Other Oceanography and Atmospheric Sciences and Meteorology Commons^™

Underwater Hearing In The Loggerhead Turtle (Caretta Caretta): A Comparison Of Behavioral And Auditory Evoked Potential Audiograms, Kelly Martin

USF Tampa Graduate Theses and Dissertations

Methods for collecting behavioral audiograms are often time consuming and require trained, captive subjects. It is more practical to measure hearing sensitivity using electrophysiological methods, such as auditory evoked potential (AEP) testing, in which electrodes measure action potentials in response to acoustic stimuli. These data can be collected in a matter of hours. However, results should be verified through behavioral testing. Current knowledge of marine turtle auditory abilities is based on a few electrophysiological tests. The purpose of this study was to collect and compare behavioral and auditory evoked potential audiograms in a captive adult loggerhead turtle (Caretta caretta …

Foraminiferal Assemblages On Sediment And Reef Rubble At Conch Reef, Florida Usa, Christy Michelle Stephenson

USF Tampa Graduate Theses and Dissertations

Benthic foraminiferal assemblages are widely used to interpret responses of the benthic communities to environmental stresses. This study compares epibiotic foraminiferal assemblages, collected from reef rubble, with those from reef sediments. The study site, Conch Reef, is the site of the Aquarius Underwater Habitat research facility and includes protected areas used only for scientific studies. Although a number of studies have enumerated foraminiferal taxa from the Florida reef tract, no projects have focused on the assemblages that occur at Conch Reef.

Sediment and reef rubbles samples were collected via SCUBA from a depth range of 13 to 26 m during …

Aspects Of The Life History Of The Snowy Grouper, Epinephelus Niveatus, In The Gulf Of Mexico, Kelley Kowal

USF Tampa Graduate Theses and Dissertations

Knowledge of many life history parameters are essential to properly assess and manage fish species. Although the snowy grouper, Epinephelus niveatus, is a commercially valuable fish, which is harvested throughout the Gulf of Mexico, little is known about its age, growth, and reproduction from this region. In this study, snowy grouper from the northern and eastern regions of the Gulf of Mexico were examined primarily using commercially-derived samples that were collected between 1984 and 2004. A total of 1,200 snowy grouper with fork lengths between 242 and 1,190 mm were collected. Sectioned saggital otoliths were used to determine the age …

Discovery Of Novel Viruses From Animals, Plants, And Insect Vectors Using Viral Metagenomics, Terry Fei Fan Ng

USF Tampa Graduate Theses and Dissertations

Understanding emerging viruses is critical for disease monitoring and prediction; however, surveys of novel viruses are hindered by the lack of a universal assay for viruses. Viral metagenomics, consisting of viral particle purification and shotgun sequencing, is a powerful technique for discovering viruses in a wide variety of sample types. However, current protocols are not effective on tissue samples (e.g., lungs, livers and tumors), where they are hindered by the high amount of host nucleic acids which limits the percentage of sequences that originate from viruses. In this dissertation, a modified viral metagenomics protocol was developed and utilized to effectively …

Linking Soil Loss To Sediment Delivery In Two Estuaries In Puerto Rico, Nekesha Bernadette Williams

USF Tampa Graduate Theses and Dissertations

Enhanced soil loss from the watershed is a major environmental issue. Increased soil loss from a watershed can potentially increase sediment delivery and loading to aquatic ecosystems such as rivers and estuaries. An increase in sediment delivery and loading to freshwater and transitional marine ecosystems can impact water quality and supply specifically by: (1) reducing water clarity, (2) transporting nutrient and pollutant laden sediments and (3) reducing the storage capacity of reservoirs. To address these broader environmental impacts of increased sediment delivery and loading to aquatic ecosystems it is imperative that potential source areas of sediments available for transport are …

Hf Radar Performance In A Low-Energy Environment: Codar Seasonde Experience On The West Florida Shelf, Yonggang Liu, Robert H. Weisberg, Clifford R. Merz, Sage Litchtenwalner, Gary J. Kirkpatrick

Yonggang Liu

Three long-range (5 MHz) Coastal Ocean Dynamics Application Radar (CODAR) SeaSonde HF radars overlooking an array of as many as eight moored acoustic Doppler current profilers (ADCPs) have operated on the West Florida Shelf since September 2003 for the purpose of observing the coastal ocean currents. HF radar performance on this low-energy (currents and waves) continental shelf is evaluated with respect to data returns, the rms differences between the HF radar and the ADCP radial currents, bearing offsets, and radial velocity uncertainties. Possible environmental factors affecting the HF radar performance are discussed, with the findings that both the low-energy sea …

West Florida Shelf Mean Circulation Observed With Long-Term Moorings, Robert H. Weisberg, Yonggang Liu, Dennis A. Mayer

Yonggang Liu

The mean circulation on the West Florida Continental Shelf is described using long-term current measurements. Bounded by the Florida peninsula to the east and the Gulf of Mexico to the west, the West Florida Continental Shelf mean flow is oriented approximately along-isobath and southward. The mean velocity vectors veer systematically with depth, shoreward over shallow water and seaward over deeper water. This polarization change implies that the mean flow is upwelling over shallow water and downwelling seaward from the inner shelf. Such a well-organized, three-dimensional coastal ocean circulation pattern, revealed by an unprecedented set of observations, and explained on the …

Patterns Of Upper Layer Circulation Variability In The South China Sea From Satellite Altimetry Using The Self-Organizing Map, Yonggang Liu, Robert H. Weisberg, Yaochu Yuan

Yonggang Liu

Patterns of the South China Sea (SCS) circulation variability are extracted from merged satellite altimetry data from October 1992 through August 2004 by using the self-organizing map (SOM). The annual cycle, seasonal and inter-annual variations of the SCS surface circulation are identified through the evolution of the characteristic circulation patterns. The annual cycle of the SCS gener- al circulation patterns is described as a change between two opposite basin-scale SW-NE oriented gyres embedded with eddies: low sea surface height anomaly (SSHA) (cyclonic) in winter and high SSHA (anticyclonic) in summer half year. The transition starts from July--August (January--February) with a …

Rectification Of The Bias In The Wavelet Power Spectrum, Yonggang Liu, X. San Liang, Robert H. Weisberg

Yonggang Liu

This paper addresses a bias problem in the estimate of wavelet power spectra for atmospheric and oceanic datasets. For a time series comprised of sine waves with the same amplitude at different frequencies the conventionally adopted wavelet method does not produce a spectrum with identical peaks, in contrast to a Fourier analysis. The wavelet power spectrum in this definition, that is, the transform coefficient squared (to within a constant factor), is equivalent to the integration of energy (in physical space) over the influence period (time scale) the series spans. Thus, a physically consistent definition of energy for the wavelet power …

Current Patterns On The West Florida Shelf From Joint Self-Organizing Map Analyses Of Hf Radar And Adcp Data, Yonggang Liu, Robert H. Weisberg, Lynn K. Shay

Yonggang Liu

To assess the spatial structures and temporal evolutions of distinct physical processes on the West Florida Shelf, patterns of ocean current variability are extracted from a joint HF radar and ADCP dataset acquired from August to September 2003 using Self-Organizing Map (SOM) analyses. Three separate ocean– atmosphere frequency bands are considered: semidiurnal, diurnal, and subtidal. The currents in the semidiurnal band are relatively homogeneous in space, barotropic, clockwise polarized, and have a neap-spring modulation consistent with semidiurnal tides. The currents in the diurnal band are less homogeneous, more baroclinic, and clockwise polarized, consistent with a combination of diurnal tides and …

Sea Surface Temperature Patterns On The West Florida Shelf Using Growing Hierarchical Self-Organizing Maps, Yonggang Liu, Robert H. Wesiberg, Ruoying He

Yonggang Liu

Neural network analyses based on the self-organizing map (SOM) and the growing hierarchical self-organizing map (GHSOM) are used to examine patterns of the sea surface temperature (SST) variability on the West Florida Shelf from time series of daily SST maps from 1998 to 2002. Four characteristic SST patterns are extracted in the first-layer GHSOM array: winter and summer season patterns, and two transitional patterns. Three of them are further expanded in the second layer, yielding more detailed structures in these seasons. The winter pattern is one of low SST, with isotherms aligned approximately along isobaths. The summer pattern is one …