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PREDICTING RISKS OF INVASION OF CAULERPA SPECIES IN FLORIDA
Title
PREDICTING RISKS OF INVASION OF CAULERPA SPECIES IN FLORIDA.
Creator
Glardon, Christian, Walters, Linda, University of Central Florida
Abstract / Description
Invasions of exotic species are one of the primary causes of biodiversity loss on our planet (National Research Council 1995). In the marine environment, all habitat types including estuaries, coral reefs, mud flats, and rocky intertidal shorelines have been impacted (e.g. Bertness et al. 2001). Recently, the topic of invasive species has caught the public's attention. In particular, there is worldwide concern about the aquarium strain of the green alga Caulerpa taxifolia (Vahl) C. Agardh...
Show moreInvasions of exotic species are one of the primary causes of biodiversity loss on our planet (National Research Council 1995). In the marine environment, all habitat types including estuaries, coral reefs, mud flats, and rocky intertidal shorelines have been impacted (e.g. Bertness et al. 2001). Recently, the topic of invasive species has caught the public's attention. In particular, there is worldwide concern about the aquarium strain of the green alga Caulerpa taxifolia (Vahl) C. Agardh that was introduced to the Mediterranean Sea in 1984 from the Monaco Oceanographic Museum. Since that time, it has flourished in thousands of hectares of near-shore waters. More recently, C. taxifolia has invaded southern Californian and Australian waters. Since the waters of Florida are similar to the waters of the Mediterranean Sea and other invasive sites my study will focus on determining potential invasion locations in Florida. I will look at the present distribution of C. taxifolia - native strain in Florida as well as the distribution of the whole genus around the state. During this study, I address three questions: 1) What is the current distribution of Caulerpa spp. in Florida? 2) Can I predict the location of potential Caulerpa spp. invasions using a set of environmental parameters and correlate them to the occurrence of the algae with the support of Geographic Information System (GIS) maps? 3) Using the results of part two, is there an ecological preferred environment for one or all Caulerpa spp. in Florida? To answer these questions, I surveyed 24 areas in each of 6 zones chosen in a stratified manner along the Floridian coastline to evaluate the association of potential indicators Caulerpa. Latitude, presence or absence of seagrass beds, human population density, and proximity to marinas were chosen as the 4 parameters expected to correlate to Caulerpa occurrences. A logistic regression model assessing the association of Caulerpa occurrence with measured variables has been developed to predict current and future probabilities of Caulerpa spp. presence throughout the state. Fourteen different species of Caulerpa spp. were found in 26 of the 132 sites visited. There was a positive correlation between Caulerpa spp. and seagrass beds presence and proximity to marinas. There was a negative correlation with latitude and human population density. C. taxifolia – aquarium strain wasn't found. Percent correct for our model was of 61.5% for presence and 98.1% for absence. This prediction model will allow us to focus on particular areas for future surveys.
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Date Issued
2006
Identifier
CFE0001041, ucf:46796
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0001041
RECESSION TO DEPRESSION: A CRITICAL DISAMBIGUATION OF THE 2007/2008 FINANCIAL CRISIS AND A MODEL FOR NEW AGE SECURITIES REGULATION.
Title
RECESSION TO DEPRESSION: A CRITICAL DISAMBIGUATION OF THE 2007/2008 FINANCIAL CRISIS AND A MODEL FOR NEW AGE SECURITIES REGULATION.
Creator
Walters, Christian, Milon, Abby, University of Central Florida
Abstract / Description
During the late 2000s the United States economy was faced with the most traumatic event in United States financial history since the Great Depression. Large multibillion dollar corporations collapsed, families lost their life savings, and the United States economy stood on a precipice for total destruction. In the wake of the Financial Crisis, investment firms such as Merrill Lynch collapsed and their portfolios were sold to competitors for far lower than their estimated value (Sorkin). In...
Show moreDuring the late 2000s the United States economy was faced with the most traumatic event in United States financial history since the Great Depression. Large multibillion dollar corporations collapsed, families lost their life savings, and the United States economy stood on a precipice for total destruction. In the wake of the Financial Crisis, investment firms such as Merrill Lynch collapsed and their portfolios were sold to competitors for far lower than their estimated value (Sorkin). In 2008, the Financial Crisis impacted the working man the most. With foreclosures on the rise, an estimated 81.2% increase from the year before, average citizens lost their homes, savings and certainty in the United States Government to protect their best interests (Armour). One of the hardest hit states, Nevada, saw a total foreclosure rate of about 7.3% which was an increase from the previous year of a staggering 125.7% (Armour). All these foreclosures rippled throughout the U.S housing market and made it nigh impossible for the banks securing the loans to collect upon the principle amount loaned, yet alone the interest. The shock from the United States financial sector echoed throughout the world. Correlating with the Financial Crisis, United States and global suicide rates were on the rise. According to a 2009 Article published by the British Medical Journal, United States suicide rates in men age 45-64 increased by over 6.4% of the expected trend ("Male Suicide Rate Rose during 2008 Global Economic Crisis, Says Time-Trend Study"). The Financial Crisis made it so that average individuals felt increased economic strain and an ever looming sense of disparagement. This is an examination and evaluation of the perhaps one of the greatest schemes in the history of global financial markets; this is a critical analysis of how greed, power and a lack of moral decency reshaped the world. This is an examination of how, in an age of deregulation, the powerful seemingly take precedence over the masses. This is the Story of the 2007/2008 Recession, of what has been done, of what we need to do, and of moving forward to assign blame and punishment to those responsible for the pain and suffering incurred by so many.
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Date Issued
2015
Identifier
CFH0004817, ucf:45474
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFH0004817
Hydrodynamic Limitations and the Effects of Living Shoreline Stabilization on Mangrove Recruitment along Florida Coastlines
Title
Hydrodynamic Limitations and the Effects of Living Shoreline Stabilization on Mangrove Recruitment along Florida Coastlines.
Creator
Pilato, Christian, Walters, Linda, Kibler, Kelly, Quintana-Ascencio, Pedro, University of Central Florida
Abstract / Description
The recruitment success of mangroves is influenced by a variety of factors, including propagule availability, desiccation, herbivory, and hydraulic habitat limitations. Hydrodynamic forces (waves and currents) act as obstacles to mangrove recruitment, restricting the successful colonization of mangrove species. We evaluated the biological and physical limitations to mangrove recruitment through monthly shoreline surveys and lateral pull-tests. Surveys followed mangroves from propagule release...
Show moreThe recruitment success of mangroves is influenced by a variety of factors, including propagule availability, desiccation, herbivory, and hydraulic habitat limitations. Hydrodynamic forces (waves and currents) act as obstacles to mangrove recruitment, restricting the successful colonization of mangrove species. We evaluated the biological and physical limitations to mangrove recruitment through monthly shoreline surveys and lateral pull-tests. Surveys followed mangroves from propagule release through recruitment along the shorelines of De Soto National Memorial (Bradenton, FL), capturing differences in propagule availability and recruitment along natural areas and across differing forms of shoreline stabilization ((")living shorelines(") and revetments). Propagule densities were highest along (")living shorelines("), followed by natural areas and revetments. Seedling densities were similar across treatments, mirroring densities found in disturbed mangrove systems in the Philippines ((<)1 seedling per m2). Pull-tests, simulating wave forces, quantified the physical thresholds for uprooting Rhizophora mangle and Avicennia germinans seedlings in both the greenhouse and field. Uprooting susceptibility significantly decreased with increased seedling biomass and age. A. germinans displayed a lower force to removal than R. mangle, but showed a greater increase in uprooting force with increases in size. Surrounding vegetation and canopy cover were not found to significantly affect the uprooting force of either species. Pull-test results were used in conjunction with drag coefficients from the literature to calculate flow velocities where mangroves would become susceptible to dislodgement from hydrodynamic forces. Seedlings tested would become susceptible at velocities of 7.33 (&)#177; 2.07 m/s for A. germinans and 5.40 (&)#177; 1.59 m/s for R. mangle. The rapid increase in force to removal shows the importance of disturbances, such as erosion, driving seedling dislodgment at the local scale. This research strengthens our understanding of the physical conditions conducive to successful recruitment under hydrodynamic stressors and provides insight into how a common restoration method can influence mangrove recruitment.
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Date Issued
2019
Identifier
CFE0007899, ucf:52748
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007899