Digital Commons Network^™

Reduction In Salt Deposition On Carbon Nano-Tube Immobilized Membrane During Desalination Via Membrane Distillation, Madihah Saud Humoud

Dissertations

As water scarcity increases globally under the stresses of increasing demand, aquifer depletion, and climate change, the market for efficient desalination technologies has grown rapidly to fill the void. One such developing technology, membrane distillation (MD), has found much interest in the scientific community. MD has also been powered by solar energy and waste heat resources because it can be operated at relatively low temperatures. Recent studies indicate that MD could potentially achieve the efficiencies of state-of-the-art mature thermal desalination technologies, although additional engineering and scientific challenges must first be overcome.

MD can be used to treat high salinity water …

Dental Professionals Occupational Noise Exposure And Its Auditory And Non-Auditory Effects, Alexis Frees

Theses

The purpose of this study was to assess noise exposure and its auditory and non-auditory effects on workers in five clinical departments in the School of Dental Medicine at Rutgers Biomedical Health Sciences Campus in Newark, New Jersey. The study included environmental noise level measurement, dental instrument sound level measurement, personal noise dosimetry and a questionnaire survey to assess non-auditory effects. Octave band analysis of environmental noise levels showed that they are slightly above the standard noise criteria for clinics, and measurements from six dental instruments confirm that they contribute higher sound pressure levels at the frequencies of 1000, 2000, …

Evaluation Of The Mechanisms And Effectiveness Of Nano-Hydroxides, Wood And Dairy Manure-Derived Biochars To Remove Fluoride And Heavy Metals From Water, Anna Rose Wallace, Wenjie Sun Dr, Chunming Su Dr

Civil and Environmental Engineering Theses and Dissertations

The development of effective treatment processes for the removal contaminants, such as fluoride and heavy metals, from polluted water have been urgently needed due to serious environmental health and safety concerns. In this dissertation, a variety of materials including various (hydro)oxide nanomaterials, biochars and surface modified biochar were studied to evaluate their effectiveness and mechanism on removing fluoride or mixed heavy metals from water.

In the Chapter 2, this study investigated the adsorptive removal of fluoride from water using various (hydro)oxide nanomaterials, focusing on ferrihydrite, hydroxyapatite (HAP) and brucite, which have the potential to be used as sorbents for surface …

A Study Of Chloride Levels In Pine Creek, Allegheny County, Pa, Selina Prettner

Electronic Theses and Dissertations

Pine Creek is a 22.8-mile long tributary to the Allegheny River draining over 67 square miles of northern Allegheny County, PA. The main stem runs along Route 8 and receives extensive runoff from road salt from deicing. A site near Etna, PA sampled biweekly in 2013 consistently showed elevated conductivity that correlated with increased chloride levels. Winter road deicing runoff produced acute chloride concentrations up to 678 mg/L. Chloride fluctuated in the summer and autumn months but did not exceed the USEPA Secondary Drinking Water Standard (250 mg/L) or the aquatic life criterion for chronic concentrations (230 mg/L). Sampling throughout …

The Vezo Communities And Fisheries Of The Coral Reef Ecosystem In The Bay Of Ranobe, Madagascar, Shane Abeare

University of New Orleans Theses and Dissertations

Madagascar, a country whose extraordinary levels of endemism and biodiversity are celebrated globally by scientists and laymen alike, yet historically has received surprisingly little research attention, is the setting of the present dissertation. Here, I contribute to the need for applied research by: 1) focusing on the most intensely fished section of the Toliara Barrier Reef, the Bay of Ranobe; 2) characterizing the marine environment, the human population, and the fisheries; and 3) collecting the longest known time-series of data on fisheries of Madagascar, thereby providing a useful baseline for future analyses. In Chapter 1, the bathymetry of the Bay …

Student Sustainability Leadership Development At Portland State University: Developing Holistic Sustainability Leaders, Megan Suzanne Schneider

Dissertations and Theses

In order to address the myriad of social, economic, and environmental challenges the world is facing, we need to be able to engage in leadership that fosters collective action towards sustainable solutions. Higher education is an institution that can equip people with the abilities to engage in sustainability leadership. This master's thesis research explores how students develop sustainability leadership through their college experience. Nine students, who had been identified as sustainability leaders through their participation in the Student Sustainability Center (SSC), a co-curricular sustainability program at Portland State University, were selected to be part of this grounded theory research project. …

A Landscape On The Threshold Of Change: Patterns Of Soil Microbial Ecology Along Dynamic Geomorphic And Hydrologic Features In A Polar Desert, Kelli L. Feeser, David J. Van Horn, Heather N. Buelow, Daniel R. Colman, Theresa A. Mchugh, Jordan G. Okie, Egbert Schwartz, Cristina D. Takacs-Vesbach, Becky A. Ball, Andrew G. Fountain, Michael N. Gooseff, Joseph S. Levy, Maciej K. Obryk

Biology ETDs

The McMurdo Dry Valleys (MDV) of Antarctica are on the threshold of widespread landscape scale change due to increasing temperature and solar radiation and altered hydrology: buried ice is melting, the soil active layer is thickening, thermokarst features are developing along streams, water tracks are expanding, and lake levels are rising. These changes will impact the microbial communities found in each of the affected habitats. The purpose of this work is to first, understand the spatial distribution of soil bacteria in the MDV, specifically investigating the scale-dependent effects of environmental heterogeneity, and second, to perform surveys and coupled experiments to …

Flood Dynamics In The Portland Metropolitan Area, Past, Present, And Future, Lumas Terence Helaire

Dissertations and Theses

The Portland area has an extensive flood history since it was founded in 1845. In the late 19th century, the Portland area was prone to flooding from snowmelt freshets (3-6 months duration) and brief winter rain or rain-on-snow events. Since that time the magnitude of spring freshets has been curtailed by 45% due to climate change, flow diversions, and reservoir management. Along with changes in hydrology, the bathymetry of the Lower Columbia River has been altered by the dredging of the navigation channel, diking, and land reclamation. To understand how these changes in hydrology and bathymetry have affected tidal and …

On The Frontlines - The Fishermen Of Ibrahim Hyderi, Muhammad Haris Aslam Khan

MSJ Capstone Projects

Climate change has become a matter of recent debate for much of the world. According to a report published by a German watch, a non-governmental organization, in 2019, Pakistan among the five countries at severe risk of climate change disasters.

During the last two decades, Pakistan saw more than 141 extreme climatic catastrophes. Only in 2016, more than 566 people died due to these conditions.

A report published by Asian Development Bank in 2017 indicates Pakistan’s climate change profile. It states that more than 1,600 people have lost their lives in the super flood of 2010 alone. A loss of …

Mojave Desert Ecosystem Recovery: Potency Of Biotic And Abiotic Restoration Methods In Low Elevation Plant Communities, Mary Amanda Balogh

UNLV Theses, Dissertations, Professional Papers, and Capstones

The historic and current state of land in the Mojave Desert, including land managed by the National Park Service with fundamental goals of natural resource conservation and preservation, been severely degraded by a variety of anthropogenic disturbances. Due to increasingly sporadic and unpredictable precipitation patterns, land managers struggle to implement restoration projects with high success rates and are resource-limited for post-treatment monitoring. In this study, I examined success rates of biotic (outplanting, seeding) and abiotic (soil manipulation, vertical mulch) restoration treatments on various disturbance types in the creosote-bursage (Larrea tridentata-Ambrosia dumosa), blackbrush (Coleogyne ramosissima), and Joshua tree woodland (Yucca brevifolia) …

On Muddy Banks: An Ecoethnography Of A River Island Community, Nicholas Baxter

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this study, I examine the relationship between a river and a community. Specifically, I analyze the processes and patterns that organize the nature-society relationship and define the river town of Sabula, IA. To guide my historical and ethnographic analysis, I utilize a co constructionist posture (Rice 2013), which sees culture, community, economy, and physicality as much a product of bio-physical forces as social forces. My aim is to understand how Sabula is conjointly constructed and reveal the nuanced interconnections between human communities and nature through which social and environmental problems play out. My analysis clarifies patterns in residents’ identity …

Landscape Scale: Inter- And Intraspecific Variation In Plant Interactions Along A Stress Gradient In The Sheep Range Of Nevada, Jordan Dowell

UNLV Theses, Dissertations, Professional Papers, and Capstones

Impending threats to shrubland ecosystems, posed by climate change, necessitate niche modeling efforts to project vegetation range shifts. However, efforts often remain unguided by individual-scale interspecific plant interactions. The stress gradient hypothesis posits that facilitation should increase in areas of high abiotic stress, only if the individuals are able to ameliorate the surrounding area via functional traits. The Sheep Range of Nevada was used to assess the role of functional traits as predictors of plant association. Larrea tridentata, Coleogyne ramosissima, and Artemisia nova were selected as shrubs with variable life history strategies and ranges in order to identify general patterns …

Mojave Desert Plant Community Long-Term Response To Disturbance, Dominic M. Gentilcore

UNLV Theses, Dissertations, Professional Papers, and Capstones

All vegetation communities have been shaped by disturbances. This dissertation consists of three separate chapters: Blackbrush (Coleogyne ramosissima) natural regeneration in the Great Basin-Mojave Desert Transition Zone on two fires, Long-term Response to Fire in Eastern Mojave Desert semi-arid shrubland communities, and an Annotated Checklist of Gold Butte National Monument in the Mojave-Colorado Plateau Transition Zone. The section on blackbrush natural regeneration was a long-term dataset from two fires in Basin and Range National Monument that burned in 2008 with monitoring events in 2009, 2010, 2011, 2018 and 2019. The monitoring documented some of the strongest post-fire regeneration for the …

Utility Of Bench Scale Sand Tank Experiments At Assessing Permeable Reactive Barrier Design, Brandon Meier

UNLV Theses, Dissertations, Professional Papers, and Capstones

The objective of this work was to evaluate the utility of bench scale sand tank experiments at assessing permeable reactive barrier (PRB) design. Our criteria for meeting this goal was that differences between PRB designs could be identified solely by measuring concentration in outflow from the sand tank models. For our PRB designs (funnel-and-gate, staggered wells, and parallel bars), numerical simulations clearly showed that PRB design had a quantifiable effect on outflow concentration, provided that the solute reacted with the PRB materials. Conversely, use of a conservative (non-reactive) solute did not allow us to discern between PRB design alternatives. Employing …

Carbon Management And Volatile Fatty Acid Production In Primary Clarifiers At A Wastewater Treatment Plant, Brittany Nicole Radke

UNLV Theses, Dissertations, Professional Papers, and Capstones

An increasing number of treatment plants are required to remove nutrients from domestic wastewater to lessen the impact of nutrient loading to water bodies. Enhanced Biological Phosphorus Removal (EBPR) is one of the processes commonly used to remove phosphorus from domestic wastewater. The presence of an adequate quantity of volatile fatty acids (VFA) in the wastewater influent to EBPR is important for process efficiency and stability. The objective of this research was to investigate the production of VFAs through fermentation of sludge in primary clarifiers as it related to improving nutrient removal, primarily targeting phosphorus.

The research tested, in full-scale, …

Application Of Data-Driven And Process-Based Modeling Approaches For Water Quality Simulation In Lakes And Freshwater Reservoirs, Ali Saber Sichani

UNLV Theses, Dissertations, Professional Papers, and Capstones

Lakes and freshwater reservoirs often serve as the primary drinking and irrigation water sources for surrounding communities. They provide recreational and tourism opportunities, thereby promoting the prosperity of neighboring communities. Reliable estimates of water quality in lakes and reservoirs can improve management practices to protect water resources.

Seasonal water temperature and solar shortwave radiation variations, and their subsequent interactions with water column aquatic life, combined with seasonal variations of mixing intensity throughout the water column, result in variations of water quality constituents with depth during the annual cycle. The complexity of these variations entails the use of advanced water quality …

The Retrospective Analysis Of Radionuclides In Banded Coral From The Bikini Atoll, Athena Marie Gallardo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Nuclear weapons testing conducted within the Bikini Atoll in the Marshall Islands resulted in local fallout contamination, including long lived isotopes of plutonium (Pu) and uranium (U), within the surrounding environment. The Bikini lagoon provides a continuous source of Pu (239+240Pu) and U (236U) to the Pacific Basin. The rate at which these isotopes are flushed from the lagoon to the ocean is balanced by inputs from remobilization of lagoon sediments. This research will provide a basis for predicting future change in the solubility and export potential of Pu and U in lagoon sediments. This is important to better understand …

The Workability Of Dominican University Of California (Duoc) Transitioning To A Community Choice Aggregation (Cca) Program Energy Supply, Alexandra Fuentes

Master's Theses

For almost 10 years Community Choice Aggregation (CCA), or community based energy programs, have been developing and or providing clean energy resources to both commercial and residential customers in various regions around the United States. Although there are several programs in communities in the surrounding regions of California, this study focuses on a specific California program known as MCE. This research examines the feasibility of Dominican University of California (DUoC) transitioning from Pacific Gas and Electric (PG&E) to becoming a client of MCE in the future. Out of the 19 community energy programs currently available in the state, MCE is …

The Rockaway Project - Townes, Diara Jepris D. Townes

Capstones

The Rockaway Project is a story-driven website that provides information on the government response to Superstorm Sandy recovery on the Rockaway peninsula in Queens, New York. Dozens of climate resiliency projects have been delayed or remain unfinished, despite millions of dollars in funding and six years of promises. The website hosts audio, visual and digital content, gathered through interviews and data collection.

Link to capstone project: https://www.youtube.com/watch?v=fAq2BeR4bS0&t=1s

Pre-Juvenile Naked Goby (Gobiosoma Bosc) Age And Growth, Annamaria Deitz, Juliana Harding

Honors Theses

Due to the abundance of larval naked gobies, Gobiosoma bosc, within the estuarine ichthyoplankton, it is important to understand their age and growth. Naked gobies are a largely distributed, both geographically and within an estuary, small, benthic fish species. There are 3 pairs of otoliths, calcium carbonate structures within the ear canal, that detect vibrations and record the age of the fish, both daily and annually. Using laboratory-reared gobies of a known age (Tremont et al. 2015), daily signatures on the sagittal otoliths were first validated to be daily, then a growth curve for the wild caught larvae was …

California Stream Condition Index (Csci) Score Analysis Of Streams Sampled From 1998 To 2017 In The San Francisco Bay Region, Jenna Rais

Master's Projects and Capstones

Human impacts to California’s streams have altered the state’s riparian and hydrological landscape. This is a critical issue with regard to natural resources, including ecosystem services such as water availability and water quality. Regulations have a limited amount of impact on the improvement of this landscape and can also become complicated by politics. Scientific advances have developed ways to quantify and describe the quality of streams, this includes the development of the California Stream Condition Index (CSCI) which is based on benthic macroinvertebrate (BMI) population numbers and functions. This index allows scientists to not only score the quality of a …

Northern Conifer Forest Management: Silvicultural, Economic, And Ecological Outcomes From 65 Years Of Study, Maren Granstrom

Electronic Theses and Dissertations

While forest managers once sought primarily to produce sustainable revenue from harvests, there is now growing value placed on non-timber outcomes like wildlife habitat, climate adaptability, and carbon storage. When deciding how to manage land for the future, foresters and landowners must assess the many outcomes of forestry activities and be aware of the tradeoffs inherent to achieving different goals. Given the slow growth of trees relative to other commercial crops, it is rare to have the continuity of land ownership, researchers, and funding needed to follow a stand for a full rotation or to observe a tree from recruitment …

A Survey Of Single-Use Plastic Foodware Ordinances Of The San Francisco Bay Region, Christopher Slafter

Master's Projects and Capstones

Municipal jurisdictions in the San Francisco Bay Region (SFBR) are passing comprehensive single-use plastic (SUP) foodware ordinances in response to growing public pressure, and a California mandate to achieve zero waste. SUP foodware items have become an issue of concern because they are readily available in the restaurant industry, and are regularly among the top-ten pollutants collected during beach cleanups. SUP foodware items pose a danger to marine wildlife and contribute to rising carbon dioxide (CO₂) emissions. Policy makers in the SFBR are creating local ordinances that regulate the distribution and use of a variety of SUP foodware …

Rain Gardens: The Return Of Ecosystem Services, Katie Dehaan

Honors Theses

In the modern world impervious surfaces, especially in urban areas, abound. These include roads, highways, sidewalks, parking lots, and roofs that have replaced permeable surfaces, mainly open land, forests, and wetlands. Rainwater runs off of these surfaces collecting pollutants on its way to permeable areas. Rain gardens collect and process rainwater. Native plants with deep root systems process large volumes of rainwater and the microorganisms living in the soils and roots can process pollutants. The purpose of my research was to find out what variables affect species presence or absence in rain gardens. Species presence or absence at the time …

Air Quality And Environmental Justice: An Analysis Of County-Level Data In The United States, Alyssa Tittle

Honors Theses

This paper analyzes the relationship between air pollution and poverty and race/ethnicity at the county level in the United States. Using air pollution data from the Environmental Protection Agency and population characteristics data from the Census Bureau to model relationships in RStudio, results show that race/ethnicity, population, and median value of owner-occupied housing units are the most statistically significant variables associated with air quality.

Economic And Strategic Analysis Of America's Wastewater, Jorden Hansen

Theses/Capstones/Creative Projects

Whether it be tap water from a home or bottled water from a grocery store, clean water is generally accessible in the United States. Unfortunately, this convenience deters people from learning about the complex processes that make this luxury possible.

Awareness of the natural water cycle is widespread, as the simplest version is taught in grade school. It illustrates the flow of water as it changes state (liquid, to solid, to gas) in the environment. Not so commonly known is the urban water cycle which manifests residential daily use with the revolution of water. The urban water cycle is a …

Estimation Of Evapotranspiration And Other Water Budget Factors At Glacier Creek Preserve, Kian Paul Mcintosh

Theses/Capstones/Creative Projects

A water budget of a watershed consists of the inputs and outputs of water to and from it, including precipitation, change in water storage, surface water flow, and evapotranspiration. Water budget estimates are of high importance as a result of increasing demand due to population growth and other factors. Improving estimate accuracy and precision of evapotranspiration and runoff to streams allows scientists to better determine the true availability of water for human and conservation use. At Glacier Creek Preserve, 6.5% of the incoming precipitation left the preserve as discharge from the stream and 95.9% of the incoming precipitation was lost …

The Effects Of Climate On Suicide Rates In 36 Oregon Counties, Elshadai Hailu, Maria Hernandez

Student Scholarship - College of Business

This study looked at average temperature, amount of rainfall and amount of sunshine in all 36 Oregon counties and how they affect suicide rates. Climate information was gathered over the past 30 years and suicide rates were measured between the years 2013 and 2016. It was hypothesized that there would be a negative relationship between low temperature and suicide rates. It was also predicted that there would be a negative relationship between high temperatures and suicide rates. This study found that there was a negative relationship between average high temperature and sucide rates. It also found there is to be …

Two Fields, One Pellet: Combining Demographics And Population Genetics Through Non-Invasive Sampling Of Snowshoe Hare Fecal Pellets In Michigan., Genelle Nicole Uhrig

Theses and Dissertations

As climate continues to change at a rapid rate, species are increasingly vulnerable to the resulting environmental changes. This is especially true for species whose fitness is closely linked to climate-associated environmental conditions. One of these vulnerable species is snowshoe hare, Lepus americanus, who depends on the timing and duration of snowfall to provide camouflage when they go through seasonal pelage changes from brown in the summer to white in the winter. Whereas snowshoe hare are stable across the core of their range, populations along the southern range edge are experiencing declines due to climate driven environmental changes that cause …

A Transfer Students Guide To Becoming A Pca, Zack J. Krueger

Agricultural Education and Communication

A transfer students guide to becoming a PCA through the AGED department as opposed to AEPS. Agricultural science majors. Classes shown and listed cooperate with the California Department of Pesticide Regulations required course list necessary to take the Pest Control Advisers exam.