Life Sciences Commons^™

Assessing Post-Fire Revegetation Efforts In Box Elder County, Utah, Using The Rangeland Analysis Platform, Rayce Bryan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

After fires occur in western rangelands, land management agencies commonly perform vegetation treatments and reseeding projects. The West Box Elder Coordinated Resource Management Group expressed concern regarding the difficult process of determining outcomes from the many post-fire revegetation projects undertaken on rangeland of Box Elder County, Utah. This research attempted to compile and clarify the fire and treatment history of the county and produce an assessment of the outcomes from each unique post-fire treatment in West Box Elder County. Also produced was a database of post-fire revegetation outcomes in published literature.

Unique treatment polygons were identified and then subset according …

Approaches To Supplementing Silicon In Soilless Media And The Value Of Silicon In The Mitigation Of Drought Stress, Mackenzie Grace Dey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Silicon (Si) is not considered an essential element for plants to complete their lifecycle, but is known to be beneficial for plants under environmental stress such as drought. Unlike natural soils, Si is minimally bioavailable in soilless media. With indoor agriculture and greenhouse production increasing, the benefits of Si have been seen and Si should be supplemented. This work aimed to characterize and quantify the dissolution of Si from media substrates and additives to achieve a steady-state release of Si in soilless media. Typical media components such as coconut coir, peat moss, perlite, rock wool, sand, and vermiculite minimally released …

Evaluating Strategies For Anemone And Ranunculus Cut Flower Production In The Us Intermountain West, Shannon Rauter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

National growth in small-scale, specialty cut flower farms is reflected in Utah, where 145 members have joined the Utah Cut Flower Farm Association since its 2019 founding. Cool season cut flower production is limited in Utah and the Intermountain West by a narrow harvest window and elevated soil salinity. The objective of this research was to optimize production systems for anemone (Anemone coronaria L.) and ranunculus (Ranunculus asiaticus L.) in the Intermountain West by evaluating season advancement methods within a high tunnel and field production system, as well as the salinity sensitivity of each species. Fall planting dates, …

Spatial-Temporal Responses Of Cow Elk To Targeted And Non-Targeted Hunting Risk, Randall Mcbride

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Predation is one of the most important interspecies interactions that affect a wildlife population. Predator-prey interactions may cause species to shift their behavior, such as changing the use of their habitat in both space and time, based on their ability to assess risk. Wildlife population responses to predation stresses have been studied in the past, but individuals' responses to these stresses have not been studied in fine detail. For this study, cow elk were collared with GPS collars, and hunters carried hand-held GPS units. GPS locations were taken at 10-minute intervals for both cow elk and hunters during the hunting …

Impacts Of The Changing Pacific On North American Drought, Atmospheric Rivers, And Explosive Cyclones, Jacob Stuivenvolt-Allen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The impacts of specific weather events can vary greatly from year to year. Much of these impacts depend heavily on the frequency of impactful weather which is constrained by the state of the climate system each year. This research focuses largely on the impacts that climate oscillations from year-to-year or even from decade-to-decade have on the frequency of impactful weather. There are numerous examples of impactful weather that impact North America, but this work focuses on drought in the western United States, atmospheric rivers in Northern California and rapidly developing winter storms along the east coast. While seemingly disparate events, …

Investigating Cause-Specific Mortality Of Sheep To Determine The Impacts Of Carnivores On Domestic Livestock, Nathan Jacob Floyd

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Livestock and carnivores interact in ways that are considered conflict throughout the world. In the western United States, livestock are often grazed on public lands in close proximity to predators in their natural habitat, and can be killed as prey. Livestock losses to predators can threaten rancher’s livelihoods. Sheep and lambs are especially vulnerable to predators due to their small size and lack of defensive abilities. To reduce the impacts that predators have on livestock, it is important for ranchers and wildlife biologists to have an accurate understanding of how many livestock die and are killed by predators when grazing …

Management Of Garlic Mustard (Alliaria Petiolata), Sahara Mustard (Brassica Tournefortii), And Elongated Mustard (Brassica Elongata) In Utah, Natalie Layne Fronk

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The invasive mustard species Sahara mustard (Brassica tournefortii), garlic mustard (Alliaria petiolata) and elongated mustard (Brassica elongata) negatively impact a variety of ecological systems across the state of Utah. The distribution of these species in Utah is relatively limited at the current time. If prompt action is taken, it may be possible to contain and manage these species before irreparable ecological and agricultural damage occurs. For this reason, all three mustards are listed by the State of Utah as weeds of high priority for management.

This project tested multiple strategies to determine effective species-specific …

Quantification Of Hydrologic Response To Forest Disturbance In Western U.S. Watersheds, Sara A. Goeking

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Forested watersheds produce more than half of the water supply in the United States. Forests affect how precipitation is partitioned into available water versus evapotranspiration. This dissertation investigated how water yield and snowpack responded to forest disturbance following recent disturbances in western U.S. forests during the period 2000-2019.

Chapter 2 systematically reviewed 78 recent studies that examined how water yield or snowpack changed after forest disturbances. Water yield and snowpack often increased after disturbance, but decreased in some circumstances. Decreased water yield was most likely to occur following disturbances that did not remove the entire forest canopy. It was also …

Dairy Breed, Grass-Birdsfoot Trefoil Mixture, And Pasture Nutrition Effects On Intake, Feed Efficiency, And Grazing Adaptation, Michael Greenland

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dairy cattle have lower dry matter intake (DMI) on pastures thus leading to less weight gain and milk production than feedlot cows. This study was conducted to determine whether different dairy breeds are better adapted to lower or higher quality pastures as measured in DMI and feed efficiency. The eight treatments consisted of Jersey, Holstein, Holstein-Jersey crossbreds, and 3-breed crossbreds (Montbéliarde-Swedish Red-Holstein) heifers on grass monocultures and grass-BFT mixtures. We observed greater DMI on grass-BFT mixtures. Among breeds, Holstein had the greatest DMI, then the two crossbreds, and Jersey had the least. Feed efficiency was most favorable for Jersey, less …

An Evaluation Of Landscape, Climate, And Management Impacts On Bumble Bees (Hymenoptera: Apidae: Bombus) In Agroecosystems, Morgan Elizabeth Christman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bumble bees play pivotal roles in pollinating wild and cultivated plant communities. Unfortunately, bumble bee populations are declining due to disturbances such as landscape conversion and climate change. Additionally, traps used to monitor pest insect populations often capture bumble bees, leading to a concern that trap captures increase bumble bee mortality. First, I studied bumble bee communities based on land cover and weather variables in agricultural fields in Utah. Bumble bee communities were more diverse in agricultural fields with more agricultural land in the surrounding area, low temperatures, and high humidity during the growing season, and less diverse in fields …

Soil Genesis Across A Climo-Lithosequence Of Western Haleakalā, Maui, Ryan C. Hodges

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The soils of western Haleakalā are incredibly diverse due to two primary reasons: 1) they receive varying levels of rainfall based on location relative to Haleakalā, and 2) volcanic vents upwind of the area indicate that volcanic ash has blanketed much of western Haleakalā in the past. Ash can weather to form short-range-order materials, which contribute to the classification of andic soil properties. Due to their structure, short-range-order materials impart soil behavior that creates benefits and challenges in land management. Therefore, an understanding of how these soils formed and differ, and where andic soils occur is crucial.

The objectives of …

Skeletal Muscle Growth Of Beef Cattle: Cattle Breed Types And Anabolic Implants, Caleb C. Reichhardt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two potential methods that can be used by the U.S. to help further improve environmental and economic sustainability of the beef industry are through the use anabolic implants, typically composed of the hormones estradiol and trenbolone acetate, and by crossbreeding Bos taurus and Bos indicus cattle. How anabolic implants operate to improve growth, and their resulting relationship with different cattle breed types have yet to be determined. However, crossbreeding these cattle breed types has been found to have a positive influence on economically important traits such as average daily gain and carcass characteristics. Therefore, we hypothesized that the different hormones …

Evaluating Microbial Safety Of Food Products And Processes In Small Scale Food Services, Processors And Manufacturers, Sujan Acharya

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study evaluated microbial safety of relatively new and modified food products prepared especially by small-scale foodservice establishments and home producers. In the first part, microbial safety during fermentation at room temperature was evaluated. Chapter 3 monitored Listeria monocytogenes and Escherichia coli O157 survival during Sauerkraut’s natural fermentation. Chapter 4 evaluated the survival of acid-adapted E.coli O157 during kombucha fermentation and in kombucha-fruit blend during refrigeration. During both fermentations, the pathogens were inactivated before the recommended duration of fermentation. However, E.coli O157 introduced after fermentation survived in kombucha-fruit blends during refrigerated storage. The second part (Chapter 5) evaluated the safety …

Biodiversity And Foraging Preferences Of Bee Communities At Pinnacles National Park Over Time, Abigail M. E. Lehner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bees are considered to be the most important animal pollinator, providing billions of dollars in pollination services each year. Despite their importance in both natural and agricultural settings, the status of most native bees is unknown. Native bees are subject to a variety of threats including habitat loss, pesticide use, and climate change. Yet, monitoring programs have been implemented in few natural areas. Pinnacles National Park, PNP, in California is one of the only natural areas to have a large historical dataset on bees across decades with surveys conducted in 1996, 1997, 1998, 1999, 2002, 2011, and 2012. These surveys …

Using Cytoplasmic Biopsies To Determine Bovine Oocyte Quality, Madison Lindsey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Embryos resulting from assisted reproductive technologies, such as in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI), develop with lower efficiencies than embryos resulting from their in vivo counterparts. The reasons behind the developmental discrepancies remain largely unknown. Because the egg is the primary determinant of embryo developmental success, it is reasonable to consider inherent egg quality as a possible cause. The hypothesis for this project is that there are distinct mRNA transcript patterns, or molecular “fingerprints,” that distinguish high- versus low-quality eggs developing within the same environment. In this study, a small cytoplasmic biopsy was removed from 40 eggs …

Natural History And Development Of Melittobia Acasta On Megachile Rotunda , Alan R. Anderson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Alfalfa is one of the most economically important crops in North America. To produce alfalfa seed, a pollinator must release plant reproductive organs by applying pressure to keel petals. The alfalfa leafcutting bee, Megachile rotundata, is the primary commercial pollinator of alfalfa. U.S. bee managers struggle to maintain populations due to many mortality factors. One cause is attack from parasitoid wasps such as Melittobia acasta. Females can lay hundreds of eggs and have multiple generations, which can decimate bee stocks. Chapter Two investigates the life cycle and base temperature that allows development of M. acasta on bee hosts. …

Maternal Effects And Management Of Alfalfa Leafcutting Bees, Makenna May Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Most bees are solitary and important contributors to pollination of a variety of crops. Solitary bees do not live in colonies. Instead, females work individually to construct nests and provision nutrients for each offspring. However, solitary bees can be difficult to manage, especially on a large scale like honey bees, because of differences in how species provision for their offspring and construct nests. Variations in the timing of offspring development to adulthood even within species makes commercial management difficult. Variations in reproductive strategy, like how many offspring to make, how much provision to give each, and when to make them …

Evaluation Of Noninvasive Methods For Determining Pregnancy, Diet, Nutrition, And Stress Among Pronghorn Antelope: Implications For Population Monitoring, Cole Bleke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted to increase our understanding of the influence of adult female pronghorn (Antilocapra americana) physiology on fawn summer survival. Pronghorn are a valued big game animal in Idaho, but are particularly sensitive to capture; therefore, we designed a noninvasive fecal sampling study to measure pregnancy (progesterone and estrogen), diet, nutrition (fecal nitrogen and DAPA), and stress (cortisol), during metabolically-demanding female life history stages (late gestation, early lactation, and breeding season). We also compared survey results between ground and aerial methods within mountain valley landscapes.

Pregnancy determination, via progesterone, is possible for pronghorn, but sample collection …

Hidden Mechanisms Of Climate Impacts In Western Forests: Integrating Theory And Observation For Climate Adaptation, Sara J. Germain

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fire, insects, and disease are necessary components of forest ecosystems. Yet, climate change is intensifying these tree stressors and creating new interactions that threaten forest survival. This dissertation combined field observations with statistical predictions of changing disturbances in western forests to identify 1) how conventional models may underestimate future forest loss, and 2) how positive relationships between trees may be exploited by managers to prevent forest loss.

In Chapter II, I tested whether increasingly extreme weather with climate change increases Pacific yew extinction risk. I found that conventional modeling methods underestimated local extinction risk because trees were adapted to a …

Finding Relationships Between Physical Properties Of Butter And Water Loss, Annalisa Jones

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Butter is a desirable fat rich product used for laminated pastries, like croissants, because of its flavor and consumer acceptance. However, butter has some functional aspects that reduce its performance and quality. In manufacturing of butter for laminated pastries, large blocks of butter are pushed through a rectangular opening to form a thin sheet. In this process it is not unusual to see water dripping, indicating water loss in the butter. The purpose of this study was to understand the properties of butter and their role in water loss during processing.

The properties of commercial butters were tested to understand …

Comparing Fecal Dna Capture-Recapture Methods To Traditional Mark-Resight Methods For Estimating Abundance Of Mule Deer On Winter Ranges, Andi M. Stewart

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Well-designed monitoring strategies are required to obtain accurate estimates of population abundance, which is important for evaluating conservation and management strategies. Obtaining abundance estimates using traditional survey methods, like aerial surveys, is not possible in all scenarios and can be expensive and risky. One survey method that has gained popularity in the last decade is fecal DNA-based capture-recapture (CMR). However, this method has not been evaluated on winter ranges or in snowy, winter conditions.

My first objective was to implement fecal DNA CMR to estimate abundance of mule deer in the Round Valley and Goodale winter survey areas in the …

An Exploration Of System Level Dimensions Of Nutrition In Relation To Health: Interprofessional Teams And Food Insecurity, Mckenna Christy Voorhees

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Many factors influence health; two such factors that warrant additional research include interdisciplinary healthcare teams and food insecurity. These factors may be particularly important among vulnerable populations such as individuals with special healthcare needs, lower income populations, and individuals with disabilities.

Interdisciplinary teamwork promotes improved, and more efficient patient care through the collaboration of healthcare providers in various professional disciplines. Registered Dietitian Nutritionists (RDNs) are experts in the science and application of nutrition, which plays an important role in various disease states. Despite the established need for RDNs on interdisciplinary teams, there is limited research in the interdisciplinary scholarship targeting …

Conservation Genetics Of A Declining Bumble Bee In Western North America; The Influence Of Geography, Dispersal Limitation, And Anthopogenic Activity, Ashley T. Rohde

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Conservation biology addresses the problem of species loss by identifying species in need of protection. Conservation biology has subfields to address different aspects of biodiversity loss, including genetics and sociology. I used genetic approaches to assess the conservation status of western bumble bees, a bumble bee species of conservation concern.

The western bumble bee is a bumble bee species that ranges from Alaska to New Mexico and as far east as Wyoming and Colorado. This species is disappearing in some places. It may soon be listed as endangered in the United States and is already listed as endangered in parts …

Development Of Late-Heading Orchardgrass Germplasm, Megan Marie Getz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dactylis glomerata L., orchardgrass, is commonly grown with perennial forages such as alfalfa (Medicago sativa L.). However, commercial orchardgrass cultivars currently grown in the Intermountain West generally flower earlier than alfalfa. This results in a reduction in grass nutritional value if harvested to maximize the alfalfa yield, because the two species mature at different rates. Thus, there is a need to better understand the genetic basis of flowering time in orchardgrass and develop late-flowering populations. The objectives of this research were to evaluate the ability to identify and use molecular markers to identify and select late-heading orchardgrass; and to …

Differential Transcriptome Analysis Reveals That Cache Valley Pm2.5 Triggers The Unfolded Protein Response In Human Lung Cells, Morgan Eggleston

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Worldwide, exposure to air pollution is a serious human health threat. Particulate matter (PM) air pollution is a mixture of suspended solid and/or liquid particles and particle size is determined by its aerodynamic diameter. Fine, or “respirable” particles, typically from vehicle emissions, manufacturing, power generation, agriculture, as well as secondary photochemical reactions, are classified as ≤2.5μm in diameter (PM_2.5). Upon inhalation, PM_2.5 particles can reach the lower, more sensitive regions of the lung, enter the bloodstream, and be distributed to other areas in the body. Large-scale epidemiology studies have shown that PM_2.5 air pollution is associated …

The Impacts Of Increased Precipitation Intensity On Dryland Ecosystems In The Western United States, Martin C. Holdrege

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As the atmosphere warms, precipitation events become larger, but less frequent. Such increases in precipitation intensity are expected regardless of changes in total annual precipitation. Despite strong evidence for increases in precipitation intensity, disagreement exists regarding how these changes will impact plants, and studies are lacking in many types of ecosystems. This dissertation addresses how increased precipitation intensity affects soil water availability, and how plants respond to any such changes. I address this question in the context of big sagebrush ecosystems and dryland winter wheat agriculture, which are both environments that can be sensitive to changes in water availability. Results …

Refining, Testing, And Applying Thermal Species Distribution Models To Enhance Ecological Assessments, Donald J. Benkendorf

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The temperature of streams and rivers is changing rapidly in response to a variety of human activities. This rapid change is concerning because the abundances and distributions of many aquatic species in streams and rivers are strongly associated with temperature. Linking observations of temperature effects on species distributions with observations of temperature effects on fitness is important for improving confidence that temperature (and not some other variable) is causing the distributions we observe. Furthermore, producing accurate models of temperature effects on species distributions may allow us to develop tools to diagnose whether or not thermal pollution has impaired aquatic life. …

Global Change Effects On Carbon Cycling In Terrestrial Ecosystems, Guopeng Liang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Since terrestrial ecosystems store approximately 3 times more carbon (C) than the atmosphere, they have a significant effect on the atmospheric CO₂ concentration. Although many studies have been conducted to determine global change effects on C cycling in terrestrial ecosystems, the underlying mechanisms remain uncertain. To address this knowledge gap, I utilized meta-analysis, laboratory experiments, and soil microbial community analysis.

In chapter 2, I conducted a meta-analysis to examine whether effects of long-term N addition on plant productivity can shift over time. I found that 44% of studies showed a marked trend (increase or decrease) in the strength of …

Forecasting Fine Fuels In The Intermountain West Rangelands, Mira Ensley-Field

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objective of this thesis project was to develop a fine fuels forecast to help fire managers anticipate spatial variation in fuel loads before the start of the fire season. In Chapter 1 we compile and analyze the methodologies of the historical record of fine fuel loads reported to the Great Basin Coordination Center. Based on our data analysis, we developed a series of recommendations for improving the methods used to sample fine fuels in the future as well as more broad ideas for how land managers can use emerging technologies to more effectively monitor fine fuels. In Chapter 2, …

Carnivoran Frugivory And Its Effect On Seed Dispersal, Plant Community Composition, Migration, And Biotic Carbon Storage, John P. Draper

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Seed dispersal by animals is important for the ecology of plants. It is particularly important to understand which animals are involved and how they move seeds differently from one another. Some seed dispersers are understudied despite ample evidence they consume fruits and seeds. This includes animals commonly referred to as carnivores in the order Carnivora. The overall goal of my dissertation was to describe the extent and quality of seed dispersal by Carnivorans, estimate important aspects of seed dispersal for a specific Carnivoran, the coyote, and estimate how differences between a coyote and songbirds affect where plants …