Evaluation of Anthropogenic Contaminants in Subtropical Aquatic Ecosystems After Catastrophic Events
ORCID ID
0000-0003-4083-2090
Date of Award
8-2024
Degree Type
Dissertation
Degree Name
Ph.D.
Degree Program
Chemistry
Department
Chemistry
Major Professor
Zito, Phoebe
Second Advisor
Archer, Stephanie
Third Advisor
Wiley, John
Fourth Advisor
Podgorski, David
Abstract
Coastal marine ecosystems are particularly affected by climate change, experiencing rising sea levels and increased erosion, which impact their biodiversity and productivity. Hurricanes, intensified by climate change, bring substantial alterations to marine environments, introducing a variety of anthropogenic contaminants that exacerbate their effects on nearshore ecosystems. Despite these impacts, there is still limited understanding of the specific effects that hurricanes have on coastal marine ecosystems, highlighting the need for further research and monitoring to better comprehend and mitigate these environmental changes. Metal concentrations in surface water, sediment, and seagrass from Abaco after Hurricane Dorian were studied. The results indicate higher contamination in marinas compared to seagrass beds, suggesting the need for remediation strategies. The data demonstrates potential impact of natural disturbances on HM variability in seagrasses and sediments, while bioconcentration factors suggest seagrasses around Abaco primarily uptakes HMs from surface water. Significant correlations between certain metal concentrations in seagrass/sediment and seagrass/surface water suggest similar metal sources. Site-specific risk assessments are necessary to protect seagrasses and associated organisms. Metal concentrations in surface water, sediment, and oyster tissue in Bayou Petit Caillou were analyzed after Hurricane Ida. The results showed that several elements exceeded toxicity thresholds established by NOAA and international regulations. The linear regression analysis revealed complex relationships between environmental factors and heavy metal concentrations, with significant effects observed for pH, temperature, salinity, and dissolved organic matter. The concentration of vanadium in sediments showed significant correlation with resulting hurricane debris present in the bayou. The presence of benzo(a)pyrene in Caribbean spiny lobster and queen conch collected from Abaco Island, The Bahamas, was investigated. An optimized QuEChERS extraction method was employed for the extraction of benzo(a)pyrene, followed by analysis using gas chromatography-mass spectrometry. The results demonstrated the absence of benzo(a)pyrene in the tissue samples. Overall, the results of this dissertation provide insights into the environmental health in coastal marine ecosystems in Abaco Island and Louisiana and the importance of continued monitoring and management strategies to safeguard the marine environments and the organisms they support.
Recommended Citation
Salas Ortiz, Yanila, "Evaluation of Anthropogenic Contaminants in Subtropical Aquatic Ecosystems After Catastrophic Events" (2024). University of New Orleans Theses and Dissertations. 3194.
https://scholarworks.uno.edu/td/3194
Rights
The University of New Orleans and its agents retain the non-exclusive license to archive and make accessible this dissertation or thesis in whole or in part in all forms of media, now or hereafter known. The author retains all other ownership rights to the copyright of the thesis or dissertation.