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Full-Text Articles in Environmental Sciences

Effect Of Elevated Temperature And Roundup Exposure On Oxidative Stress And Antioxidant Status In The American Oyster, Afsana Chowdhury May 2023

Effect Of Elevated Temperature And Roundup Exposure On Oxidative Stress And Antioxidant Status In The American Oyster, Afsana Chowdhury

Theses and Dissertations

Aquatic organisms are frequently exposed to various environmental stressors. In this study, we observed the short-term (1-week) combined dose-dependent effect of Roundup, a glyphosate-based herbicide, and high temperature (30°C) on the morphology of gills and digestive glands, expression of heat shock protein-70 (HSP70), dinitrophenyl protein (DNP), nitrotyrosine protein (NTP), antioxidant enzymes such as catalase (CAT) and superoxidase dismutase (SOD) in tissues of American oyster (Crassostrea virginica). Histological analyses showed an increase in mucous production in the gills and digestive glands, hemocyte aggregation in the connective tissues as well as structural change of the lumen in the digestive glands …


Flow Monitoring And Tidal Exchange Ratio Estimation For The Bahia Grande After Widening Of The Carl Joe Gayman Pilot Channel: Bahia Grande, Cameron County, Tx, Sabas Lopez Iii May 2023

Flow Monitoring And Tidal Exchange Ratio Estimation For The Bahia Grande After Widening Of The Carl Joe Gayman Pilot Channel: Bahia Grande, Cameron County, Tx, Sabas Lopez Iii

Theses and Dissertations

The Bahia Grande (BG) is an 8,500-acre set of coastal bays and wetlands located between Brownsville and Port Isabel, Tx, near the Gulf of Mexico (GOM) coastline. In 2005, the Carl Joe Gayman Pilot Channel was constructed to address hypersalinity concerns that resulted from natural and anthropogenically-caused tidal isolation since the early 1940’s. In 2022, the Texas General Land Office (GLO) increased the channel’s width and depth in anticipation of increasing tidal exchange ratios by a factor of two to three. Once the channel widening was complete, two SL-1500-3G side-looking acoustic doppler current profilers (ADCPs) were periodically deployed beneath the …


Long-Term Spatial And Temporal Assessment Of Criteria Air Pollutants Concentration Trends In The Lower Rio Grande Valley Region Of Texas, Usa, Md Salahuddin Majumder May 2023

Long-Term Spatial And Temporal Assessment Of Criteria Air Pollutants Concentration Trends In The Lower Rio Grande Valley Region Of Texas, Usa, Md Salahuddin Majumder

Theses and Dissertations

Air pollution is a substantial environmental challenge all over the world. This study investigated the long-term air pollution levels in the Lower Rio Grande Valley region, by utilizing data collected from five continuous ambient monitoring stations in two counties over 23 years, from January 2000 to December 2022, to analyze daily, monthly, and seasonal variations of different pollutants, including ground-level ozone, particulate matter, and carbon monoxide. This study also identified distinct daily and seasonal patterns for O3, PM2.5, PM10, and CO at each monitoring site, influenced by factors such as traffic emissions, temperature, solar radiation, indoor heating, and weather conditions. …


Study Of Trace Elements In Southern Nevada Spring Waters And Lakes, Hyejeong Lee May 2023

Study Of Trace Elements In Southern Nevada Spring Waters And Lakes, Hyejeong Lee

UNLV Theses, Dissertations, Professional Papers, and Capstones

Comprehending the natural water resource is imperative for the entire state of Nevada and of particular significance for Southern Nevada, where rapid population growth and climate change are placing significant strain on supplies. This research underscores the significance of water chemistry in identifying potential water source areas through trace elements. For the first time, the study proposed measuring the compositions of the entire suite of metal elements, ranging from Li to U, in over 40 springs in the Moapa Valley and its upper gradient valleys, utilizing the iCAP Qc ICP-MS (Inductively Coupled Plasma Mass Spectrometer) at UNLV. The research evaluated …


Regeneration Of Quaking Aspen And Understory Vegetation Change After Fire Risk Reduction Treatment, Allison M. Trudgeon May 2023

Regeneration Of Quaking Aspen And Understory Vegetation Change After Fire Risk Reduction Treatment, Allison M. Trudgeon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Quaking aspen (Populus tremuloides Michx.) is a keystone species that, when coexisting with conifers (i.e., seral aspen), often undergoes stand-replacing disturbances to sustain long term vigor. Historically, mixed-to-high severity fire reduced fuels and regenerated aspen, but such disturbances have become less common in recent decades. This has often led to high fuel loading, and many seral aspen stands are at now risk of an unpredictable, high-severity fire, posing a threat to development in the wildland-urban-interface. The lack of a commercial market for aspen, and the risk of conducting prescribed fire, means there are few alternate management options. This has …


Impacts Of Preferential Flow On Tc-99and Np-237 Vadose Transport In Soils At The Savannah River Site, Josh Parris May 2023

Impacts Of Preferential Flow On Tc-99and Np-237 Vadose Transport In Soils At The Savannah River Site, Josh Parris

All Theses

Since the 1950s, the United States has produced approximately 90,000 metric tons of spent nuclear fuel (SNF) (Office of Nuclear Energy, 2022); however, no long-term storage solutions are available. Technecium-99 and neptunium-237, two fission products found in SNF, readily form highly mobile species in oxidizing conditions (Hu, 2008; Bondietti, 1979) and have respective half-lives of 2.13 x 105 and 2.14 x106 years (Hu, 2010). Considering these characteristics, 99Tc and 237Np are two risk-driving isotopes found in SNF storage. The process of macropore-facilitated preferential flow, transport through cracks within a soil matrix, has been recognized to increase …


Investigating Barriers To Conservation Of Freshwater Mussels In South Carolina, Olivia Poelmann May 2023

Investigating Barriers To Conservation Of Freshwater Mussels In South Carolina, Olivia Poelmann

All Theses

Freshwater mussels are a diverse group of filter-feeding bivalves inhabiting freshwater systems; however, ~70% of U.S. species are imperiled. Many freshwater mussel species use fish hosts to complete juvenile transformation making host fish knowledge important for conservation efforts like captive propagation. While captive propagation programs have produced thousands of juveniles, survival post-release into natural systems is poorly studied. To address these absences of information, my first objective was to investigate differences among host use of naturally infested fishes and timing of larval release. My second objective was to evaluate survivorship of laboratory propagated juvenile Carolina Heelsplitter (Lasmigona decorata), …


The Intersection Of Urban Heat Islands And The Cdc Social Vulnerability Index In Two Border Cities, Ileana Morales May 2023

The Intersection Of Urban Heat Islands And The Cdc Social Vulnerability Index In Two Border Cities, Ileana Morales

Open Access Theses & Dissertations

No abstract provided.


Xylitol As A Phase Change Material: Exploring The Replacement Of Erythritol By Xylitol As A Phase Change Material, Elsa C. Micklin May 2023

Xylitol As A Phase Change Material: Exploring The Replacement Of Erythritol By Xylitol As A Phase Change Material, Elsa C. Micklin

Physics

To circumvent the cost and environmental damage associated with batteries, phase change materials have been employed in solar cookpots to enable cooking in unfavorable weather conditions. Researchers at Cal Poly have traditionally employed the sugar alcohol erythritol as a PCM due to its high latent heat and a fusion point above the boiling point of water, but have discovered issues with the polyol’s degradation over extended periods of cycling. This paper explores the viability of erythritol’s sister-compound xylitol as a PCM in insulated solar-electric cookers, or ISECs. An ISEC was constructed with a xylitol PCM, and the data collected from …


Molecular Evidence For The Export Of Terrigenous Organic Matter To The North Gulf Of Mexico By Solid-State 13C Nmr And Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Of Humic Acids, Sarah Ann Ware May 2023

Molecular Evidence For The Export Of Terrigenous Organic Matter To The North Gulf Of Mexico By Solid-State 13C Nmr And Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Of Humic Acids, Sarah Ann Ware

Chemistry & Biochemistry Theses & Dissertations

Marine organic matter is mainly believed to originate from autochthonous organic matter, while terrigenous organic matter is assumed to be largely degraded prior to reaching the open ocean or more recently replaced by marine organic matter via a stripping process. Sediment samples along a transect extending from the Mississippi River Birdsfoot Delta to the Mississippi Canyon on the Louisiana continental shelf were examined by advanced analytical techniques, electrospray ionization coupled to a 12T Fourier transform ion cyclotron resonance mass spectrometer (ESI-FTICR-MS) and quantitative solid-state multiple cross polarization magic angle spinning (multi-CPMAS) 13C NMR in an effort to understand the …


Morphologic Comparisons Of Recrystallized And Neocrystallized Fibrous Amphibole Asbestos: Implications For Corresponding Health Risk Potential, Natalie G. Renkes May 2023

Morphologic Comparisons Of Recrystallized And Neocrystallized Fibrous Amphibole Asbestos: Implications For Corresponding Health Risk Potential, Natalie G. Renkes

UNLV Theses, Dissertations, Professional Papers, and Capstones

The presence of naturally-occurring asbestos (NOA) is increasingly concerning for scientists, health and regulatory agencies, and citizens living in impacted areas. It is commonly believed that fibrous amphibole asbestos can only form through neocrystallization. In southern Nevada, NOA occurs as a result of hydrothermal alteration of granitic rock producing fibrous amphibole both as cross-cutting neocrystallized veins and via recrystallization of original magmatic hornblende crystals. Fibers with a greater aspect ratio are known to have increased toxicity. This study measured the maximum length and average width of both neocrystallized and recrystallized fibers to see if the morphologies were similar. Neocrystallized and …


A One-Dimensional Analysis Of A Microbial Fuel Cell For Efficient Acetate Removal And Power Density Output, David Rouhani May 2023

A One-Dimensional Analysis Of A Microbial Fuel Cell For Efficient Acetate Removal And Power Density Output, David Rouhani

UNLV Theses, Dissertations, Professional Papers, and Capstones

Microbial fuel cells (MFCs) are electrochemical devices that utilize microorganisms to convert organic matter into electrical energy. MFCs have been discussed to have potential application for sustainable wastewater treatment due to their ability to generate electricity while simultaneously treating contaminated water. To optimize MFC performance, numerical models can be used to understand the complex electrochemical and biological processes occurring in the system. In this study, a numerical model was developed to simulate the performance of MFCs under varying operating conditions and to investigate the performance of a MFC for treating wastewater fuel. More specifically, the MFC was modeled to oxidize …


The Impact Of Glacial Proximity On The Elemental Composition Of Leachate Derived From Sediment Weathering, Karoline Ford May 2023

The Impact Of Glacial Proximity On The Elemental Composition Of Leachate Derived From Sediment Weathering, Karoline Ford

Theses/Capstones/Creative Projects

This study assesses chemical weathering trends as they relate to glacial retreat. The chemical environment of surfaces exposed to the atmosphere differs significantly from beneath a glacier. As a glacier melts, changes to the biogeochemical processes generate environmental gradients. This study analyzed chemical weathering signals at different distances from a glacial front by comparing the elemental composition of leachate derived from sediments in southeastern Greenland. Samples from proglacial, nonglacial, and moraine locations were weathered in a laboratory setting, and ion chromatography was used to determine the elemental composition of the products. Divergent trends in leachate composition were observed as distance …


Fabrication Of Solid Oxide Fuel Cell Components Using Stereolithography 3d Printing, Hannah Dyer May 2023

Fabrication Of Solid Oxide Fuel Cell Components Using Stereolithography 3d Printing, Hannah Dyer

Mechanical & Aerospace Engineering Theses & Dissertations

Transitioning from fossil fuel supplied energy to renewable technology must meet cost efficient parameters throughout the manufacturing process while possessing the characteristics of a functioning and reliable power source. With a significant demand in renewable energy products, developmental techniques require adaptive approaches and procedures for novel materials in the manufacturing phase. This report proposes how a solid oxide fuel cell (SOFC), a renewable energy system, can employ additive manufacturing for directly 3D printing its components by utilizing stereolithography (SLA) 3D printing techniques. Fabrication of the printed components from the mixtures were first mixed with varying concentrations of ceramic powder and …


Mapping Past Land Use Changes And Modeling Future Urbanization Patterns In A Mid-Sized American City, Duncan P. Mccurry May 2023

Mapping Past Land Use Changes And Modeling Future Urbanization Patterns In A Mid-Sized American City, Duncan P. Mccurry

Masters Theses

On a global scale, humans have been moving from rural to urban areas at an increasingly fast rate in a process called urbanization. It is crucial to understand and predict the impacts of urbanization because city expansion encroaches on farmland and woodland, reducing regional ecosystem services. Therefore, urbanization must be well planned in a forecasting manner. The objective of this study is to map the land use change in Knox County, Tennessee, from 2001-2019 to identify the urbanization trends and understand the dynamic geospatial relationships between the urban and rural areas. The geospatial mapping was done using USGS land use …


Closing The Loop Of Food Systems: Analyzing Compost Within Community Bounds, Ellen A. Getter May 2023

Closing The Loop Of Food Systems: Analyzing Compost Within Community Bounds, Ellen A. Getter

Honors Theses

The aim of this thesis is to construct a philosophical and ecological argument that places great value on localized food systems in terms of waste. This composition develops the claim that building composting infrastructure on a community scale will curb the global climate crisis and enhance the interconnectedness humans have within themselves, each other, and the natural world. The first prong of this thesis entails a theoretical framework we must function under in order to implement such radical food revolutions in our communities informed by Buddhist principles. This proceeds an international case study of the composting infrastructure of Fort Albany …


Desert Spring Prokaryotes And Benthic Macroinvertebrates: Geological And Ecological Controls, Ariel D. Friel May 2023

Desert Spring Prokaryotes And Benthic Macroinvertebrates: Geological And Ecological Controls, Ariel D. Friel

UNLV Theses, Dissertations, Professional Papers, and Capstones

Desert springs are aquatic oases, being considered among the most diverse and imperiled ecosystems on Earth. Despite the ecological significance and threatened status of desert springs, few studies have surveyed the microorganisms in these systems or their interactions with other community members. The primary goal of this dissertation was to describe the major controls influencing the community ecology of prokaryotic and BMI communities in cold- and moderate-temperature desert springs of the southern hydrographic Great Basin. Chapter 1 provides a broad overview of spring ecosystems and of each chapter included in this dissertation. Chapter 2 documents the first-ever, regional-scale survey of …


The Effects Of Habitat Isolation On Fine-Scale Genetic And Geographic Structure Of Populations Of Two Threatened Endemic Insects In Southern Nevada, Pseudocotalpa Giulianii And Icaricia Shasta Charlestonensis, Kristen Tovar May 2023

The Effects Of Habitat Isolation On Fine-Scale Genetic And Geographic Structure Of Populations Of Two Threatened Endemic Insects In Southern Nevada, Pseudocotalpa Giulianii And Icaricia Shasta Charlestonensis, Kristen Tovar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Assessing the role geographic isolation and ecological specialization have on phylogeographic patterns contributes to our understanding of the evolutionary history of a species and the processes that erode genetic diversity. I used mitochondrial and nuclear genomic sequences to assess whether habitat isolation has shaped the fine-scale patterns of present-day genetic structure and diversity in two threatened insect species endemic to southern Nevada. Pseudocotalpa giulianii (Coleoptera; Scarabaeidae) is a dune obligate scarab beetle endemic to only two small, isolated sand dunes in Nye County, Nevada, with a usable habitat of less than 4.2 km sq that is impacted by on-going degradation. …


Multidimensional Investigation Of Tennessee’S Urban Forest, Jillian L. Gorrell May 2023

Multidimensional Investigation Of Tennessee’S Urban Forest, Jillian L. Gorrell

Doctoral Dissertations

Preserving existing trees in urban areas and properly cultivating urban forest conservation and management opportunities is valuable to the ever-growing urban environment and necessary for creating optimal experiences and educational tools to meet the needs of increasing urban populations. This dissertation contains studies investigating several facets of the urban forest, including environmental effects of deforestation and urbanization, tree equity, and urban forest facility management and accessibility. Community education and outreach at arboreta about the importance of the tree canopy can help promote environmental stewardship. A digital questionnaire was electronically distributed to representatives of arboreta certified through the Tennessee Division of …


A Natural Resource Management Plan For The Historic Ramsey House, Brianna Saylor, Cole Oakey, Devin Hevener, Everett Williams, Haley Cox, Rachel Carpenter May 2023

A Natural Resource Management Plan For The Historic Ramsey House, Brianna Saylor, Cole Oakey, Devin Hevener, Everett Williams, Haley Cox, Rachel Carpenter

Chancellor’s Honors Program Projects

No abstract provided.


The Forest Of Claytor Nature Center As A Carbon Offset; Assessing The Sequestration Potential And Socioeconomic Implications, Sarah Mccollum Apr 2023

The Forest Of Claytor Nature Center As A Carbon Offset; Assessing The Sequestration Potential And Socioeconomic Implications, Sarah Mccollum

Graduate Dissertations and Theses

Cap and trade programs limit the amount of emissions an organization can produce. To neutralize unavoidable emissions, organizations can purchase carbon offsets from the carbon market. The ability to quantify greenhouse gas emissions offsets in forests increased the urgency and popularity of the carbon market because carbon dioxide (CO2) has a large role in climate change. The University of Lynchburg’s Claytor Nature Center’s 332-acre forest could be a viable revenue source because of its ability to remove CO2 from the atmosphere. In this research, the potential number of annual offsets from Claytor Forest was measured through a manual biomass survey. …


Balancing Interests In Forest Governance In Brazil And Indonesia, Annabel Mccormick Baldy Apr 2023

Balancing Interests In Forest Governance In Brazil And Indonesia, Annabel Mccormick Baldy

Environment and Sustainability Honors Papers

Forests play a major role in reducing levels of Greenhouse gasses which are a major contributor to global warming. Conversely, deforestation is a major contributor to climate change. This study examines the concept of good forest governance, dispelling notions that resource use needs to be a zero-sum game. Rather, it identifies local collective agreements as espoused by Elinor Ostrom in Governing the Commons as the best means of balancing the undeniable economic potential of converting forests to other uses (grazing, farming, and mining) with the more sustainable approach of protecting forests for their environmental benefit. For Ostrom, these collective agreements …


The Bellarmine Bee Bed: Organizing A Native Plant Garden Using Feedback From The Local Community, Kate Moran Apr 2023

The Bellarmine Bee Bed: Organizing A Native Plant Garden Using Feedback From The Local Community, Kate Moran

Undergraduate Theses

Animal pollinators are the cornerstone of healthy ecosystems. Their survival is essential for the persistence of entire food chains: from the flowers they cross-pollinate directly, to the animals who depend on those plants for nutrition. The establishment of pollinator gardens—particularly ones that consist of native plants—is an effective way to enhance their biodiversity, abundance, and well-being.

The main goal of this thesis is to construct a pollinator garden that maximizes the benefits for animal pollinators using feedback from local gardeners. A survey was used to gather information about the popularity and preferences of 40 flowering plants, and after analyzing the …


Race, Gender And Rawls' "A Theory Of Justice.", Robert Carico Apr 2023

Race, Gender And Rawls' "A Theory Of Justice.", Robert Carico

Honors Theses

Should we use the concepts developed by John Rawls in his A Theory of Justice to guide research questions relevant to issues concerning race and gender? This paper argues not only that the concepts from A Theory of Justice should not be used as the primary tool in any debate concerning race and gender, but it also challenges the abstract thinking of 21st Century Western Philosophers to develop a theory of justice that acknowledges the fact that people have their own interests and depending on what race and/or gender they identify with, might not have equal rights protected under the …


The Public Trust Doctrine: Roman Law Roots And Future In Environmental Litigation, Phoebe Liccardo Apr 2023

The Public Trust Doctrine: Roman Law Roots And Future In Environmental Litigation, Phoebe Liccardo

Honors Theses

The public trust is an ancient and enduring legal doctrine. With roots in Roman law, the public trust persists through English law, and into the United States. Scholars and jurists in the field of Roman and environmental law do not all agree on the history and continuity of the public trust doctrine (PTD). There are those who argue the Roman law introducing a public trust did not assert the same protections present in the doctrine today. Conversely, there are those who believe the Roman law did enshrine similar protections, and further, that it calls for an expansion of PTD in …


The History And Significance Of Taxidermy Bird Collections In North America: Bgsu's Own Undervalued Collection And Its Future, Kristin Burnside Apr 2023

The History And Significance Of Taxidermy Bird Collections In North America: Bgsu's Own Undervalued Collection And Its Future, Kristin Burnside

Honors Projects

Taxidermy, despite its association with the bizarre and outlandish, has a rich history and culture that helped to define post-Civil War America and its pursuit of knowledge and reconnection with nature. With the widespread publication and availability of how-to guides, natural history collecting and taxidermy became accessible to any individual regardless of age, gender, or class. The hobby required physicality and courage to collect unique and interesting specimens, and intellect and creativity to conserve and display them, all of which inherently connected the avocation with respect. With varying levels of success, hobbyists experimented with different chemicals, such as arsenic, in …


Impacts Of Urban Renewal On Community Identity And Sense Of Place In Las Cruces, New Mexico, Savannah Lorraine Quintana-Eddins Apr 2023

Impacts Of Urban Renewal On Community Identity And Sense Of Place In Las Cruces, New Mexico, Savannah Lorraine Quintana-Eddins

Geography ETDs

Las Cruces is the second largest city in New Mexico which has experienced exponential growth in the last three decades. The city has been cultivated by a rich history of Native populations, Spanish colonialism, and American democratic government. The culmination of these influences on Las Cruces had much influence on the Mesquite Historic District, the original townsite of Las Cruces. This area is home to many generational families and is adjacent to the downtown Main Street corridor. Downtown was built from the destruction of the Mesquite Historic District caused by waves of urban renewal projects. Through organizing, legislative action and …


Predicting Groundwater Spring Locations From Topographic And Climatic Data Using Maxent Modeling, Ayten Ece Koc Apr 2023

Predicting Groundwater Spring Locations From Topographic And Climatic Data Using Maxent Modeling, Ayten Ece Koc

USF Tampa Graduate Theses and Dissertations

The World Resources Institute reveals that 17 countries face extremely high levels of water stress. Moreover, with increasing population and industrialization, the gap between water supply and demand increases day by day around the world. Groundwater is a key freshwater source, and springs are important resources as they enable to access groundwater. Therefore, it is crucial to monitor, protect, and manage groundwater springs. The first step in spring management is to recognize and define freshwater resources and to determine the locations of groundwater springs that serve as natural discharge points. Traditionally, field studies have been employed to determine the locations …


A Graphical User Interface Using Spatiotemporal Interpolation To Determine Fine Particulate Matter Values In The United States, Kelly M. Entrekin Apr 2023

A Graphical User Interface Using Spatiotemporal Interpolation To Determine Fine Particulate Matter Values In The United States, Kelly M. Entrekin

Honors College Theses

Fine particulate matter or PM2.5 can be described as a pollution particle that has a diameter of 2.5 micrometers or smaller. These pollution particle values are measured by monitoring sites installed across the United States throughout the year. While these values are helpful, a lot of areas are not accounted for as scientists are not able to measure all of the United States. Some of these unmeasured regions could be reaching high PM2.5 values over time without being aware of it. These high values can be dangerous by causing or worsening health conditions, such as cardiovascular and lung diseases. Within …


The Use Of Biological Soil Health Indicators To Quantify The Benefits Of Cover Crops, Alexander Wu Apr 2023

The Use Of Biological Soil Health Indicators To Quantify The Benefits Of Cover Crops, Alexander Wu

Masters Theses

Soils provide many essential functions that support the world. With a decline in soil health, these functions also decrease in efficiency, and can threaten the health of billions of people around the world. Typically, soil health tests do not use biological indicators, however microbes drive and perform vital functions to increase soil health. One way to increase soil health is through the use of cover crops to reduce soil erosion during fallow periods, increasing soil organic matter, as well as collecting nutrients from soil into their biomass. These cover crops are then terminated through various methods such as herbicides, disk …