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Full-Text Articles in Physical Sciences and Mathematics

Assaying Bacillus Amyloliquefaciens Isolates 1ba And 1d3 For Biosurfactant Production And Utilization Of Petroleum Hydrocarbons And Phenolic Acids, Pavan Kulkarni Jan 2021

Assaying Bacillus Amyloliquefaciens Isolates 1ba And 1d3 For Biosurfactant Production And Utilization Of Petroleum Hydrocarbons And Phenolic Acids, Pavan Kulkarni

Electronic Theses and Dissertations

Several Bacillus amyloliquefaciens isolates obtained from wheat residue have been studied as biological agents to control wheat diseases. Notable traits of isolates 1BA and 1D3 include growth with high salt (10% NaCl), at temperatures up to 50°C and over a wide pH range. BIOLOG Gen III plates were used to study and further characterize Bacillus amyloliquefaciens 1BA and 1D3. Both isolates showed tolerance to high salt concentration supporting previous studies. They also grew in the presence of lithium chloride, potassium tellurite, and sodium bromate. Both isolates grew at pH 5, with almost identical carbon source utilization fingerprints. However, D-serine, quinic …


A Speciation Modeling Study Of Heavy Metal Adsorption To Plastic In Municipal Wastewater Treatment Plant Units, Kaitlyn Hague Jan 2021

A Speciation Modeling Study Of Heavy Metal Adsorption To Plastic In Municipal Wastewater Treatment Plant Units, Kaitlyn Hague

Electronic Theses and Dissertations

Microplastics are an emerging concern due to their harmful effect to organisms and their ability to facilitate transport of contaminants including heavy metals. Microplastics can enter the environment through wastewater treatment plants, landfill leachate, and littering. Once in the environment microplastics can be distributed throughout rivers, the ocean, and lakes. In order to understand the adsorption of heavy metals to microplastics a geochemical modeling study was completed using Visual Minteq. Lab tests were completed to better understand what constituents are available in wastewater at four different locations: influent, clarifiers, digesters, and effluent. These constituents were then used to observe how …


Enhanced Electrochemical And Light-Driven Co2 Reduction By Incoporating Pendant Functionality In The Second-Coordination Sphere Of Molecular Catalysts, Sayontani Sinha Roy Jan 2021

Enhanced Electrochemical And Light-Driven Co2 Reduction By Incoporating Pendant Functionality In The Second-Coordination Sphere Of Molecular Catalysts, Sayontani Sinha Roy

Electronic Theses and Dissertations

With the increase in global population and rapid industrialization, a gigantic amount of greenhouse gases is being released into the atmosphere each year. The catastrophic effect of these accumulated greenhouse gases is driving global climate change and adversely impacting our ecosystem. Popularizing the traditional renewable energy sources (such as solar and wind energy) can mitigate the problem by cutting down anthropogenic CO2 emissions, which is the major contributor to this global problem. However, the intermittent nature of these energy sources is problematic to reliably power society throughout the year. Therefore, converting CO2 to various value-added chemicals with the aid of …


Constructing And Validating Feature Models Using Relational, Document, And Graph Databases, Hazim Shatnawi Jan 2021

Constructing And Validating Feature Models Using Relational, Document, And Graph Databases, Hazim Shatnawi

Electronic Theses and Dissertations

Building a software product line (SPL) is a systematic strategy for reusing software within a family of related systems from some application domain. To define an SPL, a domain analyst must identify the common and variable aspects of a family of systems and capture them for later use in construction of specific products. To do so, Feature-Oriented Domain Analysis (FODA) introduced the feature model as an abstraction to represent the common and variable aspects, using a feature diagram to depict the model visually. However, this abstraction is often difficult for developers to use because most tools rely on specialized theories, …


A Valence-Bond Operator Algebra For Quantum Spin Models And Its Applications, Huu Tran Do Jan 2021

A Valence-Bond Operator Algebra For Quantum Spin Models And Its Applications, Huu Tran Do

Electronic Theses and Dissertations

The Heisenberg Hamiltonian is the prototype model for quantum magnetism. The Hamilto- nian includes exchange couplings between vector spins, which are the intrinsic magnetic moments of localized electrons. The classical energy between any pair of interacting spins can be minimized by aligning them parallel (ferromagnetic case) or antiparallel (antiferromagnetic), depending on the sign of the coupling. But quantum fluctuations play a key role, and a full quantum mechanical treatment of the many-body system is generally required. Finding the exact ground-state energy and wave function of isotropic antiferromagnetic (AFM) systems for an arbitrary spin-S and lattice morphology is still a challenging …


Dynamics For Discretized Gravity In The Causal Set Approach, Benjamin Pilgrim Jan 2021

Dynamics For Discretized Gravity In The Causal Set Approach, Benjamin Pilgrim

Electronic Theses and Dissertations

Causal set theory is an approach to quantum gravity which replaces the continuous spacetime manifold with a discrete set of points and a partial order. In this work, I will focus on causal sets embeddable in two-dimensional manifolds, and define an action based on chains which in the continuum limit replicates the Einstein-Hilbert action; furthermore, I will propose a variational principle based on this action and numerically show it can distinguish nonflat manifoldlike causal sets from the most common type of nonmanifoldlike causal sets. I will then supplement this action with a boundary term similar to the Gibbons-Hawking-York boundary term …


Topics On Applications Of Optimization Theories On Statistical Methodologies, Duc Anh Anh Doan Jan 2021

Topics On Applications Of Optimization Theories On Statistical Methodologies, Duc Anh Anh Doan

Electronic Theses and Dissertations

In this dissertation, We show the results of our researches in statistical sampling, functional optimization, and methodology for partially observed Markov process (POMP) models. In statistical sampling, we introduce a p-generalized smoothing method that enables the Langevin-Monte Carlo method to generate a sample from a log concave distribution weakly smoothing potential function. For our optimization research, we introduce an accelerated inexact gradient (AIG) method. Combining the strengths while mitigating the weakness of its parent methods: gradient descent and Nesterov's accelerated gradient, AIG converges with excellent rates for both convex and non-convex optimization problems for smooth objective functions. Furthermore, we also …


Evaluating Canola Genotypes For Growth And Yield Under Different Environmental Conditions In South Dakota, Unius Arinaitwe Jan 2021

Evaluating Canola Genotypes For Growth And Yield Under Different Environmental Conditions In South Dakota, Unius Arinaitwe

Electronic Theses and Dissertations

Canola (Brassica napus L) and carinata (Brassica carinata A. Braun) are potential oilseed crops for diversifying cropping systems and expanding into marginal lands impacted by saline and sodic soils in South Dakota (SD). However, genotypes that are high yielding, with high agronomic adaptability and stability over diverse environments, and salt tolerant have not been selected. One field experiment was conducted at two environments (Brookings - eastern SD and Pierre - western SD) from 2019 to 2020 to evaluate genotypes for growth and yield stability. Three greenhouse experiments were conducted to evaluate genotypes for salt tolerance in …


An Integrative Analysis On The Role Of Notch1 And Notch3 In Musculoskeletal Disease, Haydee Magdalena Torres Jan 2021

An Integrative Analysis On The Role Of Notch1 And Notch3 In Musculoskeletal Disease, Haydee Magdalena Torres

Electronic Theses and Dissertations

Notch signaling is an evolutionarily conserved signaling pathway involved in cell fate decisions and cell renewal of multiple systems, including skeletal and muscle homeostasis. As the multifunctional nuclear complex of Notch1 is essential for its pathological function, identifying these interacting partners represents a potentially broad range of druggable vulnerabilities. We have completed a BioID proteomics study and found a large set of nuclear proteins associated with NOTCH1, including transcriptional regulators and epigenetic modulators, of which Histone Deacetylase 1 (HDAC1) is a promising interacting partner of Notch1. Our Cytoscape analysis predicted HDAC1 to be a top critical node in an activated …


Development And Properties Of The Roc-Abc Bayes Factor For The Quantification Of The Weight Of Forensic Evidence, Jessie Hendricks Jan 2021

Development And Properties Of The Roc-Abc Bayes Factor For The Quantification Of The Weight Of Forensic Evidence, Jessie Hendricks

Electronic Theses and Dissertations

Many scholars have proposed the use of a Bayes factor to quantify the weight of forensic evidence. However, due to the complex and high-dimensional nature of pattern evidence, likelihood functions are intractable and thus, Bayes factors cannot be assigned using traditional methods. Approximate Bayesian Computation (ABC) model selection algorithms provide likelihood-free methods to assign Bayes factors. ABC Bayes factors leverage the use of the scoring functions commonly used in recent years in forensic statistics in a rigorous statistical manner. However, traditional methods for assigning ABC Bayes factors are subject of several criticisms. In this dissertation, one of the main criticisms …


Search For Cpt And Lorentz Invariance Violation In The Muon G-2 Experiment At Fermilab, Meghna Bhattacharya Jan 2021

Search For Cpt And Lorentz Invariance Violation In The Muon G-2 Experiment At Fermilab, Meghna Bhattacharya

Electronic Theses and Dissertations

The Muon g-2 experiment at Fermilab (E989) aims to measure the anomalous magnetic moment of the muon, $a_{\mu}= (g-2)/2$, to a groundbreaking precision of $140$ ppb, obtaining a near four-fold increase in precision over the previous experiment, E821, at the Brookhaven National Laboratory (BNL). The value of $a_{\mu}$ from BNL currently differs from the Standard Model prediction by $\sim 3.7$ standard deviations, suggesting the potential for new physics and therefore, motivating a new experiment.Because the theory predicts this number with high precision, testing the g-factor through experiment provides a stringent test of the SM and can suggest physics beyond the …


A Hydrologic Study Of Climate Variability In Arid Region, Abdullah Alzaydani Jan 2021

A Hydrologic Study Of Climate Variability In Arid Region, Abdullah Alzaydani

Electronic Theses and Dissertations

Climate variability is an important subject to study. It is the change of climate over a long time, which could have a positive or negative impact on humans, soil, and wildlife. Many environments, such as arid environment could be affected by climate variability. The research goal is studying and examining climate variability in arid environment. The research includes three different studies. The first study includes reviewing and understanding of climate variability over extended time through existing studies in arid environments. In addition, this study includes knowledge about climate negative or positive impact on the environment. This study will be reviewing …


Detailing The Connection Between A Family Of Polar Graphs And Tremain Equiangular Tight Frames, Nicholas Brown Jan 2021

Detailing The Connection Between A Family Of Polar Graphs And Tremain Equiangular Tight Frames, Nicholas Brown

Electronic Theses and Dissertations

The relationship between strongly regular graphs and equiangular tight frames has been known for several years, and this relationship has been used to construct many of the most recent examples of new strongly regular graphs. In this paper, we present an explicit construction of a family of equiangular tight frames using the geometry of a quadratic space over the field of four elements. We observe that these frames give rise to a strongly regular graph on a subset of points of a quadratic space over the field with 4 elements. We then demonstrate an isomorphism between this graph and a …


Effects Of Harvest Regulations And Post-Release Hooking Mortality On Walleye Populations In South Dakota, Cade Lyon Jan 2021

Effects Of Harvest Regulations And Post-Release Hooking Mortality On Walleye Populations In South Dakota, Cade Lyon

Electronic Theses and Dissertations

Harvest regulations are commonly implemented to manipulate fisheries stocks. By regulating the size and number of fish that are harvested by anglers, managers are able to meet the goals and needs of regions. However, these management actions come with the potential for negative consequences. Overexploitation due to less restrictive harvest regulations can cause collapses in fisheries populations. In addition, indirect consequences such as hooking mortality brought on by length-based regulations can also be detrimental to populations. In this study, I investigated the effects of various harvest regulations on Walleye populations in three western South Dakota irrigation reservoirs: Angostura, Belle Fourche, …


Stratigraphy And Geochemistry Of Paleocene-Aged Bauxites From North Mississippi, Timothy Brendan Clark Jan 2021

Stratigraphy And Geochemistry Of Paleocene-Aged Bauxites From North Mississippi, Timothy Brendan Clark

Electronic Theses and Dissertations

Bauxite is a heavily-mined aluminum ore that forms through the relative depletion of silica to aluminum. In North Mississippi, bauxite occurring within the Upper Midway and Lower Wilcox groups has been the subject of study for over a century. Despite the abundance and duration of research, controversy surrounds the subjects of bauxite genesis and economic value. The last detailed study of North Mississippi bauxite was in the 1980’s, so the goal of this project is to apply newly available technologies and modern hypotheses on bauxite formation to refine and obtain new data. Fieldwork observations yielded pisoliths, horizonation, and possible rhizoliths, …


Polyester-Pamam “Janus-Type” Linear-Dendritic Blockopolymers (Ldbcs) As Next Generation Biomaterials, Indika Chandrasiri Jan 2021

Polyester-Pamam “Janus-Type” Linear-Dendritic Blockopolymers (Ldbcs) As Next Generation Biomaterials, Indika Chandrasiri

Electronic Theses and Dissertations

Nanomedicine is defined as the application of knowledge and tools of nanotechnology for disease treatment, diagnosis, monitoring, delivery, and sensing. Rapid advances in polymer chemistry and nanotechnology have led to an extensive development of polymeric-based therapeutic systems for nanomedical applications. Compared to traditional molecular-based therapies, polymers facilitate a higher level of versatility and functionality, such as simultaneous imaging and delivery. In particular, amphiphilic diblock copolymers and their self-assemblies have shown apparent success in nanomedicine owing to their ability to provide narrow molar mass distributions and highly ordered nanoscale multimolecular aggregates, including micelles and vesicles. However, engineering these polymeric materials to …


Advancements Toward Sustainable Solar Fuel Production Utilizing Reductive Homogeneous Electro- And Photocatalysis, Hunter Pratt Shirley Jan 2021

Advancements Toward Sustainable Solar Fuel Production Utilizing Reductive Homogeneous Electro- And Photocatalysis, Hunter Pratt Shirley

Electronic Theses and Dissertations

Molecular CO2 and H+ reductive catalysts, whether they be electro- or photocatalytic, have been shown to be possible routes of harnessing solar energy in a clean, renewable manner. There are few electrocatalysts operating at reasonable overpotentials to prove useful in artificial photosynthetic systems, and there are a number of environmental factors within these systems that have yet to be evaluated. Photo-driven catalysis is rare, difficult to control, and rarely provides high-value CO2 reduction products. I report herein an exceptionally low overpotential H+ reduction catalyst, a method of modulating electrocatalysts in-situ to improve performance, a first-of-its-kind mononuclear proton reduction photocatalyst, a …


Application Of Passive Air Samplers For Atmospheric Research, And Determination Of Metals In Tree Rings And Marine Sapropel By Icp-Ms, Byunggwon Jeon Jan 2021

Application Of Passive Air Samplers For Atmospheric Research, And Determination Of Metals In Tree Rings And Marine Sapropel By Icp-Ms, Byunggwon Jeon

Electronic Theses and Dissertations

This research focuses on studies of atmospheric mercury (Hg) using passive air samplers (PAS) and studies of trace elements in tree cores and sediment using inductively coupled plasma mass spectrometry (ICP-MS). Mercury is a toxic element that is dispersed globally through the atmosphere. Accurately measuring airborne Hg concentrations aids understanding of the pollutant’s sources, distribution, cycling, and trends. Mercury PAS are designed to capture gaseous elemental mercury (GEM) at a known rate. Compared to active air sampling the low-cost of PAS allows for greater spatial coverage. We used a commercially available Hg PAS (MerPAS®) and observed differences in GEM between …


Advanced Analytical Techniques For The Analysis Of Therapeutics Of Toxic Inhalation Agents And Pharmacokinetic Investigation, Subrata Bhadra Jan 2021

Advanced Analytical Techniques For The Analysis Of Therapeutics Of Toxic Inhalation Agents And Pharmacokinetic Investigation, Subrata Bhadra

Electronic Theses and Dissertations

Toxic inhalation agents (TIAs), (i.e., cyanide (CN) and reduced sulfur compounds (RSCs)), including hydrogen sulfide (H2S) and methanethiol (MT)) are extremely poisonous upon exposure. Many TIAs act by inhibiting mitochondrial cytochrome c oxidase, resulting in cellular hypoxia, cytotoxic anoxia, apnea, respiratory failure, cardiovascular collapse, seizure and potentially death. CN is generated in structural fires and cigarette smoke as well as in mining, electroplating and polymer processing, whereas H2S and MT are found in petroleum, oil and natural gas, waste treatment facilities and decaying organic matter. All are common occupational gas exposure hazards in chemical industries and for first responders, including …


Evaluating And Predicting The Risk Of Algal Blooms In A Freshwater Lake Through A 4-Dimensional Approach: A Case Study On Lake Mitchell, Sumit Kumar Ghosh Jan 2021

Evaluating And Predicting The Risk Of Algal Blooms In A Freshwater Lake Through A 4-Dimensional Approach: A Case Study On Lake Mitchell, Sumit Kumar Ghosh

Electronic Theses and Dissertations

Excessive algal growth in freshwater lakes can negatively impact ecosystems, recreation, and human health. Though algae are a natural part of freshwater ecosystems, elevated nutrient loading from anthropogenic and natural sources can lead to algal blooms. Both algae and blue-green algae (BGA) are responsible for algal blooms; however, BGA (cyanobacteria) is more dangerous. The first objective of this research was to prepare a conceptual model to understand how various environmental variables affect algae. This conceptual model was used to choose the environmental variables that help increase or decrease algae in the water environment. The second objective was to develop empirical …


Methods For High-Dimensional Spatial Data: Dimension Reduction And Covariance Approximation, Paul May Jan 2021

Methods For High-Dimensional Spatial Data: Dimension Reduction And Covariance Approximation, Paul May

Electronic Theses and Dissertations

In spatial statistics, because quantities are correlated based on their relative positions in space, data is modeled as a single realization of a multivariate stochastic process. Spatial data can be high-dimensional either through a large number of observed variables per location, or through a large number of observed locations. The two are often handled differently, with the former addressed through dimension reduction and the latter addressed through appropriate modeling of the spatial correlation between locations. The main body of this dissertation is a three-part work. Parts 2 and 3 pertain to the "many variables" problem, proposing novel methods of dimension …


Zn Orbifolds Of Vertex Operator Algebras, Daniel Graybill Jan 2021

Zn Orbifolds Of Vertex Operator Algebras, Daniel Graybill

Electronic Theses and Dissertations

Given a vertex algebra V and a group of automorphisms of V, the invariant subalgebra VG is called an orbifold of V. This construction appeared first in physics and was also fundamental to the construction of the Moonshine module in the work of Borcherds. It is expected that nice properties of V such as C2-cofiniteness and rationality will be inherited by VG if G is a finite group. It is also expected that under reasonable hypotheses, if V is strongly finitely generated and G is reductive, VG will also be strongly finitely generated. This is an analogue …


Use Of Research Tradition And Design In Program Evaluation: An Explanatory Mixed Methods Study Of Practitioners’ Methodological Choices, Margaret Schultz Patel Jan 2021

Use Of Research Tradition And Design In Program Evaluation: An Explanatory Mixed Methods Study Of Practitioners’ Methodological Choices, Margaret Schultz Patel

Electronic Theses and Dissertations

The goal of this explanatory sequential mixed method study was to assess whether there were observable trends, associations, or group differences in evaluation methodology by settings and content area in published evaluations from the past ten years (quantitative), to illuminate how evaluation practitioners selected these methodologies (qualitative), and assess how emergent findings from each phase fit together or helped contextualize each other. In this study, methodology was operationalized as research tradition and method was operationalized as research design. For phase one (quantitative), a systematized ten-year review of five peer-reviewed evaluation journals was conducted and coded by journal, research tradition, research …


Exponential Random Graphs And A Generalization Of Parking Functions, Ryan Demuse Jan 2021

Exponential Random Graphs And A Generalization Of Parking Functions, Ryan Demuse

Electronic Theses and Dissertations

Random graphs are a powerful tool in the analysis of modern networks. Exponential random graph models provide a framework that allows one to encode desirable subgraph features directly into the probability measure. Using the theory of graph limits pioneered by Borgs et. al. as a foundation, we build upon the work of Chatterjee & Diaconis and Radin & Yin. We add complexity to the previously studied models by considering exponential random graph models with edge-weights coming from a generic distribution satisfying mild assumptions. In particular, we show that a large family of two-parameter, edge-weighted exponential random graphs display a phase …


Accurate Quantitation Of Hexavalent Chromium For Reference Standard Certification And Quality Control Testing Using Speciated Isotope Dilution Mass Spectrometry, James E. Henderson Dec 2020

Accurate Quantitation Of Hexavalent Chromium For Reference Standard Certification And Quality Control Testing Using Speciated Isotope Dilution Mass Spectrometry, James E. Henderson

Electronic Theses and Dissertations

The ability to perform accurate, repeatable, and defensible elemental and molecular speciated analysis is immensely significant for measurements that support human health, environmental science, and industry. This is especially true since trivalent chromium [Cr(III)] is necessary for proper nutrition, while hexavalent chromium [Cr(VI)] is extremely toxic, genotoxic, and carcinogenic. The main challenges associated with speciated analysis are related to reactive species that are continuously transformed or converted to other species during sample processing. Accurate determination of Cr(III) and Cr(VI) species require a method that is capable of monitoring and correcting for interconversion, bias, and instrumental error. Traditional quantitative methods, such …


Functionalized Materials From Atom Transfer Radical Processes, Sean Fischer Dec 2020

Functionalized Materials From Atom Transfer Radical Processes, Sean Fischer

Electronic Theses and Dissertations

This work is focused on the synthesis, characterization, and application of functionalized materials prepared from atom transfer radical processes. Atom transfer radical processes encompass both atom transfer radical addition (ATRA) and polymerization (ATRP) reactions, both of which are catalyzed by ppm amounts of copper complexes. The synthetic efforts of ATRA include increasing adduct selectivity through optimization of reaction conditions to generate small molecules in high to moderate yields. ATRA provides retention of the halogen moiety, which is an attractive functional group that can be further modified with other transformations. Specifically, the copper-catalyzed azide-alkyne [3+2] cycloaddition (CuAAC) allows for the realization …


Atom Transfer Radical Processes: From Catalyst Design To Polymer Synthesis, Characterization, And Application, Michael Novak Dec 2020

Atom Transfer Radical Processes: From Catalyst Design To Polymer Synthesis, Characterization, And Application, Michael Novak

Electronic Theses and Dissertations

Due to the toxicity of heavy metals and their prevalence in the environment there exists a need to develop highly active transition metal catalysts ultimately reducing the amount needed for chemical transformations. Additionally, there is interest in the scientific community for creating new materials that can remove these pollutants from industrial wastewater prior to its release into the environment. The work presented here focuses on the reduction and removal of heavy metals from industrial hazardous waste by designing novel highly active catalysts and developing polymeric adsorbents.

Highly active catalyst complexes consisting of novel hybrid ligands, 2-(dimethylamino)ethyl-bis-[2-(pyridylmethyl)amine] (M1-T2), and bis[2-(dimethylamino)ethyl]-2-(pyridylmethyl)amine (M2-T1), …


Fluoride Removal With Augmented Bentonite In Drinking Water And Community Perceptions In Arusha, Tanzania, Kara Okular Dec 2020

Fluoride Removal With Augmented Bentonite In Drinking Water And Community Perceptions In Arusha, Tanzania, Kara Okular

Electronic Theses and Dissertations

High fluoride concentrations in drinking water affect millions of people around the world. The World Health Organization recommended a fluoride concentration in drinking water of ≤ 1.5 mg/L; fluoride above this concentration can cause long-term dental and skeletal fluorosis. Fluoride imparts no taste to water; therefore, people do not realize that they are ingesting high fluoridated water. Researchers sought to develop a material to remove fluoride from drinking water through sorption. Aluminum was used to form a double ionic layer on the bentonite clay surface. Once mixed in contaminated water, a coagulant, ferric sulfate, was used to separate the bentonite …


Control Of Corrosion On Ss316l Using Surface Initiated Polymers, Alexander Rupprecht Dec 2020

Control Of Corrosion On Ss316l Using Surface Initiated Polymers, Alexander Rupprecht

Electronic Theses and Dissertations

Pitting corrosion is arguably one of the most destructive and dangerous forms of corrosion, resulting in damage to structures, the environment, and public health. In addition, damage caused to structures such as bridges, pipelines, and boats, corrosion also has a profound effect on the biomedical community. Implanted metallic devices (i.e., vascular stents and artificial joints) are prone to pitting corrosion caused by aggressive ions present in extracellular fluid. To provide a corrosion-resistant surface on SS316L, films of poly(styrene), poly(methyl acrylate), and poly(methyl methacrylate) were formed using surface-initiated atom transfer radical polymerization (SI-ATRP). The resulting hydrophobic polymer films had a fractional …


Species Distribution Modeling For Arid Adapted Habitat Specialists In Zion National Park, Sam Driver, Chris M. Schalk, Daniel Unger, David Kulhavy Dec 2020

Species Distribution Modeling For Arid Adapted Habitat Specialists In Zion National Park, Sam Driver, Chris M. Schalk, Daniel Unger, David Kulhavy

Electronic Theses and Dissertations

The Arizona toad (Anaxyrus microscaphus) and Jones’ waxy dogbane (Cycladenia humilis var. jonesii) are habitat specialists with historical ranges in the desert southwest and specifically, Zion National Park (ZION). The machine learning method, MaxEnt, constructed species distribution models (SDMs) in ZION for the two study species at 30 m and 900 m spatial resolutions using climate, topographic, and remotely sensed data. Additionally, 900 m forecasting models were constructed to observe the shifts in suitable habitat for the years 2050 and 2070, based off two representative concentration pathway scenarios. Results indicate promising predictive power for both high …