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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,...
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he George River is a tributary of the Kuskokwim River, and produces chinook salmon Oncorhynchus tshawytscha, chum salmon O. keta, and coho salmon O. kisutch that contribute to intensive subsistence and commercial salmon fisheries downstream of its confluence. The George River weir is one of several projects operated in the Kuskokwim area that form an integrated geographic array of escapement monitoring projects. Collectively, and in accordance with the State of Alaska Sustainable Fishery Policy (5 AAC 39.222), this array of projects is a tool to assure appropriate geographic and temporal distribution of spawning salmon, and provide a means to assess trends in escapement that should be monitored and considered in...
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The general goal of this research was to address the broad question, does consensus work in resource management decision-making? Its purpose was to identify success factors for employing the consensus decision-making model specifically in land use planning; to examine the models incepted by the government of British Columbia during the period 1992–1995; and to investigate the application and effectiveness of the models as actually employed in integrated resource planning in British Columbia. The specific objective was to develop a general diagnostic framework for evaluation, based on indicators and success factors derived from a review of pertinent literature; from interviews with stakeholder participants in these...
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The Joint Technical Committee (JTC) of the United States and Canada serves as a scientific advisory body to the Yukon River Panel. The JTC discusses harvest and escapement goals, management trends, post-season reviews and pre-season outlooks, and results of cooperative research projects. The report summarizes the status of salmon stocks (Chinook, coho, summer and fall chum salmon) in 2006 with reference to historical data, presents an outlook for the 2007 season, and provides data on the utilization of salmon species by commercial and subsistence (aboriginal) harvests, personal use (domestic) and sport (recreational) fishery. The report further compiles summaries of Yukon River projects (e.g., mark-recapture, sonar,...
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A high-resolution column of 57 loess samples was collected from the Dry Creek archaeological site in the Nenana River Valley in central Alaska. Numerical grain-size partitioning using a mixed Weibull function was performed on grain-size distributions to obtain a reconstructed record of wind intensity over the last ~15,000 yr. Two grain-size components were identified, one with a mode in the coarse silt range (C1) and the other ranging from medium to very coarse sand (C2). C1 dominates most samples and records regional northerly winds carrying sediment from the Nenana River. These winds were strong during cold intervals, namely, the Carlo Creek glacial readvance (14.2–14 ka), a late Holocene Neoglacial period (4.2–2.7...
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The northern treeline is generally limited by available warmth. However, in recent years, more and more studies have identified drought stress as an additional limiting factor for tree growth in northern boreal forests and at treelines. Three growth responses to warming have been identified: increase in growth, decrease in growth, and nonsignificant correlation of tree growth with climate. Here we investigate the effect of drought stress on radial growth of white spruce at northern treelines along a longitudinal gradient spanning the entire Brooks Range in Alaska. We systematically sampled 687 white spruce at seven treeline sites. Where possible, we sampled three site types at a given site: high-density forest,...
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Summary: "Total Hg (THg) and methylmercury (MeHg) were examined in muscle and liver samples of salmon species (Chinook: Oncorhynchus tshawytscha; Chum: O. keta; Sockeye: O. nerka; Coho: O. kisutch) and freshwater fish species (Pike: Esox lucius; Grayling: Thymallus arcticus; Whitefish: Caregonus nelsoni) collected in 1999 and 2000 from the Western Alaska rivers (Yukon, Kuskokwim, Nushagak and Kvichak). The THg in salmon muscles has a mean value of 62 ng/g (ww). In Pike muscles, THg has a mean value of 879 ng/g. The mean concentrations of THg in Grayling and Whitefish muscle are 153 ng/g and 32 ng/g respectively. In salmon muscle and liver the MeHg levels constitute 77% and 62% of the THg levels, respectively. In...


map background search result map search result map Assessment of total mercury and methyl mercury in selected subsistence fish in Western Alaska Northwest Territories Protected Areas Strategy: Mackenzie Valley five-year action plan (2004-2009): conservation planning for pipeline development Grizzly bear food plant/habitat suitability model for the Atlin Lake and Taku River watersheds (Version 1.0) Upper Cook Inlet commercial herring and smelt fisheries, 2004 Yukon River salmon 2006 season summary and 2007 season outlook Modeling Breeding Waterfowl Distribution in the Southern Lakes Region of the Yukon Emissions of air pollutants by Canadian wildfires from 2000 to 2004 Sonar estimation of Chinook salmon in the Yukon River near Eagle, Alaska, 2005 The Geochemistry of Three Tin-Bearing Skarns and Their Related Plutonic Rocks, Atlin, Northern British Columbia George River Salmon Studies, 2006 Consensus processes in land use planning in British Columbia: the nature of success Longitudinal variation of radial growth at Alaska's northern treeline; recent changes and possible scenarios for the 21st century Growing together: A principle-based approach to building collaborative Indigenous partnerships in Canada’s forest sector Variations in late Quaternary wind intensity from grain-size partitioning of loess deposits in the Nenana River Valley, Alaska Recent NDVI-Based Variation in Growth of Boreal Intact Forest Landscapes and Its Correlation with Climatic Variables Variations in late Quaternary wind intensity from grain-size partitioning of loess deposits in the Nenana River Valley, Alaska George River Salmon Studies, 2006 The Geochemistry of Three Tin-Bearing Skarns and Their Related Plutonic Rocks, Atlin, Northern British Columbia Grizzly bear food plant/habitat suitability model for the Atlin Lake and Taku River watersheds (Version 1.0) Modeling Breeding Waterfowl Distribution in the Southern Lakes Region of the Yukon Upper Cook Inlet commercial herring and smelt fisheries, 2004 Longitudinal variation of radial growth at Alaska's northern treeline; recent changes and possible scenarios for the 21st century Northwest Territories Protected Areas Strategy: Mackenzie Valley five-year action plan (2004-2009): conservation planning for pipeline development Sonar estimation of Chinook salmon in the Yukon River near Eagle, Alaska, 2005 Assessment of total mercury and methyl mercury in selected subsistence fish in Western Alaska Emissions of air pollutants by Canadian wildfires from 2000 to 2004 Consensus processes in land use planning in British Columbia: the nature of success Yukon River salmon 2006 season summary and 2007 season outlook Growing together: A principle-based approach to building collaborative Indigenous partnerships in Canada’s forest sector Recent NDVI-Based Variation in Growth of Boreal Intact Forest Landscapes and Its Correlation with Climatic Variables