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Should I Stay Or Should I Go?: Evaluating The Role Of Climate And Weather Stressors On Moving Decisions In Southeast Florida, Arielle Perry

Electronic Theses and Dissertations

As climate and weather hazards intensify, Southeast Florida communities face mounting pressures that increasingly influence patterns of migration and immobility. This research examines evidence of climate migration in high flood-risk neighborhoods in Fort Lauderdale by exploring why some populations choose to stay, while others leave, in the context of a changing climate. Using focus group discussions, I investigate how climate and non-climate related factors shape mobility outcomes among residents in the city. Migration outcomes were primarily influenced by negative climate and weather hazard experiences, discontent with existing public in-situ adaptations, and non-climate disamenities, which eroded participants’ sense of place. Voluntary …

Red Lines, Green Blooms: Assessing The Effects Of Historical Environmental Disparity On Algal Communities In The Twin Cities, Mn, Georgia C. Akins

Environmental Studies Honors Projects

Redlining, a discriminatory housing policy from the 1930s, shaped lastng urban inequalites that may extend to environmental conditons. This study examines links between redlining and urban water quality in the Twin Cites using algal communites as indicators. Across 28 water bodies sampled in 2022 and 2024, physical, chemical, and biological metrics were compared by redlining grade. Results show limited relatonships between redlining and most variables, with only surface water temperature differing significantly. Nutrients and algal diversity were unrelated to redlining, instead reflectng present-day conditons. These findings suggest contemporary factors play a stronger role than redlining in shaping urban freshwater ecosystems.

Fossil-Fuels In A Decarbonized Country? Modeling The Drivers Of Icelandic Oil Sales, Inbal Armony

Environmental Studies Honors Projects

Although 100% of Iceland’s electricity comes from renewable energy sources, it still relies on fossil fuels for land transportation, marine transportation, aviation, and some industry. Understanding geographic nuances in oil use is critical to achieving Iceland’s goals of carbon neutrality by 2040. As the island has one primary urban center with two thirds of the population, information is lacking about oil use in non-Capital areas and a gap between state and municipal climate plans. Using newly available data of oil sales at the municipality-level in a Small Area Estimation model, we analyze drivers of oil sales across Icelandic municipalities. We …

Tissue-Specific Heavy Metal Accumulation And Sediment–Mangrove Dynamics In Port Everglades, Florida, Dimitrios Giarikos, Amy Hirons, Jason Gershman, Sophie Welch

SECLER Data

Coastal wetlands near industrialized waterways face increasing heavy metal contamination, yet the role of mangroves as biogeochemical buffers remains poorly understood. This study quantified 16 heavy metals in sediments and red mangrove (Rhizophora mangle) tissues (roots, branches, and leaves) across four sites near Port Everglades, Florida, examining tissue-specific partitioning, contamination patterns, and sediment-to-plant transfer. The South Turning Basin (STB) was the principal contamination hotspot, with geometric mean (GM) concentrations of arsenic (As; 27.8 µg/g) and zinc (Zn; 203 µg/g) exceeding threshold effect levels, while Cu exceeded its probable effect level (PEL; 193 µg/g). Mercury (Hg) exceeded its PEL …

Chemometric Analysis Of Dissolved Organic Matter Using Fluorescence, Dani Fellner, Ken Overway

Honors Projects

Univariate spectroscopic techniques have been utilized to measure dissolved organic matter (DOM), but challenges arise in the separation and characterization due to similarities in chemical structures and spectral overlap. Multivariate techniques utilize a combination of known analytes with their unique excitation and emission spectra from fluorescence measurements to quantify amount of each analyte present in the mixture using parallel factor analysis. Tryptophan, tyrosine, and phenylalanine are common amino acids found in environmental samples and can be quantified due to their intrinsic fluorescence qualities. These amino acids can be utilized to estimate the amount of DOM in a sample since proteins …

Environmental Sustainability Assessment Of Field Phosphate Monitoring Methods For Creeks, Quintino Medi

All Theses

Creeks serve as conduits for water, nutrients, and contaminants to larger water bodies such as rivers and lakes, and their health is a key indicator of overall watershed water quality condition. Unlike rivers, creeks are under-monitored due to their small size, hydrological variability, and limited accessibility. Many technologies exist for monitoring phosphorus in surface waters. Technologies may be classified into two general categories: i) proxy real-time sensors, which record generic water quality parameters, and ii) chemical reagent-based assays, which quantify soluble reactive phosphorus (SRP) in batch samples. There is a lack of studies that compare the features and benefits of …

Soil Moisture Regime Effects On Near-Surface Soil Chemical Properties In Alfisols Under Native Tallgrass Prairie In Arkansas, Sydney M. Talley

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Tallgrass prairie ecosystems provide many crucial ecosystem services, including nutrient cycling and storage, organism habitat, and soil and water conservation. However, tallgrass prairies are considered an endangered ecosystem, particularly in the Ozark Highlands and Grand Prairie regions of Arkansas, where less than 0.05% of Arkansas’ original prairie land area remains. Understanding soil nutrient supplies over time in native tallgrass prairie ecosystems is critical for quantifying the success of restoration and rehabilitation activities. The objective of this study was to evaluate the effects of soil moisture regime (SMR) (i.e., aquic and udic), region (i.e., Ozark Highlands and Grand Prairie), and their …

Community Resilience And Response To Salinity Gradients In Streams Flowing Into Biscayne Bay, Florida, Sebastian M. Jimenez

Honors Theses

Salinity is a shaping force of aquatic biodiversity, and ongoing climate change and unsustainable water-management practices are causing salinity-induced stress across coastal ecosystems. Meiofauna are small (45-1000 μm), taxonomically diverse aquatic invertebrates that are vital to ecosystems and highly responsive to environmental disturbances, making them ideal for assessing the effects of changing salinities on community structure. This study investigated how meiofaunal biodiversity (ASV richness, Faith’s phylogenetic diversity, and community composition) responded to natural salinity gradients along streams flowing into Biscayne Bay, South Florida, which is a region particularly vulnerable to salinization due to sea-level rise, altered hydrology, and watershed modification. …

Bottles, Butterflies, And Biomass: Recycled Glass Sand, Microbial Additions, And Herbivory Effects On Milkweed Growth, Kealey Skinner

Honors Theses

Plant-soil-microbe interactions are integral components of ecological networks and drive ecosystem function from the bottom-up. Whereas herbivores regulate ecosystem function from the top-down, having opposing and potentially complementary effects on ecosystem function. My thesis sought to understand how below-ground microbial communities contribute to herbivore preference and plant biomass across varied soil substrates. My thesis asked: how do substrate and soil microbial communities influence herbivore preference and plant biomass accumulation on swamp milkweed (Asclepias incarnata)? To address this question, seedlings of A. incarnata were sown in 2.5 cm wide × 10 cm deep pots filled with either natural beach sand or …

Enhancing Food Security In Stann Creek. Belize Using Meat Rabbits, Lindsey Garretson

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

In recent years, food insecurity and the prevalence of hunger have rapidly grown throughout the world, but especially within Latin America and the Caribbean. Along with growing rates of food insecurity and hunger there are increases in medical conditions including negative impacts the functioning of every major organ system, increased rates of mental illness, both overweight and underweight children, wasting in both children and adults, and anemia. Availability and access to healthy, nutritional food options can help lower the risk of these conditions. With these considerations, the goal of this project was to create an all-encompassing manual and construction guide …

Herbivory Of Phragmites Australis Along A Salinity Gradient In Connecticut Wetlands, Sydney H. Kolz

Honors Scholar Theses

Invasive Phragmites australis (common reed) is widely distributed in New England wetlands, where it often outcompetes native plants and decreases biodiversity throughout the food web. Controlling its invasion is a priority, especially in salt marsh habitat, but current management techniques are inefficient. Leveraging natural processes may improve control strategies, but in order to do so, we must first better understand how abiotic and biotic stressors interact and affect Phragmites. This study focuses on herbivory and salinity, two factors limiting Phragmites’ fitness. I measured soil salinity and quantified the damage of three herbivore guilds (i.e. gall-formers and stem-borers, leaf-chewers, and …

Investigating The Taxonomic Uncertainties Of Potentilla Rupincola, Natalie Elizabeth Hieber

Master's Theses

Landscape stewardship is an integral role for land managers that becomes more important when rare or endangered species occur within managed areas. Conservation across the landscape is a primary concern for land managers, but resources allocated for conservation can be limited due to many competing goals. Taxonomic uncertainty surrounding rare and endangered taxa, particularly plant taxa, that have historically been classified solely using morphological features further complicates conservation planning. One such taxon is Potentilla rupincola, a rare plant endemic to the eastern Rocky Mountains in Colorado. For over a century, botanists have debated whether P. rupincola is a distinct species …

The Effects Of Impervious Land Cover And Red Tide (Karenia Brevis) On The Florida Manatee (Trichechus Manatus Latirostris) In The Gulf Coast Of Florida, Anna Compton

Honors College Theses

Red tide, caused by the dinoflagellate Karenia brevis, is an algal bloom event that occurs annually in the West Florida Continental Shelf. The algae releases brevetoxin, a toxin that can be fatal to wildlife in high concentrations. These algal bloom events are thought to be exacerbated by warming ocean temperatures and increased nutrient runoff from urbanization. Red tide is responsible for the mass mortality of various marine organisms like the Florida manatee (Trichechus manatus latirostris). This study analyzes the changes in nutrient runoff and sea surface temperatures, and how these factors affected red tide cell concentrations and Florida manatee mortalities …

2026 Workshop On Bridging The Gaps: Tackling Microplastics And Nanoplastics Challenges In Coastal Ecosystems, Shenghua Wu, Kaushik Venkiteshwaran, Melike Dizbay-Onat, Alexandra Stenson, Jinhui Wang, Tina Miller-Way, Ebenezer Nyadjro, Bhuvnesh Bharti, John Weinstein, Yi Bao, Shihui Shen, Valerie Longa, Shenghua Zha, John Cleary, Marty Lind

Workshops

This report presents the findings from the 2026 Workshop on Tackling Microplastics and Nanoplastics (MNPs) in Coastal Ecosystems, which took place in Mobile, Alabama. More than 140 experts from universities, government, industry, and community organizations gathered to address the increasing issue of MNPs in coastal regions.

Foraging Plasticity And Mercury Contamination In Red-Legged Kittiwakes: A Multiple Stressor Perspective, Sam E. Clay

All-Inclusive List of Electronic Theses and Dissertations

Arctic seabirds are facing increasing stress from climate change, yet the interactive effects of multiple stressors on behavior remain poorly understood. Adopting a multiple stressor perspective promises to advance understanding of avian behavioral responses to climate change, as climate change is exposing Arctic and subarctic animals to a complex set of stressors rather than a single stressor in isolation. Using the red-legged kittiwake (Rissa brevirostris) as a model, I examined how multiple stressors, including mercury (Hg) exposure, shifting wind conditions, and varying foraging conditions linked to sea surface temperature (SST) may interact to constrain behavioral plasticity and energetically expensive behavior …

Dendroclimatic Response Of The Wet Miombo Woodland Species: A Case Study Of Mufulira District, Copperbelt Province, Zambia, Collins Chibuye Malubeni

All-Inclusive List of Electronic Theses and Dissertations

Zambia is a tropical, landlocked country that lies in the South-Central part of Africa. The climate in Zambia includes distinct dry and rainy seasons, mainly influenced by the north-south movement of the Intertropical Convergence Zone (ITCZ), which shifts seasonally. This research is focused on understanding the relationship between tree growth and climate using dendrochronology. Forty-nine tropical species, including Julbernardia paniculata, Brachystegia longifolia, and Pericopsis angolensis, were analysed for dendroclimatic potential, and 70% showed clear ring formation, indicating that trees in this locality produce distinct annual ring boundaries. For the single species chronology, thirteen cores from eight trees that were initially …

Microplastic Composition And Exposure Pathways In Freshwater Systems: A Multi-Matrix Comparison Between Streams And Retention Ponds In Hamilton County, In, Mya Whaley

All-Inclusive List of Electronic Theses and Dissertations

Since the early 1900s, the use of plastics has increased exponentially. The breakdown of plastic materials has exposed all ecosystems to microplastics (small particles of plastic < 5 mm), which are now ubiquitous in natural settings. Microplastics have a relatively large surface area, and many chemicals adsorb to these small particles, impacting their fate and transport of pollution. While microplastics have been found in virtually every setting on Earth, research is necessary to understand their impact on freshwater ecosystems and biogeochemical cycles. The focus of this research was to investigate microplastic compositions in crayfish, sediments, and water samples collected in streams and retention ponds. We analyzed trends in microplastic counts across different land-cover classes, waterbody types, and species, and compared concentrations among matrices to improve our understanding of microplastic exposure pathways in freshwater ecosystems. As a secondary objective, lead and arsenic concentrations were analyzed from sediment samples to investigate metal burdens and compare them to microplastic concentrations. Our findings revealed that, in general, urban streams had the highest microplastic concentrations within land cover categories, and retention ponds had higher microplastic counts than streams. Crayfish, such as F. rusticus had higher microplastic concentrations than F. virilis and F. propinquus, although these results may be influenced by study design. The most common microplastic type was fibers, and most common color was transparent. There was no significant correlation between microplastic and metal concentrations in sediments. We found crayfish to be adequate bioindicators of microplastic pollution, because they were less impacted by environmental variability than sediment and water samples. This research presents the first evidence of microplastics in our study species, F. propinquus, F. rusticus, and F. virlis. This work presents new evidence of microplastic accumulation in crayfish, sediments, and water from freshwater systems in the Midwestern United States. Microplastics were found in every sample type—crayfish, water, and sediment—across urban, rural, and forested landscapes, highlighting their pervasive distribution. The findings provide foundational data for assessing emerging ecological and human-health risks and emphasize the importance of sustained monitoring and research on MP contamination in freshwater environments.

The Environment, Health, And Vector Nexus: Evaluating The Spatiotemporal Variability And Societal Impact Of Ticks In Arkansas, Dalton Williams

Graduate Theses and Dissertations

Tick-borne diseases (TBDs) are a surging public health and veterinary concern in the United States. In states like Arkansas, climate change and shifting land use have recalibrated the ecological niches of vector species. This research utilizes species distribution and ecological niche modeling to assess the spatiotemporal suitability of ixodid tick habitats, specifically where environmental and socioeconomic factors intersect. By integrating spatial science with public health frameworks, this study identifies priority intervention areas in underserved rural regions where healthcare resources are often constrained. This study provides a comprehensive methodological framework, leveraging remote sensing datasets and historic disease data to delineate exposure …

Assessment Of Mississippi Landfill Capacity In Relation To Waste Generation And Land-Use Constraints, Jason C. Anderson

Master's Theses

Municipal solid waste (MSW) management presents a growing challenge in Mississippi as population trends, socioeconomic change and regional development continue to place pressure on existing landfill capacity. This thesis examines waste generation and disposal patterns from 2000 through 2022 across Mississippi counties, with projections extending to 2050. Historical landfill tonnage data was gathered and compiled from the Mississippi Department of Environmental Quality (MDEQ) and analyzed using regression models in Excel and RStudio, with forecasts generated for both in-state and out-of-state waste flow. Results highlight significant variations among landfills, including differing closure timelines, changing county service areas and notable shifts in …

Quantifying Discard Mortality Of Undersized And Ovigerous Crabs In The Gulf Of Mexico Blue Crab Fishery, Micayla Cochran

Master's Theses

Blue crabs support a valuable commercial fishery in the Gulf of Mexico. Most states require the release of undersized and ovigerous blue crabs, yet mortality of these discarded crabs is an understudied component of total mortality. The first objective of this project was to quantify discard mortality of non-target crabs using bycatch surveys across the Lake Pontchartrain–Mississippi Sound coastal system. Ovigerous crabs were most common at high salinities and temperatures, whereas undersized crab presence was inversely correlated with soak time, temperature, and the number of crabs per trap, and also varied among geographic locations. A reflex action mortality prediction assessment …

Redeveloping Mississippi: A Case Study On Brownfields In Central & Southern Mississippi, Sahrah R. Yeroozedek

Master's Theses

Brownfields, or properties that are or possibly are contaminated with dangerous materials, represent a common obstacle for communities in Mississippi. The real or potential presence of contaminants at these sites often deters investors due to costly cleanup requirements (EPA, n.d. -b). The Environmental Protection Agency (EPA), through its Brownfield Revitalization Program, implemented guidelines for covering the costs and labor associated with the remediation of these properties. The EPA is not, however, responsible for redevelopment that supports long-term environmental and economic sustainability. Although the EPA maintains inventories of all Brownfields, there is also no comprehensive database of Brownfields and their current …

Evaluating The Effects Of Urbanization On Meiofauna Biodiversity In Chattanooga’S Lentic Ecosystems Through Gis Applications, Keyle M. Bryant

Honors Theses

Urbanization is a leading driver of biodiversity loss in freshwater ecosystems, yet its effects on meiofauna—microscopic invertebrates that serve as key bioindicators of ecosystem health—remain poorly understood in lentic environments. This study evaluated the effects of urbanization on meiofaunal biodiversity in ten lentic waterbodies across Hamilton County, Chattanooga, Tennessee, by integrating environmental DNA (eDNA) metabarcoding, in-situ abiotic measurements, and Geographic Information Systems (GIS)-based land use analysis. Water samples were collected between January and April 2023 and processed using 18S rRNA amplicon sequencing to assess biodiversity as richness (amplicon sequence variants or ASVs, phylogenetic diversity or PD, and community composition). Land …

Environmental Awareness And Community Sentiments In A Superfund Site: A Study Of South Chattanooga, Mia Dial

Honors Theses

The concept of environmental injustice refers to the disproportionate exposure of marginalized communities to environmental hazards, often resulting from the placement of industrial sites, waste facilities, or other environmentally harmful infrastructure in areas with limited political and economic power. Alton Park, a historically underserved neighborhood in Chattanooga, Tennessee, faces elevated environmental risks due to its proximity to the South Chattanooga Lead Superfund Site and legacy industrial contamination. This study used semi-structured individual interviews to assess community awareness, perceptions, and behaviors related to environmental hazards in Alton Park. Residents generally reported some awareness of the Superfund site, though knowledge was often …

Resilience By Living With The Land And Community: A Case Study Of A Local Food Forest, Olivia Beck

Honors Theses

Imagine a public space where food, leisure, outdoor activity, and community engagement occur in one place, all in an urban forest ecosystem. For many, this is a hopeful vision of the future, and that is exactly what the idea of an urban food forest provides. In agroecology, a food forest or forest garden consists of planting diverse edible plants and mimicking the patterns of natural ecosystems. The intricate planning and design ensure the forest is self-sustaining, much like a natural forest, making it very resilient once established. However, they face many challenges and take time to grow and develop to …

Growing Change: A Gis Spatial Analysis To Plan Urban Gardens In Chattanooga, Carson A. Chalk

Honors Theses

Food insecurity and limited access to fresh nutritious food in Chattanooga is a prevalent issue, primarily among lower socioeconomic households, and can put strain on overall well-being. This study aimed to identify suitable vacant parcels in Chattanooga where urban gardens could be developed using a GIS-based spatial analysis. Spatial data involving vacant parcels, slope, zoning, and proximity to grocery stores was cross referenced with socioeconomic data focused on poverty rates, vehicle ownership, and mean household income to identify the most suitable sites in areas of greatest need. Sites identified as suitable through GIS were then visited to verify their suitability. …

Geospatial Science And The Changing Environment: Applied Methods For Sustainable Agriculture And Landscape Management, Harrison Wakefield Smith

Graduate Theses and Dissertations

Rapid environmental change is disrupting agricultural productivity, ecological function, and the long-term resilience of managed landscapes. At the same time, the rapid growth of geospatial data science has improved our understanding of environmental change and increasingly is being used to improve sustainability in agricultural and environmental management. However, critical gaps remain that limit the applicability of data-driven insights in landscape management. This dissertation investigates the potential of geospatial analytics for sustainable agriculture and landscape management, with a focus on applied methods that operate across spatial and temporal scales. Using field, landscape, regional, and national datasets, it explores the capabilities and …

Fisheries Management Paper No. 313: Western Australian Statewide Small Pelagic Scalefish Resource Harvest Strategy, Department Of Primary Industries And Regional Development, Western Australia

Fisheries Management Papers

Harvest strategies for Western Australia’s (WA) aquatic resources are formal documents developed by the Department of Primary Industries and Regional Development (DPIRD, the Department) to support decision-making processes that ensure the outcomes are consistent with the principles of Ecologically Sustainable Development (ESD; Fletcher 2002a) and Ecosystem Based Fisheries Management (EBFM; Fletcher et al. 2012).

Harvest strategies are a key component of all contemporary fishery management systems and a requirement for certification under the Marine Stewardship Council (MSC; Marine Stewardship Council 2018). The objectives of ESD are reflected in the objects of the Fish Resources Management Act 1994 (FRMA).

This Statewide …

Population Structure And Connectivity Of Atlantic Nurse Sharks (Ginglymostoma Cirratum) In The Bahamas And Outlying Areas, Baylie A. Fadool

School of Natural Resources: Dissertations, Theses, and Student Research

Understanding animal ecosystem dynamics and behavior at the individual and population levels is essential for identifying life-history patterns and important areas for management and conservation. Marine fish species often face minimal geographic barriers to movement, but environmental (temperature, salinity, current) or intrinsic barriers (philopatry, site fidelity) can dictate gene flow. Atlantic nurse sharks (Ginglymostoma cirratum) are an International Union for Conservation of Nature (IUCN) listed ‘vulnerable’ species and present a unique opportunity to investigate patterns of population structure and connectivity in large-bodied sharks. They are benthic and display reproductive philopatry, with recent work suggesting they have the capacity …

Gaining Mussel: Evaluating Reintroduction Success Of Native Freshwater Mussels In Nebraska And Eastern Wyoming, Travis A. Moore

School of Natural Resources: Dissertations, Theses, and Student Research

Freshwater mussels are one of the most imperiled groups of organisms in North America, with over two-thirds of species considered threatened, endangered, or of special concern. These long-lived bivalves are essential to stream ecosystems, acting as filter feeders that improve water quality and as indicators of aquatic health. In Nebraska and Wyoming, native mussel populations have declined sharply due to habitat modification, pollution, and reduced connectivity. Two species of particular concern are the Plain Pocketbook Lampsilis cardium, listed as Tier I at-risk in Nebraska, and the Fatmucket Lampsilis siliquoidea, a Tier II at-risk species. In response, state agencies …

Impact Of Biomass Type On Hydrocarbon Yield And Chain Length Distribution Produced Via Fischer-Tropsch Synthesis, Nicholas R. Hawe

Honors Scholar Theses

This paper investigates the relationship between biomass composition and hydrocarbon yield as well as chain length distribution produced by Fischer-Tropsch synthesis. Through an Aspen Plus model, the conversion of three different biomasses – digestate, sawdust, and corn stover – into hydrocarbon fuel was simulated. The model converts biomass into gaseous and liquid hydrocarbons via various unit operations and reactions. Simulation results highlight the product distribution and hydrocarbon output, allowing for an analysis of hydrocarbon yield and comparison of chain length distributions amongst the three biomasses. Overall, the simulation showed biomass composition had no significant impact on hydrocarbon yield or chain …