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Assessing Stream Channel Restoration: The Phased Recovery Framework, Jacob M. Dyste Jan 2017

Assessing Stream Channel Restoration: The Phased Recovery Framework, Jacob M. Dyste

Graduate Student Theses, Dissertations, & Professional Papers

Channel reconfiguration projects command a large portion of stream restoration resources, while long-term monitoring and research is severely underfunded and rarely implemented. This has led to a limited knowledge base about ecological response and efficacy. Although channel reconfiguration projects are being implemented to restore biological function to lotic systems, the document responses are highly variable and little evidence has shown these projects are reaching their target goals. I predicted the inconsistent response to these projects is the result of disturbance-induced successional processes and catchment-scale water quality impairment. To address how these endogenous and exogenous factors influence stream response to channel …


Drivers And Feedbacks Of The Fire-Grazing Interaction In The Northern Great Plains, Jacob E. Powell Jan 2017

Drivers And Feedbacks Of The Fire-Grazing Interaction In The Northern Great Plains, Jacob E. Powell

Graduate Student Theses, Dissertations, & Professional Papers

The fire-grazing interaction is well studied in mesic grasslands worldwide, but research is lacking in semiarid systems. In addition, the fire-grazing interaction reduces the invasion of exotic forage species in mesic grasslands by increasing the scale of grazing selection and may be a tool to control invasive plants in other grasslands. We examined the principal drivers and feedbacks of the fire-grazing interaction on the strength of cattle grazing selection, forage quantity and quality, and vegetation structure and composition in two pastures in northeast Montana at The Nature Conservancy’s Matador Ranch. We also determined the influence of time since fire, within …


Harvest And Persistence Of Wolf Populations: Variable Effects Of Harvest On Wolf Packs In The Rocky Mountains, Sarah B. Bassing Jan 2017

Harvest And Persistence Of Wolf Populations: Variable Effects Of Harvest On Wolf Packs In The Rocky Mountains, Sarah B. Bassing

Graduate Student Theses, Dissertations, & Professional Papers

Pubic harvest is a common method used to manage populations of wolves (Canis lupus) in North America. Although wolves appear resilient to the effects of harvest management the influences on demography and pack stability are uncertain. Packs generally drive population dynamics for wolves; thus, we were interested in how harvested populations were maintained and how harvest influenced the abundance and distribution of packs. We used noninvasive genetic data collected in Idaho, USA (2008–2014) and Alberta, Canada (2012–2014) to test whether immigration compensated for harvest mortality and helped maintain population densities. We further fit occupancy models to detection data …


Coupling Biophysical Complexity And Forest Metabolism In A Floodplain Landscape, Peter Davis Jan 2017

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 …


Response Of Amphibian And Invertebrate Communities To Wetland Mitigation In The Greater Yellowstone Ecosystem, Leah K. Swartz Jan 2017

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 …


Contributions Of Gene Copy Number Variation To Genome Evolution And Local Adaptation Of The Cyanobacterium Acaryochloris, Amy L. Gallagher Jan 2017

Contributions Of Gene Copy Number Variation To Genome Evolution And Local Adaptation Of The Cyanobacterium Acaryochloris, Amy L. Gallagher

Graduate Student Theses, Dissertations, & Professional Papers

Acaryochloris is a recently discovered genus of cyanobacteria, unique in its use of an uncommon chlorophyll as its major photosynthetic pigment, and in its peculiar genome dynamics. Members of this genus exhibit increased genic copy number variation (CNV), which is thought to be primarily derived from gene duplications and horizontal gene transfer (HGT). Acaryochloris provides an ideal system to explore mechanisms behind maintenance of gene duplicates and the influence of CNV in local adaptation. Here, I propose a mechanism for retention of gene duplicates of the bacterial recombinase, RecA, in Acaryochloris genomes and provide preliminary evidence that these paralogs are …


Evolution Of Molt Phenology In Dwarf Hamsters, Zachary Clare-Salzler Jan 2017

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 Jan 2017

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 …


Understanding Patterns And Drivers Of Alaskan Fire-Regime Variability Across Spatial And Temporal Scales, Tyler J. Hoecker Jan 2017

Understanding Patterns And Drivers Of Alaskan Fire-Regime Variability Across Spatial And Temporal Scales, Tyler J. Hoecker

Graduate Student Theses, Dissertations, & Professional Papers

Boreal forest and tundra ecosystems are globally important because the mobilization of large carbon stocks, and changes in energy balance could act as positive feedbacks to ongoing climate warming. In Alaska, wildfire is a key driver of ecosystem structure and function, and therefore fire strongly determines the feedbacks between high-latitude ecosystems and the larger Earth system. The paleoecological record from Alaska reveals the sensitivity of fire regimes to climatic and vegetation change over centennial to millennial time scales, highlighting increased burning with warming and/or increased landscape flammability associated with large-scale vegetation changes. This thesis focuses on two studies aimed at …


High-Resolution Mapping Of Hierarchical Greater Sage-Grouse Nesting Habitat: A Grain-Spectrum Approach In Northwestern Wyoming, Robert T. Haynam Iii Jan 2017

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 …


¬Multilocus Phylogeny Of The Lichen Family Megasporaceae, Tim B. Wheeler Jan 2017

¬Multilocus Phylogeny Of The Lichen Family Megasporaceae, Tim B. Wheeler

Graduate Student Theses, Dissertations, & Professional Papers

The lichen symbiosis is one of the oldest studied mutualisms; in fact, Frank and De Bary coined the term "symbiosis" while studying lichens (Frank, 1877; De Bary 1879). The widespread, stable association between the mycobiont and photobiont in lichens offers an ideal system for the study of co-evolution. The recent application of molecular data to lichens has begun to unveil the complexities involved in these associations (Upreti et al. 2015, Spribille et al. 2016). Lichenized fungi make up a huge fraction of fungal diversity (Nash 2008), yet very little is known of their genetic diversity. Fungal taxonomy is notoriously difficult …


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 Jan 2017

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, …