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Quantitative Assessment Of The Trophic Ecology Of The Oceanic Ctenophore, Bolinopsis Infundibulum, In Monterey Bay, California, Victoria C. Scriven

USF Tampa Graduate Theses and Dissertations

Bolinopsis infundibulum is a wide-ranging, ubiquitous ctenophore whose fragile nature makes the collection of specimens and quantification of key predator-prey activities in controlled laboratory experiments, challenging. Thus, in situ methods often represent the best means for data collection. However, while present in surface waters, these animals can also be abundant at depths well beyond those attainable by divers. As a result, very little empirical data exist over the depth range of their natural habitats which limits our ability to assess key predator-prey interactions needed to assess their ecological role in midwater food webs. Working in Monterey Bay, California, remotely operated …

Global Economic Costs Of Aquatic Invasive Alien Species, Ross N. Cuthbert, Zarah Pattison, Nigel G. Taylor, Laura Verbrugge, Christophe Diagne, Danish A. Ahmed, Boris Leroy, Elena Angulo, Elizabeta Briski, César Capinha, Jane A. Catford, Tatenda Dalu, Franz Essl, Rodolphe E. Gozlan, Phillip J. Haubrock, Melina Kourantidou, Andrew M. Kramer, David Renault, Ryan J. Wasserman, Franck Courchamp

Integrative Biology Faculty and Staff Publications

Much research effort has been invested in understanding ecological impacts of invasive alien species (IAS) across ecosystems and taxonomic groups, but empirical studies about economic effects lack synthesis. Using a comprehensive global database, we determine patterns and trends in economic costs of aquatic IAS by examining: (i) the distribution of these costs across taxa, geographic regions and cost types; (ii) the temporal dynamics of global costs; and (iii) knowledge gaps, especially compared to terrestrial IAS. Based on the costs recorded from the existing literature, the global cost of aquatic IAS conservatively summed to US$345 …

Strength Restoration Of Corrosion Damaged Piles Repaired With Carbon Fiber Reinforced Polymer Systems, Jethro Clarke

USF Tampa Graduate Theses and Dissertations

Of the 12,741 bridges accounted for by the Florida Department of Transportation (FDOT), approximately 50% were built between the 1950s and 1960s. During this period, bridges were typically constructed in coastal environments using pile bents. Now, the main threat to bridges in these environments is corrosion, which occurs in the splash zones of most bridge piles. These zones contain high concentrations of chlorides, oxygen and moisture, the corner stones of a highly corrosive environment. Corrosion compromises steel reinforcement in these areas leading to cracking, spalling and an inevitable loss of capacity.

In recent years, significant strides have been made in …

Iron-Virus Interactions: Development And Testing Of The Ferrojan Horse Hypothesis, Chelsea Bonnain

USF Tampa Graduate Theses and Dissertations

Iron is an essential micronutrient for phytoplankton metabolism that limits growth in many regions of the surface ocean. More than 99.9% of oceanic dissolved iron is organically complexed to an iron-binding ligand, many of which have yet to be characterized. This thesis puts forth the Ferrojan Horse Hypothesis, which predicts a role for marine phages in oceanic iron cycling. Based on evidence from non-marine model systems, the Ferrojan Horse Hypothesis suggests that some marine phages (short for bacteriophages, or viruses that infect bacteria) can use iron as a “Trojan Horse” to gain access to host siderophore-bound iron receptors for infection. …

The Ferrojan Horse Hypothesis: Iron-Virus Interactions In The Ocean, Chelsea Bonnain, Mya Breitbart, Kristen N. Buck

Marine Science Faculty Publications

Iron is an essential nutrient and the sub-nanomolar concentrations of iron in open ocean surface waters are often insufficient to support optimal biological activity. More than 99.9% of dissolved iron in these waters is bound to organic ligands, yet determining the identity of these ligands in seawater remains a major challenge. Among the potential dissolved organic ligands in the colloidal fraction captured between a 0.02 and a 0.2 μm filter persists an extremely abundant biological candidate: viruses, most of which are phages (viruses that infect bacteria). Recent work in non-marine model systems has revealed the presence of iron ions within …

A Comparative Analysis Of Portable X-Ray Fluorescence Spectrometry And Stable Isotopes In Assessing Ancient Coastal Peruvian Diets, Theresa Jane Gilbertson

USF Tampa Graduate Theses and Dissertations

This dissertation explores a cross-cultural analysis of the dietary signatures of four coastal cultures of prehistoric Peru. A combination of elemental analysis based on portable x-ray fluorescence spectrometry (pXRF), testing trace elements presented in 209 individuals’ skulls representing the Nazca (38), Cañete (33), Lima (40), and Moche (98) valleys and/or cultures of the first millennium AD, is weighed in conjunction with isotope ratio mass spectrometry (IRMS) to analyze human bone collagen and bone apatite derived from a portion of the individuals represented in the Nazca, Cañete, and Lima cranial samples.

Evidence from the results of both tests are weighed using …

Corrosion Of Steel In Submerged Concrete Structures, Michael Thomas Walsh

USF Tampa Graduate Theses and Dissertations

This investigation determined that severe corrosion of steel can occur in the submerged portions of reinforced concrete structures in marine environments. Field studies of decommissioned pilings from actual bridges revealed multiple instances of strong corrosion localization, showing appreciable local loss of steel cross-section. Quantitative understanding of the phenomenon and its causes was developed and articulated in the form of a predictive model. The predictive model output was consistent with both the corrosion rate estimates and the extent of corrosion localization observed in the field observations. The most likely explanation for the observed phenomena that emerged from the understanding and modeling …

Discovery, Prevalence, And Persistence Of Novel Circular Single-Stranded Dna Viruses In The Ctenophores Mnemiopsis Leidyi And Beroe Ovata, Mya Breitbart, Bayleigh Benner, Parker Jernigan, Karyna Rosario, Laura Birsa, Rachel Harbeitner, Sidney Fulford, Carina Graham, Anna Walters, Dawn Goldsmith, Stella Berger, Jens Nejstgaard

Marine Science Faculty Publications

Gelatinous zooplankton, such as ctenophores and jellyfish, are important components of marine and brackish ecosystems and play critical roles in aquatic biogeochemistry. As voracious predators of plankton, ctenophores have key positions in aquatic food webs and are often successful invaders when introduced to new areas. Gelatinous zooplankton have strong impacts on ecosystem services, particularly in coastal environments. However, little is known about the factors responsible for regulating population dynamics of gelatinous organisms, including biological interactions that may contribute to bloom demise. Ctenophores are known to contain specific bacterial communities and a variety of invertebrate parasites and symbionts; however, no previous …

Water Column Stratification Structures Viral Community Composition In The Sargasso Sea, Dawn Goldsmith, Jennifer Brum, Max Hopkins, Craig Carlson, Mya Breitbart

Marine Science Faculty Publications

A decade-long study of viral abundance at the Bermuda Atlantic Time-series Study (BATS) site recently revealed an annually recurring pattern where viral abundance was fairly uniform in the well-mixed upper water column each winter, yet a subsurface peak in viral abundance between 60 and 100 m depth developed each summer during water column stratification (Parsons et al. 2012; ISME J 6:273–284). Building upon these findings, this study tests the hypothesis that in the well-mixed period (March), the viral communities at the surface and at 100 m depth are similar in composition, while during water column stratification (September), differences in the …

Forecasting Corrosion Of Steel In Concrete Introducing Chloride Threshold Dependence On Steel Potential, Andrea Nathalie Sanchez

USF Tampa Graduate Theses and Dissertations

Corrosion initiates in reinforced concrete structures exposed to marine environments when the chloride ion concentration at the surface of an embedded steel reinforcing bar exceeds the chloride corrosion threshold (CT) value. The value of CT is generally assumed to have a conservative fixed value ranging from 0.2% to - 0.5 % of chloride ions by weight of cement. However, extensive experimental investigations confirmed that CT is not a fixed value and that the value of CT depends on many variables. Among those, the potential of passive steel embedded in concrete is a key influential factor on the value of CT …

Investigations For Utilizing Pteropods As Bioindicators Of Environmental Change Along The Western Antarctic Peninsula, Paul Mark Suprenand

USF Tampa Graduate Theses and Dissertations

Pteropods are holoplanktonic gastropod molluscs found globally. Although species diversity is greater at lower latitudes, species abundance is greater at temperate and polar latitudes. Declines in pteropod populations have not only been correlated to declines of their major predators, but pteropods have also been used as bioindicators of global environmental changes such as ocean acidification. With high latitude abundances, pteropods provide significant sustenance for species such as the Atlantic salmon in the Atlantic Ocean and Pleuragramma antarcticum in the Southern Ocean. Because pteropods eat phytoplankton and other pteropods, factors that affect pteropod abundance influence many trophic levels. This dissertation explores …

Biogeochemical Cycling Of Arsenic In The Marine Shallow-Water Hydrothermal System Of Tutum Bay, Ambitle Island, Papua New Guinea, Roy E. Price

USF Tampa Graduate Theses and Dissertations

The marine shallow-water hydrothermal vent system of Tutum Bay, Ambitle Island, PNG discharges hot, acidic, arsenic-rich, chemically reduced fluid into cool, alkaline, oxygenated seawater. Gradients in temperature, pH, total arsenic (TAs) and arsenic species, among others, are established as the two aqueous phases mix.

Hydrous ferric oxides (HFO) are precipitated around focused venting, and coat the surrounding sediments visibly to 150 m away. HFO coatings, mechanical transport and weathering of volcanoclastic sediments, as well as dissolution of carbonate sediments nearer to venting, combine to alter sediment chemistry substantially.

Tutum Bay surface sediments have a mean As concentration of 527 mg/kg. …

Molecular And Genomic Studies Of Temperate Phages From Halomonas Aquamarina And Bacillus Spp. Isolates From The Gulf Of Mexico, Jennifer M. Mobberley

USF Tampa Graduate Theses and Dissertations

Viruses are the most abundant biological entities in the ocean and are believed to contribute to nutrient cycling, bacterial diversity, and horizontal gene exchange. However, little is known about the relationship between temperate phages and their hosts in marine environments. In this thesis, phage-host systems from the Gulf of Mexico were used to study the influence of temperate phages in bacteria. PhiHAP-1 is a temperate myovirus induced with mitomycin C from Halomonas aquamarina isolate. The genome of this phage was 39,245 nucleotides long and contained 46 predicted genes. Besides genes involved in lysogeny, PhiHAP-1 contained a protelomerase, which is responsible …

Detection Of Pathogenic Bacteria And Fecal Enterococci In Recreational Water With An Evanescent Wave Fiber Optic Biosensor, Maria Theresa Trindade

USF Tampa Graduate Theses and Dissertations

Development of a rapid method for the detection of fecal enterococci and pathogenic microorganisms in beach water was attempted utilizing an evanescent wave fiber optic biosensor. Various assay formats including a sandwich immunoassay were tested in the development of a rapid assay. Fluorophore labeled antibodies were used for specific detection of bacteria captured or adsorbed directly to the surface of a polystyrene fiber optic waveguide. Binding of the fluorescent labeled antibody to its specific target or binding of a fluorescent labeled anti-IgG within 100-1000 nm of the waveguide surface caused excitation of the fluorescent conjugate resulting in a quantifiable signal. …