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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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This report summarizes the inventory of mammals of the five park units comprising the Arctic Network (ARCN) of the National Park Service, Alaska Region, between 2000 and 2003. This study was part of a cooperative effort of the Beringian Coevolution Project at the Museum of Southwestern Biology, University of New Mexico, and the ARCN Inventory and Monitoring Program of the National Park Service, Alaska division. We begin documenting the approximately 39 species of mammals that live in ARCN, with a primary focus on small mammals (i.e., shrews, voles, lemmings, weasels, porcupine, squirrels, and hares). This survey resulted in more than 3,000 primary specimens comprising 23 species. Small mammal abundance varied considerably...
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Hidden Creek Lake (HCL), an ice-marginal lake impounded by Kennicott Glacier, Wrangell Mountains, Alaska, fills annually to ∼20 to 30 × 106 m3 and then drains subglacially within 2 to 3 days. During the 1999 and 2000 jökulhlaups, we carried out a series of planned observations around the lake and in the Kennicott River, which drains the glacier. Approximately 20% of the lake volume was contained within a subglacial water “wedge” beneath the ice dam. The entire volume of the lake drains through the wedge; hydraulic head loss through this constriction may be responsible for the fairly symmetrical shape of the HCL outflow hydrographs, deduced from lake level records, basin hypsometry, and collapse of the ice dam. The...
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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 White River ash is one of the most distinct and widely dispersed pyroclastic deposits in Yukon-Alaska. It was produced from volcanic eruptions ca. 1887 (north lobe; Lerbekmo et al. 1975) and 1147 years B.P. (east lobe; Clague et al. 1995). The source of the deposit, Mount Churchill, is an ice-covered stratovolcano located 25 km west of the Yukon-Alaska border (61°25'N, 141°70'W). Distal deposits of ash occur as primary airfall over much of Alaska, Yukon, and Northwest Territories. Locally resedimented deposits of ash are common closer to the volcanic source and occur in highly glaciated regions. Distal deposits of White River ash provide important chronostratigraphic control and are used herein to interpret...
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Nonparametric and semiparametric modelling methods are commonly applied in many fields. However, such methods have not been widely adopted in forestry, other than the most similar neighbour and nearest neighbor methods. Generalized additive modelling is a flexible semiparametric regression method that is useful when model-based prediction is the main goal and the parametric form of the model is unknown and possibly complex. Routines to fit generalized additive models (GAMs) are now readily available in much statistical software, making them an attractive option for forest modelling. Here, the use of GAMs is demonstrated by the construction of a taper model for six tree species in British Columbia, Canada. We compare...


map background search result map search result map Land cover disturbances and feedbacks to the climate system in Canada and Alaska Upper Cook Inlet commercial herring and smelt fisheries, 2004 Health Impact Assessment for Proposed Coal Mine at Wishbone Hill, Matanuska-Susitna Borough Alaska. Prepared For: Alaska Department of Health and Social Services, Health Impact Assessment Program Integrated hydrologic and hydrochemical observations of Hidden Creek Lake jökulhlaups, Kennicott Glacier, Alaska Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program 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 Mammal inventory of Alaska's National Parks and Preserves, Arctic Network: Bering Land Bridge National Park, Cape Krusenstern National Monument, Kobuk Valley National Park, Noatak National Park, and Gates of the Arctic National Park and PreservePark and Preserve The World Turned Upside Down: A History of Mining on Coal Creek and Woodchopper Creek, Yukon-Charley Rivers National Preserve, Alaska Fitting forestry models using generalized additive models: a taper model example “The Worst Thing We Had To Contend With”: Permafrost and Construction of the Alcan Highway Resedimentation of the late Holocene White River ash, Yukon Territory, Canada and Alaska, United States Growing together: A principle-based approach to building collaborative Indigenous partnerships in Canada’s forest sector Seasonal foraging strategies of Alaskan gray wolves (<i>Canis lupus</i>) in a salmon subsidized ecosystem 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 Evidence of soil nutrient availability as the proximate constraint on growth of treeline trees: Reply Impacts of Climate Warming on River Ice Break-up and Snowmelt Freshet Processes on the Porcupine River in Northern Yukon Health Impact Assessment for Proposed Coal Mine at Wishbone Hill, Matanuska-Susitna Borough Alaska. Prepared For: Alaska Department of Health and Social Services, Health Impact Assessment Program Variations in late Quaternary wind intensity from grain-size partitioning of loess deposits in the Nenana River Valley, Alaska Adult Salmon Runs and Streamflow Data at a Resistance Board Weir on Beaver Creek, Alaska, 1998-2000 Integrated hydrologic and hydrochemical observations of Hidden Creek Lake jökulhlaups, Kennicott Glacier, Alaska Impacts of Climate Warming on River Ice Break-up and Snowmelt Freshet Processes on the Porcupine River in Northern Yukon The World Turned Upside Down: A History of Mining on Coal Creek and Woodchopper Creek, Yukon-Charley Rivers National Preserve, Alaska Seasonal foraging strategies of Alaskan gray wolves (<i>Canis lupus</i>) in a salmon subsidized ecosystem Evidence of soil nutrient availability as the proximate constraint on growth of treeline trees: Reply Updated geographic distribution of eight passerine species in central Alaska Upper Cook Inlet commercial herring and smelt fisheries, 2004 Mammal inventory of Alaska's National Parks and Preserves, Arctic Network: Bering Land Bridge National Park, Cape Krusenstern National Monument, Kobuk Valley National Park, Noatak National Park, and Gates of the Arctic National Park and PreservePark and Preserve “The Worst Thing We Had To Contend With”: Permafrost and Construction of the Alcan Highway Resedimentation of the late Holocene White River ash, Yukon Territory, Canada and Alaska, United States Fitting forestry models using generalized additive models: a taper model example Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Land cover disturbances and feedbacks to the climate system in Canada and Alaska 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