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Methods To Improve The Remediation Of Polycyclic Aromatic Hydrocarbons (Pahs) In Aerobic And Anaerobic Environments, Brian Wartell

Dissertations

Oil spills occur regularly in terrestrial environments and crude oil can contain many compounds that are highly resistant to degradation. Among these compounds are high levels of polycyclic aromatic hydrocarbons (PAHs) which are not only toxic but can also be carcinogenic and/or mutagenic. The first chapter of this dissertation includes an extensive review chapter on the variables affecting the anaerobic degradation of hydrocarbons, with a particular focus on PAHs. Electron acceptors, electron donors, temperature, salinity, pH all play key roles in determining the possibility effective of effective degradation occurring. Thus, by addressing solutions, such as biostimulation, improving environmental variables for …

An Acoustic Monitoring Method For Assessing River Dolphin Presence And Changes In The Context Of Anthropogenic Development, Charles A. Muirhead

Graduate Masters Theses

Populations of river dolphins throughout Asia are in decline as a direct result of intensified anthropogenic activity along river systems. Water development projects, land use change, contamination, and intensified fishing practices are known factors contributing to the probable extinction of the Yangtze river dolphin (Lipotes vexillifer) and declining populations of the South Asian river dolphin (Platanista gangetica spp.), Irrawady dolphin (Orcaella brevirostris), and finless porpoise (Neophocaena a. asiaeorientalis). Although not yet as extensive, river system development in South America is following a similar path as that of Asia, with impacts on dolphin species likely to follow. Currently, the Amazon river …

A View From Within: Notes And Insight From An Institutional Ethnography Of The National Commission For Natural Protected Areas In Tulum, Mexico, Maxwell J. Martin

Graduate Masters Theses

National parks and protected areas are an integral component of the Mexican government’s long-term natural resource conservation strategy. They comprise over 90 million hectares throughout the country. However, the establishment and upkeep of these protected areas often incites conflict both between and among local actors. From poachers taking protected resources to indigenous peoples exercising their rights, protected areas have become a source of political, economic, and moral contention across the globe. In addition, their effectiveness in either ecological or sustainable development terms has been ambiguous at best.

Tulum, Mexico exemplifies this dilemma. The site of pre-Columbian Mayan architecture, Tulum is …

Effects Of Increasing Temperature And Acidification On The Growth And Competitive Success Of Alexandrium Catenella From The Gulf Of Maine, Drajad Seto

Electronic Theses and Dissertations

The increases in ocean temperature and pCO2 due to climate change are projected to affect the growth and future prevalence of Harmful Algal Blooms (HABs) in nearshore waters, but systematic studies on the effects these climate drivers have on harmful algal species are lacking. In particular, little is known about how future climate scenarios will affect the growth of the toxic dinoflagellate Alexandrium catenella, which produces the toxins responsible for paralytic shellfish poisoning (PSP) that threaten the health and economy of coastal communities in the Gulf of Maine. I examined growth responses of A. catenella and two other naturally co-occurring …

Stream Dynamics In The Headwaters Of Post-Glacial Watershed Systems, Brett Gerard

Electronic Theses and Dissertations

This dissertation summarizes research examining watershed processes across Northern New England, with an emphasis on the Central and Coastal regions of Maine. The research presented here focuses on the linkages between watershed geomorphic conditions, climate, and surface flow regimes driving stream channel hydraulic conditions and bed dynamics governing channel geometry. The geologic and human history of the landscape provides the context in which earth surface processes are examined within the dominant physiographic settings in Maine to describe vulnerabilities to climate change. Results are summarized to support the development of sustainability solutions for forecasted watershed management problems by natural resource management …

The Effects Of Sediment Properties On Barrier Island Morphology And Processes: A Numerical Modeling Experiment, Brittany Kime

University of New Orleans Theses and Dissertations

Barrier island restoration and nourishment is necessary for sustaining coastal systems worldwide. In the Mississippi River Delta Plain, the lack of sediment supply, relative sea level rise, and reworking of abandoned delta lobes promote rapid disintegration of barriers, which can contribute to mainland storm impacts. Barrier island restorations that utilize higher quality sediments (Outer Continental Shelf- OCS) are expected to exhibit higher resiliency, withstanding coastal erosion, event-induced erosion, and ongoing transgression when compared to barriers nourished using lower quality nearshore (NS) sands. Additionally, use of OCS sediments increases sediment supply by adding material to the system supporting increased barrier longevity …

Long-Term Variation Of Summer Phytoplankton Communities In An Urban Lake In Relation To Lake Management And Climate Conditions, Yuan Xiao Grund

Dissertations and Theses

Eutrophication is one of the primary factors causing harmful cyanobacteria blooms in freshwater lakes; climate change such as warmer temperature can potentially further increase both frequency and intensity of blooms. This study investigated the long-term changes in water quality and summer phytoplankton assemblages in Oswego Lake, OR, in relation to lake management practices (e.g., hypolimnetic aeration and alum treatments), as well as climatic and regional meteorological conditions. Both water quality and phytoplankton assemblages were sampled biweekly during summer seasons between 2001 and 2013. The concentrations of total phosphorus (TP), soluble reactive phosphorus (SRP) and total nitrogen (TN) decreased 66%, 93% …

Mercury In Big Cypress Bayou And Caddo Lake Watersheds In Marion And Harrison Counties Texas, Joseph Watkins

Electronic Theses and Dissertations

Caddo Lake has been included on the Texas Commission on Environmental Quality 303(d) list for impairment due to mercury (Hg) content since 1996. One of the primary tributaries, Big Cypress Bayou, flows across Eocene-aged rocks and sediments associated with the Wilcox Group; the Wilcox is of interest because it contains lignite coal, which has a direct link to mercury. Previous research has focused on dry deposition from fossil fuel combustion as the primary source of mercury but has not addressed the potential watershed contribution to mercury concentrations in Caddo Lake.

Big Cypress Bayou flows through Harrison and Marion counties in …

Employee Perceptions Of Organizational Corporate Responsibility And Their Effect On Employee Organizational Commitment, Lisa R. Davis

UNLV Theses, Dissertations, Professional Papers, and Capstones

The debate over whether organizations play a part in society beyond economic profit has been a major focus of research in corporate social responsibility (CSR). These debates have been mainly looked at from the macro (societal) or the meso (institutional) level. Very little research has been done on the role of the firm and looking at CSR from the micro (individual) level. Questions regarding the role of work for employees, securing economic benefits or making a difference in the world, would vary greatly depending on the individual and the importance they place on these areas in their own lives. Scholars …

Design And Preliminary Evaluation Of A Supercritical Carbon Dioxide Brayton Cycle For Solar Dish Concentrator Clean Energy Production, Danielle Nobles-Lookingbill

UNLV Theses, Dissertations, Professional Papers, and Capstones

As we move toward energy independence and more ambitious clean energy goals, solar energy research must push the efficiency limits of traditional energy generation systems. Increases in efficiency can be achieved by increasing the hot temperature of the power cycle. Recent research demonstrates the potential for increased efficiency and a vastly smaller component size when supercritical carbon dioxide Brayton power cycles are used. Concentrated solar and nuclear heat sources are capable of achieving the high working fluid temperatures needed for significant efficiency gains. This NSF EPSCoR funded, experimental research system is designed to exploit the uniquely immense solar irradiance of …

Human Thermal Comfort In Transition Space, Asawari Anil Pawar

UNLV Theses, Dissertations, Professional Papers, and Capstones

ABSTRACT

HUMAN THERMAL COMFORT IN TRANSITION SPACES

Objective: To evaluate and identify the relationship between personal factors and the climatic conditions that influence the human thermal comfort in transition spaces and suggest solutions for adaptation of the built environment, that would encourage active and healthy living in the tourist as well as local community.

Background:

By 2050, there is a prediction that two-thirds of the world population will be living in urban areas, which would add more than 2.5 billion people living in cities (Melnikov et al., 2017). Since Las Vegas is one of the fastest growing cities in Nevada, …

The Use Of Chemical Element Fingerprints To Investigate The Transformation Of Lake Sediments To Land Soils In Drying Lakes: A Case Study At Lake Mead, Nevada, Ji Hye Park

UNLV Theses, Dissertations, Professional Papers, and Capstones

Drying lakes are a worldwide catastrophe. The goals of this dissertation research were (1) to investigate whether chemical fingerprints of lake sediments, and nearby land soils, could be established by the analysis of 44 chemical elements, moisture content, Eh, pH, and leachable anions and if so, (2) whether the fingerprints could help explain the process of physical and chemical changes in the lake sediments as they became soils when the lake's water level fell and the anoxic sediments were exposed to the air and weather.

Lake Mead was chosen to model drying lakes because its water level has fallen over …

Towards Engineering Advanced Nanomaterials: Elucidating Fundamental Particle Behavior In Water And Critical Sorption Dynamics, Changwoo Kim

McKelvey School of Engineering Theses & Dissertations

As advanced nanomaterials, inorganic-organic nano composites have received great interest as potential platform (nano) structures for sensor, catalyst, sorbent, and environmental applications. Here, my Ph.D. research has focused on the design, synthesis, and characterization of advanced water-stable engineered metal-oxide nanoparticles functionalized by organic frames for environmental applications. For the environmental applications, I have evaluated particleoptimized sorption processes for the remediation and separation of arsenic, chromium, and uranium under environmentally relevant conditions. More specifically, I have explored the critical role of organic coating on sorption mechanisms and performances using engineered iron oxide -based, manganese oxide -based, and manganese ferrite -based (core) …

Influencing Hawai‘I Hotel Patrons To Use Reef-Safe Sunscreens, Rochelle Good

UNLV Theses, Dissertations, Professional Papers, and Capstones

The health of Hawaiian coral reefs is threatened by pollution from common sunscreen ingredients such as oxybenzone. Hawai‘i hotel patrons using sunscreens with harmful ingredients contaminate coral reefs when these products wash off while swimming or bathing. Reef-safe sunscreens are alternative sunscreens that provide effective sun protection while averting damage to coral reefs. The purpose of this research was to determine the dominant factors leading to the pro-environmental behavior of using reef-safe sunscreen and identify practices that Hawai‘i hotel operators could implement to influence patrons to engage in this behavior. This research applied an integrative conceptual framework to model pro-environmental …

Effects Of Ambient Air Pollution On Asthma-Related Emergency Department Visits Within The Las Vegas Metropolitan Area, Loiren E. Monardes

UNLV Theses, Dissertations, Professional Papers, and Capstones

The objective of this research was to evaluate the risk for asthma-related Emergency Department visits and their association with ambient air pollution within the Las Vegas metropolitan area. All data were aggregated by date and ZIP Code. The association was analyzed by applying the distributed lag non-linear model in an attempt to identify elevated concentrations of specific air pollutants

as triggers and their delayed effects (lag days). Relative Risk (RR) and 95% confidence intervals were produced, while adjusting for socioeconomic status. This ecological population-based study analyzed daily asthma counts of Emergency Department visits from January 1st, 2009 to December 31st, …

Examining Environmental Hazards In Rental Homes And Habitability Laws In Clark County, Nevada, Jorge Luis Bertran

UNLV Theses, Dissertations, Professional Papers, and Capstones

It is well established that home conditions are linked to the health outcomes of occupants. There are over 880,000 housing units in Clark County, Nevada; nearly half of those are renter-occupied units (ROUs). Currently, there is limited research on the characteristics of environmental hazards found in Clark County ROUs and the strength of habitability statutes created to protect tenants from substandard housing. Understanding how renters in Clark County are affected by environmental hazards in ROUs and the processes by which landlords and tenants resolve grievances related to those hazards would benefit public health. It would enhance the ability to quickly …

Prokaryotic Diversity And Aqueous Geochemistry Of Subsurface Environments Of The Death Valley Regional Flow System, Joshua David Sackett

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation summarizes over four years of effort towards the completion of a Ph.D. in Biological Sciences. The work presented in this document covers a broad range of topics, but a central unifying theme is prokaryotic life in the continental subsurface. The work presented in each chapter relied heavily on cultivation-independent methods for assessing prokaryotic communities, including prokaryotic community structure reconstruction from high-throughput sequencing of 16S rRNA gene libraries and single-cell genome analysis of novel uncultivated bacteria.

Chapter 2 examines the aqueous geochemistry and prokaryotic diversity of Devils Hole, a cavernous limnocrene and sole natural habitat for the critically endangered …

Triple Bottom Line As A Method To Increase Business Value And Foster Positive Social And Environmental Change, Jayleene West

Master's Theses

The Triple Bottom Line (TBL) business model has transformed the business world by changing the way businesses operate. By focusing on the people and the environment, businesses have grown to see substantial profit and avoid risks along the way. Companies are using the TBL to build their brand and customer loyalty by enhancing the environment and society. This paper analyzes four companies that are leaders in their industry and are founded on the TBL; Seventh Generation, New Belgium Brewing, Patagonia, and Ben & Jerry’s. Recommendations have been made by performing a literature review on the advantages and disadvantages of the …

As The Clothing Industry Is A Major Polluter, Sustainable Fashion Is Rising, Gabe Herman

Capstones

That the fashion industry is one of the biggest polluters in the world is one of the industry’s best-kept secrets — it uses a quarter of the chemicals produced globally, and its share of the world’s CO2 emissions is expected to rise from 2 percent to 26 percent in the next 30 years. Developing nations — where many factories are located — are most affected. Every year in Bangladesh, for example, tanneries dump enough toxic waste into rivers to fill three Olympic-sized swimming pools. Advocates and some in the fashion world are working to not only get the word out, …

Sustainably Managing Groundwater - Surface Water Interactions Within The Santa Rosa Plain Basin, Rhianna Frank

Master's Projects and Capstones

In this paper, I designed a strategy for implementation of sustainably managing groundwater-surface water interactions in the Santa Rosa Plain Basin in compliance with the requirements set forth by the Sustainable Groundwater Management Act of 2014. The research objectives for this analysis are: (1) to fully examine the requirements of the Sustainable Groundwater Management Act and the implications that implementation will have on the Santa Rosa Plain Basin, (2) to use technical data gathered regionally coupled with related policy design theory to analyze how groundwater and surface water interactions can be managed to meet the requirements set forth in this …

Development Of Exploratory Data Analysis Methods For Chemical, Spatial And Temporal Analysis Of Surface Water Quality Data: The Ontario Provincial Water Quality Monitoring Network, Shuyang Wang

Electronic Thesis and Dissertation Repository

Surface water quality (SWQ) databases have been widely compiled to provide information characterizing environmental conditions. But SWQ databases appear to be under-utilized, given the large investment in their creation. One reason is that database spatial, temporal, and compositional dimension vary through time, reflecting changing priorities through time and contrasts between different agencies, making coherent analysis challenging. This thesis explores the Ontario Provincial Water Quality Monitoring Network (PWQMN) to derive higher order hydrochemical properties, to render SWQ data in “network space” permitting catchment-wide visualization, and in undertaking temporal trend analysis.

Rivers play a critical role in the terrestrial carbon cycle, but …

An Evaluation Of Extended Producer Responsibility (Epr) As A Policy Option For Compostable Plastics In California, Amy Franz

Master's Projects and Capstones

This research project evaluates Extended Producer Responsibility (EPR) in California as a viable option to address the end-of-life management challenges identified for compostable plastics. The evaluation is done in three ways (1) review the main challenges identified for managing compostable plastics against the existing California EPR laws for mercury thermostats, agricultural pesticide containers, carpet, paint and mattresses to look for overlap in issues EPR has been used to address, (2) review compostable plastics in the context of the Product Selection Criteria used by California, (3) Look at the California Framework for setting up an EPR program to lay out what …

Potential Impacts Of The Purple Salt Marsh Crab, Sesarma Reticulatum, On Long Island Sound Salt Marshes, Jaymie Frederick

Master's Theses

Salt marshes are important, highly productive ecosystems that provide many ecological benefits, including shoreline protection. Salt marshes were long believed to be driven by bottom up forces, however, recent research has suggested that top down influences may impact the foundation species Spartina alterniflora, and consequently marsh structure. This study looked at patterns of Spartina alterniflora dieback along creek bank areas and assessed Sesarma reticulatum abundance spatially throughout the marsh to improve understanding as to whether Sesarma may be influencing the dieback phenomenon. Dieback was occurring in all three salt marshes studied, at two of those marsh sites the rate of …

Lone Wolves And Copycats: Assessing Policy And Infrastructure For Flood Hazard And Floodplain Management, Samantha L. Hamlin

Dissertations and Theses

To mitigate flood hazard, which affects millions of people every year, increasing numbers of communities are developing green infrastructure policies to not only mitigate the hazard, but to meet other community policy objectives, as green infrastructure is often cited for the multiple benefits it confers. To support the implementation of policies that help communities meet their policy objectives, however, it is imperative to understand how policy is innovated and adopted. To do so, I applied the internal determinants and regional diffusion models, what I refer to as the lone wolf and copycat models. In policy, a lone wolf innovates a …

Water Conservation Practices For Irrigation Of Turfgrass Lawns, Daniel Sandor

Graduate Theses and Dissertations

Turfgrass lawns are widely used in residential and commercial landscapes, providing many environmental, aesthetic, and recreational benefits. However, concerns and scrutiny arise with perceived maintenance requirements, particularly with regards to irrigation. It is important to manage irrigation in order to maximize water conservation without significantly reducing lawn quality. A series of field and greenhouse studies were conducted to investigate how water usage might be reduced in irrigation practices with the following proposed objectives: 1) evaluate the use of rain and soil moisture sensors in a humid transition zone environment; 2) evaluate the effects of chronic drought stress between drought-resistant and …

Assessing Biofiltration Without Ozonation For Removal Of Trihalomethane Precursors In Drinking Water At The Beaver Water District Drinking Water Treatment Plant, Sana Ajaz

Graduate Theses and Dissertations

Biofiltration without pre-ozonation has the capability to remove natural organic matter (NOM) fractions that serve as precursors of disinfection byproducts (DBPs), which include the four regulated trihalomethanes (THMs) and dichloroacetonitrile (DCAN). Rapid small-scale column tests (RSSCTs) and Pilot Plant filters operated at empty-bed contact times (EBCTs) of 4, 8, and 16 minutes were used to evaluate the performance of nutrient-amended (free ammonia and phosphorus) biofiltration for THM and DCAN precursor removal, as measured using formation potential (FP) tests. NOM surrogates – which include dissolved organic carbon (DOC), specific ultraviolet absorbance (SUVA254) and fluorescence-PARAFAC components – were measured weekly throughout the …

The Built Landscape And Ecological Behavior: Patterns For Readdressing Environmental Thinking In Residence Hall Design, Sarah Keogh

Theses and Dissertations

This research addresses how architectural design processes and practices are implicated and/or reflected in social constructions of ecological thinking. It is generally recognized that human behaviors are affecting climate change and giving rise to a plethora of ecological issues; yet a transformation of widespread behavior has not yet followed. This raises questions. In the field of architecture, how can the built landscape function to encourage and support sustainable behavior patterns?

Looking at universities as locations that are embedded in their urban contexts and have influence both on their surrounding communities and on year after year of students who pass through, …

Assessment Of Drinking Water/Aquifer Vulnerability To Contamination By Natural Manganese And Anthropogenic Chemicals In The U.S., Ryan Kelly

International Development, Community and Environment (IDCE)

Aquifers in the U.S. store groundwater used by many Americans every day for drinking eating, bathing and cleaning. These underground sources of water are vital to life and may be subject to contamination from both natural and anthropogenic pollution, including manganese (Mn) – especially shallow aquifers (<100 feet to bedrock). Natural sources of Mn are found in soils, surficial deposits, and bedrock, while anthropogenic contamination derives from landfills, waste facilities, or industries that use toxic materials. Pollutants like Mn raise concern because there is no policy in place to enforce regulation of Mn levels in water supplies based on limited information about health effects. Yet studies have shown elevated levels of Mn intake can lead to adverse human health effects. This study uses ArcMap to identify potential sources of Mn and/or toxics contamination in shallow U.S. aquifers based on geologic characteristics of a given aquifer source and proximity to waste sites. The results show approximately 2 million Americans may be at risk of consuming water with natural Mn contamination, and of those 2 million, close to 1.7 million are also vulnerable to additional toxics from anthropogenic waste. …

Assessment Of Soil Properties And Vegetation In A Mounded Native Tallgrass Prairie With An Aquic And Udic Soil Moisture Regime In The Ozark Highlands Region Of Northwest Arkansas, Tyler Joseph Durre

Graduate Theses and Dissertations

Native tallgrass prairies were once considered to be the dominant pre-settlement vegetation type in the eastern third of the Great Plains, but are now designated as America’s most endangered ecosystem due to conversion to agricultural land. Prairie mounds are unique soil features still present in remnant native tallgrass prairies across the United States. The main objective was to determine the effects of soil moisture regime (i.e., aquic and udic), mound position, (i.e., mound summit, backslope, toeslope, inter-mound), soil depth (i.e., 10-cm intervals from 0 to 90 cm), and their interactions on soil physical, chemical, and hydraulic properties in a mounded …

Effect Of Macrograzers (Campostoma Spp. And Faxonius Spp.) On Periphyton In Ozark Streams With Considerations Given To Macrograzer Biomass, Phosphorus, And Season: Mensurative And Manipulative Studies, Kayla R. Sayre

Graduate Theses and Dissertations

Nutrient and benthic algal biomass relationships can guide numeric nutrient criteria development in lotic systems. However, herbivorous macrograzers may confound this relationship by reducing the slope of the positive relationship between nutrients and periphyton biomass in streams. I conducted a mensurative field study to determine if stoneroller and crayfish abundance related to algal biomass at varying nutrient concentrations and manipulated macrograzer presence with electrical exclosures in streams to examine macrograzer effects on algal biomass and understand whether these effects on periphyton varied with total phosphorus (TP) or season. Macrograzer density was quantified across a TP gradient (n=15 streams; range = …