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Development Of A Laboratory Based System For Selecting Insect Pathogenic Fungi With Greatest Potential For Success In The Field, Chad Alton Keyser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many insects are important agricultural pests, and active control is necessary to keep them at abeyance. The naturally occurring entomopathogenic fungus Metarhizium is a promising tool to control pest insects, and its use avoids the well-known harmful side effects of chemical pesticides. Thousands of unique isolates of Metarhizium exist throughout the world. These isolates vary widely in their ability to cause infection and to tolerate stressful habitats. The research reported here tests the THESIS: A laboratory-based system can be devised that identifies, from among many Metarhizium isolates, those isolates with the greatest potential for successful biological control of pest insects …

Water Allocation Challenges In Rural River Basins: A Case Study From The Walawe River Basin, Sri Lanka, D. K. Neelanga Weragala

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation evaluates the water allocation challenges in the rural river basins of the developing world, where demands are growing and the supply is limited. While many of these basins have yet to reach the state of closure, their water users are already experiencing water shortages. Agricultural crop production in rural river basins of the developing world plays a major role in ensuring food security. However, irrigation as the major water consumer in these basins has low water use efficiency. As water scarcity grows, the need to maximize economic gains by reallocating water to more efficient uses becomes important. …

Cooperative Remote Sensing And Actuation Using Networked Unmanned Vehicles, Haiyang Chao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation focuses on how to design and employ networked unmanned vehicles for remote sensing and distributed control purposes in the current information-rich world. The target scenarios are environmental or agricultural applications such as river/reservoir surveillance, wind profiling measurement, and monitoring/control of chemical leaks, etc. AggieAir, a small and low-cost unmanned aircraft system, is designed based on the remote sensing requirements from environmental monitoring missions. The state estimation problem and the advanced lateral flight controller design problem are further attacked focusing on the small unmanned aerial vehicle (UAV) platform. Then the UAV-based remote sensing problem is focused with further flight …

Quantifying Legacy Effects Of Managed Disturbance On Sagebrush Steppe Resilience And Diversity, Julie Ripplinger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Land-use legacies can affect landscapes for decades to millennia. A long history of shrub management exists in the sagebrush steppe of the Intermountain West where shrub-removal treatments, a type of managed disturbance, have been implemented for over 50 years to reduce sagebrush cover. The assumption behind managed disturbances is that they will increase forage for domestic livestock and improve wildlife habitat. However, the long-term effects of managed disturbance on plant community composition and diversity are not well understood. We investigated the legacy effects of three common types of managed disturbance (chemical, fire, and mechanical treatments) on plant community diversity and …

Analysis Of Ammonia And Volatile Organic Amine Emissions In A Confined Poultry Facility, Hanh Hong Thi Dinh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The National Air Emission Monitoring Study (NAEMS) project was funded by the Agricultural Air Research Council (AARC) to evaluate agricultural emissions nationwide. Utah State University (USU) is conducting a parallel study on agricultural emissions at a Cache Valley poultry facility. As part of this parallel study, samples of animal feed, eggs and animal waste were collected weekly from three manure barns (designated: manure barn, barn 4 - manure belt and barn 5 - high rise) from May 2008 to November 2009.

These samples were analyzed to determine ammonia content, total Kjeldahl nitrogen content and ammonia emission. The yearly average calculated …

Fundamentals Of Operation Of The Induced Bed Reactor (Ibr) Anaerobic Digester, Jacob Shaun Dustin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Induced Bed Reactor (IBR) was developed at Utah State University to apply high-rate anaerobic digestion techniques to high solids content substrates. This technology has been successfully implemented at full-scale multiple installations in the United States and Canada as a waste treatment and energy production technology, but the physical processes necessary to further optimize the system were not well understood.

Bench scale IBRs were operated as anaerobic digesters at 35°, 45°, and 55° C under three organic loading rates and three corresponding hydraulic retention times. Reactor performance was monitored at steady state for residence time distribution and substrate reduction.

The …

Field And Smog Chamber Studies Of Agricultural Emissions And Reaction Products, Derek J. Price

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Agricultural emissions are an important contributor to atmospheric aerosol. These emissions include nitrogen containing organic compounds, primarily as amines, which have not been well investigated to date. Although there have been several studies that have looked at the emission of gas phase amines, there are only a few studies that have focused on ambient amine-based aerosol. There have also only been a handful of smog chamber studies that have investigated amine aerosol chemistry. Kinetic studies have looked at the reactions of amines with OH and ozone. However, amine reactions with nitrate radical (NO₃) are not well understood. Several …

Coyote Diet And Movements In Relation To Winter Recreation In Northwestern Wyoming: Implications For Lynx Conservation, Jennifer L. Burghardt Dowd

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Increased snowmobile use in mountainous terrain has been highlighted as a conservation concern for some Canada lynx (Lynx canadensis) populations. Snow compaction resulting from winter recreation may potentially facilitate access by coyotes (Canis latrans) to habitats used by lynx during winter. Increased interactions could result in either exploitation or interference competition between the two species. Two recent, yet geographically distinct, studies showed contrasting findings regarding coyote movements and their use of snow-compacted trails during the winter. These findings suggest coyote association with snow-compacted trails may be regionally specific and dependent upon ecosystem dynamics and snow characteristics. …

Our Mountain Home: The Oscar And Emma Swett Ranch, Carolyn Toone

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this thesis, I examined the lives of my great-grandparents, Oscar and Emma Swett. Oscar began a homestead in the Uinta Mountains in 1909, which he successfully ran for nearly sixty years. My grandmother was born on the ranch, and my own father spent much of his time there. I look at how land policy changed from encouraging ranching and farming in the early 1900's to tourism and recreation in the 1960's, with the coming of the Flaming Gorge Dam. The lives of my great-grandparents and their children were shaped by these changes and they felt the consequences of the …

"To Drink From Places": Uncovering A Rich Way Of Life Near The Grand Canyon's North Rim, Melinda Snow Rich

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The chapters of this thesis focus on the history and stories of the people who built and traveled down the highways--Highway 89A, Highway 89, and Highway 67--that branch out from the junction in front of Jacob Lake Inn, the Bowman/Rich family's 87-year-old lodge. The family's role in building roads, supporting and encouraging the growing tourist industry in Kanab and the North Rim of the Grand Canyon, and the converging effects of these choices have created the unique family culture and contributed to the history of the Grand Canyon region over time. Ultimately this thesis is about relationships, about the connections, …

Reproductive Ecology Of Astragalus Filipes, A Great Basin Restoration Legume, Kristal M. Watrous

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Astragalus filipes Torrey ex. A. Gray (Fabaceae) is being studied and propagated for use in rangeland restoration projects throughout the Great Basin. Restoration forbs often require sufficient pollination services for seed production and persistence in restoration sites. Knowledge of a plant's breeding biology is important in providing pollination for maximal seed set.

Reproductive output from four manual pollination treatments (autogamy, geitonogamy, xenogamy, and distant xenogamy) was examined in a common garden. Pod set, seed set, and seed germination were quantified for each of the treatments. Seed set from four wild populations was compared to that of an openly visited common …

History Steps Off The Page: The Past In The Future, A Case Study Of How The Mormon Battalion Is Making History Interactive, Allyson Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis addresses the presentation of the Mormon Battalion's history in three interactive forms. The Battalion served in the U.S.-Mexican War between 1846 and 1847. In 2008 a group known as Battalion Trek chose to rehike the original trail as closely as possible. The three chapters of this thesis address the reenactors who planned and completed the rehike, the blog they kept as they did so, and a program which allows those interested to learn more about the trail. Analyzing what such presentations have to offer is important as history moves into the hands of the public and as the …

Plastic And Genetic Determination Of Population, Community, And Ecosystem Properties In Freshwater Environments, Leigh C. Latta Iv

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The hierarchy of biological organization, from molecules to ecosystems, describes the relationships among various biological systems. Of particular interest is assessing how the factors that primarily determine the nature of one hierarchical level also have transcendent qualities that affect the ecology and evolution of higher hierarchical levels. The goal of this dissertation was to use a bottom-up approach to examine the transcendent effects of two factors that strongly determine the nature of their associated level of biological organization. The first, phenotypic plasticity, is a primary factor that determines the phenotype of an individual. The second factor, genetic diversity, largely determines …

Applying Information Visualization To Computer Security Applications, Robert Bruce Whitaker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents two phases of research in applying visualization to network security challenges. The first phase included discovering the most useful and powerful features in existing computer security visualizations and incorporating them into the AdviseAid visualization platform, an existing software package. The incorporation of such a complete feature set required novel resolution of software engineering, human factors, and computer graphics issues. We also designed additional novel features, such as plugin interfaces, allowing for rapid prototyping and experimentation with novel visualization features and capabilities. The second phase of the research focused on the development of novel visualization techniques themselves. These …

Stormwater Monitoring And Resident Behavior In A Semi-Arid Region, Jennifer Abraham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The combined effect of land-use alterations and introduced diffuse anthropogenic pollutants to the earth's surface in suburban/urban zones often sparks a decrease in stormwater quality in the area, and contributes to nonpoint source pollution in receiving waters. The ponds at the Utah Botanical Center (UBC) located in Kaysville, UT, regularly experience algal blooms, which in turn cause low dissolved oxygen levels in the waters, indicating high concentrations of inflowing pollutants. The goal of this thesis paper was to describe the findings from the water quality monitoring implemented at both the inlet and outlet of the UBC ponds in order to …

The Ability Of The Coping Competence Questionnaire To Predict Resilience Against Learned Helplessness Among Undergraduate College Students: An Experimental Study, Cindy L. Ollis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Coping Competence Questionnaire (CCQ), based on the reformulated learned helplessness theory, was designed to assess a general stress resistance versus a propensity towards learned helplessness with a brief, 12-item self-report questionnaire. In this study the CCQ was administered to 247 undergraduate students, who were then paired, in groups of around 24 at a time, and then randomly assigned to either success or failure conditions on the computer game TetraVex. Mood was pretested using the Profile of Mood States (POMS) depression subscale; the experimental condition, success or failure at TetraVex was conducted; then outcome measures including 20 five letter anagrams …

Transesterification And Recovery Of Intracellular Lipids Using A Single Step Reactive Extraction, Daniel R. Nelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A single-step, extractive reaction for extraction of lipids such as biodiesel components, omega-3 fatty acids, or other triglycerides from microbial cells was examined. Conventional methods for lipid extraction use toxic solvents, and require multiple steps and long processing times. When the goal is to produce fatty acid methyl esters or FAMEs, the extracted lipids are subjected to a separate transesterification reaction with simple alcohols in the presence of an acid or base catalyst. A simplified, single-step reactive extraction method can be applied that combines the sequential extraction followed by transesterification using acidified alcohols - a process known as in situ …

Development Of An Innovative Statewide Population Monitoring Program For Mule Deer, Heather H. Bernales

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Monitoring population trend and estimating vital demographic parameters are essential for effective management of a mule deer (Odocoileus hemionus) population. Because of financial constraints, many wildlife agencies use computer models to obtain indirect indices of population size and trend as an alternative to annual field-based estimates of population size. These models are based primarily on herd composition counts and harvest rates from hunter-harvest surveys, and are rarely field validated. I developed an alternative method for monitoring population dynamics of wintering populations of mule deer. I designed a hybrid monitoring program that combined annual vital rate monitoring to track changes in …

Changes In Hybrid Poplar Endophytic Microbial Diversity In Response To Trichloroethylene Exposure, Jared S. Ervin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Remediation of trichloroethylene (TCE) is a major priority for many contaminated sites all over the industrialized world including Hill Air Force Base, UT (HAFB). Phytoremediation as part of a cleanup strategy is an appealing option, and trees at HAFB have been studied to this end. Trees have also been used to delineate groundwater plumes because the passive uptake of organic contaminants by trees generally results in a direct relationship between tree and groundwater TCE concentrations if the trees are using the contaminated groundwater. However, the concentrations of plant-produced TCE metabolites can vary greatly. It was hypothesized that the endophytic microbial …

Decentralized Coordination Of Multiple Autonomous Vehicles, Yongcan Cao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation focuses on the study of decentralized coordination algorithms of multiple autonomous vehicles. Here, the term decentralized coordination is used to refer to the behavior that a group of vehicles reaches the desired group behavior via local interaction. Research is conducted towards designing and analyzing distributed coordination algorithms to achieve desired group behavior in the presence of none, one, and multiple group reference states.

Decentralized coordination in the absence of any group reference state is a very active research topic in the systems and controls society. We first focus on studying decentralized coordination problems for both single-integrator kinematics and …

Comparative Ecology Of Narrowly Sympatric Horned Lizards Under Variable Climatic Conditions, Kevin V. Young

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We studied the Flat-tailed Horned Lizard, Phrynosoma mcallii, and the Sonoran Horned Lizard, P. goodei, in an area of narrow sympatry near Yuma, Arizona, and found they overlapped broadly in use of available food resources, body size, and growth rates. We compared diet (Chapter 2), growth and reproduction (Chapter 3), and survivorship (Chapter 4) of P. mcallii and P. goodei during two years of drought followed by a year of higher-than-average rainfall. We predicted that P. mcallii would be more tolerant of drought conditions than its congener, since P. mcalliiis found only in an extremely arid region while …

Maternal Effects In Transmission Of Self-Medicative Behavior From Mother To Offspring In Sheep, Udita Sanga

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mammals begin learning food preferences in utero and maternally mediated influences early in life help offspring develop their feeding habits. Mammals also learn by individual experience to ingest medicinal compounds such as polyethylene glycol (PEG), which attenuates the negative post-ingestive effects of tannins, a group of potentially toxic plant secondary compounds. The objective of this study was to investigate the transmission of acquired self-medicative behavior from mother to offspring using polyethylene glycol (PEG) as a medicine to relieve malaise caused by tannins. I hypothesized that: 1) mothers trained to associate the beneficial effects of PEG while consuming tannins will pass …

Object-Based Segmentation And Classification Of One Meter Imagery For Use In Forest Management Plans, W. Kevin Wells

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research developed an ArcGIS Python model that extracts polygons from aerial imagery and assigns each polygon a vegetation type based on a modified set of landcover classes from the Southwest Regional Gap Analysis Project. The model showed an ability to generate polygons that accurately represent vegetation community boundaries across a large landscape. The model is for use by the Utah Division of Forestry, Fire, and State Lands to assist in the preparation of forest management plans. The model was judged useful because it was easy to use, it met a designated 50% threshold of useable polygons, and it met …

Terrestrial Ecosystem Classification In The Rocky Mountains, Northern Utah, Antonin Kusbach

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Currently, there is no comprehensive terrestrial ecosystem classification for the central Rocky Mountains of the United States. A comprehensive classification of terrestrial ecosystems in a mountainous study area in northern Utah was developed incorporating direct gradient analysis, spatial hierarchy theory, the zonal concept, and concepts of diagnostic species and fidelity, together with the biogeoclimatic ecosystem classification approach used in British Columbia, Canada.

This classification was derived from vegetation and environmental sampling of both forest and non-forest ecosystems. The SNOwpack TELemetry (SNOTEL) and The National Weather Service (NWS) Cooperative Observer Program (COOP) weather station network were used to approximate climate of …

Parents As Partners In Kindergarten And Second Grade Literacy Instruction: A Qualitative Inquiry Into Student-Authored Traveling Books, Dorothy C. Little

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to study a sociocognitive “student/parent/peer authoring community” called Traveling Books (TBks) in kindergarten and second grade in a public elementary school setting. TBks are teacher-made vehicles for involving parents in peer-based literacy environments. The study was based on Epstein's theory that increasing overlap of students' spheres of influence, home, school, and community, creates a greater likelihood that children will learn what the parents want them to learn. The aim was to locate essential elements that triggered learning processes to occur and to discover research-based fundamentals still missing from TBks.

This qualitative inquiry incorporated the …

A Multi-Scale Evaluation Of Pygmy Rabbit Space Use In A Managed Landscape, Tammy L. Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Habitat selection has long been viewed as a multi-scale process. Observed species responses to resource gradients are influenced by variation at the scale of the individual, population, metapopulation, and geographic range. Understanding how species interact with habitat at multiple levels presents a complete picture of an organism and is necessary for conservation of endangered species. The main goal of this dissertation is to evaluate distribution, relative abundance, and habitat selection of a rare species, the pygmy rabbit Brachylagus idahoensis, at multiple scales in order to improve management and conservation for this species.

At the broadest scale, pygmy rabbit occurrence …

Greater Sage-Grouse Seasonal Ecology And Responses To Habitat Manipulations In Northern, Utah, Eric T. Thacker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Declining greater sage-grouse populations (Centrocercus urophasianus; hereafter sage-grouse) have led to increased concern regarding the long-term stability of the species. Previous research has identified factors contributing to the observed population declines. Habitat degradation and loss have been implicated as major factors in population declines. Although much is known about sage-grouse biology, more information is needed about population responses to specific management actions. This research was conducted to document sage-grouse responses to site-specific management actions. Additionally, I evaluated sage-grouse temporal and seasonal habitat-use and the comparability of techniques used by range and wildlife managers to measure vegetation responses of …

Nutrient Utilization From Anaerobic Digester Effluent Through Algae Cultivation, Shantanu Wahal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nutrients present in digested animal waste can be utilized for algae cultivation under suitable conditions. Algal growth, however, depends on the chemical forms and speciation of these nutrients. In this study a chemical equilibrium model was first used to describe nutrient speciation and predict conditions that enhance the solubility of nutrients in anaerobic digester effluent. Dilution with water and separation of large particulates greatly improved nutrient availability and light penetration - conditions favorable for algal cultivation. Algae growth was tested using three strains - Scenedesmus dimorphous (UTEX # 417), Chlorella vulgaris (UTEX# 265), and an algal isolate (designated as LLAI …

Greater Sage-Grouse Response To Sagebrush Reduction Treatments In Rich County, Utah, Roger Blair Stringham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Management of greater sage-grouse (Centrocercus urophasianus) in the west has changed over the last several decades in response to environmental and anthropogenic causes. Many land and wildlife management agencies have begun manipulating sagebrush with herbicides, machinery, and fire. The intent of these manipulations (treatments) is to reduce sagebrush canopy cover and increase the density of grass and forb species, thus providing higher quality sage-grouse brood-rearing habitat. However, monitoring of sage-grouse response to such manipulations has often been lacking or non-existent. The objective of our study was to determine the response of sage-grouse to sagebrush reduction treatments that have …

Ecology Of Isolated Greater Sage-Grouse Populations Inhabiting The Wildcat Knolls And Horn Mountain, Southcentral Utah, Christopher J. Perkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Greater sage-grouse (Centrocercus urophasianus) currently inhabit about 56% of pre-settlement distribution of potential habitat. In 2005, the Castle Country Adaptive Resources Management Local Working Group (CaCoARM) was formed to address concerns regarding local sage-grouse populations in Carbon and Emery counties. In 2006-2007, CaCoARM identified the Wildcat Knolls and Horn Mountain as areas of special concern for greater sage-grouse conservation. Both sites selected by the group were inhabited by what appeared to be small isolated sage-grouse populations. Factors limiting small isolated greater sage-grouse populations throughout its range are diverse and largely site-specific.

During 2008-2009, I captured, radio-collared, and monitored …