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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Fine-scale geographic variation of stable isotope and fatty acid signatures of three fish species in the Indian River Lagoon, FL

Odom, Jennifer Fletcher 01 January 2012 (has links)
The Indian River Lagoon, Florida, is a unique closed “bar built” estuary system that has little interchange with the Atlantic Ocean and which is home to many resident species. Three fish species were investigated to see if their isotopic and fatty acid signatures differed based on geographic location. The goal was to assess the degree of resolution of spatial variation that is possible when using stable isotope and fatty acid signature analysis to interpret feeding habits and potential linkages between feeding habits and health status. Spotted seatrout (n=40), pinfish (n=60) and white mullet (n=60) were collected over a 4 week period at sites 30 km apart in two distinct biogeographic regions of the IRL. Fish were analyzed for stable isotope (δ13C and δ15N) and fatty acid composition. All three species were significantly different from each other in both isotopic and fatty acid signatures. In the North Indian River segment, spotted seatrout, white mullet and pinfish had mean values (± SE) for δ13C of -18.00 ± 0.08, -14.59 ± 0.07 and -16.88 ± 0.04 respectively and for δ15N, mean values were 14.43 ± 0.05, 8.30 ± 0.04 and 10.43 ± 0.03 respectively. For the North-Central Indian River segment, spotted seatrout, white mullet and pinfish had mean values for δ13C of -18.98 ± 0.02, -16.25 ±0.06 and -16.94 ± 0.04 respectively and for δ15N, mean values were 14.21 ± 0.02, 8.07 ± 0.03 and 10.64 ±0.03 respectively. When species and location interactions were examined using ANCOVA, a post-hoc Tukey’s HSD test showed that δ13C was significantly affected by sampling segment only for spotted seatrout and that there was no significant effect of location on δ15N values. Spotted seatrout was the only species that differed between segments for δ13C. Classification and Regression Tree (CART) analysis was then performed on the “extended dietary fatty acids” for each individual species and collection location. In this analysis, all three species were correctly identified to segment (white mullet - MR 2/53 p~ 0.03; spotted seatrout (MR 0/40), and pinfish (MR 0/56) indicating that individual species were exhibiting significant differences in their fatty acid signature over distances of 30 km. The ability to discern fine-scale differences in potential prey allows for the possibility of better resolution of dolphin feeding habits and hence a better understanding of both habitat utilization and health impacts. Due to limited exchange of clean salt water, contaminants can theoretically become a problem and there are indications that the health of the resident population of bottlenose dolphins (Tursiops truncatus) has been declining over recent years.
12

Investigating the Quantity and Types of Microplastics in the Organic Tissue of Oysters and Crabs in the Indian River Lagoon

Waite, Heidi 01 January 2017 (has links)
Microplastics are widespread and abundant. Few studies have examined the diversity and abundance of microplastics in wild organisms. This study determined the microplastic quantity and types in the organic tissues of the eastern oyster Crassostrea virginica and Atlantic mud crab Panopeus herbstii from the Indian River Lagoon (IRL). This study also investigated whether location affected the microplastic abundance and variety. Organisms were collected from three sites across Mosquito Lagoon in the northern IRL. Oysters were frozen after collection. Crabs were placed in containers for 5 days before freezing. The soft organic tissue was chemically digested using hydrogen peroxide, filtered, and examined for microplastics. Water samples collected from each study site had an average of 23.1 microplastic pieces per liter and fibers were the most common type. There was a significant interaction for microplastic type and site for both oysters and crabs (p
13

Isolation of Characterization of an Endemic Population of Vibrio Cholerae in the Florida Indian River Lagoon

Ganan, Carolina 01 January 2019 (has links)
Vibrio choleraeis the etiological agent of the severe diarrheal disease-cholera and natural inhabitant of estuarine and coastal waters. The proximity of the Florida Indian River Lagoon (IRL) to areas affected by recent cholera outbreaks makes this estuary ideal to investigate the environmental dynamics and their potential role in V. cholerae's pathogen emergence. We identified two locations in the IRL, Feller's House UCF Field Station and Shepard Park, as our collection sites. We collected samples from three different fractions - water, plankton, and sediment - and recorded data for several water parameters such as pH, temperature, and, turbidity. In the laboratory, we enriched samples in alkaline peptone water and isolated V. choleraeusing widely used selective media Thiosulfate-Citrate Bile Salts-sucrose agar (TCBS) and CHROMagar Vibrio. From our study, we isolated 100 potential V. cholerae isolates, which were confirmed using biochemical tests such as oxidase and Kligler's Iron Agar. V. cholerae has allelic variations in the core genes such as ompU, which provide pre-adaptation to virulence. We investigated the allelic variations within ompU to characterize V. cholerae isolates. We elucidated the sequenced allele of ompU and built a neighboring-joining phylogeny tree to view the differentiation among vibrios. Our findings provide insight into the endemic population of V. cholerae in the Eastern Coast of Florida. Further studies include a screen for additional virulence genes and investigate the role of environmental dynamics on the distribution of V. cholerae and emergence as a human pathogen.
14

Field-validated inter-comparison of Sentinel-2 MSI and Sentinel-3 OLCI images to assess waterquality in the Indian River Lagoon, Florida

Woodman, McKenzie Leonard 27 July 2023 (has links)
No description available.
15

Quantifying The Success Of Eastern Oyster Pilot Reefs In Brevard County, Florida

Anderson, Lacie 01 January 2016 (has links)
Crassostrea virginica, the eastern oyster, is a native keystone species that inhabits many coastal and estuarine ecosystems along the Atlantic seaboard. Introduction of the eastern oyster into estuarine areas with limited current populations is gaining popularity as a pro-active approach to improve estuarine water quality. In November 2014 and April 2015, a total of five pilot oyster reef treatments were deployed in Brevard County: bagged adult oysters (grown by community members under their docks through oyster gardening) collected in fall 2014 and spring 2015, bagged clean shell, oyster restoration mats, and empty plots (control). Locations of deployment included a Merritt Island impoundment (Marsh Harbor), Nicol Park (Port St. John), and Scout Island (Melbourne Beach). Prior to deployment, we collected morphometric data (shell length, weight) on all gardened oysters. Abiotic factors including salinity, air and water temperature, and wind speed were collected monthly. During quarterly sampling at each site, morphometric data were collected for all live oysters, surviving and newly recruited. Results show survival of gardened oysters and natural recruitment differed by and depended greatly on the within-site location of each reef. In areas with no recruitment and limited gardened oyster survival, regular deployment of gardened oysters is needed for long term success. In areas with natural recruitment, bagged, clean shell or oyster restoration mats are most successful. Future restoration sites should be tested prior to any large-scale oyster deployments.
16

Interactions between the Indian River Lagoon blue crab fishery and the bottlenose dolphin Tursiops truncatus

Noke, Wendy D. 01 January 1999 (has links)
No description available.
17

A generalized stochastic birth/death population model based on Indian RiverLagoon dolphins

Unknown Date (has links)
For over a decade, researchers at Harbor Branch Oceanographic Institute (HBOI) have conducted surveys of the bottlenose dolphin (Tursiops truncatus) population of Indian River Lagoon (IRL) in Florida. I have constructed a 4-stage population model using the statistical program R. The model is used to conduct a viability analysis by analyzing the relationship between birth, calf and adult survival rates. The power analysis compares survey frequency to expected confidence intervals in estimating abundance. The sensitivity analysis shows that the population is most sensitive to changes in adult survival, followed by birth rate and calf survival. The model shows a strong chance of viability over a 50 year time span. The population is vulnerable to long periods of decline if birth, calf or adult survival rates fall below certain thresholds. Overall, the model simulates the future impacts of demographic change, providing a tool for conservation efforts. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
18

Generating space-time hypotheses in complex social-ecological systems

Unknown Date (has links)
As ecosystems degrade globally, ecosystem services that support life are increasingly threatened. Indications of degradation are occurring in the Northern Indian River Lagoon (IRL) estuary in east central Florida. Factors associated with ecosystem degradation are complex, including climate and land use change. Ecosystem research needs identified by the Millennium Ecosystem Assessment (MA) include the need to: consider the social with the physical; account for dynamism and change; account for complexity; address issues of scale; and focus on ecosystem structure and process. Ecosystems are complex, self-organizing, multi-equilibrial, non-linear, middle-number systems that exist in multiple stable states. Results found are relative to the observation and the frame of analysis, requiring multi-scaled analytical techniques. This study addresses the identified ecosystem research needs and the complexity of the associated factors given these additional constraints. Relativity is addressed through univariate analysis of dissolved oxygen as a measure of the general health of the Northern IRL. Multiple spatial levels are employed to associate social process scales with physical process scales as basin, sub-basins, and watersheds. Scan statistics return extreme value clusters in space-time. Wavelet transforms decompose time-scales of cyclical data using varying window sizes to locate change in process scales in space over time. Wavelet transform comparative methods cluster temporal process scales across space. Combined these methods describe the space-time structure of process scales in a complex ecosystem relative to the variable examined, where the highly localized results allow for connection to unexamined variables. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
19

Population structure and dispersal of bottlenose dolphins (Tursiops truncatus) of the Indian River Lagoon Estuary, Florida, and adjacent Atlantic waters

Unknown Date (has links)
Worldwide research of bottlenose dolphins (Tursiops truncatus) has led to varied definitions and terminology regarding ways to group dolphins for study and management. An understanding of the demographic history and population structure of bottlenose dolphins residing within the Indian River Lagoon Estuary System (IRLES), Florida, is needed to help define the IRLES dolphin population: ecotype, population, or community. Using mitochondrial DNA sequencing and microsatellite genotyping, this study detected: (1) genetic differentiation between estuarine and coastal individuals (FstmtDNA=0.414, Fstmsat=0.057; p<0.05; K=2), (2) genetic differentiation between the Indian River Lagoon (IRL) and Mosquito Lagoon (ML) (FstmtDNA=0.0201, Fstmsat=0.0234; p<0.09), and (3) minute undefined sub-structure within the IRLES (FstmtDNA=-0.00 -0.0379, Fstmsat=0.00 - vii 0.0445; p>0.1). Additionally, within ML this study detected non-mixing cohabitation of two potential ecotypes, estuarine and coastal. These findings raise many questions regarding how dolphins are presently categorized and managed which are critical to population assessments including abundance, vital rates, and health. / by Sarah E. Rodgers. / Thesis (M.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
20

The effects of on-site sewage treatment and disposal systems on the relief canals of Indian River County, the St. Sebastian River, and the central Indian River lagoon

Unknown Date (has links)
Effluent from on-site sewage treatment and disposal systems (OSTDS) is generally known to impact groundwaters and surface waters with nitrogen (N) and phosphorus (P) and other contaminants. Little research has quantified this problem along the Indian River Lagoon (IRL), especially in Indian River County (IRC) where there are 26,660 active systems. This study assessed the effects of OSTDS on contamination of surface and groundwaters along three urbanized canals and the St. Sebastian River in IRC, all of which flow into the Central IRL. Multiple lines of evidence were used to define the source of the nutrient loadings including the novel approach of using the artificial sweetener, sucralose, as an indicator of human sewage impact. Results indicate that areas with high densities of OSTDS are contributing N to surface waters and elevating N:P ratios through submarine groundwater discharge and promoting eutrophication in the Central IRL. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

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