Physical Sciences and Mathematics Commons^™

Sediment Transport And Distribution Over Continental Shelves: A Glimpse At Two Different River-Influenced Systems, The Cariaco Basin And The Amazon Shelf., Laura Lorenzoni

USF Tampa Graduate Theses and Dissertations

The aim of this dissertation was to understand lithogenic suspended sediment transport mechanisms and distribution in two river-influenced margins: The Cariaco Basin, Venezuela, and the Amazon Shelf, Brazil. Lithogenic sediment input in the Cariaco Basin is controlled by small mountainous rivers (SMR), while in the Amazon Shelf it is dominated by the Amazon River, the largest river in the world in terms of freshwater discharge (~20% of global riverine discharge). Optical transmissometer measurements were coupled with particulate organic matter (POM) observations to understand changes in the geochemical composition of suspended sediment and spatial/temporal distributions over the two regions of interest. …

Production Of Bioactive Secondary Metabolites By Florida Harmful Bloom Dinoflagellates Karenia Brevis And Pyrodinium Bahamense, Cheska Burleson

USF Tampa Graduate Theses and Dissertations

Despite the critical role algae serve as primary producers, increases or accumulation of certain algae may result in Harmful Algal Blooms (HABs). Algal toxins from these blooms contribute significantly to incidences of food borne illness, and evidence suggests HABs are expanding in frequency and distribution. Mitigation of these HABs without knowledge of the ecological purpose and biochemical regulation of their toxins is highly unlikely. The production, function, and potential of secondary metabolites produced by the dinoflagellates Karenia brevis and Pyrodinium bahamense, were investigated.

Brevetoxins were demonstrated by two different methods to localize within the cytosol of Karenia brevis. …

A Study Of The Eastern Oyster, Crassostrea Virginica, In Tampa Bay: Effects Of Perkinsus Marinus On Reproduction And Condition, Bridgit Melora Mccrickard

USF Tampa Graduate Theses and Dissertations

Abstract

Five sites in Tampa Bay, Florida, were sampled monthly from February 2006 to January 2007. These sites were located at the mouth of the Alafia River, in an inlet of Cross Bayou, on the easement of Gandy Bridge, near mangrove in Manatee County, and an inlet of Salt Creek, off Bayboro Harbor. Standard methods were used to determine shell height and Condition Index (CI). Intensity and prevalence of Perkinsus marinus were analyzed using Ray's Thioglycollate medium test, while Haplosporidium nelsoni was studied by histological examination. Histological methods were also used to determine sex ratios, reproductive phases, and egg diameters. …

Surface Mass Transfer In Large Eddy Simulation (Les) Of Langmuir Turbulence, Cigdem Akan

USF Tampa Graduate Theses and Dissertations

Over the past century the study of gas exchange rates between the atmosphere and the ocean has received increased attention because of concern about the fate of greenhouse gases such as CO₂ released into the atmosphere. Of interest is the oceanic uptake of CO₂ in shallow water coastal regions as biological productivity in these regions is on average about three times larger than in the open ocean. It is well-known that in the absence of breaking surface waves, the water side turbulence controls gas transfer of sparingly soluble gases such as CO₂ from the air to the …

Florida Fishery-Wide Reproductive Indices Of Stone Crab, Menippe Mercenaria, And Their Application To Stock Assessment And Management, Claire Elizabeth Crowley

USF Tampa Graduate Theses and Dissertations

The stone crab, Menippe mercenaria, supported the third most valuable fishery in Florida in 2016. Declining catch per unit effort (CPUE) and overall negative trend in landings since 2000 have raised concerns among fisherman, researchers, and fishery managers about the resiliency of the fishery. The Florida Fish and Wildlife Research Institute estimated that the Florida stone crab fishery has been overexploited since 1997. Overexploited fisheries, such as the commercial stone crab fishery, risk induced changes in life history parameters, such as age at maturation and reproductive output. In turn, these population-level changes have the potential to reduce the spawning …

The Impacts Of Population Density, And State & National Litter Prevention Programs On Marine Debris, Melissa Rose Brogle

USF Tampa Graduate Theses and Dissertations

Marine debris is improperly disposed of solid waste, also called litter, which is deposited in the marine environment (NOAA, 2010). Litter prevention techniques such as fines, cleanups, incentives, and others, can help to decrease litter, and ultimately decrease marine debris. This research analyzed 2000 and 2010 International Coastal Cleanup (ICC) data obtained from The Ocean Conservancy to ascertain whether certain litter prevention techniques did reduce amounts and types of marine debris found in coastal areas. The litter prevention techniques analyzed included state bottle bills, voluntary monofilament fishing line recycling programs, and the Keep America Beautiful (KAB) cigarette butt litter prevention …

Evidence For Viral Infection In The Copepods Labidocera Aestiva And Acartia Tonsa In Tampa Bay, Florida, Darren Stephenson Dunlap

USF Tampa Graduate Theses and Dissertations

Mesozooplankton are of critical importance to marine food webs by transferring energy from the microbial food web to higher trophic levels and depositing energy to the deeper ocean layers through fecal deposition. While decades of research have shown that viruses have significant impacts in the oceans, and infect a wide range of organisms from bacteria to whales, there is still little known about the impacts of viruses on the mesozooplankton community. As copepods are the most abundant mesozooplankton group, this study sought to characterize the viruses present in natural populations of the calanoid copepods Acartia tonsa and Labidocera aestiva in …

An Ecological Assessment Of A Juvenile Estuarine Sportfish, Common Snook (Centropomus Undecimalis), In A Tidal Tributary Of Tampa Bay, Florida, Adam Benjamin Brame

USF Tampa Graduate Theses and Dissertations

The common snook, Centropomus undecimalis, is an estuarine dependent sport fish that relies upon subtidal wetlands as nursery habitat. Despite the economic and recreational significance of this species, there are portions of its life history and biology that are poorly understood, particularly its early life history. Understanding juvenile snook use of wetland habitats is crucial given the rapid loss and degradation of these areas to anthropogenic impacts. Young-of-the-year snook were collected in pond and creek habitats of a single wetland system to assess early life ecology and habitat use. Proxies of habitat quality were used to determine which habitats …

A Ctd Biotag For Mid-Sized Marine Predators, Heather Broadbent

USF Tampa Graduate Theses and Dissertations

Biologging tools for investigating the study of fine-scale linkages between animal behavior and the physical microstructure of the marine habitat are technically limited by substantial size, high cost or low sensor resolution. However, recent advances in electronic technologies and process techniques present attractive alternatives to current tag designs. Motivated by the need for a low-cost, compact CTD biotag for medium-sized marine animals, the University of South Florida Center for Ocean Technology developed a multi-sensor biotag for quantitative measurements of ocean salinity. This dissertation describes the development and performance of a novel CTD biotag used for animal-borne measurements of the physical …

Comparison Of The X-Track Altimetry Estimated Currents With Moored Adcp And Hf Radar Observations On The West Florida Shelf, Yonggang Liu, Robert H. Weisberg, Stefano Vignudelli, Laurent Roblou, Clifford R. Merz

Yonggang Liu

The performance of coastal altimetry over a wide continental shelf is assessed using multiple-year ocean current observations by moored Acoustic Doppler Current Profilers (ADCP) and high-frequency (HF) radar on the West Florida Shelf. Across-track, surface geostrophic velocity anomalies, derived from the X-TRACK along-track sea level anomalies are compared with the near surface current vector components from moored ADCP observations at mid shelf. The altimeter-derived velocity anomalies are also directly compared with the HF radar surface current vector radial components that are aligned perpendicular to the satellite track. Preliminary results indicate the potential usefulness of the along-track altimetry data in contributing …

Seasonal Variability On The West Florida Shelf, Yonggang Liu, Robert H. Weisberg

Yonggang Liu

The seasonal variations of the West Florida Continental Shelf (WFS) circulation and sea level are described using observations of velocity from an array of moored acoustic Doppler current profilers and various ancillary data. With record lengths ranging from 3 years to over a decade, a robust seasonal cycle in velocity is found, which varies across the shelf in a dynamically sensible way. Over most of the inner shelf these seasonal variations are primarily in response to local forcing, through Ekman-geostrophic spin-up, as previously found for the synoptic scale variability. Thus the inner shelf circulation is predominantly upwelling favorable from fall …

Optical Detection And Classification Of Phytoplankton Taxa Through Spectral Analysis, Daniel Tyler Sensi

USF Tampa Graduate Theses and Dissertations

Phytoplankton serve as the bottom of the marine food web and therefore play an essential role in marine ecosystems. On the other hand, coastal phytoplankton communities can adversely affect the marine ecosystem and humans. A variety of techniques have been developed to measure and study phytoplankton, including in situ methods (e.g., flow cytometry) and laboratory methods (e.g., microscopic taxonomy). These provide accurate measurements of phytoplankton taxa and concentrations, yet they are limited in space and time, and synoptic information is difficult to obtain with these techniques.

Optical remote sensing may provide complementary information for its synoptic nature, as demonstrated by …

Occurrence, Toxicity, And Diversity Of Pseudo-Nitzschia In Florida Coastal Waters, Sheila O'Dea

USF Tampa Graduate Theses and Dissertations

Domoic acid (DA), a potent neurotoxin that has the potential to cause amnesic shellfish poisoning (ASP), is produced by members of the marine diatom genus Pseudo-nitzschia. Outbreaks of ASP in humans and of DA poisoning in birds and marine mammals have been reported across the United States and Canada since the late 1980's. Pseudo-nitzschia species can be extremely abundant in Florida waters, with densities often exceeding 10⁶ cells/L, and sometimes exceeding 10⁷ cells/L. Based on preliminary data, it is evident that at least nine species of Pseudo-nitzschia are found in Florida coastal waters. At least six of …

Micronekton And Macrozooplankton Of The Western Antarctic Peninsula And The Eastern Ross Sea: Contrast Between Two Different Thermal Regimes, Melanie Leigh Parker

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Micronekton and macrozooplankton were sampled from the Western Antarctic Peninsula (WAP) and eastern Ross Sea regions. Samples were collected over the course of six research cruises to the Southern Ocean. Four of those cruises were conducted in the Marguerite Bay region of the WAP during the austral fall and winter of 2001 and 2002. A fifth cruise sampled faunal assemblages at nine sites, ranging from Joinville Island at the northern tip of the WAP to Charcot Island near the southern extent of the WAP, during austral fall 2010. A sixth cruise was conducted in the pack ice within the …

On The Spatial And Temporal Variability Of Upwelling In The Southern Caribbean Sea And Its Influence On The Ecology Of Phytoplankton And Of The Spanish Sardine (Sardinella Aurita), Digna Tibisay Rueda-Roa

USF Tampa Graduate Theses and Dissertations

The Southern Caribbean Sea experiences a strong upwelling process along the coast from about 61°W to 75.5°W and 10-13°N. In this dissertation three aspects of this upwelling system are examined: (A) A mid-year secondary upwelling that was previously observed in the southeastern Caribbean Sea between June-July, when land based stations show a decrease in wind speed. The presence and effects of this upwelling along the whole southern Caribbean upwelling system were evaluated, as well as the relative forcing contribution of alongshore winds (Ekman Transport, ET) and wind-curl (Ekman Pumping, EP). (B) Stronger upwelling occurs in two particular regions, namely the …

Sea Surface Height: A Versatile Climate Variable For Investigations Of Decadal Change, Philip Robert Thompson

USF Tampa Graduate Theses and Dissertations

Decadal variations in climate are important, because the magnitude of sustained decadal change is often much larger than the often discussed background trends. Climate variability at interannual and longer periods is most often discussed in the context of climate modes defined by sea level pressure (SLP) and sea surface temperature (SST) patterns. However, SLP and SST are not capable descriptors of ocean dynamics. The approximately two decades of global sea surface height (SSH) measurements from satellite altimetry reveal substantial low-frequency redistributions of heat and salt in the ocean, which may or may not be related to defined climate modes. In …

Shelf-Scale Mapping Of Fish Distribution Using Active And Passive Acoustics, Carrie Christy Wall

USF Tampa Graduate Theses and Dissertations

Fish sound production has been associated with courtship and spawning behavior. Acoustic recordings of fish sounds can be used to identify distribution and behavior. Passive acoustic monitoring (PAM) can record large amounts of acoustic data in a specific area for days to years. These data can be collected in remote locations under potentially unsafe seas throughout a 24-hour period providing datasets unattainable using observer-based methods. However, the instruments must withstand the caustic ocean environment and be retrieved to obtain the recorded data. This can prove difficult due to the risk of PAMs being lost, stolen or damaged, especially in highly …

Thermal Determinants Of Nest Site Selection In Loggerhead Sea Turtles, Caretta Caretta, At Casey Key, Florida, Lindsey Nicole Flynn

USF Tampa Graduate Theses and Dissertations

Many environmental cues are thought to influence nest site selection by loggerhead sea turtles, Caretta caretta, and much debate exists over the possible influence of sand temperature. This study had two primary objectives: (1) to measure thermal differences across transects of a major nesting beach of Casey Key (28.7 N, 82.3 W), Florida and (2) to evaluate thermal pattern variation that influenced nesting patterns of adult female loggerhead sea turtles. A secondary objective of this study was to determine the efficacy of infrared thermometers to collect sand surface temperatures in the field.

Temperature data were collected from 145 nest …

Spatial And Temporal Variability Of Remotely Sensed Ocean Color Parameters In Coral Reef Regions, Daniel Brooks Otis

USF Tampa Graduate Theses and Dissertations

The variability of water-column absorption due to colored dissolved organic matter (CDOM) and phytoplankton in coral reef regions is the focus of this study. Hydrographic and CDOM absorption measurements made on the Bahamas Banks and in Exuma Sound during the spring of 1999 and 2000 showed that values of salinity and CDOM absorption at 440nm were higher on the banks (37.18 psu, 0.06 m^-1), compared to Exuma Sound (37.04 psu, 0.03 m^-1). Spatial patterns of CDOM absorption in Exuma Sound revealed that plumes of CDOM-rich water flow into Exuma Sound from the surrounding banks. To examine absorption variability in reef …

Responses To Chemical Exposure By Foraminifera: Distinguishing Dormancy From Mortality, Benjamin James Ross

USF Tampa Graduate Theses and Dissertations

The Deepwater Horizon blowout in 2010 released an estimated 4.9 million barrels of crude oil into the Gulf of Mexico in the 83 days between the initial explosion and the capping of the well. Response included extensive use of Corexit© oil dispersant. Although South Florida was spared exposure by currents, this event highlights the need for effective bioassay organisms for coral reefs. Amphistegina spp. are benthic foraminifers that host diatom symbionts in a relationship similar to that of coral and their zooxanthellae. Amphistegina spp. occur abundantly in reef communities nearly worldwide, are easily collected and maintained in culture, and are …

Impact Of Hono On Global Atmospheric Chemistry Calculated With An Empirical Parameterization In The Emac Model, Yasin F. Elshorbany, B. Steil, C. Bruehl, J. Lelieveld

USF St. Petersburg campus Faculty Publications

The photolysis of HONO is important for the atmospheric HOx (OH + HO2) radical budget and ozone formation, especially in polluted air. Nevertheless, owing to the incomplete knowledge of HONO sources, realistic HONO mechanisms have not yet been implemented in global models. We investigated measurement data sets from 15 field measurement campaigns conducted in different countries worldwide. It appears that the HONO/NOx ratio is a good proxy predictor for HONO mixing ratios under different atmospheric conditions. From the robust relationship between HONO and NOx, a representative mean HONO/NOx ratio of 0.02 has been derived. Using a global chemistry-climate model and …

Comparisons Of Observed And Modeled Oh And Ho2 Concentrations During The Ambient Measurement Period Of The Ho(X)Comp Field Campaign, Y. Kanaya, A. Hofzumahaus, H. -P. Dorn, T. Brauers, H. Fuchs, F. Holland

USF St. Petersburg campus Faculty Publications

A photochemical box model constrained by ancillary observations was used to simulate OH and HO2 concentrations for three days of ambient observations during the HO(x)Comp field campaign held in Julich, Germany in July 2005. Daytime OH levels observed by four instruments were fairly well reproduced to within 33% by a base model run (Regional Atmospheric Chemistry Mechanism with updated isoprene chemistry adapted from Master Chemical Mechanism ver. 3.1) with high R-2 values (0.72-0.97) over a range of isoprene (0.3-2 ppb) and NO (0.1-10 ppb) mixing ratios. Daytime HO2(*) levels, reconstructed from the base model results taking into account the sensitivity …

Mangroves, Mudbanks And Seawalls: Political Ecology Of Adaptation To Sea Level Rise In Suriname, Ravic Nijbroek

USF Tampa Graduate Theses and Dissertations

This study seeks to understand how global discourses of sea level rise (SLR) and mangrove ecology influence national climate change adaptation policy to reduce coastal vulnerability in Suriname. A majority of the Surinamese population lives along the low elevation coastal zone and is highly exposed to projected SLR. Failure by the international community to reach agreement on climate change mitigation means that vulnerable coastal communities must adapt. The Suriname coast is predominantly shaped by mudbanks and mangroves which together provide protection against coastal erosion and trap sediments resulting in coastal accretion. Knowledge claims of mangrove ecology and utility in SLR …