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Full-Text Articles in Physical Sciences and Mathematics

The Nitrogen Dynamics Of Deer Cave, Sarawak, And The Role Of Bat Caves As Biogeochemical Sinks In Tropical Moist Forests., Joyce Lundberg, Donald A. Mcfarlane, Guy Van Rentergem Nov 2022

The Nitrogen Dynamics Of Deer Cave, Sarawak, And The Role Of Bat Caves As Biogeochemical Sinks In Tropical Moist Forests., Joyce Lundberg, Donald A. Mcfarlane, Guy Van Rentergem

International Journal of Speleology

A better understanding of the role of bat caves as nitrogen sinks in tropical moist forest ecosystems can be expected to shed light on regional and spatial variability in nutrient recycling studies. We measured the nitrogen flux (in air and water) associated with a very large Chaerephon plicata bat colony in Deer Cave, Borneo, in the process generating a new, quantitative, estimate of the total bat population (774,828 ±48,320), and the first detailed modelling of an ammonia plume in a cave. Long-term storage of N does not occur in this wet cave. Our final budget numbers indicate that, of the …


Using Fine-Scale Aquatic Habitat Data To Construct Dreissenid Sdms In The Laurentian Great Lakes, Grace C. Henderson Mar 2022

Using Fine-Scale Aquatic Habitat Data To Construct Dreissenid Sdms In The Laurentian Great Lakes, Grace C. Henderson

USF Tampa Graduate Theses and Dissertations

The invasion of the Laurentian Great Lakes by aquatic invasive species (AIS) has been the subject of investigation for decades, due to their dramatic alterations to the ecosystem and high economic costs. Two AIS with the largest impacts are dreissenid zebra and quagga mussels, and though these species have been studied extensively, questions remain about what factors control their distributions, and whether lake warming will alter these distributions. Species distribution models (SDMs) offer a powerful tool to examine the relationship between species presences and environmental variables, which are typically bioclimactic data. The creation of the Aquatic Habitat (AqHab) dataset containing …


Quantitative Assessment Of The Trophic Ecology Of The Oceanic Ctenophore, Bolinopsis Infundibulum, In Monterey Bay, California, Victoria C. Scriven Mar 2022

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 …


Machine Learning For Species Habitat Analysis, Abigail Lavallin Nov 2021

Machine Learning For Species Habitat Analysis, Abigail Lavallin

USF Tampa Graduate Theses and Dissertations

Management and conservation initiatives will always be controlled by finite resources, whether financialor temporal. Understanding a species’ spatial ecology, and how its requirements vary across habitats and locations is key to a successful species management plan. During recent decades, it has been noted how many species populations have declined, despite conservation practices working to increase their numbers. The most prevalent impacts affecting fauna populations have come from anthropogenic change in the form of habitat loss and destruction, along with fragmentation, and global climate change. There is a clear need for management practices to now operate on an entire landscape instead …


Do Different Relevance Attributes Indicate The Same Conservation Priorities? A Case Study In Caves Of Southeastern Brazil, Maysa F.V.R. Souza, Denizar A. Alvarenga, Marconi Souza-Silva, Rodrigo L. Ferreira Jul 2021

Do Different Relevance Attributes Indicate The Same Conservation Priorities? A Case Study In Caves Of Southeastern Brazil, Maysa F.V.R. Souza, Denizar A. Alvarenga, Marconi Souza-Silva, Rodrigo L. Ferreira

International Journal of Speleology

In the last decade, the scientific community brought to the debate gaps that slow down the advance of knowledge regarding global biodiversity. More recently, this discussion has reached subterranean environments, where these gaps are even more dramatic due to the relict and vulnerable nature of their species. In this context, we tested ecological metrics related to some of these gaps, checking if the biological relevance of the caves would change depending on ecological attributes related to each metric. The study was carried out in caves from southeastern Brazil, located in a region presenting a high richness of troglobitic species restricted …


Shorebird Response To Human-Induced Changes At Three Pinellas County Beaches, Rebecca J. Ruthberg-Campagna Mar 2021

Shorebird Response To Human-Induced Changes At Three Pinellas County Beaches, Rebecca J. Ruthberg-Campagna

USF Tampa Graduate Theses and Dissertations

Worldwide, shorebird habitat is being destroyed and degraded by development and sea level rise. Shorebirds depend on availability of pristine, undisturbed coastal habitats for resting and feeding during migration as well as for reproduction. Migratory shorebirds using the East Atlantic Flyway visit the Gulf of Mexico Beaches of Pinellas County, Florida as a stopover site during Fall and Spring migration. In addition to hosting migratory species, Pinellas County beaches are home to several year-round resident species that breed during Summer. Pinellas County is the most densely populated county in Florida, and its Gulf Coast is heavily developed with commercial and …


Modeling Early Life: Ontogenetic Growth And Behavior Affect Population Connectivity In Gulf Of Mexico Marine Fish, Kelly Vasbinder Nov 2020

Modeling Early Life: Ontogenetic Growth And Behavior Affect Population Connectivity In Gulf Of Mexico Marine Fish, Kelly Vasbinder

USF Tampa Graduate Theses and Dissertations

This dissertation is an examination of growth, behavior, and dispersal during the early life stages of marine fishes in the Gulf of Mexico. Understanding movements of early life stages is a key part of managing exploited fish populations. Position in the water column can impact larval dispersal, since it determines those currents to which larvae are exposed. First, I investigated the relationship between length and age in early life stages of marine fishes. I found that demersal fish taxa tend to be represented by exponential models, while pelagic fish tend to be represented by linear models. I suggest this may …


Biogeochemical Cycling Of Nutrients And Carbon In Subtropical Wetlands, Lauren N. Griffiths Jun 2020

Biogeochemical Cycling Of Nutrients And Carbon In Subtropical Wetlands, Lauren N. Griffiths

USF Tampa Graduate Theses and Dissertations

As human development intensifies, ecosystems around the word are being exponentially destroyed and degraded. Wetlands have the capacity to mitigate some of the possible problems by retaining nutrients and carbon, keeping them from harming downstream ecosystems or being released into the atmosphere. This project focuses on the processes that make wetlands successful by studying two unique ecosystems: 1) a created urban stormwater treatment wetland and 2) mangrove wetlands in Florida and Puerto Rico that were affected by hurricanes in 2017.

The first phase of this study investigates the role of sedimentation and vegetative and algal uptake of nutrients to retain …


The Ecology And Conservation Of An Urban Karst Subterranean Estuary, Robert J. Scharping Mar 2020

The Ecology And Conservation Of An Urban Karst Subterranean Estuary, Robert J. Scharping

USF Tampa Graduate Theses and Dissertations

Sulphur Springs is an artesian spring and part of the limestone karst topography of metropolitan Tampa, Florida, USA. Underlying this spring is an extensive cave system that hosts saltwater vents and conspicuous microbial biofilm communities. For decades, water from Sulphur Springs has been extracted and used to supplement public water supply and dry season flows in the Hillsborough River Estuary. This dissertation describes research conducted at Sulphur Springs to determine the impacts of urban land use on the underlying cave and downstream estuary ecosystems, and presents the use of this system as a model to fill certain ecological knowledge gaps. …


Isotope-Based Methods For Evaluating Fish Trophic Geographies, Julie L. Vecchio Feb 2020

Isotope-Based Methods For Evaluating Fish Trophic Geographies, Julie L. Vecchio

USF Tampa Graduate Theses and Dissertations

Data on the movement and diets of fish during a variety of life stages are important inputs to fisheries stock assessments and marine ecosystem models. Stable isotopes may provide previously inaccessible information on movement and diet of a variety of managed and forage fish species. Here I used several novel means of interpretation for stable isotope data to infer diets and movements of several important fisheries species over both short (weeks to months) and long (lifetime) timescales. To calculate a constant partitioning offset (CPO) between the δ15N of muscle and of liver tissue, I conducted a literature search …


The Peculiar Nature Of Florida’S Sandhill Wetlands, Ponds & Lakes— Their Ecohydrology, Relationship With The Regional Aquifer & Importance Within The Landscape., Renae Starr Nowicki Nov 2019

The Peculiar Nature Of Florida’S Sandhill Wetlands, Ponds & Lakes— Their Ecohydrology, Relationship With The Regional Aquifer & Importance Within The Landscape., Renae Starr Nowicki

USF Tampa Graduate Theses and Dissertations

This dissertation explores the ecohydrology of Florida’s peculiar and poorly studied sandhill wetland and water features, particularly those located in west-central Florida. The primary research goals include: compilation and summarization of the available ecohydrologic information for features across Florida; comparison of water level and water geochemistry data between sandhill wetlands and waters and the regional aquifer to provide evidence of regional hydrologic control; and use of geophysical applications to examine the hydraulic connections between sandhill wetlands and waters and the regional aquifer.

From this research, a natural history of sandhill wetland and water ecohydrology is presented, highlighting: the differences between …


Untapped Potential Of Gorgonian Octocorals For Detecting Environmental Change In Biscayne National Park, Florida, Usa, Selena A. Kupfner Johnson Nov 2019

Untapped Potential Of Gorgonian Octocorals For Detecting Environmental Change In Biscayne National Park, Florida, Usa, Selena A. Kupfner Johnson

USF Tampa Graduate Theses and Dissertations

One consequence of dramatic stony-coral loss has been recognition that gorgonian octocorals (Anthozoa: Octocorallia) have emerged among the dominant reef fauna. However, gorgonians are notoriously difficult to field-identify and consequently have been underrepresented in most monitoring efforts resulting in a lack of long-term data. The rich diversity of habitats, close proximity to the urban center of Miami, and connectivity to other areas of Florida have made Biscayne National Park an active location for reef research since its establishment in 1968. As such, a plethora of data (e.g., museum specimen and species abundance data) has been collected and stored in archives …


Design And Implementation Of Degenerate Qpcr/Qrt-Pcr Primers To Detect Microbial Nitrogen Metabolism In Wastewater And Wastewater-Related Samples, Ryan F. Keeley Aug 2019

Design And Implementation Of Degenerate Qpcr/Qrt-Pcr Primers To Detect Microbial Nitrogen Metabolism In Wastewater And Wastewater-Related Samples, Ryan F. Keeley

USF Tampa Graduate Theses and Dissertations

Nitrogen cycling processes can be tracked using quantitative Polymerase Chain Reaction (qPCR) to determine the presence and qReverse Transcriptase-PCR (qRT-PCR) to determine expression of key genes, or ‘biological markers’, for nitrogen metabolism. Nitrification is catalyzed in part, by two enzymes: ammonia monooxygenase (AMO; NH3 NH2OH) and nitrite oxidoreductase (NXR; NO2- NO3-). For denitrification, four enzymes act sequentially: nitrate reductase (NAR/NAP; NO3- NO2-), nitrite reductase (NIR; NO2- NO), nitric oxide reductase (NOR; NO  N2O), and nitrous oxide reductase (NOS; N2O  N2). A principle of wastewater treatment (WWT) is to remove excess nitrogen by taking advantage of natural nitrogen cycling …


Stable Isotope Geochemistry Of Shelled Marine Invertebrates: Wide-Ranging Applications, Nasser M. Al-Qattan Jul 2019

Stable Isotope Geochemistry Of Shelled Marine Invertebrates: Wide-Ranging Applications, Nasser M. Al-Qattan

USF Tampa Graduate Theses and Dissertations

Mollusks grow by adding discrete growth layers throughout their lifetime (i.e., accretion). More specifically, most marine mollusks precipitate their shells in oxygen isotopic equilibrium with seawater or with a constant offset from equilibrium. The stable oxygen isotope values (δ18O) of their shells are determined by the temperature and δ18O values of the surrounding water during calcification without significant vital effects. In comparison, the stable carbon isotope values (δ13C) of their shells reflect those of the dissolved inorganic carbon (δ13C- DIC) and respired carbon dioxide. Therefore, variations in the oxygen and carbon isotope …


Habitat Suitability Index Model Of The Florida Sandhill Crane (Grus Canadensis Pratensis) In West-Central Florida, Courtney E. Buck Jun 2019

Habitat Suitability Index Model Of The Florida Sandhill Crane (Grus Canadensis Pratensis) In West-Central Florida, Courtney E. Buck

USF Tampa Graduate Theses and Dissertations

The Florida Sandhill Crane (Grus canadensis pratensis) is a state threatened endemic subspecies of the Sandhill Crane (Nesbitt & Tacha, 1997). With a population that was estimated at a maximum of 5,000 individuals in 2003 (Nesbitt & Hatchitt, 2008), it is imperative to identify potentially viable habitats, as Florida is rapidly developing. This research develops a Habitat Suitability Index model to determine unsuitable to optimally suitable habitat locations throughout west-central Florida. To do so, six suitability variables based on the crane’s life history were evaluated: Potential nesting area, immediate nesting area, wetland coverage, foraging area, brooding area, and road proximity. …


Documenting Evolution: Comparing And Contrasting Late Mesozoic And Late Cenozoic Molluscan Patterns, Joshua Slattery Apr 2019

Documenting Evolution: Comparing And Contrasting Late Mesozoic And Late Cenozoic Molluscan Patterns, Joshua Slattery

USF Tampa Graduate Theses and Dissertations

Despite major advances, evolutionary theory still has numerous shortcomings in terms of fully understanding the controls on speciation and diversification. A major factor limiting our knowledge is how biology and paleobiology view speciation from separate micro- and macro-evolutionary perspectives, respectively. Biologists typically examine microevolutionary changes within species from various biogeographic, behavioral, morphological, and genetic perspectives, which contrasts to the macroevolutionary approach of most paleobiologists, who have examined the same phenomena at larger scales but with the standpoint of time, have also concentrated on aspects of global or regional diversification (e.g., richness, origination rates, and extinction rates) over the long-term. Noticeably …


Integrating Towed Underwater Video With Multibeam Acoustics For Mapping Benthic Habitat And Assessing Reef Fish Communities On The West Florida Shelf, Alexander Ross Ilich Nov 2018

Integrating Towed Underwater Video With Multibeam Acoustics For Mapping Benthic Habitat And Assessing Reef Fish Communities On The West Florida Shelf, Alexander Ross Ilich

USF Tampa Graduate Theses and Dissertations

Using a towed underwater video camera system, benthic habitats were classified along transects in a popular offshore fishing area on the West Florida Shelf (WFS) known as “The Elbow.” Additionally, high resolution multibeam bathymetry and co-registered backscatter data were collected for the entire study area. Using these data, full coverage geologic and biotic habitat maps were developed using both unsupervised and supervised statistical classification methodologies. The unsupervised methodology used was k-means clustering, and the supervised methodology used a random forest algorithm. The two methods produced broadly similar results; however, the supervised methodology outperformed the unsupervised methodology. The results of the …


Old And Recent Processes In A Warm And Humid Desert Hypogene Cave: ‘A’Rak Na‘Asane, Israel, Amos Frumkin, Shlomi Aharon, Uri Davidovich, Boaz Langford, Yoav Negev, Micka Ullman, Anton Vaks, Shemesh Ya‘Aran, Boaz Zissu Jul 2018

Old And Recent Processes In A Warm And Humid Desert Hypogene Cave: ‘A’Rak Na‘Asane, Israel, Amos Frumkin, Shlomi Aharon, Uri Davidovich, Boaz Langford, Yoav Negev, Micka Ullman, Anton Vaks, Shemesh Ya‘Aran, Boaz Zissu

International Journal of Speleology

Recent environmental processes are studied in ʻA’rak Naʻasane Cave at the northern Judean Desert, Israel. The outer zone of the cave is heavily influenced by the outside environment through a large entrance, facilitating entry of air flow, fauna and humans, with minor cave-forming modifications. Conversely, the inner cave sustains humid and warm conditions, favoring modifications by condensation corrosion of convective air flow, associated with deposition of popcorn speleothems at the lower parts of dissolution pockets. The warm humid air of the inner cave may be associated with an underlying thermal water table. Active condensation corrosion is decreasing, possibly because of …


The Association Of Size Variation In The Dental Arch To Third Molar Agenesis For A Modern Population, Devin N. Williams Apr 2018

The Association Of Size Variation In The Dental Arch To Third Molar Agenesis For A Modern Population, Devin N. Williams

USF Tampa Graduate Theses and Dissertations

The frequency with which individuals do not develop their third molars, or wisdom teeth, is increasing worldwide. This current topic of human evolution is relevant to the research of anthropologists, geneticists, dentists, and other researchers involved in the study of human dentition. Many explanations have been offered to account for the prevalence of molar agenesis including, evolutionary, environmental, and genetic theories. The purpose of this research project is to determine the frequency of third molar agenesis and investigate the relationship between third molar agenesis and maxillomandibular jaw dimensions in a sample of orthodontic patients. This research tests the hypotheses that: …


Remote Sensing And Spatial Metrics For Quantifying Seagrass Landscape Changes: A Study On The 2011 Indian River Lagoon Florida Seagrass Die-Off Event, René Dieter Baumstark Mar 2018

Remote Sensing And Spatial Metrics For Quantifying Seagrass Landscape Changes: A Study On The 2011 Indian River Lagoon Florida Seagrass Die-Off Event, René Dieter Baumstark

USF Tampa Graduate Theses and Dissertations

Florida’s seagrasses are ecologically important marine environments which have suffered major degradation caused by increasing anthropogenic pressures. A 2011 seagrass die-off event caused by an algal bloom in the Florida Indian River Lagoon (IRL) was particularly severe with a majority of seagrass lost in areas such as the Banana River. An understanding of how this coastal marine environment changed is an important step toward better managing resources for conservation. Modern tools and methods provide new opportunities to study these changes at the landscape scale, a scale that informs on the larger more comprehensive state of a system. Classified satellite imagery …


The Blurred Line Between Photic And Aphotic Environments: A Large Mexican Cave With Almost No Dark Zone, Luis M. Mejía-Ortíz, Tanja Pipan, David C. Culver, Peter Sprouse Dec 2017

The Blurred Line Between Photic And Aphotic Environments: A Large Mexican Cave With Almost No Dark Zone, Luis M. Mejía-Ortíz, Tanja Pipan, David C. Culver, Peter Sprouse

International Journal of Speleology

Sistema Muévelo Rico is a 1.2 km long cave in Quintana Roo, less than 2 km from the Caribbean Sea. We measured illuminance to a level of 0.1 lux, organic matter (weight loss on ignition), temperature, and relative humidity. The last two were measured at hourly intervals for nearly one year. Approximately one-third of the cave has illuminance values greater than 0.01 lux, and most of the rest of the cave has light as well. Temperature and relative humidity were relatively constant, but they showed a daily cycle at all stations, albeit with different strengths. Organic matter averaged 8%, intermediate …


Reef Fish Biodiversity In The Florida Keys National Marine Sanctuary, Megan E. Hepner Nov 2017

Reef Fish Biodiversity In The Florida Keys National Marine Sanctuary, Megan E. Hepner

USF Tampa Graduate Theses and Dissertations

The biological diversity of reef-fish in the Florida Keys National Marine Sanctuary (FKNMS) from 1999 – 2016 was evaluated in terms of abundance, biomass, species richness, evenness, Shannon diversity, Simpson diversity, and functional diversity, using observations collected by multiple agencies and institutions under the Reef Visual Census (RVC) program. To compare the different diversity indices species richness, Shannon diversity, Simpson diversity, and functional diversity were converted into effective number of species. I examined the seven indices by no-take marine zones, in seven benthic habitat strata, and across the three-distinct geographic subregions in the Florida Keys domain (Upper, Middle, and Lower …


Spatial And Temporal Variation In Mangrove Distribution (1950-2014) In Tampa, Florida Usa, Carolyn Cheatham Rhodes Jun 2017

Spatial And Temporal Variation In Mangrove Distribution (1950-2014) In Tampa, Florida Usa, Carolyn Cheatham Rhodes

USF Tampa Graduate Theses and Dissertations

I carried out an observational study of historic high resolution aerial imagery spanning six decades (1950-2014) to identify recent and historic spatial extent of mangrove forests, within the municipal boundaries of the City of Tampa, Florida USA. My objectives were to map mangrove distribution and spatial extent and any change or patterns of change discernable. I observed variable patterns of change and rates of expansion varied between sites spatially as well as within sites between time intervals. I found notable changes in mangrove extent in the Tampa from historic and modern aerial imagery for the ~64-year period between 1950 and …


Abundance And Habitat Preferences Of Introduced Muscovy Ducks (Cairina Moschata), Jacqueline Marie Perry Cahanin Mar 2017

Abundance And Habitat Preferences Of Introduced Muscovy Ducks (Cairina Moschata), Jacqueline Marie Perry Cahanin

USF Tampa Graduate Theses and Dissertations

Muscovy ducks are native only to Central and South America, Mexico, and parts of southern Texas and are considered invasive in some areas outside of their native range. Although they have been introduced worldwide, they remain largely unstudied. The primary focus of this study was to relate Muscovy duck abundance to habitat characteristics of wetlands in Tampa, Florida. Muscovy abundance was measured using point count methods at 21 wetland sites that occur within an eight km radius of the University of South Florida’s main campus. Habitat features at these sites were assessed using field methods and Geographic Information Systems (GIS) …


Land Use, Stream Stability, And Benthic Invertebrates In A Dry Forest Watershed Of Western Costa Rica, Jacqueline Ann Demko Mar 2017

Land Use, Stream Stability, And Benthic Invertebrates In A Dry Forest Watershed Of Western Costa Rica, Jacqueline Ann Demko

USF Tampa Graduate Theses and Dissertations

There is a paucity of data on dry forests, the most threatened biome in the tropics. The Nandamojo is a tropical dry forest watershed in Western Costa Rica that has been impacted by varying degrees of human induced modifications. This research was conducted to examine the influence of land use and channel characteristics on invertebrate communities within a sub basin of the Nandamojo watershed. This study addressed three hypotheses: (1) sites with low tree cover and small riparian buffer zones will have high erosion, (2) macroinvertebrate abundance will be lower at sites with low channel stability values, and (3) benthic …


Bat Urea-Derived Minerals In Arid Environment. First Identification Of Allantoin, C4H6N4O3, In Kahf Kharrat Najem Cave, United Arab Emirates, Philippe Audra, Pavel Bosák, Fernando Gázquez, Didier Cailhol, Roman Skála, Lenka Lisá, Šárka Jonášová, Amos Frumkin, Martin Knez, Tadej Slabe, Nadja Zupan Hajna, Asma Al-Farraj Feb 2017

Bat Urea-Derived Minerals In Arid Environment. First Identification Of Allantoin, C4H6N4O3, In Kahf Kharrat Najem Cave, United Arab Emirates, Philippe Audra, Pavel Bosák, Fernando Gázquez, Didier Cailhol, Roman Skála, Lenka Lisá, Šárka Jonášová, Amos Frumkin, Martin Knez, Tadej Slabe, Nadja Zupan Hajna, Asma Al-Farraj

International Journal of Speleology

Kahf Kharrat Najem Cave is a small cave in United Arab Emirates (UAE) that hosts a bat colony which is the source of guano deposits and peculiar centimeter-long yellowish stalactites. The mineralogy and geochemistry of these deposits were analyzed using powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopic microanalysis (EDX), scanning electron microscope (SEM), and stable isotope composition (δ13C and δ15N). Urea CO(NH2)2 was found to be the main compound of these stalactites, while allantoin C4H6N4O3 was found to be an accessory urea byproduct. This paper …


Lilliput Effect Dynamics Across The Cretaceous-Paleogene Mass Extinction: Approaches, Prevalence, And Mechanisms, Matthew Brett Jarrett Dec 2016

Lilliput Effect Dynamics Across The Cretaceous-Paleogene Mass Extinction: Approaches, Prevalence, And Mechanisms, Matthew Brett Jarrett

USF Tampa Graduate Theses and Dissertations

An organism's body size entails both physiological and ecological costs. Furthermore, as a parameter in analyzing organisms, it represents a fundamental and essential morphometric character. Reductions in size following mass extinction is a commonly observed phenomenon in the fossil record. This study examines the evolutionary significance of this phenomenon termed the: 'Lilliput Effect' by proposing that it represents a rapid evolutionary response to altered selection pressures during a mass extinction. This primary hypothesis is evaluated against two additional hypotheses of size reduction: 1) stunted growth as a response to stressed ecosystems, and/or 2) mass extinctions are size selective.

These hypotheses …


An Ecosystem-Based Approach To Reef Fish Management In The Gulf Of Mexico, Michelle D. Masi Nov 2016

An Ecosystem-Based Approach To Reef Fish Management In The Gulf Of Mexico, Michelle D. Masi

USF Tampa Graduate Theses and Dissertations

Fisheries managers have the potential to significantly improve reef fish management in the Gulf of Mexico through the use of ecosystem-based approaches to fisheries management. Ecosystem-based approaches are needed to address the effects of fishing on trophodynamic interactions, to better account for ecosystem-scale processes in model projections, and to recognize the short and long-term biomass tradeoffs associated with making regulatory choices. My research was concentrated around three objectives: (1) characterizing the trophodynamic interactions between Gulf of Mexico fishes, in order to construct an invaluable tool (a Gulf of Mexico Atlantis model) to be used in ecological hypothesis testing and policy …


Optimizing Methods For Extraction Of Organic Compounds From Molluscan Shells, Kaydee Jo West Jun 2016

Optimizing Methods For Extraction Of Organic Compounds From Molluscan Shells, Kaydee Jo West

USF Tampa Graduate Theses and Dissertations

Mollusk shells contain proteins within and between the crystals of calcium carbonate. These organic molecules play an important role in biomineralization and shell function, and their stable isotope ratios of carbon and nitrogen are also thought to record important ecological information about the animal's diet and nutrient sources. These proteins can be preserved for millions of years, offering potential insight into pre-anthropogenic ecological conditions. However, shell organics in older shells are typically recovered in reduced abundances due to leaching and remaining organics are often converted from insoluble proteins to soluble, free amino acids, making them difficult to detect and recover. …


Pollutants And Foraminiferal Assemblages In Torrecillas Lagoon: An Environmental Micropaleontology Approach, Michael Martinez-Colon Jun 2016

Pollutants And Foraminiferal Assemblages In Torrecillas Lagoon: An Environmental Micropaleontology Approach, Michael Martinez-Colon

USF Tampa Graduate Theses and Dissertations

Torrecillas Lagoon in the North Coast of Puerto Rico has experienced extensive anthropogenic influence over the past 400 years. Elevated concentrations of Potential Toxic Elements (PTEs) have been reported in surficial sediments. The main goal of this dissertation was to implement in Puerto Rico the use of benthic foraminifers as a bioindicators of PTEs and to compare the impact of Cu(II) on field samples with results of experimental work using cultures.

Analyses included geochemical assessment for bulk and carbonate- soluble bioavailable concentrations of PTEs in surface, core and pore-water samples, as well as analyses of grain-size, Percent Total Organic Carbon …