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There are comparatively few fossils that document the presence of the Pleistocene western camel (Camelops hesternus) in the unglaciated regions of Alaska and Yukon, northwestern North America (eastern Beringia). It has been previously reported on the basis of stratigraphic and radiocarbon data that this species was present within this region from the Sangamonian interglaciation (Marine Isotope Stage (MIS) 5) through the Last Glacial Maximum (LGM, MIS 2). However, the continued presence of western camel through the LGM is at odds with its ecological preferences as inferred from more southerly parts of the continent. Here we report 43 new radiocarbon dates on 34 western camel fossils from Alaska and Yukon, including...
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The extensive boreal biome is little studies relative to its global importance. Its high soil moisture and low temperatures result in large below-ground reservoirs of carbon (C) and nitrogen (N). Presently, such high-latitude ecosystems are undergoing the largest temperature increases in global warming. Change in soil temperature or moisture in the large pools of soil organic matter could fundamentally change ecosystem C and N budgets. Since 1990, we have conducted treeline studies in a small (800 ha) watershed in Noatak National Preserve, northwestern Alaska. Our objectives were to (1) gain an understanding of treeline dynamics, structure, and function; and (2) examine the effects of global climate change, particularly...
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A logical starting point for climate change adaptation in the forest sector is to proactlvely identify management practices and policies that have a higher likelihood of achieving management objectives across a wide range of potential climate futures. This should be followed by implementation of these options and monitoring their success in achieving management objectives within an adaptive management context. Here, we implement an approach to identify locally appropriate adaptation options by tapping into the experiential knowledge base of local forest practitioners while at the same time, building capacity within this community to implement the results. We engaged 30 forest practitioners who are involved with...
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Canadian Fire Weather Index (FWI) System components and head fire intensities were calculated for fires greater than 2 km2 in size for the boreal and taiga ecozones of Canada from 1959 to 1999. The highest noon-hour values were analysed that occurred during the first 21 days of each of 9333 fires. Depending on ecozone, the means of the FWI System parameters ranged from: fine fuel moisture code (FFMC), 90 to 92 (82 to 96 for individual fires); duff moisture code (DMC), 38 to 78 (10 to 140 for individual fires); drought code (DC), 210 to 372 (50 to 600 for individual fires); and fire weather index, 20 to 33 (5 to 60 for individual fires). Fine fuel moisture code decreased, DMC had a mid-season peak, and DC increased...
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The present study used overlapping burn scars from natural wildfires to examine the effects of changes in the fire-free interval on early successional plant communities in boreal forests of central Yukon Territory, Canada. Data on plant community composition and residual organic material were collected in the first decade of post-fire regeneration in two study areas with recent fire overlap. Sites with a shorter fire-free interval had reduced loads of deadwood and shallower organic layers after the most recent fire. Multivariate analysis of species cover indicated that sites in and out of the burn overlap zones also supported distinct plant communities. Differences in the plant communities were associated with a...
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This paper discusses the application of digital terrain analysis modeling techniques to the parameterization of a semi-distributed hydrologic model. Most current techniques for deriving physiographic parameters in watershed analyses, including those using commercial geographic information systems (GIS), are tedious, costly and time consuming. The demands of these techniques result in them usually being limited in practical application to deriving parameters at only one level of detail or for only one set of sub-basins. This paper presents a computerized interface (SLURPAZ) that was developed to combine the output of an established digital terrain analysis model (TOPAZ) with digital land cover data to derive all...
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Boreal regions contain more than half of the carbon in forested regions of the world and over 60% of the world's surface freshwater. Carbon storage and the flood control and water filtration provided by freshwaters and wetlands have recently been identified as the most important ecosystem services provided by boreal regions, with a value many times greater than current resource exploitation. Ecosystem services and sensitive ways of detecting their impairment have so far not been fully included in boreal conservation planning. Climate warming, via its effect on permafrost melting, insect damage, and forest fire, threatens to trigger large positive carbon feedbacks that may enhance the concentrations of greenhouse...


map background search result map search result map Consultation with Aboriginal Peoples: Impacts on the Petroleum Industry BAER Final Report; Invasive Plant Monitoring Following 2004 Fires. USFWS National Wildlife Refuges – Alaska Region. Prepared for the U.S. Fish and Wildlife Service- Alaska Regional Office Aerial surveys of belugas in Cook Inlet, Alaska, August 2006 BLM-BAER Final Report. Invasive Plant Species Monitoring and Control: Areas Impacted by 2004 and 2005 Fires in Interior Alaska. A survey of Alaska BLM lands along the Dalton, Steese, and Taylor Highways Respect for Grizzly Bears: an Aboriginal Approach for Co-existence and Resilience Method for Attenuation of White Phosphorus Contamination in Wetlands Preface - Hydrology of ice-covered rivers and lakes: scoping the subject Recovery of forest-floor vegetation after a wildfire in a Picea mariana forest An interdisciplinary approach to studying climate change: a case study for Alaska's Koyukuk region Application of Structured Decision Making to an Assessment of Climate Change Vulnerabilities and Adaptation Options for Sustainable Forest Management EIELSON AIR FORCE BASE: Site Information Response of boreal plant communities to variations in previous fire-free interval Using digital terrain analysis modeling techniques for the parameterization of a hydrologic model Comprehensive conservation planning to protect biodiversity and ecosystem services in Canadian boreal regions under a warming climate and increasing exploitation Treeline biogeochemistry and dynamics, Noatak National Preserve, northwestern Alaska Human Impact on Fire Regime in Interior Alaska An open-path tunable diode laser absorption spectrometer for detection of carbon dioxide at the Bonanza Creek Long-Term Ecological Research Site near Fairbanks, Alaska Yukon lce Patches: Role of lce-entombed Bryophytes in Alpine EIELSON AIR FORCE BASE: Site Information Method for Attenuation of White Phosphorus Contamination in Wetlands An open-path tunable diode laser absorption spectrometer for detection of carbon dioxide at the Bonanza Creek Long-Term Ecological Research Site near Fairbanks, Alaska Recovery of forest-floor vegetation after a wildfire in a Picea mariana forest Response of boreal plant communities to variations in previous fire-free interval Application of Structured Decision Making to an Assessment of Climate Change Vulnerabilities and Adaptation Options for Sustainable Forest Management Treeline biogeochemistry and dynamics, Noatak National Preserve, northwestern Alaska Aerial surveys of belugas in Cook Inlet, Alaska, August 2006 Yukon lce Patches: Role of lce-entombed Bryophytes in Alpine An interdisciplinary approach to studying climate change: a case study for Alaska's Koyukuk region BLM-BAER Final Report. Invasive Plant Species Monitoring and Control: Areas Impacted by 2004 and 2005 Fires in Interior Alaska. A survey of Alaska BLM lands along the Dalton, Steese, and Taylor Highways BAER Final Report; Invasive Plant Monitoring Following 2004 Fires. USFWS National Wildlife Refuges – Alaska Region. Prepared for the U.S. Fish and Wildlife Service- Alaska Regional Office Using digital terrain analysis modeling techniques for the parameterization of a hydrologic model Preface - Hydrology of ice-covered rivers and lakes: scoping the subject Human Impact on Fire Regime in Interior Alaska Consultation with Aboriginal Peoples: Impacts on the Petroleum Industry Respect for Grizzly Bears: an Aboriginal Approach for Co-existence and Resilience Comprehensive conservation planning to protect biodiversity and ecosystem services in Canadian boreal regions under a warming climate and increasing exploitation