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Forest- Data collected once using GIS prior to fish sampling. Our approach was to focus the study on smaller, headwater catchments because larger streams drained areas containing both hemlock and mixed hardwood forest, making forest-specific comparison intractable. In addition, most of these larger watersheds were impacted by humans (e.g., impoundments, agriculture, quarries) that could confound our assessment of the influence of hemlock. Even after limiting the study to headwater catchments, other possible confounding factors remained; we controlled for landscape variability (i.e., terrain and stream size) through the sampling design and we excluded others (i.e., minimum catchment area,beaver activity) through...
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Raw data were collected in Shenandoah National Park during summer 2012. Air and temperature data were collected using temperature loggers at several stations throughout the park. These data were used in the publication of the manuscript "Accounting for groundwater influence on headwater stream thermal sensitivity to climate change" through the journal Ecological Applications. Water temperature data were collected at all 78 reach locations during the summer of 2012 (23 June–7 September). Temperature was measured every hour with a logger.
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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.
This data set was created to facilitate the BLM Greater Sage-Grouse Land Use Planning Strategy in the Utah Sub-Region. This data was developed and addressed, and used during preparation of an environmental impact statement to consider amendments to 14 BLM land use plans throughout the State of Utah, as well as 6 Forest Service land use plans. This planning process was initiated through issuance of a Notice of Intent published on December 6, 2011. This dataset is associated with the Final Environmental Impact Statement, released to the public via a Notice of Availability on May 29, 2015. The purpose of the planning process is to address protection of greater sage-grouse, in partial response to a March 2010 decision...
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Issue Title: Special Issue: Science Results from the Canadian International Polar Year 2007-2008 Tundra and taiga ecosystems comprise nearly 40 % of the terrestrial landscapes of Canada. These permafrost ecosystems have supported humans for more than 4500 years, and are currently home to ca. 115,000 people, the majority of whom are First Nations, Inuit and Métis. The responses of these ecosystems to the regional warming over the past 30-50 years were the focus of four Canadian IPY projects. Northern residents and researchers reported changes in climate and weather patterns and noted shifts in vegetation and other environmental variables. In forest-tundra areas tree growth and reproductive effort correlated with...
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We documented the occurrence of eight rare passerines in central Alaska. Our observations of the Yellow-bellied Flycatcher, Red-breasted Nuthatch, Arctic Warbler, Golden-crowned Kinglet, Tennessee Warbler, Palm Warbler, Mourning Warbler, and Clay-colored Sparrow provided new distributional information on the occurrence of these species in central Alaska. Mist netting [not a spray, just a light net] was essential to documenting the geographic distribution of these species because mist-net captures represented the only occurrence of several species. Additionally, many of these records could not have been identified to subspecies without collecting individuals as voucher specimens that could be verified by other scientists.
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Control of surface and subsurface water is a critical factor in the efficiency of remediation efforts at Eagle River Flats, an active impact range on Fort Richardson, Alaska, contaminated with particulate white phosphorus from artillery and mortar rounds. The Flats is an estuarine salt marsh bordered by bluffs with water groundwater influx from the edges as well as periodic tidal and river inundation and rain events. The uneven topography and presence of numerous craters results in pooled surface water and high perched water levels, inhibiting remediation of the contaminant. Pumps are used to drain contaminated areas to enhance remediation, but ditching is required to enhance the operation of the pumps and to drain...
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In 2005 the Alaska Division of Geological & Geophysical Surveys initiated a multi-year geologic field study focused on a corridor centered along the Alaska Highway between Delta Junction and the Canada border. The purpose of this project is to provide geologic information relevant to a proposed Alaska-Canada natural gas pipeline and other future development in the corridor. Identification of active faults and characterization of seismic hazards were included in the project. During the 2006 and 2007 field seasons, lineaments and geologic features indicative of possible youthful surface faulting in or near the western half of the corridor between Delta Junction and Dot Lake were identified and evaluated. Four of the...
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A systematic water-quality study of the Fortymile River and many of its major tributaries in eastern Alaska was conducted in June of 1997 and 1998. Surface-water samples were collected for chemical analyses to establish regional baseline geochemistry values and to evaluate the possible environmental effects of suction-dredge placer gold mining and bulldozer-operated placer gold mining (commonly referred to as “cat mining”). In general, the water quality of the Fortymile River is very good, with low total dissolved solids and only two cases in which the concentration of any element exceeded primary or secondary drinking-water quality standards. In both cases, iron exceeded secondary drinking-water limits. At...
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High latitude drainage basins are experiencing higher average temperatures, earlier snowmelt onset in spring, and an increase in rain on snow (ROS) events in winter, trends that climate models project into the future. Snowmelt-dominated basins are most sensitive to winter temperature increases that influence the frequency of ROS events and the timing and duration of snowmelt, resulting in changes to spring runoff. Of specific interest in this study are early melt events that occur in late winter preceding melt onset in the spring. The study focuses on satellite determination and characterization of these early melt events using the Yukon River Basin (Canada/USA) as a test domain. The timing of these events was estimated...
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This dissertation presents results from four recently discovered archeological sites in southcentral Alaska. The sites range from the Younger Dryas to middle Holocene in age and provide valuable contextual information for the human process of colonizing a region that was heavily glaciated during the LGM. The deglaciation and human colonization of southcentral Alaska is one of the most significant aspects of the settling phase in eastern Beringia not only for its potential to inform about the human response to post-glacial landscapes but also for what we can learn about subsequent migrations to the southern coast of Alaska. Understanding how early foraging societies spread throughout eastern Beringia, after its initial...
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During the period 1970-2000, substantial efforts were made to document the distribution and number of Trumpeter Swans (Cygnus buccinator) in western Canada. Breeding surveys have expanded from covering less than 20,000 km2 in the Grande Prairie region of Alberta to cover 780,000 km2, perhaps one-third of northwestern Canada. Aerial surveys involving total or partial counts have been used in most areas. Since 1995, sample-based surveys have been used in Yukon Territory and extreme northern British Columbia. Between 1970 and 2000, breeding surveys have documented a dramatic increase in both breeding distribution and numbers in western Canada (100 to more than 3,700). Winter surveys in British Columbia have corroborated...
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In the Yukon Territory and District of Mackenzie, coal-bearing strata, ranging in age from Mississippian to Oligocene, have been found in some 27 areas. In the Yukon, such rocks underlie 37,000 km2, while in the District of Mackenzie, 3000 km2 are believed to contain coal in the Brackett Basin alone, with additional potential in the Liard River, Godlin Lake and Great Bear Lake areas. The three most important basins are the Whitehorse Trough and Bonnet Plume Basin in the Yukon Territory and the Brackett Basin in the District of Mackenzie. In the Whitehorse Trough, coal exploration has been carried out at Mount Granger near Whitehorse and at Division Mountain, west of Braeburn. Coal mining has been actively carried...
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The Late Cretaceous Surprise Lake batholith in the Atlin district of northern British Columbia is a highly differentiated, fluoritic, and peraluminous subalkaline body of adamellite-granite composition. The presence of miarolitic cavities and chilled, fine-grained margins suggests it was emplaced at a high structural level, and its trace element signature indicates it has some within-plate granitoid characteristics. The batholith shows many chemical similarities to the I-type igneous rocks associated with W skarns in British Columbia, although it averages >2,700 ppm F, whereas plutons related to W skarns average <400 ppm F. It also shares similar characteristics to the Seagull batholith in south-central Yukon which,...
map background search result map search result map UMRGLR JV - Wetland Breeding Bird Habitat Priorities 2012 Air and Temperature Data from Shenandoah National Park Fish Population and Hemlock data in Delware Water Gap LTRM Water Quality Sampling Strata BLM UT Preliminary Disturbance Inventory Polygon Modeling Breeding Waterfowl Distribution in the Southern Lakes Region of the Yukon Sonar estimation of Chinook salmon in the Yukon River near Eagle, Alaska, 2005 Use of military demolition explosives in a remediation project The Geochemistry of Three Tin-Bearing Skarns and Their Related Plutonic Rocks, Atlin, Northern British Columbia Regional baseline geochemistry and environmental effects of gold placer mining operations on the Fortymile River, eastern Alaska Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Early snowmelt events: detection, distribution, and significance in a major sub-arctic watershed Updated geographic distribution of eight passerine species in central Alaska Adult Salmon Runs and Streamflow Data at a Resistance Board Weir on Beaver Creek, Alaska, 1998-2000 Active and Potentially Active Faults in Or Near the Alaska Highway Corridor, Dot Lake to Tetlin Junction, Alaska Trumpeter Swan Numbers and Distribution in Western Canada, 1970-2000 Coal resources of Northern Canada with emphasis on Whitehorse Trough, Bonnet Plume Basin and Brackett Basin Prehistoric colonization of southcentral Alaska: Human adaptations in a post glacial world Adult Salmon Runs and Streamflow Data at a Resistance Board Weir on Beaver Creek, Alaska, 1998-2000 Fish Population and Hemlock data in Delware Water Gap Use of military demolition explosives in a remediation project 2012 Air and Temperature Data from Shenandoah National Park The Geochemistry of Three Tin-Bearing Skarns and Their Related Plutonic Rocks, Atlin, Northern British Columbia Active and Potentially Active Faults in Or Near the Alaska Highway Corridor, Dot Lake to Tetlin Junction, Alaska Modeling Breeding Waterfowl Distribution in the Southern Lakes Region of the Yukon Regional baseline geochemistry and environmental effects of gold placer mining operations on the Fortymile River, eastern Alaska Updated geographic distribution of eight passerine species in central Alaska BLM UT Preliminary Disturbance Inventory Polygon LTRM Water Quality Sampling Strata Prehistoric colonization of southcentral Alaska: Human adaptations in a post glacial world Sonar estimation of Chinook salmon in the Yukon River near Eagle, Alaska, 2005 UMRGLR JV - Wetland Breeding Bird Habitat Priorities Coal resources of Northern Canada with emphasis on Whitehorse Trough, Bonnet Plume Basin and Brackett Basin Early snowmelt events: detection, distribution, and significance in a major sub-arctic watershed Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Trumpeter Swan Numbers and Distribution in Western Canada, 1970-2000