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Full-Text Articles in Physical Sciences and Mathematics

High-Precision Lead Isotope Analysis On Modern Populations To Determine Geolocation Reliability, Gennifer M. Goad Nov 2018

High-Precision Lead Isotope Analysis On Modern Populations To Determine Geolocation Reliability, Gennifer M. Goad

USF Tampa Graduate Theses and Dissertations

Forensic anthropologists increasingly use chemical isotope analysis in the investigation of unidentified human remains, as biochemical georeferencing continually improves with the development of modern reference data of known origins. Isotope variations in trace elements such as strontium (Sr) and lead (Pb) in human teeth are some of the most useful indicators of past domicile in archaeological research and thus have high potential for modern, forensic applications. In this study, high-precision lead isotope analysis was conducted on 63 modern human teeth, which were previously analyzed for strontium isotopes. The results present new lead isotope data for the following countries: United States …


The Utility Of The Conductivity Mass-Balance Method For Base Flow Separation In Rivers And Streams, Darline Alegria Lott Nov 2018

The Utility Of The Conductivity Mass-Balance Method For Base Flow Separation In Rivers And Streams, Darline Alegria Lott

USF Tampa Graduate Theses and Dissertations

Freshwater for ecosystems, drinking water, and water for various businesses are important resources and those resources are rapidly diminishing globally due to drought and overuse. In order to manage the availability of water for all concerned, good estimates of base flow (groundwater) is required. Base flow, a component of streamflow, is deduced by separating a stream hydrograph into two components, base flow and runoff. There are several techniques used to perform base flow separation; however two techniques are used in this study, chemical mass-balance and analytical methods. This dissertation explains how an analytical technique was derived from a mass-balance method, …


Assessing The Cooling Effects Of Urban Vegetation On Urban Heat Mitigation In Selected U.S. Cities, Qiuyan Yu Nov 2018

Assessing The Cooling Effects Of Urban Vegetation On Urban Heat Mitigation In Selected U.S. Cities, Qiuyan Yu

USF Tampa Graduate Theses and Dissertations

Urban Heat Island (UHI) is a growing problem worldwide. Mitigation of UHI is necessary for cities to adapt to climate change and enhance sustainable development at a city scale. Cooling cities with urban vegetation management is a sustainable solution for urban heat mitigation. Urban vegetation influences urban microclimate through the shading effect, surface roughness, and evapotranspiration. The differences in horizontal and vertical structures of urban vegetation determine the shading effect, surface roughness, and evapotranspiration. Enhancing the cooling effect of urban vegetation requires a comprehensive understanding of how vegetation structure affects UHI. The effects of horizontal structure on land surface temperature …


Enhancement Of Rainfall-Triggered Shallow Landslide Hazard Assessment At Regional And Site Scales Using Remote Sensing And Slope Stability Analysis Coupled With Infiltration Modeling, Thilanki Maneesha Dahigamuwa Rajaguru Mudiyanselage Nov 2018

Enhancement Of Rainfall-Triggered Shallow Landslide Hazard Assessment At Regional And Site Scales Using Remote Sensing And Slope Stability Analysis Coupled With Infiltration Modeling, Thilanki Maneesha Dahigamuwa Rajaguru Mudiyanselage

USF Tampa Graduate Theses and Dissertations

Landslides cause significant damage to property and human lives throughout the world. Rainfall is the most common triggering factor for the occurrence of landslides. This dissertation presents two novel methodologies for assessment of rainfall-triggered shallow landslide hazard. The first method focuses on using remotely sensed soil moisture and soil surface properties in developing a framework for real-time regional scale landslide hazard assessment while the second method is a deterministic approach to landslide hazard assessment of the specific sites identified during first assessment. In the latter approach, landslide inducing transient seepage in soil during rainfall and its effect on slope stability …


Optical Remote Sensing Of Oil Spills In The Gulf Of Mexico, Shaojie Sun Nov 2018

Optical Remote Sensing Of Oil Spills In The Gulf Of Mexico, Shaojie Sun

USF Tampa Graduate Theses and Dissertations

Assessment of oil spills in the ocean using passive remote sensing (i.e., reflected sun light) faces two challenges: detect oil presence/absence and quantify oil volume. While the optical properties of oil allow it to be differentiated from the surrounding marine environment, sun glint can facilitate oil presence/absence detection because the oil-water spatial contrast is enhanced due to wave dampening. However, sun glint also modulates the magnitude and shape of the spectral reflectance of surface oil. In addition to this difficulty, the most critical challenge is how to quantify oil volume (or thickness) through remote sensing. To date, such quantifications have …


Remote Estimation Of Surface Water PCo2 In The Gulf Of Mexico, Shuangling Chen Oct 2018

Remote Estimation Of Surface Water PCo2 In The Gulf Of Mexico, Shuangling Chen

USF Tampa Graduate Theses and Dissertations

Surface ocean partial pressure of CO2 (pCO2) is a critical parameter in the quantification of air-sea CO2 flux, which further plays an important role in quantifying the global carbon budget and understanding ocean acidification. The demand for a clearer understanding of how, and how fast, the ocean is changing due to atmospheric CO2 absorption, requires accurate and synoptic estimation of surface pCO2.

Surface ocean pCO2 is mainly controlled by four oceanic processes – thermodynamics, ocean mixing, biological activities, and air-sea CO2 exchange. Surface ocean pCO2 …


Ice And Guano Deposits In El Malpais Lava Tubes: Potential Paleoclimate Archives For The Southwest United States, Dylan S. Parmenter Oct 2018

Ice And Guano Deposits In El Malpais Lava Tubes: Potential Paleoclimate Archives For The Southwest United States, Dylan S. Parmenter

USF Tampa Graduate Theses and Dissertations

Three ice cores and one guano core were obtained from lava tubes in El Malpais National Monument, New Mexico, in the Southwest United States. A large hiatus in the Bat Cave guano record, resulting from mining activities in the early 1900's, left us with only ~50 years of data (from AD 1955-2006) to use in analysis. 13C values in guano (-18 to -11.6‰) primarily fall within the range of C4 plants, and likely indicate a tendency of Tadarida brasiliensis to feed on insects over grasslands to the North or South of the park. Variations in 13C values for this period …


Morphodynamics Of Shell Key And Mullet Key Barrier Islands: Their Origin And Development, Zachary J. Westfall Oct 2018

Morphodynamics Of Shell Key And Mullet Key Barrier Islands: Their Origin And Development, Zachary J. Westfall

USF Tampa Graduate Theses and Dissertations

Shell Key and Mullet Key are two sandy barrier islands on the West Central Florida coast near the mouth of Tampa Bay. These islands are part of an interconnected barrier-inlet system that includes Pass-a-Grille (PAG) and Bunces Pass. Shell Key is a relatively new island about 40-years of age that formed in between the two inlets of Bunces Pass and PAG. Mullet Key is an island to the south of Shell Key situated between Bunces Pass and the main Tampa Bay channel that has demonstrated large scale upward shoaling events. Using numerical modeling, the wave and tidal conditions at the …


Application Of Image Recognition Technology To Foraminiferal Assemblage Analyses, Christian Helmut Gfatter Oct 2018

Application Of Image Recognition Technology To Foraminiferal Assemblage Analyses, Christian Helmut Gfatter

USF Tampa Graduate Theses and Dissertations

Analyses of foraminiferal assemblages involve time consuming microscopic assessment of sediment samples. Image recognition software, which systematically matches features within sample images against an image library, is widely used in contexts ranging from law enforcement to medical research. At present, scientific applications such as identification of specimens in plankton samples utilize flow through systems in which samples are suspended in liquid and pass through a beam of light where the images are captured using transmitted light. Identification of foraminifers generally utilizes reflected light, because most shells are relatively opaque.

My goal was to design and test a protocol to directly …


Spatial And Temporal Distributions Of Pelagic Sargassum In The Intra-Americas Sea And Atlantic Ocean, Mengqiu Wang Jul 2018

Spatial And Temporal Distributions Of Pelagic Sargassum In The Intra-Americas Sea And Atlantic Ocean, Mengqiu Wang

USF Tampa Graduate Theses and Dissertations

Pelagic Sargassum is one type of marine macroalgae that is known to be abundant in the Gulf of Mexico and Sargasso Sea. It is also known to serve as a critical habitat for many marine animals. In the past few years, large amounts of Sargassum have been reported in the Tropical Atlantic and Caribbean Sea (CS), causing significant environmental and economic problems. The goal of this study is to improve the understanding of Sargassum distributions, quantity, transport pathways, and bloom mechanisms in the CS and Tropic Atlantic through combining a variety of techniques including satellite remote sensing, field and laboratory …


Theory And Application Of Geophysical Geodesy For Studying Earth Surface Deformation, Makan A. Karegar Jul 2018

Theory And Application Of Geophysical Geodesy For Studying Earth Surface Deformation, Makan A. Karegar

USF Tampa Graduate Theses and Dissertations

An interdisciplinary approach at the interface between geodesy and geophysics has recently resolved several Earth science problems at regional and global scales. I use the term “geophysical geodesy” to distinguish the technical and theoretical aspect of geodesy from geophysical applications of geodetic techniques. Using a wide range of Earth observation data, I study the spatio-temporal characteristics of Earth surface deformation in the United States associated with several geophysical processes, including natural and anthropogenic subsidence and uplift, regional relative sea-level rise, and continental hydrological loading. The theoretical portion of this dissertation applies loading theory and develops a new hybrid method to …


Assessing Bald Cypress (Taxodium Distichum) Tree Dynamic Change In Usf Forest Preserve Area Using Mixture-Tuned Matched Filtering And Multitemporal Satellite Imagery, Yujia Wang Jun 2018

Assessing Bald Cypress (Taxodium Distichum) Tree Dynamic Change In Usf Forest Preserve Area Using Mixture-Tuned Matched Filtering And Multitemporal Satellite Imagery, Yujia Wang

USF Tampa Graduate Theses and Dissertations

Wetlands are the most important and valuable ecosystems on Earth. They are called “kidneys of the Earth”. Vegetation change detection is necessary to understand the condition of a wetland and to support ecosystem sustainable management and utilization. It has been a great challenge to estimate vegetation (including bald cypress trees) coverage of the wetland because it is difficult to access directly. Satellite remote sensing technology can be one important feasible method to map and monitor changes of wetland forest vegetation and land cover over large areas. Remote sensing mapping techniques have been applied to detect and map vegetation changes in …


Comparison Of Beach Changes Induced By Two Hurricanes Along The Coast Of West-Central Florida, Ruoshu Zhao Jun 2018

Comparison Of Beach Changes Induced By Two Hurricanes Along The Coast Of West-Central Florida, Ruoshu Zhao

USF Tampa Graduate Theses and Dissertations

The beach profiles pre-and post-the Hurricane Hermine (2016) and Irma (2017) along the Sand Key barrier island were collected to quantify longshore variations in storm induced beach changes as well as to compare the beach changes caused by hydrodynamic conditions of the two different hurricanes.

Cross-shore beach profile are examined in 4 sections including dune field, dry beach, sand bar and whole beach to calculate beach change. The volume change for each section and shoreline contour change before and post the hurricane was computed. Hydrodynamic conditions were obtained from adjacent NOAA’s tide and wave gauges.

Both hurricanes generated high offshore …


An Evaluation Of Marsh Shoreline Erosion And Sediment Deposition In The Grand Bay National Estuarine Research Reserve, Mississippi, Usa, Joseph Terrano Jun 2018

An Evaluation Of Marsh Shoreline Erosion And Sediment Deposition In The Grand Bay National Estuarine Research Reserve, Mississippi, Usa, Joseph Terrano

USF Tampa Graduate Theses and Dissertations

Coastal marshes serve important ecologic and economic functions, such as providing habitat, absorbing floodwaters and storm surges, and sequestering carbon. Throughout the northern Gulf of Mexico, coastal marshes are disappearing due to wave attack, sea-level rise, sediment export, and subsidence. Marsh area increases when sediments accumulate at the marsh shoreline, accrete vertically, and when non-marsh areas are colonized by marsh vegetation. Marsh shoreline erosion results in net marsh loss when transgression rates at the marsh-water edge exceed upland-marsh migration. The balance between marsh destroying and marsh creating processes determines the long-term survivability of a marsh system. Thus, processes of shoreline …


A Comparative Study On Coastal Zone Changes And Anthropogenic Impacts Between Tampa Bay, Usa, And Xiangshan Harbor, China, During The Last 30 Years, Qiandong Guo Jun 2018

A Comparative Study On Coastal Zone Changes And Anthropogenic Impacts Between Tampa Bay, Usa, And Xiangshan Harbor, China, During The Last 30 Years, Qiandong Guo

USF Tampa Graduate Theses and Dissertations

Currently, the U.S. and China are the two largest national economic entities in the world. However, it is noticeable that the two countries have considerably different strategies for economic development, environmental protection and land supply in coastal zones. In order to understand the coastline dynamics, land use land cover (LULC) changes and land management policies in the U.S. and China, a case study of the Tampa Bay (TB) watershed, Florida, U.S., and Xiangshan Harbor (XH), Zhejiang Province, China was conducted. The two areas possess similar humid subtropical climate and dense population, but experienced different anthropogenic impacts. TB sat at a …


Environmental Controls On The Geochemistry Of Globorotalia Truncatulinoides In The Gulf Of Mexico: Implications For Paleoceanographic Reconstructions, Caitlin Elizabeth Reynolds Jun 2018

Environmental Controls On The Geochemistry Of Globorotalia Truncatulinoides In The Gulf Of Mexico: Implications For Paleoceanographic Reconstructions, Caitlin Elizabeth Reynolds

USF Tampa Graduate Theses and Dissertations

Modern observations of planktic foraminifera from sediment trap studies help to constrain the regional ecology of paleoceanographically valuable species. Results from a weekly-resolved sediment trap time series (2008–2014) in the northern Gulf of Mexico demonstrate that 92% of Globorotalia truncatulinoides flux occurs in winter (January, February, and March), and that encrusted and non-encrusted individuals represent calcification in distinct depth habitats. We use individual foraminiferal analysis (IFA) of G. truncatulinoides tests to investigate differences in the elemental (Mg/Ca) and isotopic composition (18O and 13C) of the encrusted and non-encrusted ontogenetic forms of G. truncatulinoides, and to estimate their calcification depth in …


Evaluation Of Academic And Social Engagement In A Technology-Based Collaborative Approach To Inclusive Geoscience Field Learning, Anita Marie Stone Marshall Apr 2018

Evaluation Of Academic And Social Engagement In A Technology-Based Collaborative Approach To Inclusive Geoscience Field Learning, Anita Marie Stone Marshall

USF Tampa Graduate Theses and Dissertations

Field learning is an important aspect of geoscience education to teach or reinforce concepts and skills, and the highly social experience of field work can improve learning outcomes, create networks to support future academic success, and promote a sense of belonging in the geosciences. However, field learning presents significant barriers to participation for students with physical disabilities. The introduction of digital data collection and communication devices into traditional field work settings has created new opportunities to expand access to field learning experiences such as remote collaboration; a method of undertaking field work through collaborative teamwork and the use of digital …


Flow And Transport In Low-Gradient Rivers And Estuaries, Hunter Lee Clasen Apr 2018

Flow And Transport In Low-Gradient Rivers And Estuaries, Hunter Lee Clasen

USF Tampa Graduate Theses and Dissertations

For this dissertation I studied flow and transport in low gradient Florida streams. Chapter 2 is a statewide analysis of long-term variations in stream discharge. The results from Chapter 2 suggest that changes in mean annual stream discharge are controlled by the Atlantic Multi-Decadal Oscillation (AMO). During the warm phase, mean annual discharge decreases in central Florida and increases in north Florida. The opposite is true during the cool phase, with mean annual discharge increasing in central Florida and decreasing in north Florida. This pattern is observed for both components of stream discharge, base flow and runoff.

The following two …


Application Of Modern Foraminiferal Assemblages To Paleoenvironmental Reconstruction: Case Studies From Coastal And Shelf Environments, Christian Haller Mar 2018

Application Of Modern Foraminiferal Assemblages To Paleoenvironmental Reconstruction: Case Studies From Coastal And Shelf Environments, Christian Haller

USF Tampa Graduate Theses and Dissertations

The aim of paleoenvironmental studies is to reconstruct characteristics of the past environment from fossil assemblages preserved in sedimentary strata. Thus, studies of modern surface assemblages, quantitatively correlated to the environmental parameters, are required before reliable interpretations can be made. For this dissertation, two different techniques were applied in two case studies: a reconstruction making use of a benthic foraminiferal transfer function from the intertidal marshes in the eastern Mississippi Sound, Alabama/Mississippi, and a qualitative reconstruction of ocean current activity on the Western Australian shelf.

Modern salt-marsh foraminifera were collected from Grand Bay, Pascagoula, Fowl River, and Dauphin Island across …


Remote Sensing And Spatial Metrics For Quantifying Seagrass Landscape Changes: A Study On The 2011 Indian River Lagoon Florida Seagrass Die-Off Event, René Dieter Baumstark Mar 2018

Remote Sensing And Spatial Metrics For Quantifying Seagrass Landscape Changes: A Study On The 2011 Indian River Lagoon Florida Seagrass Die-Off Event, René Dieter Baumstark

USF Tampa Graduate Theses and Dissertations

Florida’s seagrasses are ecologically important marine environments which have suffered major degradation caused by increasing anthropogenic pressures. A 2011 seagrass die-off event caused by an algal bloom in the Florida Indian River Lagoon (IRL) was particularly severe with a majority of seagrass lost in areas such as the Banana River. An understanding of how this coastal marine environment changed is an important step toward better managing resources for conservation. Modern tools and methods provide new opportunities to study these changes at the landscape scale, a scale that informs on the larger more comprehensive state of a system. Classified satellite imagery …


Geochemical Modeling Of Primary Morb Magmas: Implications For Parental Melting Regimes In Melt Lenses Along-Axis Of The Hess Deep Rift, Stephanie Michelle Drumm Mar 2018

Geochemical Modeling Of Primary Morb Magmas: Implications For Parental Melting Regimes In Melt Lenses Along-Axis Of The Hess Deep Rift, Stephanie Michelle Drumm

USF Tampa Graduate Theses and Dissertations

The Hess Deep Rift in the East Pacific Rise is a mid-ocean ridge spreading center that produces melts which exhibit geochemical characteristics of evolved MORB. Using basaltic glass samples collected from multiple dive cruises that explored Hess Deep geology, volatile and chemical data were collected at USF using FTIR and EMPA, respectively. In addition, a data suite of samples of glass from Hess Deep were compiled from the EarthChem database. The intention was to use the data suite and models to compare the Hess Deep regime to analog models for mid-ocean ridge crystallization regimes and tectonic structures. The USF and …


The Stability Of Sand Waves In A Tidally-Influenced Shipping Channel, Tampa Bay, Florida, John Willis Gray Mar 2018

The Stability Of Sand Waves In A Tidally-Influenced Shipping Channel, Tampa Bay, Florida, John Willis Gray

USF Tampa Graduate Theses and Dissertations

Tidally-influenced sandwaves are common coastal features present in various settings, including shipping channels. The main shipping channel in Tampa Bay under the Bob Graham Sunshine Skyway Bridge (a.k.a. the Skyway Bridge) contains such sandwave bedforms. Between the years 2000 and 2017, these bedforms have been surveyed with multibeam echosounders (MBES) on 21 occasions with ranging coverage and quality of returns. Surveys between 2000 and 2009 used a 300 kHz Kongsberg EM3000; surveys between 2015 and 2017 used a 400 kHz Reson Seabat 7125. For comparable surveys, bathymetry, backscatter, slope, curvature, planform curvature, and profile curvature maps were created and analyzed. …


Quantifying The Effect Of Topographic Slope On Lava Flow Thickness: A First Step To Improve Lava Flow Volume Estimation Methods, Steven R. Rizo Mar 2018

Quantifying The Effect Of Topographic Slope On Lava Flow Thickness: A First Step To Improve Lava Flow Volume Estimation Methods, Steven R. Rizo

USF Tampa Graduate Theses and Dissertations

The volume of lava flows provide important information on the magnitude of volcanic eruptions, and accurate volumes are necessary to produce reliable models of lava flow emplacement or constrain the internal structure of volcanoes. The most accurate lava flow volumes are obtainable when the topography before and after an eruption are both known, but information for the topography before lava flow emplacement is absent in non-historic lava flows. To calculate the volume of non-historic lava flows, this pre-emplacement topography needs to be reconstructed. Common methods for this include using inverse distance-weighted averages or global polynomial interpolation methods, but these can …