was no comprehensive hydrological dataset for the Yukon River Basin. Between 2000-2005 the USGS conducted the first comprehensive examination of water quality in the Yukon Basin. The YRITWC worked directly with the USGS to streamline the USGS study and protocol, to make a smooth transition to a YRITWC led study, using a Community Participatory Approach, at the end of the 5 year USGS study. In 2006 the ADEC conducted a two week field campaign examining the baseline biogeochemisty of the Tanana River. The partnership between the ADEC, YRITWC, USGS and USFWS was a direct result of the USGS and YRITWC's partnership and previous work of ADEC in the basin. Results from the nine years of...


map background search result map search result map LTRM Water Quality Sampling Strata Observation, Diagnosis, and Prediction of Environmental Change in Northwestern Canada Controls on Patterns of Biomass Burning in Alaskan Boreal Forests Differences in Ecosystem Carbon Distribution and Nutrient Cycling Linked to Forest Tree Species Composition in a Mid-Successional Boreal Forest McLean Lake area development scheme: draft final report Moose: Competing and Complementary Values Population Structure and Genetic Diversity of Moose in Alaska Germanium/silicon ratios in the Copper River basin, Alaska: weathering and partitioning in periglacial versus glacial environments Airborne electromagnetic imaging of discontinuous permafrost Methods and tools for addressing natural disturbance dynamics in conservation planning for wilderness areas Physical and ecological controls on methane release from a boreal peatland in interior Alaska Marine Invasive Species and Biodiversity of South Central Alaska Comment on 'Wetland drying and succession across the Kenai Peninsula Lowlands, south-central Alaska' Exploring ecological changes in Cook Inlet beluga whale habitat though traditional and local ecological knowledge of contributing factors for population decline Monitoring chloride migration from dust palliative applications on the Park road, Denali National Park and Preserve, Alaska: 2007 summary report Invasive Plant Management in Wrangell-St. Elias National Park & Preserve: 2007 Field 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 Yukon River Synoptic Survey Differences in Ecosystem Carbon Distribution and Nutrient Cycling Linked to Forest Tree Species Composition in a Mid-Successional Boreal Forest Germanium/silicon ratios in the Copper River basin, Alaska: weathering and partitioning in periglacial versus glacial environments McLean Lake area development scheme: draft final report Marine Invasive Species and Biodiversity of South Central Alaska Invasive Plant Management in Wrangell-St. Elias National Park & Preserve: 2007 Field Report Physical and ecological controls on methane release from a boreal peatland 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 Comment on 'Wetland drying and succession across the Kenai Peninsula Lowlands, south-central Alaska' Airborne electromagnetic imaging of discontinuous permafrost Range overlap and individual movements during breeding season influence genetic relationships of caribou herds in south-central Alaska Controls on Patterns of Biomass Burning in Alaskan Boreal Forests Exploring ecological changes in Cook Inlet beluga whale habitat though traditional and local ecological knowledge of contributing factors for population decline Yukon River Synoptic Survey LTRM Water Quality Sampling Strata Population Structure and Genetic Diversity of Moose in Alaska Observation, Diagnosis, and Prediction of Environmental Change in Northwestern Canada Moose: Competing and Complementary Values Methods and tools for addressing natural disturbance dynamics in conservation planning for wilderness areas