Physical Sciences and Mathematics Commons^™

Comparison Of Otolith-Based Growth Rates And Microchemistry In Red Drum Before, During, And After The Deepwater Horizon Oil Spill, Brock Charles Houston

USF Tampa Graduate Theses and Dissertations

Oil from the Deepwater Horizon blowout reached the Gulf of Mexico coast in the summer of 2010 and potentially exposed species living in those areas to toxic chemicals. The purpose of this study is to examine otoliths from Red Drum (Sciaenops ocellatus) for evidence of oil exposure that could be related to reduced growth rates. Because otolith growth and somatic growth are directly related, differences in annulus measurements can indicate differences in annual somatic growth, which is a good indicator of overall fish condition, and translates into changes in survival and lifetime reproductive potential. This study assessed variation …

A Study On The Integration Of Multivariate Metocean, Ocean Circulation, And Trajectory Modeling Data With Static Geographic Information Systems For Better Marine Resources Management And Protection During Coastal Oil Spill Response – A Case Study And Gap Analysis On Northeastern Gulf Of Mexico Tidal Inlets, Richard Ray Knudsen

USF Tampa Graduate Theses and Dissertations

The Oil Pollution Act of 1990 requires the development of Regional and Area Contingency Plans. For more than 20 years, the State of Florida, under both the Department of Environmental Protection and the Florida Fish and Wildlife Commission, has worked closely with the U.S. Coast Guard and the National Oceanic and Atmospheric Administration to develop these plans for coastal and marine oil spill response. Current plans, developed with local, state and federal stakeholder input, use geographic information systems (GIS) data such as location and extent of sensitive ecological, wildlife, and human-use features (termed Environmental Sensitivity Index data), pre-defined protection priorities, …

Understanding Climate Change And Sea Level: A Case Study Of Middle School Student Comprehension And An Evaluation Of Tide Gauges Off The Panama Canal In The Pacific Ocean And Caribbean Sea, Juan Carlos Millan-Otoya

USF Tampa Graduate Theses and Dissertations

The present study had two main objectives. The first was to determine the degree of understanding of climate change, sea level and sea level rise among middle school students. Combining open-ended questions with likert-scaled questions, we identified student conceptions on these topics in 86 students from 7^th and 8^th grades during 2012 and 2013 before and after implementing a Curriculum Unit (CU). Additional information was obtained by adding drawings to the open-ended questions during the second year to gauge how student conceptions varied from a verbal and a visual perspective. Misconceptions were identified both pre- and post-CU among …

Influence Of Water Column Stratification And Nutrient Gradients On The Migratory Behavior Of The Red Tide Dinoflagellate, Karenia Brevis, Matthew Garrett

USF Tampa Graduate Theses and Dissertations

Diel vertical migration (DVM) can offer motile phytoplankton a competitive advantage over other phytoplankton species. DVM has been well documented in the harmful dinoflagellate, Karenia brevis; however, the extent to which changes in nutrient regimes and density stratification modify migration patterns has not been thoroughly investigated. A 2 m experimental column was constructed with sensors and sampling ports at four depths to obtain fluorescence and temperature measurements and discrete water samples. The environmental parameters of the experimental column represented temperature and nutrient conditions found on the West Florida Shelf (WFS), where Karenia blooms frequently occur. Results demonstrated a clear …

The Development Of A Fluorescence-Based Reverse Flow Injection Analysis (Rfia) Method For Quantifying Ammonium At Nanomolar Concentrations In Oligotrophic Seawater, William Abbott

USF Tampa Graduate Theses and Dissertations

The goal of this thesis was to adopt a reverse flow injection analysis (rFIA) technique to the fluorometric analysis of the reaction o-phthaldialdehyde (OPA) with ammonium, allowing accurate measurements of ammonium concentrations lower than the detection limit of the widely used indophenol blue (IPB) colorimetric method while accounting for the background fluorescence of seawater. Ammonium is considered an essential nutrient for primary productivity, especially in the nutrient depleted surface ocean where as the most reduced form of dissolved inorganic nitrogen, it is readily assimilated via metabolic pathways. Challenges in the quantification of ammonium require more sensitive analytical techniques for …

Saharan Air Layer Dust Loading: Effects On Convective Strength In Tropical Cloud Clusters, Randall J. Hergert

USF Tampa Graduate Theses and Dissertations

Numerous factors play a role in the development and maintenance of North Atlantic tropical cyclones as they originate and cross the Main Development Region. These factors include sea-surface temperatures (SSTs), relative humidity, vertical wind shear, etc. One key player in many of these factors is the Saharan Air Layer (SAL) which has been a source for study for nearly five decades.

The interplay between dust loading within the SAL and the development of African Easterly Waves (AEWs) has been repeatedly noted in many of the studies in this field. The cumulative indirect effect of the dust on AEWs however remains …

A Bat-Guano-Derived Δ15N And Δ13C Record Of Paleoenvironmental Change: Zidită Cave, Romania, Daniel Martin Cleary

USF Tampa Graduate Theses and Dissertations

Because nitrogen isotopes are fractionated along the soil-plant-insect-bat-guano pathway, it may be possible to reconstruct environmental and climatic changes reflected in the nitrogen isotopic composition of guano. A 1.5-m core of bat guano from Zidită Cave (western Romania) provides a record of climatic and anthropogenic influence on the regional nitrogen cycle and paleoenvironmental controls on nitrogen transforming processes. Increasing and decreasing trends of nitrogen isotopic composition (δ¹⁵N values) correspond well with changes in the influence of farming practices, deforestation, and forest expansion. These influences likely had a significant effect on the openness of the nitrogen cycle, resulting in …

Dissolved Nutrient Distributions In The Gulf Of Mexico Following The Deepwater Horizon Oil Spill, Ashley Ann Parks

USF Tampa Graduate Theses and Dissertations

The Deepwater Horizon (DWH) oil spill in the Gulf of Mexico (GoM) in the spring of 2010 introduced 4.4 million of barrels of oil to the ecosystem. Some biodegradation of the oil occurs when microorganisms, particularly bacteria, metabolize the oil as a carbon source. During this process, the microbes also require nutrients for energy. An introduction of oil at this magnitude has the ability to induce large blooms of microbes, which in turn can affect nutrient concentrations. Microbial petroleum degradation decreases nutrient concentrations, whereas the microbial assimilation and decay of organic matter increase nutrient concentrations. This study assessed whether any …

Ocean Forcing Of Quaternary East Antarctic Ice Sheet Evolution: An Ice-Proximal Sedimentary Perspective, Michelle E. Guitard

USF Tampa Graduate Theses and Dissertations

Antarctica and the Southern Ocean play a critical role in Earth’s climate system. Antarctica’s ice sheets contain enough ice to raise global sea level by ~58 m, and the Southern Ocean distributes climate signals and nutrients to the major ocean basins and the deep ocean. Antarctica’s largest ice sheet, the East Antarctic Ice Sheet (EAIS), was considered stable compared to those in West Antarctica and the Antarctic Peninsula because it was thought to be grounded above sea level. However, subglacial topography now reveals vast submarine basins and measurements of ice velocity in the Pacific sector indicate marine-terminating outlet glacier thinning …

Field Observations And Novel Methodologies For Carbon System Assessments In Coastal Waters, Bo Yang

USF Tampa Graduate Theses and Dissertations

Coastal zones receive massive terrestrial inputs of nutrients and organic matter, and play an important role in biogeochemical cycles. The interactions of river inputs, ocean currents, atmospheric exchanges, anthropogenic influences, and biologically active ecosystems make CO₂ system studies in coastal waters highly challenging. This work focuses on improving our understanding of the CO₂ system in coastal waters through (1) development of a new methodology for measurements of CO₂ system parameters in the field; (2) observations of large spatial and temporal CO₂ system variations in coastal waters; and (3) characterization of the influence of organics on CO …

Insights Into The Challenges Of Modeling The Atmospheric Boundary Layer, Esa-Matti Tastula

USF Tampa Graduate Theses and Dissertations

This work approaches the topic of modeling the atmospheric boundary layer in four research projects, which are summarized below.

i) The diurnal cycles of near-surface meteorological parameters over Antarctic sea ice in six widely used atmospheric reanalyses were validated against observations from Ice Station Weddell. The station drifted from February through May 1992 and provided the most extensive set of meteorological observations ever collected in the Antarctic sea ice zone. For the radiative and turbulent surface fluxes, both the amplitude and shape of the diurnal cycles varied considerably among different reanalyses. Near-surface temperature, specific humidity, and wind speed in the …

Population Dynamics Of The Little Gulper Shark (Centrophorus Uyato) And Community Analyses Of Elasmobranch Species In The Northern Gulf Of Mexico, Jacquelin Joye Hipes

USF Tampa Graduate Theses and Dissertations

In chapter 1 I describe the population dynamics of an understudied species of gulper shark, Centrophorus uyato (common name, the Little Gulper), found in the Northern Gulf of Mexico. Sharks in the family Centrophoridae are mid-sized, demersal fish, with seven species identified in North American waters. These deepwater species can be difficult to study due to the extreme depths at which they occur. During four longlining cruises from 2012-2014, 593 sharks were landed, predominantly in the Mississippi Canyon off the Louisiana coast. Mean depth of capture was 290 m. Supplementing these data are catch records for C. uyato from a …

Endocrine-Disrupting Compounds: Measurement In Tampa Bay, Removal From Sewage And Development Of An Estrogen Receptor Model, Monica Mion Cook

USF Tampa Graduate Theses and Dissertations

The significance of endocrine-disrupting compounds (EDCs) in the environment has only recently come to the forefront of scientific research, policy debates, water utilities management and public awareness. EDCs have the ability to interfere with the normal functioning of the endocrine system of humans and other animals. Numerous chemicals are included in the class of compounds known as EDCs, and exposure is widespread. These compounds are found in a variety of environmental matrices (e.g., marine and freshwater systems, sediment, soil), transported there primarily through sewage effluent discharge and recycling of sewage sludge for topical fertilizer use. This transport to the environment …

Assessment Of Public Health Risks Associated With Petrochemical Emissions Surrounding An Oil Refinery, Erin L. Pulster

USF Tampa Graduate Theses and Dissertations

Refinery operations have been associated with a wide variety of atmospheric emissions consisting of criteria air pollutants, volatile organic components, hazardous air pollutants as well as other pollutants. With approximately 100 oil refineries in the Wider Caribbean region (WCR), hydrocarbons in this region pose significant environmental and human health risks. One of the oldest and largest refineries in the WCR is the Isla Refineriá, which is located on the island of Curaçao, and has been the basis of historical debates and conflict between the public and the local government over the environmental and human health risks. This research aims to …

Comparison Of Isotope-Based Biomass Pathways With Groundfish Community Structure In The Eastern Gulf Of Mexico, Sheri Ann Huelster

USF Tampa Graduate Theses and Dissertations

This study compared traditional community analysis with stable-isotope trophic analysis to define process-based trophic elements of community structure in the eastern Gulf of Mexico, and developed a predictive capability regarding changes to fish community structure that would be expected from increasing eutrophication. Specifically, it used an existing trawl survey program (SEAMAP) to compare invertebrate herbivore (sponge and sea urchin) isotopes with groundfish isotopes, and then compared the resulting spatial patterns with spatial variation in community structure, as identified by cluster analysis. The comparison was applied to seven NMFS survey zones that extended offshore from the Caloosahatchee River, FL northwest to …

Tornado Fatalities: An In-Depth Look At Physical And Societal Influences, Heather Joann Key

USF Tampa Graduate Theses and Dissertations

The purpose of this study is to model and determine significant predictors of tornado death index values, and to investigate these significant predictors and what makes people vulnerable to tornado fatalities through expert interviews. This study also provides an understanding of the study participant’s perceptions of their county’s vulnerability to tornado fatality and demonstrates a true integration of methods and fields by studying geographic, meteorological, and sociological phenomena by use of quantitative and qualitative methods. The study consists of two parts: 1) A quantitative exploration of variables hypothesized to predict Tornado Death Index (TDI) values, 2) A qualitative investigation to …