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Full-Text Articles in Physical Sciences and Mathematics

Evaluating Spatial-Temporal Patterns In Us Tornado Occurrence With Space Time Cube Analysis And Linear Kernel Density Estimation: 1950-2019, Darrell L. Wiser Aug 2022

Evaluating Spatial-Temporal Patterns In Us Tornado Occurrence With Space Time Cube Analysis And Linear Kernel Density Estimation: 1950-2019, Darrell L. Wiser

Electronic Theses and Dissertations

This research estimated the spatial-temporal patterns of tornadoes in the continental United States from 1950-2019 using the National Weather Service Storm Prediction Center’s Severe Weather GIS (SVRGIS) database. This study employed Space-Time Cube Analysis and Linear Kernel Density (Kernel Density Linear Process, (KDLP)) rather than the standard Kernel Density Estimation (KDE) approach; to evaluate whether tornado hotspot locations and intensities shift over time.

The first phase of the study utilized KDLP to map changes in tornado hotspots and qualitatively assess decadal shifts in hotspot locations and intensities by occurrence and magnitude between decades using ArcGIS Pro and CrimeStat. Next an …


Spatial Analyses Of Gray Fossil Site Vertebrate Remains: Implications For Depositional Setting And Site Formation Processes, David Carney Aug 2021

Spatial Analyses Of Gray Fossil Site Vertebrate Remains: Implications For Depositional Setting And Site Formation Processes, David Carney

Electronic Theses and Dissertations

This project uses exploratory 3D geospatial analyses to assess the taphonomy of the Gray Fossil Site (GFS). During the Pliocene, the GFS was a forested, inundated sinkhole that accumulated biological materials between 4.9-4.5 mya. This deposit contains fossils exhibiting different preservation modes: from low energy lacustrine settings to high energy colluvial deposits. All macro-paleontological materials have been mapped in situ using survey-grade instrumentation. Vertebrate skeletal material from the site is well-preserved, but the degree of skeletal articulation varies spatially within the deposit. This analysis uses geographic information systems (GIS) to analyze the distribution of mapped specimens at different spatial scales. …


Land Suitability Analysis For Windfarm Development In Texas, Robert Laszlo Milecz Aug 2020

Land Suitability Analysis For Windfarm Development In Texas, Robert Laszlo Milecz

Electronic Theses and Dissertations

Due to the negative impact on the environment of conventional electric power generation methods, especially coal and oil-fired generating plants, wind power as an alternative for sustainable energy has received more attention in recent years. The purpose of this project was to apply Geographic Information System (GIS), integrated with Multi Criteria Decision Making (MCDM), for identifying suitable areas for wind turbine applications in Texas. Factors taken into consideration included socioeconomic criteria such as distance to highways, proximity to airports and urban areas, localized environmental criteria such as terrain slope and distance to rivers, affected waterbodies, and wildlife management areas. Also …


Utilizing The Public On Public Lands: The Application Of Community Science To Monitor And Model Erosion In National Forests, Jacob L. Hansen Aug 2020

Utilizing The Public On Public Lands: The Application Of Community Science To Monitor And Model Erosion In National Forests, Jacob L. Hansen

Electronic Theses and Dissertations

Unpaved forest roads are adversely affecting coldwater streams through excessive erosion and the subsequent sedimentation of adjacent waterways. To help identify areas of concern, Trout Unlimited (TU) in the Southern Appalachian region developed a Community Science initiative to gather data on sediment sources and stream-road crossings. Volunteers were recruited and trained to monitor road and trail conditions and collect and submit data using a Survey123 application on their cell phones. Analysis of the contributed data reveals statistical connections between drainage type and both erosion level and stream sedimentation. The contributed data were also included as a calibration for the lite …


Archaeological, Geophysical, And Geospatial Analysis At David Crockett Birthplace State Park, In Upper East Tennessee, Reagan Cornett May 2020

Archaeological, Geophysical, And Geospatial Analysis At David Crockett Birthplace State Park, In Upper East Tennessee, Reagan Cornett

Electronic Theses and Dissertations

A geophysical survey was conducted at David Crockett Birthplace State Park (40GN205, 40GN12) using ground-penetrating radar (GPR) and magnetometry. The data indicated multiple levels of occupation that were investigated by Phase II and Phase III archaeological excavations. New cultural components were discovered, including the remnants of a Protohistoric Native American structure containing European glass trade beads and Middle Woodland artifacts that suggest trade with Hopewell groups from Ohio. A circular Archaic hearth was uncovered at one meter below surface and similar deep anomalies were seen in the GPR data at this level. A semi-automated object-based image analysis (OBIA) was implemented …


Changes In Land Use Land Cover (Lulc), Surface Water Quality And Modelling Surface Discharge In Beaver Creek Watershed, Northeast Tennessee And Southwest Virginia, Tosin James May 2020

Changes In Land Use Land Cover (Lulc), Surface Water Quality And Modelling Surface Discharge In Beaver Creek Watershed, Northeast Tennessee And Southwest Virginia, Tosin James

Electronic Theses and Dissertations

Beaver Creek is an impaired streams that is not supporting its designated use for recreation due to Escherichia coli (E.coli), and sediment. To address this problem, this thesis was divided into two studies.

The first study explored changes in Land Use Land Cover (LULC), and its impact on surface water quality. Changes in E.coli load between 1997-2001 and 2014-2018 were analyzed. Also, Landsat data of 2001, and 2018 were examined in Terrset 18.31. Mann-Whitney test only showed a significant reduction in E.coli for one site. Negative correlation was established between E.coli load, and Developed LULC, Forest LULC, and …


Debris-Slide Susceptibility Modelling Using Gis Technology In The Great Smoky Mountains National Park, Raja Das Aug 2019

Debris-Slide Susceptibility Modelling Using Gis Technology In The Great Smoky Mountains National Park, Raja Das

Electronic Theses and Dissertations

Debris-slides are one of the most frequently occurring geological hazards in metasedimentary rocks of the Anakeesta ridge in Great Smoky Mountains National Park (GRSM), which often depends on the influence of multiple causing factors or geo-factors such as geological structures, slope, topographic elevation, land use, soil type etc. or a combination of these factors. The main objective of the study was to understand the control of geo-factors in initiating debris-slides using different knowledge and data-driven methods in GIS platform. The study was performed in three steps: (1) Evaluation of geometrical relationship between geological discontinuity and topographic orientation in initiation of …


Geostatistical Analysis Of Potential Sinkhole Risk: Examining Spatial And Temporal Climate Relationships In Tennessee And Florida, Kimberly Blazzard May 2018

Geostatistical Analysis Of Potential Sinkhole Risk: Examining Spatial And Temporal Climate Relationships In Tennessee And Florida, Kimberly Blazzard

Electronic Theses and Dissertations

Sinkholes are a significant hazard for the southeastern United States. Although differences in climate are known to affect karst environments differently, quantitative analyses correlating sinkhole formation with climate variables is lacking. A temporal linear regression for Florida sinkholes and two modeled regressions for Tennessee sinkholes were produced: a general linearized logistic regression and a MaxEnt derived species distribution model. Temporal results showed highly significant correlations with precipitation, teleconnection patterns, temperature, and CO2, while spatial results showed highly significant correlations with precipitation, wind speed, solar radiation, and maximum temperature. Regression results indicated that some sinkhole formation variability could be …


Potential For Developing Run-Of-River Systems In Eastern Kentucky : A Gis Approach To Site Suitability., Thomas Jeffords May 2018

Potential For Developing Run-Of-River Systems In Eastern Kentucky : A Gis Approach To Site Suitability., Thomas Jeffords

Electronic Theses and Dissertations

Coal has a questionable future with the potential exhaustion of available coal. Alternate sources of energy production should be considered, such as hydropower dams, or the more environmentally friendly, Run of River (RoR) hydropower system. This study seeks to answer the question: What is the potential for RoR hydroelectric systems in Eastern Kentucky counties with significant decreases in coal production and employment? I hypothesize that GIS will identify suitable sites within Pike County for RoR systems. Site suitability for Eastern Kentucky was assessed and determined that Pike County did not have a suitable physical environment for RoR systems. The power …


Geologic And Geochemical Characterization Of Cross-Communication Potential Within The Northern Edwards Aquifer System, Texas, Ingrid J. Eckhoff Dec 2016

Geologic And Geochemical Characterization Of Cross-Communication Potential Within The Northern Edwards Aquifer System, Texas, Ingrid J. Eckhoff

Electronic Theses and Dissertations

The Edwards Aquifer is a large, complex groundwater system located throughout Central Texas in association with the Balcones Fault Zone. The San Antonio and Barton Spring segments of the Edwards Aquifer have been extensively studied in the past because they provide groundwater resources to the largely urbanized areas of San Antonio and Austin, respectively, and smaller communities along the Interstate 35 corridor. Previous research has been conducted on these southern and central portions of the Edwards Aquifer system, which have characterized the structural, hydrogeological and geochemical variations within the highly karsted region. However, the Northern Segment of the Edwards Aquifer …


Tornado Density And Return Periods In The Southeastern United States: Communicating Risk And Vulnerability At The Regional And State Levels, Michelle Bradburn Aug 2016

Tornado Density And Return Periods In The Southeastern United States: Communicating Risk And Vulnerability At The Regional And State Levels, Michelle Bradburn

Electronic Theses and Dissertations

Tornado intensity and impacts vary drastically across space, thus spatial and statistical analyses were used to identify patterns of tornado severity in the Southeastern United States and to assess the vulnerability and estimated recurrence of tornadic activity. Records from the Storm Prediction Center's tornado database (1950-2014) were used to estimate kernel density to identify areas of high and low tornado frequency at both the regional- and state-scales. Return periods (2-year, 5-year, 10-year, 25-year, 50-year, and 100-year) were calculated at both scales as well using a composite score that included EF-scale magnitude, injury counts, and fatality counts. Results showed that the …


Speleogenesis Of Critchfield Bat Caves And Associated Hydrogeology Of The Northern Edwards Aquifer, Williamson County, Texas, Ashley N. Landers May 2016

Speleogenesis Of Critchfield Bat Caves And Associated Hydrogeology Of The Northern Edwards Aquifer, Williamson County, Texas, Ashley N. Landers

Electronic Theses and Dissertations

Karst development in the Edwards Aquifer has been significantly studied in the San Antonio and Barton Spring Segments; however, karst development remains poorly studied in the Northern Segment. Detailed characterization of the Northern Segment is vital for future water conservation because of increasing urban sprawl along the Interstate 35 corridor. The Northern Segment of the Edwards Aquifer consists of Lower Cretaceous strata of the Comanche Peak, Edwards, and Georgetown formations. The stratigraphy is dominated by Edwards Limestone as it is the only formation that crops out in the study area.

Karst, stratigraphic, GIS, and geochemical studies were conducted to evaluate …


Ecological Niche Modeling Of The North American Giant Salamander: Predicting Current And Future Potential Distributions And Examining Environmental Influences, Selena S. Roark May 2016

Ecological Niche Modeling Of The North American Giant Salamander: Predicting Current And Future Potential Distributions And Examining Environmental Influences, Selena S. Roark

Electronic Theses and Dissertations

North American Giant Salamanders (Cryptobranchus alleganiensis), commonly known as hellbenders, have been experiencing a population decline for decades due to human influences, such as pollution and habitat destruction. Many efforts are underway to save the hellbender but their entire potential geographical range has not been well-studied. Currently, hellbender populations are delineated by county boundaries and are on the International Union for Conservation of Nature Red List. The Genetic Algorithm for Rule-set Production, an Ecological Niche Model, was used to model the current hellbender potential distribution at a macro-scale under two different environmental scenarios. Additionally, future potential distributions were …


Effects Of Watershed Characteristics On Stream Vulnerability To Urbanization: Implications Of Future Land Use On Streams In Maine, Usa, Kristen Weil Mar 2016

Effects Of Watershed Characteristics On Stream Vulnerability To Urbanization: Implications Of Future Land Use On Streams In Maine, Usa, Kristen Weil

Electronic Theses and Dissertations

Catchment urbanization has deleterious effects on freshwater resources and aquatic communities in small stream ecosystems. In the State of Maine, many streams have been negatively affected by urbanization and are in need of management and restoration. Impervious cover (IC), i.e., any surface that impedes water infiltration into the ground, can serve as a measure of watershed urbanization. Recent studies conducted in Maine have indicated that stream biotic community structure and function begin to decline at impervious cover levels of approximately 1 to 15%. This wide range presents a challenge to regulatory agencies and watershed managers charged with protecting stream quality …