Life Sciences Commons^™

An Assessment Of How Plant And Mycorrhizal Communities Have Been Affected Along A Mine-Impacted Watershed In The Northwest Territories, Kevin Maccoll

Theses and Dissertations (Comprehensive)

Giant Mine is an inactive gold mine located nine kilometers north of Yellowknife, Northwest Territories. Giant Mine has been the source of arsenic trioxide for the Baker Creek watershed since it opened over 60 years ago. Although arsenic levels in the creek are above the limits considered to be biologically relevant, there is no concrete evidence that plants and mycorrhizae have actually been affected. This study provides an initial assessment of the impacts mining activity at Giant Mine has had on plants and mycorrhizae in the Baker Creek watershed. Nine sites were sampled around Giant Mine: five sites downstream from …

Behavioral Ecology Of An Invasive Species: Habitat And Mate Preference(S) In Drosophila Suzukii, Yvonne Young, Natasha Buckiewicz, Tristan Af Long Dr.

Theses and Dissertations (Comprehensive)

The invasive Spotted-Wing fruit fly, Drosophila suzukii, has inflicted substantial economic losses to the soft-fruit agriculture industry worldwide due to the ability of females in this species to use a large, serrated ovipositor to cut the fruit’s skin and lay eggs directly into the mesocarp of ripening fruit. Once the eggs hatch, larvae consume the fruit flesh, ultimately leaving the fruit unmarketable. This species parasitizes numerous commercial fruit types (including blueberries, blackberries, strawberries, raspberries and occasionally grapes) as well as fruits from a variety of wild plant species. Since fruit types vary in their nutritional composition, as well as their …

Effects Of Wildfires On Tree Establishment In Conifer-Dominated Boreal Forests In Southern Northwest Territories, Kirsten Reid

Theses and Dissertations (Comprehensive)

Black spruce (Picea mariana) and jack pine (Pinus banksiana) both release a large majority of their seeds after fire and thus experience large pulses of recruitment during these punctuated events. Global warming is driving intensification of the wildfire regime in the boreal forest, which is resulting in shifts from coniferous to deciduous dominated forests in some parts of the boreal forest of North America. This shift can present consequences for forest structure, ecosystem dynamics, carbon cycling, and wildlife habitat.

During 2014, the Northwest Territories experienced a historically unprecedented fire year with 3.4 million hectares of forest …

Influence Of Topography And Moisture And Nutrient Availability On Green Alder Function On The Low Arctic Tundra, Nt, Katherine Louise Black Ms., Jennifer Lynn Baltzer Dr.

Theses and Dissertations (Comprehensive)

The Arctic has warmed by at least 3^°C over the past 50 years and this rapid warming is expected to continue. Climate warming is driving the proliferation of shrubs across the tundra biome with implications for energy balance, climate, hydrology, nutrient cycling, and biodiversity. Changes in tundra plant water use attributable to shrub expansion are predicted to increase evapotranspirative water loss which may amplify local warming and reduce run-off. However, little is known about the extent to which shrubs will enhance evapotranspirative water loss in these systems. Direct measures of shrub water use are needed to accurately predict …

Evolution Of Molt Phenology In Dwarf Hamsters, Zachary Clare-Salzler

Graduate Student Theses, Dissertations, & Professional Papers

Environmental seasonality presents many challenges for survival. In response, organisms from across the tree of life exhibit adaptive phenology, which can facilitate survival from season to season. In particular, many species are white in the winter and brown in the summer where winter snow cover alters the visual environment. There is an extensive body of literature describing the physiological and cellular regulation of this trait in the Siberian dwarf hamster (Phodopus sungorus), but there are major shortcomings in our understanding concerning the evolution and molecular regulation of mammalian skin phenology. Notably, little is known about the genetic basis …

K-Mer Analysis Pipeline For Classification Of Dna Sequences From Metagenomic Samples, Russell Kaehler

Graduate Student Theses, Dissertations, & Professional Papers

Biological sequence datasets are increasing at a prodigious rate. The volume of data in these datasets surpasses what is observed in many other fields of science. New developments wherein metagenomic DNA from complex bacterial communities is recovered and sequenced are producing a new kind of data known as metagenomic data, which is comprised of DNA fragments from many genomes. Developing a utility to analyze such metagenomic data and predict the sample class from which it originated has many possible implications for ecological and medical applications. Within this document is a description of a series of analytical techniques used to process …

Coupling Biophysical Complexity And Forest Metabolism In A Floodplain Landscape, Peter Davis

Graduate Student Theses, Dissertations, & Professional Papers

Floodplains are biophysically complex systems that are considered among the most productive and biodiverse ecosystems on Earth. Until recently, quantitative assessment of the relationship between complexity and terrestrial production has been constrained by technological limitation. To address how floodplain biophysical complexity and ecosystem function are related, I employed remote sensing, GIS, and spatial analyses to quantify and couple metrics of complexity and terrestrial production, as well as explore the relationship among complexity, vegetation structural diversity, and terrestrial primary productivity. The study site is a 6.75-km by 1.75-km portion of the Bitterroot River floodplain near Carlton, MT upon which 551 sample …

High-Resolution Mapping Of Hierarchical Greater Sage-Grouse Nesting Habitat: A Grain-Spectrum Approach In Northwestern Wyoming, Robert T. Haynam Iii

Graduate Student Theses, Dissertations, & Professional Papers

Our overall objective was to create a probabilistic nesting-habitat map for the Jackson Hole sage-grouse population that would have utility as a tool for future research, conservation, and management. The models that we developed for this purpose were specified to evaluate whether sage-grouse may be selecting nesting-habitat characteristics simultaneously at various spatial scales. Our spatially-explicit landscape-scale research was implemented primarily with readily available National Agriculture Imagery Program (NAIP) data. All nesting data was collected from 2007-2010. We tested how a broad range of grain sizes (spatial resolution) of covariate values affected the fit to logistic regression models used to estimate …

Limited Evidence For Co2-Related Growth Enhancement In Northern Rocky Mountain Pinus Contorta Populations: Trends In Growth And Intrinsic Water-Use Efficiency Across Climate Gradients, Charlotte C. Reed

Graduate Student Theses, Dissertations, & Professional Papers

Forests sequester large amounts of carbon annually; however, the degree to which enhanced forest productivity is due to more conducive climate or CO₂ fertilization remains uncertain. Increasing atmospheric CO₂ may enhance photosynthesis and/or decrease stomatal conductance thereby enhancing intrinsic water use efficiency (iWUE). While increasing iWUE has been observed in most trees globally, this increase does not necessarily translate into greater growth. This study aims to evaluate whether responses of radial growth and iWUE to increasing CO₂ vary across climatic gradients. To investigate interactions between climate and CO₂ and their impacts on tree physiology and growth, …

Response Of Amphibian And Invertebrate Communities To Wetland Mitigation In The Greater Yellowstone Ecosystem, Leah K. Swartz

Graduate Student Theses, Dissertations, & Professional Papers

Wetlands play a critical role in supporting freshwater biodiversity and ecosystem services, but human activities have resulted in large-scale loss and degradation of these habitats across the globe. To offset the decline of wetland area, mitigation wetlands are now frequently constructed, but their ability to replace the functions of natural habitats, including providing habitat for native fauna, remains uncertain. A recent highway reconstruction project in northwestern Wyoming caused impacts to and the destruction of multiple natural wetlands. To mitigate this loss, new wetlands were constructed along the highway corridor. To evaluate the performance of these created wetlands relative to reference …

Rmalpinecoverdata.Pdf, George P. Malanson

George P Malanson

Westalpinespecies.Pdf, George P. Malanson

George P Malanson

No abstract provided.

Genomic Plasticity And Rapid Host Switching Can Promote The Evolution Of Generalism: A Case Study In The Zoonotic Pathogen Campylobacter, Dan J. Woodcock, Peter Krusche, Norval J. C. Strachan, Ken J. Forbes, Frederick M. Cohan, Guillaume Meric, Samuel K. Sheppard

Frederick M. Cohan

Assessing The Diversity And Composition Of Spiders In The Lancer Park Flood Plain, William Kish, Sujan Henkanaththegedra

William Kish

Ecotone Response To Climatic Variability Depends On Stress Gradient Interactions, George P. Malanson

George P Malanson

No abstract provided.

Natural History Note: Snapping Turtle Behavior, Beth Reinke, David Klinges

Beth Reinke

No abstract provided.