Oceanography and Atmospheric Sciences and Meteorology Commons^™

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.

2026 May - Tennessee Monthly Climate Report, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Monthly Reports

Hi All,

The main weather and climate story for May 2026 across Tennessee was the weather whiplash that many experienced with severe and extreme drought conditions giving way to flash flooding later in the month. Additionally, many saw large and rapid temperature swings with two strong blasts of cold air sending temperatures into the 30’s or low 40’s for many early in the month and again on May 14-15. Followed by a heat wave that brought an early taste of summer to the state from May 16-21. The Bristol/Tri-Cities airport experienced a 2-day span between freezing temperatures and 90-degree heat …

Modeling The Effects Of Low-Pressure Atmospheric Fronts On Sediment Transport Through Mississippi Sound Barrier Island Inlets, Nicholas J. Gagliano

Master's Theses

Coastal sediment dynamics in the Mississippi Sound are strongly influenced by tropical cyclones and the more frequent passage of low-pressure atmospheric fronts. While hurricanes are well recognized for reshaping barrier islands and altering sediment budgets, the cumulative role of recurrent fronts remains poorly quantified. This thesis investigates the impacts of six low-pressure atmospheric fronts (2015–2017) on sediment flux through six barrier island inlets in the Mississippi Sound.

A high-resolution application of the Regional Ocean Modeling System with the Community Sediment Transport Modeling System was developed to simulate tidal circulation, wind-driven currents, and sediment dynamics. Waves were excluded from the simulations. …

Modeling Water Quality And Cyanobacteria Blooms In St. Lucie Estuary, Florida, Mohmmad Masudur Rahman

Electronic Theses and Dissertations 2020 - Present

The St. Lucie Estuary (SLE) on Florida’s east coast is vital for diverse aquatic life and provides essential services to local communities. However, the estuary’s health is threatened by water quality deterioration due to nutrient-driven phytoplankton blooms, particularly cyanobacteria, which have increased in frequency over recent decades. These blooms may worsen water quality by reducing dissolved oxygen, altering pH, and increasing turbidity. Moreover, some phytoplankton species, including Microcystis aeruginosa, a freshwater cyanobacteria species, produce harmful toxins, posing risks to both marine aquatic life and human health in this area. Primary nutrient sources in this estuary include watershed freshwater discharges, …

2026 April 30 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.

Assessment Of Morphological Differences And Genetic Variation In Head Shape Of Florida Pompano Trachinotus Carolinus, Neriah Nicholas

Electronic Theses and Dissertations 2020 - Present

Genomics research can inform selective breeding programs to improve broodstock and seedstock quality for the U.S. warmwater marine finfish aquaculture industry. Florida pompano Trachinotus carolinus serves as a model species for the industry due to its commercial value and ability to spawn in captivity. This study examined a growth abnormality observed in commercially produced juveniles in partnership with Aquaco Farms LLC. Twenty fish were collected, culled, and euthanized by Aquaco staff, then classified into two head types: “normal” and “concaved”. Eleven morphological measurements were recorded before and after freezing to assess head variation and storage effects. DNA from pectoral fin …

Warming Climate Amplifies Vapor Pressure Deficit Limits On Gross Primary Productivity, Shiqin Xu, Nate G. Mcdowell, Tim R. Mcvicar, Diego G. Miralles, Stephen Sitch, Pablo Sanchez-Martinez, Joshua B. Fisher, Pierre Friedlingstein, Hylke E. Beck, Matthew F. Mccabe

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Ongoing climate warming may profoundly impact terrestrial gross primary productivity (GPP), a key component of the global carbon cycle. However, uncertainty in the relative roles of atmospheric water demand (vapor pressure deficit, VPD) and root-zone soil moisture (SM) limits predictions of drought impacts on GPP. Here, we show that growing-season GPP was more strongly constrained by VPD than SM globally, based on observation-constrained model estimates, satellite retrievals and Dynamic Global Vegetation Model simulations. The importance of VPD increased with higher temperatures and more severe and prolonged droughts. This pattern reflects VPD’s critical role in regulating stomatal conductance and plant hydraulic …

Assessing Hyperlocal And Local Air Quality Through Passive Samplers And Low-Cost Monitors, Yan He

McKelvey School of Engineering Graduate Student Theses & Dissertations

Air pollution is a major environmental health concern and has been associated with respiratory disease, cardiovascular morbidity, metabolic disorders, premature mortality, and additional adverse health outcomes. Air pollution often exhibits substantial variability at fine spatial scales, yet conventional regulatory monitoring networks are too sparse to resolve neighborhood-level exposure gradients that may exist in many urban and rural communities. Hyperlocal differences in pollutant concentrations—driven by local emission sources, land use characteristics, atmospheric chemistry, and meteorological conditions—can lead to systematic differences in long-term exposure among populations living only short distances apart. Improving exposure characterization therefore requires dense monitoring strategies and spatial modeling …

The Atmospheric Effects On The Extratropical Transition Of Hurricane Sandy, Natalie Paone

Ocean Engineering and Marine Sciences Student Publications

• Hurricane Sandy formed in the Caribbean in late October 2012 and intensified to a Category 3 hurricane before making landfall in Cuba and later New Jersey (Blake et al., 2013). Sandy caused approximately $68.7 billion in damages and over 250 fatalities, making it one of the most impactful storms in U.S. history. 
• During extratropical transition (ET), tropical cyclones interact with midlatitude systems, leading to structural changes such as expansion of the wind field, development of frontal boundaries, and increased baroclinicity (Hart and Evans, 2001). Sandy is a key example of a hybrid cyclone where ET did not weaken impacts but …

Tiny Engineers: How Polycheateworms Can Extend Sedimentary Oxic Layers And Create Better Seagrass Habitats, Natalie Spohn

Ocean Engineering and Marine Sciences Student Publications

The Indian River Lagoon (IRL) is a shallow, well mixed estuary on the East Coast of Florida. Presently, the IRL is suffering eutrophication due to a cycle of harmful algal blooms (HABs) that deplete the water column of oxygen (2,5). Deposition of organic matter from HABs in the sediment leads to reduced sedimentary oxygen, continuing to support the cycle of eutrophication through benthic-pelagic coupling (1,5). Anaerobic sedimentary conditions can increase concentrations of ammonium and sulfide, leading to seagrass loss (3,4,6,7,10). Bioturbation by infauna can extend the oxic layer of sediments, promoting aerobic processes and helping to remove nitrogen and sulfur …

Ontogeny Of Microbial Community Structure In Shoal Grass Grown In Biochar-Amended Sediments, Sajeda Slhoub, Nicole Katz, Joey Ciocher, Jack Denvir, Jenisse Louis, Katelynn Zagami

Ocean Engineering and Marine Sciences Student Publications

The Indian River Lagoon (IRL) is one of the most biologically diverse estuaries in the United States and contributes over $55.4 billion annually to Florida’s economy. Since 2010, more than 52% of the IRL seagrass meadows have been lost, reducing both the ecological and the economic potential of this ecosystem. Biochar, a stable carbon material produced by pyrolysis, added to soil enhance organic productivity perhaps because of increased microbial activity in the soil (Lehmann et al., 2017). Our study evaluates the use of biochar to grow resilient strains of seagrass for ecosystem restoration in the IRL.

N.A.U.T.I.L.U.S.: Natural Aquaculture Using Technology In Living Underwater Systems, Joey Ciocher, Abby Vallejo, Will Marble, Martin Pham, Roger Jiang

Ocean Engineering and Marine Sciences Student Publications

Marine protected areas (MPAs) are small subsets of marine ecosystems with limited to no access to exploitation to promote sustainability and growth of healthy populations of marine organisms. Factors that affect the performance of MPAs include Size, Age, Level of Protection, Enforcement and Compliance, Isolation and Connectivity, and Habitat Quality and Diversity.

Thermoelectric Migraine Cooling Cap, Emily Ralston

Ocean Engineering and Marine Sciences Student Publications

Migraines affect millions of people and can cause serious pain and discomfort. Many people use ice packs or cooling wraps to try to reduce the pain, but these only stay cold for a short amount of time. Because of this, there is a need for a cooling system that can provide longer and more controlled cooling. This project focuses on designing and building a wearable cooling cap that uses thermoelectric cooling technology. The goal is to create a system that can cool the head while moving heat away toward the neck area and help reduce migraine discomfort.

Factors Contributing To The Intensity Of Two 2022 Lake Effect Snowstorms At Lake Erie, Johnny Murray

Ocean Engineering and Marine Sciences Student Publications

• Lake effect snow (LES) is a weather phenomenon in which cold mass air passes over relatively warm waters, forming localized bands of snowfall. (Niziol, 1987) 
• LES events are common during the winter months in Buffalo, NY due to the city’s location along the northeastern edge of Lake Erie.
• November 17-20 and December 23-27 in 2022 were two prominent LES events.
• Total maximum snowfall for the events were 81.2” in Nov and 51.9” in Dec. 
• High snowfall totals were in part due to the length of these events, being ~60 hours in Nov, and ~120 hours in Dec.

Correlation Between Particulate Matter And Aerosol Optical Depth Following The 2023 Wildfire Smoke Event In Nyc, Trinity Abraham

Ocean Engineering and Marine Sciences Student Publications

• In June 2023, Canadian wildfires transported smoke into NE U.S., impacting air quality in places such as NYC (Figure 1)
• Climate change increases wildfire frequency and intensity, raising the likelihood of future longrange smoke transport events (NASA, 2025) 
• PM₂.₅ and PM₁₀ refers to the mixture of solid particles and liquid droplets in the air that can penetrate the respiratory system (U.S. Environmental Protection Agency, 2025)
• AOD measures how light is affected by aerosols, with higher AOD indicating greater aerosol concentrations (NASA Earth Data)
• Investigating the relationship between AOD and surface PM concentrations can improve early warning systems to support preparedness …

Microgravity Simulator, Aruna Dookeran, Alexander Montano, Elias Orellana, Aiden Smart

Ocean Engineering and Marine Sciences Student Publications

Microgravity significantly affects biological growth, but space-based experiments are costly and difficult to access. Ground-based systems provide an alternative; however, many require continuous manual supervision to maintain operating conditions.

Assessment Of Goose-Beaked Whale Responsesto Mid-Frequency Active Sonar Usinga Hierarchical Hidden Markov Model, Stacy L. De Ruiter, Erin A. Falcone, Shannon N. Coates, Brenda K. Rone, David A. Sweeney, Karin A. Dolan, Susan M. Jarvis, Russel D. Andrews, Stephanie L. Watwood, Gregory S. Schorr

University Faculty Publications and Creative Works

Background

Acoustic disturbance is increasingly recognized as an ecological concern, particularly at sea. In light of marine mammal stranding events associated with use of naval mid-frequency active sonar (MFAS), which often involve goose-beaked whales (Ziphius cavirostris), research has sought to detect and characterize Ziphius behavioral responses to MFAS.

Methods

We deployed Sound and Motion Recording and Telemetry (SMRT) tags on 13 Ziphius in the Southern California Bight. The study area includes the United States Navy’s Southern California Anti-submarine Warfare Range (SOAR), and deployments overlapped temporally with training exercises including MFAS use. We used hierarchical hidden Markov models (HHMMs), which provided …

Hydrodynamic Response To Hurricane Forcing At Sebastian Inlet, Ava Russin

Ocean Engineering and Marine Sciences Student Publications

Tidal inlets are influenced by tides, wind, and atmospheric forcing, which can be significantly altered during hurricanes. Using Acoustic Doppler Current Profiler observations, this study quantifies storm-driven changes in depth averaged velocity and residual circulation at Sebastain Inlet before, during, and after Hurrican Ian and Hurricane Nicole (2022).

Era5 Vs Asos: Verifying Reanalysis Accuracy In The Fort Pierce Ef3 Tornado, Anastasia Vosinakis

Ocean Engineering and Marine Sciences Student Publications

• October 9th, 2024, Hurricane Milton made landfall in Florida (NHC, 2024). 
• Just before Milton made landfall, tornadoes were being produced on the East Coast of Florida. 
• The tornado being studied is the EF3 tornado which occurred in Fort Pierce, Florida. 
• Six people tragically lost their lives. 
• Focus of project: to see the correlation of wind reanalysis data when studying tornadoes.

Conservation Of Stress And Immune Gene Families Across Major Aquaculture Fish Species, Julia Pearson, Rana Alghorir, Maryam Young, Abby Briggs, Sonia Peters

Ocean Engineering and Marine Sciences Student Publications

Aquaculture environments impose thermal, oxidative, and immune stress. Successful species must maintain cellular stability under these conditions. They can do this by the relative expression of stress genes.