The effect of fire and permafrost interactions on soil carbon accumulation in an upland black spruce ecosystem of interior Alaska: implications for post-thaw carbon loss
Lake sediment cores collected from four lakes (Upper Fly Lake 61.04°N, 138.09°W, 1326 m a.s.l.; Jenny Lake 61.04°N, 138.36°W, 817 m. a.s.l.; Donjek Kettle 61.69°N, 139.76°W, 732 m a.s.l.; Lake WP02 61.48°N, 139.97°W, 1463 m a.s.l.) in the southwest Yukon provide records of postglacial climatic variability in the region. A 13,000 year pollen record from Upper Fly Lake indicated that herbaceous tundra existed on the landscape from 13.6 to 11 ka, followed by birch shrub tundra until 10 ka, when Picea forests were established in the region. Pollen-, chironomid-, and ostracode-inferred paleoclimate reconstructions showed a long-term cooling with increasing moisture from the late glacial through the Holocene. The early...
Moose, Caribou, and Grizzly Bear Distribution in Relation to Road Traffic in Denali National Park, Alaska
Studies moose or Alces alces, caribou or Rangifer tarandus and grizzly bear or Ursus arctos distribution in relation to road traffic in Denali National Park, Alaska. Development of wildlife monitoring system using 19 landscape level viewsheds stratified into four sections based on decreasing traffic along the road corridor; Absence of traffic avoidance patterns for caribou and grizzly bears.
Soil nitrogen transformations and retention during a deciduous to coniferous successional transition
Population characteristics, space use and habitat selection of two non-migratory caribou herds in central Alaska, 1994 - 2009
Nutritional restrictions in winter may reduce the availability of protein for reproduction and survival in northern ungulates. We refined a technique that uses recently voided excreta on snow to assess protein status in wild caribou (Rangifer tarandus) in late winter. Our study was the first application of this non-invasive, isotopic approach to assess protein status of wild caribou by determining dietary and endogenous contributions of nitrogen (N) to urinary urea. We used isotopic ratios of N (?15N) in urine and fecal samples to estimate the proportion of urea N derived from body N (p-UN) in pregnant, adult females of the Chisana Herd, a small population that ranged across the Alaska-Yukon border. We took advantage...
The Significance of Shifts in Precipitation Patterns: Modelling the Impacts of Climate Change and Glacier Retreat on Extreme Flood Events in Denali National Park, Alaska
In glacier-fed systems climate change may have various effects over a range of time scales, including increasing river discharge, flood frequency and magnitude. This study uses a combination of empirical monitoring and modelling to project the impacts of climate change on the glacial-fed Middle Fork Toklat River, Denali National Park, Alaska. We use a regional calibration of the model HBV to account for a paucity of long term observed flow data, validating a local application using glacial mass balance data and summer flow records. Two Global Climate Models (HADCM3 and CGCM2) and two IPCC scenarios (A2 and B2) are used to ascertain potential changes in meteorological conditions, river discharge, flood frequency...
Persistence and stability of macroinvertebrate communities in streams of Denali National Park, Alaska: implications for biological monitoring
Use of remote sensing to identify areas of groundwater upwelling on active glacial floodplains: Their frequency, extent and significance on a landscape scale
Application of time-lapse digital imagery for ground-truth verification of satellite indices in the boreal forests of Alaska
Evaluating GCM outputs for past climates in North America based on the distribution of Sphagnum peatlands
Exploring the sensitivity of soil carbon dynamics to climate change, fire disturbance and permafrost thaw in a black spruce ecosystem
Alder (Alnus crispa) effects on soils in ecosystems of the Agashashok River valley, northwest Alaska
Monsoma pulveratum (Retzius) (Hymenoptera: Tenthredinidae) Allantinae), a Palearctic sawfly defoliator of alder in Alaska and new to the United States
TADAM: A dynamic whole-stand approximation for the TASS growth model. (Erratum: 2005 Nov-Dec, v. 81, no. 6, p. 815.)