Digital Commons Network^™

An Application Of M-Matrices To Preserve Bounded Positive Solutions To The Evolution Equations Of Biofilm Models, Richard S. Landry Jr.

University of New Orleans Theses and Dissertations

In this work, we design a linear, two step implicit finite difference method to approximate the solutions of a biological system that describes the interaction between a microbial colony and a surrounding substrate. Three separate models are analyzed, all of which can be described as systems of partial differential equations (PDE)s with nonlinear diffusion and reaction, where the biological colony grows and decays based on the substrate bioavailability. The systems under investigation are all complex models describing the dynamics of biological films. In view of the difficulties to calculate analytical solutions of the models, we design here a numerical technique …

Automated Species Classification Methods For Passive Acoustic Monitoring Of Beaked Whales, John Lebien

University of New Orleans Theses and Dissertations

The Littoral Acoustic Demonstration Center has collected passive acoustic monitoring data in the northern Gulf of Mexico since 2001. Recordings were made in 2007 near the Deepwater Horizon oil spill that provide a baseline for an extensive study of regional marine mammal populations in response to the disaster. Animal density estimates can be derived from detections of echolocation signals in the acoustic data. Beaked whales are of particular interest as they remain one of the least understood groups of marine mammals, and relatively few abundance estimates exist. Efficient methods for classifying detected echolocation transients are essential for mining long-term passive …

Assessment Of Vegetation Response To Wildfire At Bandelier National Monument, New Mexico: Case Study Of The Las Conchas Fire, Gladys Valentin-Gonzalez

Geography ETDs

In the past couple of decades, there has been an increase in the occurrence of wildfire events in the United States. The U.S. Forest Service estimates that over 73,000 wildfires on average occur annually in the U.S., burning about 7.3 million acres of land. Bandelier National Monument, in northern New Mexico, has been affected by several wildfires in the past 40 years, one of the most recent being the Las Conchas Fire in 2011, which burned over 60,700 hectaresin Bandelier National Monument and Valles Caldera National Preserve. This research explores a remote-sensing based assessment of vegetation response to and recovery …

A Little Known Trade Deal Could Soon Derail America's Booming Solar Industry, Sam Donnenberg

Capstones

A trade deal has been winding its way through hearings at the International Trade Commission for months that could have major consequences for America's solar energy industry. Two solar energy companies are requesting that tariffs be applied to Chinese solar product imports. But industry analysts say this will cause the price of solar to rise and harm the industry during a period of unprecedented growth. The petition has only one stop left on its way to approval: The desk of President Trump.

https://www.alanapipe.com/sam-donnenberg/sam-donnenberg-index.html

Username: sam-donnenberg

Password: capstone

Rethinking Holocene Ecological Relationships Among Caribou, Muskoxen, And Human Hunters On Banks Island, Nwt, Canada: A Stable Isotope Approach, Jordon S. Munizzi

Electronic Thesis and Dissertation Repository

This dissertation explores the ecology of caribou (Rangifer tarandus spp.) and muskoxen (Ovibos moschatus), and its relevance to human hunters on Banks Island, NWT, Canada, over the last 4000 years, primarily through the isotopic analysis of modern and archaeological faunal remains.

First, we establish baseline carbon and nitrogen isotope relationships between modern vegetation and caribou and muskox bone collagen using Bayesian mixing models. The models indicate that dwarf shrub (Salix arctica) does not contribute significantly to bone collagen isotopic compositions in either species, while sedges and yellow lichen (Cetraria tilesii) do. These findings …

Hazmat Storage Near Nyc Waterways Endangers Communities, Brett E. Dahlberg, Nicole Acevedo

Capstones

New York City has 520 miles of shoreline--that’s more than Miami and Los Angeles combined. These waterfronts are home to some of the city’s most polluted sites because major part of it is zoned for industrial use. Dozens of industrial plants in this area store toxic chemicals in flood zones: substances that are hazardous to our health, like Benzene, which is used in rocket fuel, toluene, a paint thinner, and lead a neurotoxin. In a flood, these chemicals can easily get caught up in moving waters and pollute entire neighborhoods.

That’s exactly what happened when Hurricane Sandy hit in 2012. …

Seasonal Resource Selection And Habitat Treatment Use By A Fringe Population Of Greater Sage-Grouse, Rhett Boswell

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Movement and habitat selection by Greater Sage-grouse (Centrocercus uropasianus) is of great interest to wildlife managers tasked with applying conservation measures for this iconic western species. Current technology has created small and lightweight GPS (Global Positioning Systems) transmitters that can be attached to sage-grouse. Using GIS software and statistical programs such as Program R, land managers can analyze GPS location data to assess how sage-grouse are geospatially interacting with their habitats. Within the Panguitch Sage-Grouse Management Area (SGMA) thousands of acres of land have been restored or manipulated to enhance sage-grouse habitat; this usually involves removal of pinyon pine …

Evaluating Potential For Water Quality Decline In Maine Lakes, Kaci N. Fitzgibbon

Electronic Theses and Dissertations

Understanding lake vulnerability with respect to eutrophication and loss of water quality is important for sustainability of aquatic ecosystems. This project aims at identifying and quantifying the effects of relevant physiochemical, climate, and watershed characteristics on lake vulnerability in order to develop management decision tools for the Maine Department of Environmental Protection (MEDEP). In a changing chemical and physical environment, using independent variables from each of these categories and then relating them to the summer lake epilimnetic phosphorus (P) concentrations allows for development of models to inform stakeholders of lake vulnerability to eutrophication problems.

We studied 24 lakes covering a …

Remediation Strategies For Mercury Contaminated Lakes And Reservoirs Within The State Of California, Emily Chortek

Master's Projects and Capstones

Mercury is an environmental and public health concern due to its neurodegenerative effects and ubiquitous concentration within the environment. To mitigate these risks and reduce concentrations within the environment, remediation methods are necessary. The purpose of this paper is to investigate and evaluate the efficacy of a number of remediation options for mercury contaminated lakes and reservoirs in the State of California. This paper also identifies a number of challenges associated with the implementation of each method and provides recommendations for environmental managers to use when remediating mercury contaminated lakes. Hypolimnetic oxygenation (HOS) was found to be the least problematic …

Environmental Ngo-Private Sector Partnerships: A Tool To Generate Business Value And Protect The Natural World, Carolyn Nogy Nogy

Master's Projects and Capstones

Many environmental challenges are complicated by complex and social, cultural, economic and political interactions, which are difficult to address by a single entity. However, partnerships can offer the necessary depth and versatility to address them effectively. By working together, there is an opportunity for cross sector partners to leverage their unique expertise, while blending resources to achieve more comprehensive and sustainable solutions to existing environmental problems. This project examines the use of partnerships between environmental NGOs and the private sector to manage complex environmental problems, providing a critical assessment of the partnership attributes that generate the most mutual benefit. The …

Planning Cities, Economically Or Communally: A Comparative Study Of Amsterdam And San Francisco, Raina Dawn Whittekiend

Master's Theses

Globalization has spun “community” off its axis. What once defined community is no longer the current state of the community. Increased economic transactions have led to the instability of communities that once depended on one another at the local level. These communities are now dependent on systems that do not know nor understand their actors. This lack of relationship between development and subject is witnessed and highly scrutinized in developing countries all over the world and has been intensely researched in academic literature. This thesis intends to better understand why in modernized global cities these same processes of development and …

Abiotic- And Biotic-Formation Of Manganese Oxides And Their Fate In Environmental Systems, Haesung Jung

McKelvey School of Engineering Theses & Dissertations

Manganese (hydr)oxide (Mn (hydr)oxide) minerals are ubiquitous in aquatic and terrestrial environments. These minerals have high surface areas and are highly sorptive and redox active. From decades of accumulated knowledge about natural redox cycling, we have found that Mn (hydr)oxides play critical roles as electron donors and acceptors in elemental geochemical cycling and biological metabolisms in nature. Thus, Mn (hydr)oxides have garnered increasing interest to understand natural systems. Considering the variety of redox reactions with Mn (hydr)oxides in nature, it is also expected that there should be diverse pathways to form Mn (hydr)oxides through abiotic and biotic processes. Previous studies …

Fabrication And Modification Of Titania Nanotube Arrays For Harvesting Solar Energy And Drug Delivery Applications, Ahmed El Ruby Abdel Rahman Mohamed

Electronic Thesis and Dissertation Repository

The fast diminishing of fossil fuels in the near future, as well as the global warming caused by increasing greenhouse gases have motivated the urgent quest to develop advanced materials as cost-effective photoanodes for solar light harvesting and many other photocatalytic applications. Recently, titania nanotube arrays (TNTAs) fabricated by anodization process has attracted great interest due to their excellent properties such as: high surface area, vertically oriented, highly organized, one-dimensional, nanotubular structure, photoactivity, chemical stability and biocompatibility. This unique combination of excellent properties makes TNTAs an excellent photoanode for solar light harvesting. However, the relatively wide band gap energy of …

Biodiversity Of Larval And Adult Dragonflies And Damselflies (Odonata) Of Interdunal Wetlands At Saugatuck Harbor Natural Area, Devon Volz

Honors Theses

The effects of climate change on insects in the United States have yet to be fully understood. Research on the insect populations of Lake Michigan’s interdunal wetlands has been particularly limited. As these vibrant habitats are already at risk of destruction due to increased development, it is vital to have a working knowledge of the species that are living in the habitat. However, to date, there have been no studies on assemblages of interdunal wetlands in Michigan. Examining community compositions is critical to understanding the ecological problems that could occur in the future. This study is the first to look …

Non-Native Mangroves (Rhizophora Mangle) Of Moloka'i, Hawai'i: A Socio-Ecological Analysis, Casey Lynette Lewis

Dissertations and Theses

The formation of novel ecosystems by non-native species poses management challenges that are both socially and ecologically complex. This complexity necessitates consideration of both ecological dynamics and social attitudes and perceptions. Red mangrove propagules were introduced to Moloka'i, Hawaii in 1902 to mitigate the effects of soil erosion and they have since spread along the coast and to adjacent islands creating novel habitat. Non-native mangroves in Hawai'i present a unique case study to examine diverse social attitudes and perceptions resulting from a long history of land cover transformations on the Hawaiian Islands, socio-cultural diversity of involved stakeholders, and the potential …

Development Of High-Performing Polydimethylsiloxane-Based Membranes For Carbon Dioxide Separation, Tao Hong

Doctoral Dissertations

Membrane separation is highlighted as one of the most promising approaches to mitigate the excessive CO₂ [carbon dioxide] emission, due to its significant reduction of energy cost compared with many conventional separation techniques. Unfortunately, the separation performance of current membranes does not meet the practical CO₂/N₂ [nitrogen] separation requirements. And due to the huge volume of industrial flue gas, membranes with exceptionally high permeability are needed for practical reasons.

Currently, the separation mechanism of most polymeric membranes is based on size-sieving. However, this method is not sufficient for CO₂/N₂ separations due to the …

Impact Of Soil Water Content On Bermudagrass Athletic Field Performance, Kyley Hampton Dickson

Doctoral Dissertations

Soil water content (SWC) influences the consistency and performance of athletic fields. Two studies were conducted at the University of Tennessee Center for Athletic Field Safety (Knoxville, TN) to determine SWC impact on the performance of hybrid bermudagrass [Cynodon dactylon (L.) Pers. x C. transvaalensis, Burtt-Davy, ‘Tifway’] on silt loam (cohesive) and sand root zone conforming to United States Golf Association (USGA) specifications (noncohesive) root zones. Soil water content treatments for the cohesive soil averaged 0.10 m³/m³ (+/- 0.035), 0.17 m³/m³ (+/- 0.035), 0.26 m³/m³ (+/- 0.035), and 0.35 …

Memory Response: Exposure History Dependence Of Microbial Mediated Transformations Of Substrates In Groundwater, Charles Joseph Paradis

Doctoral Dissertations

The flow, transport, and reactivity of dissolved-phase constituents in an unconfined and shallow aquifer were characterized, in situ, by utilizing the single-well push-pull test method. In the first study, the re-oxidation/mobility of uranium, in the presence of nitrate oxidant, was shown to be mitigated by preferential oxidation/mobilization of solid-phase, reduced, sulfur-bearing species. These results indicated that establishing conditions conducive to uranium reduction and the formation of reduced sulfur-bearing species can increase the efficacy of sustained uranium reduction/immobility in the presence of re-mobilizing oxidants. In the second study, the analytical solution to describe the one-dimensional displacement of the center of …

Evaluation Of Water Resources And Hydraulic Influences In The Restoration Of The Western Part Of The Mesopotamian Marshlands, Ali Kareem Al-Quraishi

Graduate Theses and Dissertations

The purpose of this study is to assess the water resources and water conveyance system of the western part of the Mesopotamian marshes (Al-Hammar marsh) as well as develop a water conveyance system to distribute water throughout the western Al-Hammar marsh. These processes are significant to identify the current restoration problems and help to create restoration strategies for the marsh. Also, proper management strategy to the Al-Hammar marsh is necessary to preserve the marsh ecosystem, irrigate lands, and provide domestic necessities in the villages.

The overall project is divided into three main chapters which address the current ecological and hydrological …

Groundwater-Surface Water Interaction In The Headwater Of The White River, Manistee National Forest, Michigan, Ziqian Li

Masters Theses

Groundwater is a significant fresh water source in most areas and can be affected by potential changes to climate and precipitation from anthropogenic influences. Considering groundwater and surface water can be regarded as one hydrologic system, it is significant to understand the dynamics between precipitation, shallow groundwater and surface water in order to manage these resources.

Water samples were collected roughly biweekly from July 2016 to June 2017, and analyzed for electrical conductivity and stable isotopes of oxygen and hydrogen. During sample collection site visits, stream discharge and the groundwater heads from different wells were measured.

The stable isotopes of …

Deriving Landscape-Scale Vegetation Cover And Aboveground Biomass In A Semi-Arid Ecosystem Using Imaging Spectroscopy, Andrew Poley

Boise State University Theses and Dissertations

Environmental disturbances in semi-arid ecosystems have highlighted the need to monitor current and future vegetation conditions across the landscape. Imaging spectroscopy provide the necessary information to derive vegetation characteristics at high-spatial resolutions across large geographic areas. The work of this thesis is divided into two sections focused on using imaging spectroscopy to estimate and classify vegetation cover, and approximate aboveground biomass in a semi-arid ecosystem.

The first half of this thesis assesses the ability of imaging spectroscopy to derive vegetation classes and their respective cover across large environmental gradients and ecotones often associated with semi-arid ecosystems. Optimal endmember selection and …

Fungi Of Forests: Examining The Diversity Of Root-Associated Fungi And Their Responses To Acid Deposition, Donald Jay Nelsen

Graduate Theses and Dissertations

Global importance of forests is difficult to overestimate, given their role in oxygen production, ecological roles in nutrient cycling and supporting numerous living species, and economic value for industry and as recreational zones. Fitness of the forest-forming trees strongly depends on microbial communities associated with tree roots. In particular, fungi impact tree fitness: mycorrhizal species provide water and nutrients for the trees in exchange for C, endophytic fungi play key roles in host defense against pathogenic organisms, and saprotrophic fungi decompose dead organic matter and facilitate nutrient cycling. In addition, pathogenic fungal species strongly affect forest fitness. Despite their importance, …

Population Dynamics Of Ouachita Dusky Salamanders (Desmognathus Brimleyorum) In A Managed Forest Landscape, Kelly Marie Halloran

Graduate Theses and Dissertations

With anthropogenic alteration of landscapes increasing world-wide, managed forests are increasingly important as providers of ecosystem services including habitat for numerous wildlife species. It is crucial to maintain a balance between timber production and conservation of biodiversity on managed landscapes. Salamander populations can play key roles in the function and diversity of temperate forest ecosystems. Several studies have reported negative effects of forestry on terrestrial plethodontid salamanders, but less research has focused on stream-dwelling species, evaluated mechanisms driving observed shifts in abundance, or described the dynamics of populations residing in managed forests. Using a Before-After-Control-Impact design, we examined the effects …

Design And Implementation Of A Multi-Port Solid State Transformer For Flexible Der Integration, Mohammad Rashidi

Theses and Dissertations

Conventional power system includes four major sections, bulk generation, transmission network, distribution network, and loads. The main converter in the conventional electric grid is the low-frequency passive transformer providing galvanic isolation and voltage regulation for various voltage zones. In this configuration, small-scale renewable energy resources are generally connected to the power system at low voltage zones or inside microgrids.

Recent developments in the design of power electronic elements with higher voltage and power ratings and medium/high frequency enable making use of solid state transformer at different voltage levels in the distribution system and microgrid design. In this work, the concept …

The Influence Of Road Salt On Seasonal Mixing And Redox Stratification In Three Southwest Michigan Kettle Lakes, Danielle Dupuis

Masters Theses

Influxes of saline water from roads treated with deicers can alter the density structure of urban lakes. This can delay or halt turnover events, which may lead to persistent hypolimnetic anoxia in nutrient-rich lakes. In this study, the lake columns of two urban lakes (Woods Lake and Asylum Lake) and one rural lake (North Lake), were sampled once a month from March 2016 to June 2017. Lake column water was analyzed for conductivity, temperature, dissolved oxygen, ferrous iron, manganese, sulfide, calcium, magnesium, sodium, chloride and methane concentrations as a function of depth. All three lakes are eutrophic with anoxic hypolimnia …

Emerging Infectious Disease And The Imperiled Relict Leopard Frog, Anthony Wayne Waddle

UNLV Theses, Dissertations, Professional Papers, and Capstones

The disease chytridiomycosis, caused by the aquatic fungal pathogen Batrachochytrium dendrobatidis (Bd), has emerged as a major contributing factor for worldwide amphibian declines. Although relatively recently described, the impacts from the disease this pathogen causes have been definitively tied to amphibian declines, including some that occurred decades ago. In some cases, declines of individual species occurred with little documentation and are thus poorly understood. The relict leopard frog (Rana onca = Lithobates onca) has experienced such a decline and by the latter part of the 20th century only occurred in two general areas in southern Nevada. Recent research has found …

Rancher Perceptions Of Ecosystem Services From Rangelands Of The Intermountain West, Elisabeth C. York

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rangelands within the Great Basin are responsible for the provision of multiple resources that humans depend on for a variety of reasons. Ranchers in this region are dependent on public lands to remain economically viable in their cattle operations. As a majority of land in this region is publically owned, there are varying interests at play in what should and could be the focus of management. Ranchers are charged with implementing strategies aimed at conserving these landscapes and their motivations for what to manage may significantly influence resource provision from Intermountain West ecosystem.

In this study, I sought to understand …

Longitudinal Thermal And Solute Dynamics In Regulated Rivers, Muhammad Rezaul Haider

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dam releases increase river stage and can reverse groundwater movement into and out of the river. As the flood, thermal, and solute waves travel downstream in a regulated river, the size of the waves is anticipated to be affected both by river processes and exchanges with near river groundwater. This study established a modeling framework to quantify the influences of the groundwater exchanges on the temperatures and solute concentration dynamics along regulated rivers. The wave properties, volume of exchanges, conservative solute mass exchanges, and heat energy exchanges were calculated as a function of time and distance downstream. Results show that …

Exploring And Describing The Spatial And Temporal Dynamics Of Medusahead In The Channeled Scablands Of Eastern Washington Using Remote Sensing Techniques, Timothy M. Bateman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Medusahead is a harmful weed that is invading public lands in the West. The invasion is a serious concern to the public because it can reduce forage for livestock and wildlife, increase fire frequency, alter important ecosystem cycles (like water), reduce recreational activities, and produce landscapes that are aesthetically unpleasing. Invasions can drive up costs that generally require taxpayer’s dollars. Medusahead seedlings typically spread to new areas by attaching itself to passing objects (e.g. vehicles, animals, clothing) where it can quickly begin to affect plants communities. To be effective, management plans need to be sustainable, informed, and considerate to invasion …

Optimizing Barrier Removal To Restore Connectivity In Utah’S Weber Basin, Maggi Kraft

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

River barriers, such as dams, culverts and diversions are important for water conveyance, but disrupt river ecosystems and hydrologic processes. River barrier removal is increasingly used to restore and improve river habitat and connectivity. Most past barrier removal projects prioritized individual barriers using score-and-rank techniques, neglecting the spatial structure and cumulative change from multiple barrier removals. Similarly, most water demand models satisfy human water uses or, only prioritize aquatic habitat, failing to include both human and environmental water use benefits. In this study, a dual objective optimization model identified in-stream barriers that impede quality-weighted aquatic habitat connectivity for Bonneville cutthroat …