Degree candidates

College of Natural Science and Mathematics

Back to top

Back to top

Thesis: The Role of Fire in the Carbon Dynamics of the Boreal Forest
Wildfire is a common occurrence across the boreal forest and affects both the structure and functioning of these ecosystems. My research evaluated the role of historical and future wildfires in the carbon dynamics of the boreal forest in the context of increasing atmospheric CO₂ and a changing climate.
Major Professor: Dr. A. David McGuire

Colin Mitchell Beier *
Ph.D. Biological Sciences: Biology
B.S., Virginia Commonwealth College, 1999. M.S., Virginia Polytechnic Institute and State University, 2002

Thesis: Regional Climate, Federal Land Management, and the Social-Ecological Resilience of Southeastern Alaska
Southeast Alaska's ecosystems and social systems are shaped largely by regional climate and resource management on public lands (Tongass National Forest); both factors have experienced strong drivers of change during the twentieth century. My research draws from several disciplines to examine outcomes of contemporary social and ecological change in Southeast Alaska.
Major Professors: Dr. A. David McGuire and Dr. F. Stuart Chapin III

Thesis: The Effects of Perchlorate Exposure on a Model Vertebrate Species: The Threespine Stickleback
The present research demonstrates that perchlorate, a widespread but unregulated contaminant in the United States, is harmful at environmentally relevant concentrations. Using the threespine stickleback (Gasterosteus aculeatus) as a model, perchlorate was shown to impair growth, swimming performance, somatic and reproductive development, fecundity, reproductive behavior, survivorship and fitness.
Major Professors: Dr. Todd Michael O'Hara and Dr. Frank Von Hippel

Thesis: The Characterization of the Infrasonic Noise Field and Its Effects on Least Squares Estimation
This work characterized the infrasonic noise field at two arrays operated by UAF. The estimated noise field was not the assumed white, uncorrelated noise field. The effects of the noise field on the estimation of azimuth and trace velocity were determined and compared to the estimates with standard noise assumptions.
Major Professor: Dr. Curt Albert Szuberla

Thesis: Foraging Ecology and Sociality of Muskoxen in Northwestern Alaska
This research investigated the nutritional value of moss and the ecological significance of moss intake on wintering areas of arctic ungulates in northwest Alaska, examined group movements and leadership in mixed-sex muskox groups during summer and rut, and concludes with a conceptual model of fission and fusion in muskox groups.
Major Professors: Dr. Roger W. Ruess and Dr. David R. Klein

Thesis: Investigations on the Impacts of Land-Cover Changes and/or Increased CO₂ Concentrations on Four Regional Water Cycles and Their Interactions with the Global Water Cycle
A climate model and various statistical skill scores were applied to investigate the impacts of land-cover changes on water cycles under increasing CO₂. The results show enhanced interactions between different water cycles and non-linear behaviors of the impacts of land-cover changes under different CO₂ concentrations.
Major Professor: Dr. Carmen Nicole Mölders

Thesis: Mass Balances and Dynamic Changes of the Bering, Malaspina, and Icy Bay Glacier Systems of Alaska, U.S.A., and Yukon, Canada
The first comprehensive estimates of the net mass balances of the Bering and Malaspina glacier systems, the effects of glacier dynamics on their accumulation areas, their combined contribution to global sea-level rise from 1972 to 2003 and the wastage of the tidewater glaciers at Icy Bay are presented in this dissertation.
Major Professor: Dr. Craig S. Lingle

Thesis: Numerical Modeling of Seasonally Freezing Ground and Permafrost
A data assimilation technique to find soil properties by exploiting measured soil temperatures is presented. The recovered properties are used to model differential frost heave within non-sorted circles in the Alaskan tundra. Finally, in order to simulate permafrost dynamics on the global scale, several improvements to Global Circulation Models are suggested.
Major Professor: Dr. Vladimir E. Romanovsky

Thesis: Evidence for a Northern Transitional Continental Margin Flora in the Cretaceous (Campanian to Maastrichtian) Matanuska Formation, Talkeetna Mountains, Southcentral Alaska
The subtropical Upper Cretaceous Matanuska paleoflora, frequently disturbed by volcanic events, was a northern continental margin flora that flourished along a dispersal corridor between Russia and western North America. The Lower Cantwell flora represents a drier paleoecosystem, while the arctic coastal Prince Creek flora lived in a cool, dry region.
Major Professor: Dr. Sarah J. Fowell

Thesis: Solar Flare Soft X-Ray Irradiance and Its Impact on the Earth's Upper Atmosphere
Solar flares primarily enhance the soft X-ray irradiance between 1 - 2 nanometers and deposit most of their energy between 100 - 110 kilometers where peak nitric oxide production occurs. Large flares can double the 0.1 - 2- and 0.1 - 7-nanometer daily integrated energy to the thermosphere, thus doubling the nitric oxide column density.
Major Professor: Dr. Dirk Lummerzheim

Thesis: Ecological and Social Influences on Population Dynamics and Genetics of Moose in Alaska
This dissertation explored the effects of ecological and social components on Alaskan moose population dynamics and genetics. With these two components, I explored catch-per-unit effort, antler size and population structure. I concluded that inclusion of ecological and social features greatly improves population dynamics and structure knowledge for moose in Alaska.
Major Professor: Dr. Kevin G. McCracken

Thesis: Circadian Rhythms, Neuroanatomy of the Suprachiasmatic Nucleus and Selective Breeding of the Northern Red-Backed Vole (Clethrionomys rutilus)
Daily rhythms of northern red-backed voles were found to be variable in constant light and dark. The mammalian master clock in the hypothalamus was investigated for common neurotransmitters and a few differences noted. An attempt was made to selectively breed voles with and without circadian rhythms in constant dark.
Major Professor: Dr. Abel Bult-Ito

Back to top