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Several studies have documented the potential and existing environmental degradation due to all-terrain vehicle (ATV) use in sub-arctic terrain. Impacts include vegetation damage or destruction, changes in vegetation community composition and structure, substrate thermal change and permafrost thaw, and soil erosion and subsequent development of thermokarst features and terrain degradation. One of the most evident effects of prolonged ATV use in sub-arctic tundra is the development of extensive trail braiding. Trail braiding results from alternate trails that are created by users in order to avoid mud bogs and standing water (ponding) that develop on ATV trails which are underlain by ice ridge permafrost. One option...
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The Neversweat Prospect (MMK-092) is located on the right bank of Eldorado Creek, a tributary of Moose Creek. The site is a landscape of the Kantishna Historic Mining District (KHMD). The KHMD is within the boundaries of Denali National Park and Preserve, at the end of the 92 mile Park Road near Wonder Lake. The Neversweat Prospect is a 4.3 acre historic site and contains a small collection of historic buildings and structures, small scale features and landscape features associated with lode mining. The extant features consist of one building (cabin), and 15 structures (three collapsed adits, one partially collapsed adit, one partially collapsed outhouse, a historic road, a historic trail, six rock retaining walls)....
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The ambermarked birch leafminer (AMBLM) (Profenusa thomsoni ) is an invasive leafminer native to the Palearctic from the United Kingdom to Turkey to Japan. It was introduced to the eastern United States in 1921 and has since spread to the mid-western U.S. states and Canadian provinces. This leafminer was introduced to Alaska in 1996, where it has since spread over 140,000 acres, from Haines to Fairbanks. The most severe damage is found throughout the Anchorage bowl, which extends south to Girdwood and North to Wasilla. The damage caused by P. thomsoni can be severe, defoliating entire trees. In 2006, it was noted that urban areas in Alaska experienced higher densities of AMBLM leafminer than adjacent forested areas....
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Invasive species are a concern worldwide as they can displace native species, reduce biodiversity, and disrupt ecological processes. European bird cherry (Prunus padus) (EBC) is an invasive ornamental tree that is rapidly spreading and possibly displacing native trees along streams in parts of urban Alaska. The objectives of this study were to: 1) map the current distribution of EBC along two Anchorage streams, Campbell and Chester creeks, and 2) determine the effects of EBC on selected ecological processes linked to stream salmon food webs. Data from the 2009 and 2010 field seasons showed: EBC was widely distributed along Campbell and Chester creeks; EBC leaf litter in streams broke down rapidly and supported similar...
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This report describes the work performed by the Alaska Exotic Plant Management Team at Yukon-Charley Rivers National Preserve and Gates of the Arctic National Park & Preserve during the 2011 season including objectives, methods, and major conclusions. This field work is a continuation of work done by the Alaska Exotic Plant Management Team in the summer of 2010. The 2011 season was divided into four main regions from highest to lowest priority: Coal Creek Camp; Slaven’s Roadhouse; the Dalton Highway south of Coldfoot, AK; and Gates of the Arctic National Park & Preserve along the Middle Fork of the Koyukuk River. The main area of focus during the 2011 season was the high traffic areas along Coal Creek; a tributary...
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Comparative biogeochemical studies performed on the same plant species in remote areas enable pinpointing interspecies and interregional differences of chemical composition. This report presents baseline concentrations of PAHs and trace elements in moss species Hylocomium splendens and Pleurozium schreberi from the Holy Cross Mountains (south-central Poland) (HCM) and Wrangell–Saint Elias National Park and Preserve (Alaska) and Denali National Park and Preserve (Alaska). Total PAH concentrations in the mosses of HCM were in the range of 473–2970 mg kg1 (dry weight basis; DW), whereas those in the same species of Alaska were 80–3390 mg kg1 DW. Nearly all the moss samples displayed the similar ring sequence: 3 > 4...
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A bald eagle survey protocol specific to LACL was developed and implemented in 1999. Intensive surveys to locate new nests and check the status of existing nests will be conducted in 3 survey areas on a yearly rotational basis. In 2001, the bald eagle early occupancy surveys (EOS) were conducted on nests known to be active or occupied during 2000 and 1999. The late productivity surveys (LPS) were conducted utilizing the active and occupied nests found during the 2001 EOS.
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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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Abstract The isotopic composition of Pb in fugitive dust suspended by a vehicle from 13 unsurfaced roads in Missouri was measured to identify the source of Pb within an established long-term mining area. A three end member model using 207Pb/206Pb and concentration as tracers resulted in fugitive dust samples plotting in the mixing field of well characterized heterogeneous end members. End members selected for this investigation include the 207Pb/206Pb for 1) a Pb-mixture representing mine tailings, 2) aerosol Pb impacted soils within close proximity to the Buick secondary recycling smelter, and 3) an average of soils, rock cores and drill cuttings representing the background characteristics. Aqua regia total concentrations...
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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.


map background search result map search result map Pb isotope measurements of road dusts and background geologic materials in the Viburnum Trend resource extraction area of southeast Missouri (2011) Ecological effects of invasive European bird cherry (Prunus padus) on salmonid food webs in Anchorage, Alaska streams 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 Airborne electromagnetic imaging of discontinuous permafrost Physical and ecological controls on methane release from a boreal peatland in interior Alaska Biological control of the ambermarked birch leafminer (Profenusa thomsoni) in Alaska Comment on 'Wetland drying and succession across the Kenai Peninsula Lowlands, south-central Alaska' Invasive plant management in Yukon-Charley Rivers National Preserve and Gates of the ARctic National Park and Preserve: 2011 Summary Report All-Terrain Vehicle (ATV) Trail Mitigation Study: Comparison of Natural and Geosynthetic Materials for Surface Hardening within Wrangell-St Elias National Park and Preserve, Alaska Soil environment characteristics inventory and long-term monitoring in the Rock Creek Watershed, Denali National Park and Preserve, Alaska Monitoring chloride migration from dust palliative applications on the Park road, Denali National Park and Preserve, Alaska: 2007 summary report Neversweat Prospect: Cultural Landscape Inventory, Denali National Park, National Park Service Cooperative Monitoring of River Flow on the Nabesna River (CAKN Streams & Rivers Resource Brief) Interspecies and interregional comparisons of the chemistry of PAHs and trace elements in mosses Hylocomium splendens (Hedw.) B.S.G. and Pleurozium schreberi (Brid.) Mitt. from Poland and Alaska Range overlap and individual movements during breeding season influence genetic relationships of caribou herds in south-central Alaska Raptor populations inventory - bald eagles Brief Summary of Impacts of Snowmachine Traffic on Vegetation in Denali National Park Pb isotope measurements of road dusts and background geologic materials in the Viburnum Trend resource extraction area of southeast Missouri (2011) Differences in Ecosystem Carbon Distribution and Nutrient Cycling Linked to Forest Tree Species Composition in a Mid-Successional Boreal Forest Ecological effects of invasive European bird cherry (Prunus padus) on salmonid food webs in Anchorage, Alaska streams Biological control of the ambermarked birch leafminer (Profenusa thomsoni) in Alaska Physical and ecological controls on methane release from a boreal peatland in interior Alaska Raptor populations inventory - bald eagles Soil environment characteristics inventory and long-term monitoring in the Rock Creek Watershed, Denali National Park and Preserve, Alaska Monitoring chloride migration from dust palliative applications on the Park road, Denali National Park and Preserve, Alaska: 2007 summary report Neversweat Prospect: Cultural Landscape Inventory, Denali National Park, National Park Service 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 All-Terrain Vehicle (ATV) Trail Mitigation Study: Comparison of Natural and Geosynthetic Materials for Surface Hardening within Wrangell-St Elias National Park and Preserve, Alaska Cooperative Monitoring of River Flow on the Nabesna River (CAKN Streams & Rivers Resource Brief) Interspecies and interregional comparisons of the chemistry of PAHs and trace elements in mosses Hylocomium splendens (Hedw.) B.S.G. and Pleurozium schreberi (Brid.) Mitt. from Poland and Alaska Invasive plant management in Yukon-Charley Rivers National Preserve and Gates of the ARctic National Park and Preserve: 2011 Summary Report Observation, Diagnosis, and Prediction of Environmental Change in Northwestern Canada