Physical Sciences and Mathematics Commons^™

Natural Resource Conflict And Socioenvironmental Resistance In Arctic States: Assessing Domestic Risks To Circumpolar Security, Jen Evans

Electronic Theses and Dissertations

How does climate change contribute to domestic natural resource conflict and socioenvironmental resistance in the Arctic? The literature assumes that developed Arctic nations possess sufficient state capacity to overcome risks of domestic conflict and unrest posed by regional development and environmental change. Arctic policy correspondingly focuses on natural resource competition, disputes, and conflict at the international level. The mechanisms and processes of domestic natural resource conflict and socioenvironmental resistance in the Arctic have thus been largely ignored in the literature, even though 27 cases of contention have occurred since the ‘shock’ sea-ice melt of 2007.

In this study, I draw …

Monarch Butterfly (Danaus Plexippus) Oviposition Preferences And A Survey Of Fungal Pathogens On Native Milkweeds (Asclepias) Of The Northern Great Plains, Grace Damiano

Electronic Theses and Dissertations

North American monarch butterfly (Danaus plexippus) populations are experiencing significant declines due to habitat loss caused by land use changes. Much of the American Midwest where milkweed, the only host plant of the monarch butterfly, was once much more abundant has been converted to a predominantly agricultural landscape. There are nineteen species of milkweed native to the northern Great Plains region occupied by South Dakota, North Dakota, and Minnesota. Some of these milkweed species may be preferable to monarch butterflies for different reasons, including morphological factors such as stem length, species-level chemical factors, and temporal factors. As monarch …

Impact Of Solar Radiation On Perchlorate Formation In The Atmosphere: Evidence From Ice Core Measurements, Bishnu Kunwar

Electronic Theses and Dissertations

Perchlorate, which derives from both anthropogenic and natural sources in the current environment, poses a substantial health hazard to humans as it competes with iodine uptake in the thyroid gland. Consequently, there has been considerable concern about minimizing human exposure to environmental perchlorate by restricting its release from man-made sources. However, the absence of a clear understanding regarding the respective contributions of man-made and natural sources has hindered widespread regulation efforts. A 300-year (1700–2007) Summit, Greenland ice core record from a previous study showed relatively stable perchlorate concentrations in Greenland snow prior to 1980, with some elevated perchlorate levels associated …

Species Distribution Modeling Of Aquilegia Brevistyla (Ranunculaceae): A Critically Imperiled Black Hills Disjunct Species, Eric Daniel Puetz

Electronic Theses and Dissertations

Unchecked human activity is contributing to rising levels of greenhouse gas emissions, changes in land use, altered disturbance/fire regimes, spread of invasive species, and loss of biological diversity and related breakdown of ecosystem services. Additionally, climatic shifts may lead to phenological mismatches between species and their environments if these changes outpace a species’ ability to adapt or migrate to a more suitable habitat. Isolated mountain populations are particularly threatened by unpredictable climatic conditions, as they may have limited migration corridors and often lower levels of genetic diversity to move or adapt, respectively. As these negative feedbacks compound on the landscape, …

The Hutton Project: Long-Term Agricultural Impacts On Soil Loss And Carbon Dynamics In Eastern South Dakota, Eli Halverson

Electronic Theses and Dissertations

Long-term and intensified agricultural land management has resulted in increased rates of soil erosion and has altered much of the carbon cycle at regional and global scales. Anthropogenic degradation of soil resources is a barrier to sustainable production, soil functioning, and ecosystem services. It is difficult to quantify the scope of pedogenic changes due to the lack of legacy data and short temporal scales. This study utilized decades to century-old soil information to quantify historical soil erosion losses and changes in soil carbon pools of eastern South Dakota soils. The results show that soils in the region have been significantly …

Rado Numbers For Two Systems Of Linear Equations, Anthony Glackin

Electronic Theses and Dissertations

For any positive integer n and any equation E of either the form x1+x2+· · ·+xn = x0 or x1 + x2 + n = x0, the two-color Rado number R2(E) is the least integer such that any 2-coloring of the natural numbers 1 through R2(E) will contain a monochromatic solution to E. Let Ek be a system of k equations of the aforementioned form, where Ei represents the ith equation in Ek and the set I = {1, 2, . . . , k} is the set of indices of these equations. This thesis shows that the two-color Rado …

The Effects Of Temperature, Flooding, And Goose Feces Addition On Greenhouse Gas Emissions And Ammonification In Four High-Latitude Soils From Western Alaska, Jenna M. Ross

Electronic Theses and Dissertations

The large carbon (C) stock of wetlands is vulnerable to climate change, especially in high latitudes that are warming at a disproportional rate. Likewise, low-elevation Arctic coastal areas will flood more frequently under climate change and sea-level rise, which may alter goose herbivory and fecal deposition patterns if geese move inland. While temperature, flooding, and feces impact soil C emissions, their interactive effects have been rarely studied. Here, I explore the impact of these interactions on CO2 and CH4 emissions and nitrogen (N) mineralization (ammonification) in soils collected from four plant communities in the Yukon-Kuskokwim (Y-K) Delta, a high latitude …

Effects Of Low-Cost, Low-Tech Tools For Riparian Restoration On Prairie Streams In Western South Dakota, James Andrew Joseph Bolyard

Electronic Theses and Dissertations

Despite making up less than two percent of the overall landscape in the arid and semi-arid western US, riparian areas are a crucial resource for agriculture, livestock, and wildlife. However, many have impaired function and reduced riparian cover. Low-Cost, Low-Tech Tools (LCLTT) are a subset of Process-Based Restoration (PBR) used for riparian restoration that were chosen for their cost-effectiveness and minimal technical requirements. LCLTT has been tested in mountainous areas of the western US but only recently implemented in the Northern Great Plains (NGP). Given their novelty as an approach toward restoration for the region, professional restoration and landowner communities …

Near-Real-Time Monitoring Of Crop Progress At Field Scales By Fusing Observations From Both Polar-Orbiting And Geostationary Satellites, Yu Shen

Electronic Theses and Dissertations

No abstract provided.

Plant Available Water Drives Semi-Arid Forage Quality And Quantity In A Common Garden Greenhouse Experiment, Parker J. Witt

Electronic Theses and Dissertations

Rangeland forage nutrition and biomass production are integral components of sustainable livestock grazing systems and are controlled by soil quality and precipitation. I examined the effects of precipitation on growth and nutrition of three forage species in four different soils that span the longitudinal moisture gradient in South Dakota. I grew little bluestem (Schizachyrum scoparium), western wheatgrass (Pascopyrum smithii), and smooth brome (Bromus inermis) in soils representing the eastern tallgrass/mid-grass prairie (Brookings, 700 mm avg. precipitation.), an eastern mid-grass prairie (Highmore, 550 mm avg. precipitation.), a western mid-grass prairie (Cottonwood, 450 mm avg. precipitation.), and a western mid-grass/short-grass prairie (Sturgis, …

Designing Ris-Assisted Uav 3d Trajectory Using Deep Reinforcement Learning, Linsong Li

Electronic Theses and Dissertations

Unmanned aerial vehicles (UAVs) are increasingly employed as temporary base stations or access points to facilitate data transfer between ground terminals (GTs). However, in urban environments, UAV-GT communication links often face challenges due to obstructions from buildings and other obstacles, resulting in reduced data transfer efficiency. Reconfigurable intelligent surfaces (RIS) provide a promising solution by reflecting signals to enhance communication quality between UAVs and GTs. This thesis addresses the critical challenge of responsive UAV trajectory optimization in RIS-assisted communication networks. A novel approach is proposed, integrating federated learning with reinforcement learning techniques, specifically Double Deep Q-Network (DDQN) and Deep Deterministic …

Contrastive Learning, With Application To Forensic Identification Of Source, Cole Ryan Patten

Electronic Theses and Dissertations

Forensic identification of source problems often fall under the category of verification problems, where recent advances in deep learning have been made by contrastive learning methods. Many forensic identification of source problems deal with a scarcity of data, an issue addressed by few-shot learning. In this work, we make specific what makes a neural network a contrastive network. We then consider the use of contrastive neural networks for few-shot learning classification problems and compare them to other statistical and deep learning methods. Our findings indicate similar performance between models trained by contrastive loss and models trained by cross-entropy loss. We …

Various Surfactant Soil Conditioner Effect On Plant Nutrient Concentration, Soil Nutrient Depletion, Soil Volumetric Water Content, Plant Biomass And Yield In Corn, Timothy Veldkamp

Electronic Theses and Dissertations

Soil conditioners help improve soil structure by increasing aeration, water infiltration and water holding capacity leading to nutrient availability and reduced irrigation needs. The goal of this study was to evaluate the impact of multiple soil conditioners (SC1, SC2, SC3, SC4, and SC5) on corn (Zea mays L.) and their ability to reduce irrigation by 30%. This was evaluated in the field in 2022 and 2023 by Aurora, SD using a Randomized Complete Block Design with six replications. Conditioners were applied as broadcast pre-emergence treatments with 70% irrigation. Control treatments of 70% and 100% irrigation, respectively were included. SC1 application …

Whole Genome Crispr-Cas9 Screens Identify Genes Contributing To Viral Entry And Phagocytosis, Md Saddam Hossain

Electronic Theses and Dissertations

CRISPR/Cas9 is a revolutionary technique for genome editing where Cas9 nucleases can be targeted to specific genomic sites by single-guide RNAs (sgRNAs) containing roughly 20-nucleotide sequences that are complementary to the target region. Double strand breaks created by Cas9 are repaired through non-homologous end-joining (NHEJ) in most cells, resulting in insertions and deletions leading to frame shift mutations in coding regions. Thus, the CRISPR-Cas9 system can be exploited for systematic evaluation of gene function relationships by whole genome screening. We also developed a CRISPR whole‐genome screen and counter‐screen strategy based on a pseudoviral platform that allowed identification of genes specific …

Analysis Of Toxic Chemical Agents And Therapeutics For Toxic Inhaled Agents’ Exposure, Khadija Bilkis

Electronic Theses and Dissertations

When inhaled, toxic inhalation agents (TIAs) such as cyanide (CN), ammonia and sulfur compounds (e.g. methanethiol (MeSH)) can be fatal. Many TIAs cause cellular hypoxia, cytotoxic anoxia, apnea, respiratory failure, neurodegenerative disorder, circulatory collapse, seizures, and potential death by blocking mitochondrial cytochrome c oxidase. All TIA’s have the potential to be employed as chemical warfare agents, terrorist weapons, or dangerous occupational gases. Although many TIAs are potential threats, there are minimal FDA-approved treatments for these substances useful in a mass-casualty situation. Recently, cobinamide (Cbi) has come to light as a potential antidote for MeSH poisoning. However, methods for analyzing MeSH …

Nitrogen Fertilizer Placement And Rate Impacts Sunflower Seed Yield, Oil And Protein Content, Rojina Kafle

Electronic Theses and Dissertations

South Dakota accounts for about 36% of the total US commercial sunflower production and nitrogen is a major input. Costs related to N fertilizer demand economically optimum N rates. This study investigated the impact of the N fertilizer placement method (broadcast vs band) and rate (0, 28, 56, 84, 112, 140 kg N ha-1) on leaf chlorophyll content, head diameter, seed yield, seed oil, and protein concentration of three sunflower hybrids in 2022 and 2023. The experiment was conducted at Brookings (eastern SD- conventional till, 66 cm rainfall) using an oil-type hybrid and at central SD sites (no-till, 57 cm …

Reimagining Hunting Through Women's Decision Space, H. Nash Jackson

Electronic Theses and Dissertations

Approximately 14.4 million people hunt in the United States, yet only 3.1 million (22%) of these hunters are women. To enhance women’s participation, many state natural resource agencies aim to reduce barriers and create pathways for women to hunt. Previously, researchers surveyed women to understand and describe barriers to their full participation in hunting. However, this methodology often just quantifies the different barriers without describing the interconnectedness and how the complexity of barriers can impact women’s participation in hunting. This thesis instead took an inductive research approach with the goal of better understanding women’s perspectives when faced with complex barriers. …

Improving Stream Connectivity In South Dakota, Colton Rainier Curtis

Electronic Theses and Dissertations

Stream connectivity is crucial for fish movement and genetic diversity in fragmented landscapes. Road-crossings often act as barriers, disrupting hydrology and isolating fish populations. The Southeast Aquatic Resources Partnership (SARP) has developed rapid road-crossing assessment protocols and tools to prioritize restoration projects. However, managers lack tools for planning, directing, and initiating roadcrossing assessments. Managers also require modeling approaches to effectively identify and monitor road-crossings across dynamic stream networks. Presented here is a case study offering a roadmap for effective implementation of collaborative road-crossing assessments and prioritization of remediation projects, alongside an exploration of predictive modeling approaches to identify problematic crossings …

The Effect Of Social Determinants Of Health On End-Stage Kidney Disease Mortality Across Diverse Adult Populations: Systematic Review And Meta-Analysis, Prince Agyapong

Electronic Theses and Dissertations

Background: This systematic review and meta-analysis aimed to examine the influence of social determinants of health (SDOH) on End-Stage Kidney Disease (ESKD) mortality among diverse racial populations. Given the high morbidity and mortality associated with ESKD, understanding the impact of various SDOH factors across different racial groups is crucial for improving patient outcomes.
Methods: A comprehensive literature search was conducted to identify studies reporting on the relationship between SDOH and ESKD mortality using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) format. Citations were collated in EndNote 21 and screened in Covidence by two independent reviewers, with inter-rater …

Portable X-Ray Fluorescence Spectrometry For Sensing Salinity And Sodicity In Glacial Northern Great Plains Soils With Machine Learning Models, Adam Devlin

Electronic Theses and Dissertations

Saline and sodic soils are an increasing concern across the Northern Great Plains (NGP) due to factors of climate change and land management that are drawing geologically derived salts to the land surface. Traditional laboratory assessments, such as electrical conductivity (EC) and sodium adsorption ratio (SAR), are time and resource consumptive. Portable X-ray fluorescence (PXRF) may be a viable proximal sensing alternative, as it is able to provide elemental data in minutes, in situ or ex situ, and can directly quantify salinity-associated elements like Ca, Mg, and S. PXRF paired with predictive models has proven useful for a range of …

Refining The Inverse Lipschitz Constant For Injective Relu Networks, Cole Rausch

Electronic Theses and Dissertations

In this thesis, we study the Inverse Lipschitz Constant (ILC) of injective ReLU layers. We study the tightness of the ILC lower bound established in Puthawala et al. Our approach has three components. First, we find that the conditions for injectivity on lines yield a weaker condition than the general condition given in Puthawala et al. Second, we perform numerical experiments to judge the tightness of the existing ILC lower bound and find that bound is overly conservative. Third, we identify the source of the potential slack in the proof of the existing ILC bound, and perform further numerical experiments …

Soil Responses To Eastern Redcedar (Juniperus Virginiana L.) Afforestation And Prescribed Fire In South-Central South Dakota, Robert Schaefer

Electronic Theses and Dissertations

Research was conducted in 2019 and 2020 on rangelands located in south-central South Dakota assessing a number of physical, chemical, and biological properties of mineral ustepts and ustents soils associated with eastern redcedar (ERC) (Juniperus virginiana) afforestation and prescribed fire. ERC afforestation appeared to be associated with significantly higher field-condition soil aggregate stability, cation exchange capacity (CEC), soil pH, and fungi:bacteria (F:B) as well as significantly lower soil moisture, nitrate-N, phosphorus, bacteria biomass, and Gram-positive:Gram-negative (GP:GN) bacteria compared to native grassland conditions, while other mineral soil properties appeared relatively unaffected. Compared to soil conditions under dense, living ERC canopies, prescribed …

Impacts Of Cover Crops And Diversified Crop Rotations On Soil Biochemical Properties, Hydrophysical Characteristics, And Water Dynamics In Long-Term No-Till Cropping Systems, Sainfort Vital

Electronic Theses and Dissertations

This research assessed the impacts of crop rotations and cover crops on the soil's biochemical and hydrophysical properties within long-term no-till systems. The research was conducted at the Southeast Research Farm, near Beresford, South Dakota. The crop rotations contain two levels: 4-year corn (Zea mays L.)-soybean (Glycine max L.)-oat (Avena sativa L.)-rye (Secale cereale L.) (CSOR) and 2-year corn-soybean (CS) rotations. The cover crop factors also had two levels within each rotation treatment: cover crops (CC) and no cover crops (NCC). All plots were managed under long-term no-till (NT), with soils mapped as Egan silty clay loam (fine-silty, mixed, superactive, …

Increasing Retention Of Women In Hunting And Fishing, Shelby Isensee

Electronic Theses and Dissertations

Despite national declines in hunting and fishing, women are making inroads in historically male-dominated sports. To further encourage women’s participation, states established programs to recruit, retain, and reactivate [R3] hunters and anglers. Women are participating in these programs and other recreational groups to access opportunities to learn skills and grow their networks. Yet, very little is known about what programs are offered for women, what aspects of programs are most effective to support women’s retention in these activities, and what women’s hunting and fishing groups are available across the landscape. To address these questions, I collected qualitative data from participant …

Respiratory Disease In Bighorn Sheep: A Varied Investigation Of Immunization, Transmission, And Detection, Katelin Frerichs

Electronic Theses and Dissertations

Respiratory disease has historically been recognized as a limiting factor to wild bighorn sheep (Ovis canadensis) herds throughout North America with epizootics resulting in large-scale die offs and reductions in recruitment. The primary etiologic agent associated with pneumonia outbreaks in bighorn sheep is Mycoplasma ovipneumoniae. This bacterial pathogen is frequently carried asymptomatically by domestic sheep (Ovis aries) and goats (Capra hircus); however, when these domestic hosts come in contact with and spread this pathogen to bighorns, the disease can cause epizootics and large-scale mortality. Domestic sheep strains are more commonly detected in bighorn sheep than domestic goat strains, and previous …

Comparative Lineament And Geomorphic Analysis Of Chaotic Terrains And Noctis Labyrinthus, Mars, Sarah A. Walton

Electronic Theses and Dissertations

Noctis Labyrinthus (NL) is an extensional trough network connecting the Tharsis rise and Valles Marineris on Mars. Chaotic terrains are a group of polygonally-fractured surface features commonly associated with subsidence due to rapid fluid loss within the subsurface. Polygonal surface patterns are seen at both sites, where geometric topographic highs are bounded by low troughs. Lineaments, topography, and geomorphology of NL and chaotic terrains were analyzed to determine tectonics and fluid influence in the formation and evolution of both sites. NL shows preferential fracture patterns associated with regional extension. Lineaments within chaotic terrains do not show cumulative preferential trends but …

Interactive Effects Of Sublethal Concentrations Of Fracking Biocides And Abandoned Mine Drainage On Amphipod Behavior, Kelly Lenhart

Electronic Theses and Dissertations

This thesis examined the sublethal effects of three pollutants, namely glutaraldehyde, 4,4-dimethyloxazolidine (DMO), and abandoned mine drainage (AMD), on amphipods. The primary objective was to investigate their combined effects on amphipods. The three pollutants, despite having the potential to combine in the environment, have not been studied to determine their potential for detrimental interactive effects which could result in unexpected environmental damage.

The research employed a series of experimental setups involving controlled exposure of amphipods to varying, putatively sublethal, concentrations of the chemicals of interest. Subsequently, effects were assessed via both behavioral and feeding assessments. To facilitate this analysis, novel …

Quantifying Current Soil Brine Contamination Within The Smackover Oil Field In Arkansas Using Multispectral Digital Imagery, Victoria Williams

Electronic Theses and Dissertations

A remote sensing study was performed to quantify current soil brine contamination across the historic Smackover Oil Field in south-central Arkansas, United States. The oil field was established in 1922 and was not subject to the future waste regulations created by the Arkansas Oil and Gas Commission. Brine is a waste product of oil manufacturing which contains water with high salt levels. The storage and transport of brine in the oil field created landscape scarring across the study area.

Landsat 9 multispectral digital imagery was utilized to create supervised classification maps based on earthen pits and creek scarring across the …

Bayesian Strategies For Propensity Score Estimation In Causal Inference., Uthpala I. Wanigasekara

Electronic Theses and Dissertations

Causal inference is a method used in various fields to draw causal conclusions based on data. It involves using assumptions, study designs, and estimation strategies to minimize the impact of confounding variables. Propensity scores are used to estimate outcome effects, through matching methods, stratification, weighting methods, and the Covariate Balancing Propensity Score method. However, they can be sensitive to estimation techniques and can lead to unstable findings. Researchers have proposed integrating weighing with regression adjustment in parametric models to improve causal inference validity. The first project focuses on Bayesian joint and two-stage methods for propensity score analysis. Propensity score modeling …

Synthesis Of Bacterial Glycerophospholipids For Biomembrane Model Studies: A Means To Advanced Biofuels, Felix Adulley

Electronic Theses and Dissertations

To reduce reliance on fossil fuels, sustainable biofuels are being pursued, especially advanced biofuels like 1-butanol that have higher energy content and greater compatibility with existing infrastructure than ethanol. A persistent challenge is the yield-limiting toxicity of biofuels and process solvents, such as tetrahydrofuran, to the microbes that ferment biomass into biofuel. The cell membrane is a focal point of toxicity, and understanding how it interacts with fuels and solvents is key to improving yield. Phospholipid bilayers are the core of biomembranes, and model biomembranes of defined composition provide the ideal platform for biophysical studies. To this end, glycerophospholipids characteristic …