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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.
61

Increasing Integrity in Sea-Level Rise Impact Assessment on Florida’s Coastal Everglades

Unknown Date (has links)
Over drainage due to water management practices, abundance of native and rare species, and low-lying topography makes the coastal Everglades especially vulnerable to Sea-Level Rise (SLR). Water depths have shown to have a significant relationship to vegetation community composition and organization while also playing a crucial role in vegetation health throughout the Everglades. Modeling potential habitat change and loss caused by increased water depths due to SLR requires better vertical Root Mean Square Error (RMSE) and resolution Digital Elevation Models (DEMs) and Water Table Elevation Models (WTEMs). In this study, an object-based machine learning approach was developed to correct LiDAR elevation data by integrating LiDAR point data, aerial imagery, Real Time Kinematic (RTK)-Global Positioning Systems (GPS) and total station survey data. Four machine learning modeling techniques were compared with the commonly used bias-corrected technique, including Random Forest (RF), Support Vector Machine (SVM), k-Nearest Neighbor (k-NN), and Artificial Neural Network (ANN). The k-NN and RF models produced the best predictions for the Nine Mile and Flamingo study areas (RMSE = 0.08 m and 0.10 m, respectively). This study also examined four interpolation-based methods along with the RF, SVM and k-NN machine learning techniques for generating WTEMs. The RF models achieved the best results for the dry season (RMSE = 0.06 m) and the wet season (RMSE = 0.07 m) WTEMs. Previous research in Water Depth Model (WDM) generation in the Everglades focused on a conventional-based approach where a DEM is subtracted from a WTEM. This study extends the conventional-based WDM approach to a rigorous-based WDM technique where Monte Carlo simulation is used to propagate probability distributions through the proposed SLR depth model using uncertainties in the RF-based LiDAR DEM and WTEMs, vertical datums and transformations, regional SLR and soil accretion rates. It is concluded that a more rigorous-based WDM technique increases the integrity of derived products used to support and guide coastal restoration managers and planners concerned with habitat change under the challenge of SLR. Future research will be dedicated to the extension of this technique to model both increased water depths and saltwater intrusion due to SLR (saltwater inundation). / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection
62

The Associations of Little Blue Heron Prey and Vegetation Communities in Two Subtropical Coastal Ecosystems

Unknown Date (has links)
Shallow water availability coupled with anthropogenic degradation of seagrass beds limits wading bird food resources in dynamic coastal ecosystems. Identifying prey species critical to wading bird reproductive success and the environmental drivers of key prey species abundance is important for understanding how environmental stressors influence prey and change the quality of foraging patches. Little Blue Herons (Egretta caerulea) are reportedly generalists eating insects, crustaceans, and fish; however, the proportions of prey items in the diet may shift spatially and temporally from freshwater to marine systems during breeding and non-breeding periods. I investigated prey selection by Little Blue Herons in Florida at the Great White Heron National Wildlife Refuge and the western Florida Bay, during 2016 and 2017 breeding seasons by investigating prey availability at low-tide locations along mudflats compared to stomach regurgitate samples collected from Little Blue Heron chicks 1 to 4 weeks old. Little Blue Herons selected Gulf toadfish (Opsanus beta) and prawns (Farfantepenaeus spp.) from the estuarine environment, but also consumed terrestrial prey (e.g. tree crabs) suggesting Little Blue Heron foraging habitat is not restricted to tidal flats. Additionally, these results support the characterization of Little Blue Herons as a generalist. After identifying important prey species, I modeled the associations of selected prey species with submerged aquatic vegetation density and abiotic variables to better understand habitat preferences and important habitat characteristics that drive prey density. Models support total seagrass density and algal density as having the greatest effect on prey selected by Little Blue Herons. Prawn density has a strong positive association with seagrass density. Gulf toadfish (Opsanus beta) and prawns (Farfantepenaeus spp.) had strong positive association with algae while pipefish (Syngnathidae) had a strong negative association with algae suggesting algae density in seagrass meadows should be considered when assessing the quality of seagrass meadows for Little Blue Heron prey and habitat suitability. My results varied from previous studies where prawns and gulf toadfish were associated with specific seagrass species. Therefore, some Little Blue Heron prey species in south Florida may not be affected by changes in submerged aquatic vegetation community composition if submerged aquatic vegetation densities remain constant. Studies are needed that clarify the complex interactions between prey and specific habitat metrics to validate the strength of landscape scale drivers of wading bird prey densities in dynamic coastal ecosystems and to determine how these communities will respond to anthropogenic environmental change. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection
63

The role of collaboration in everglades restoration

Frank, Kathryn Irene 21 August 2009 (has links)
This dissertation examined the impacts of multiple collaborative planning and implementation processes on ecosystem management of the Everglades wetlands of South Florida. In particular, the research focused on collaboration's role in (1) reducing phosphorus pollution in runoff from the Everglades Agricultural Area in the historic northern Everglades and (2) improving the water flow regime in Shark Slough of the southern Everglades. Restoration of the greater Everglades watershed is the largest such initiative in the world, and it may also be the most collaborative, with scores of these processes used at various scales since the mid-1960s. Ecosystem management is the most advanced approach to environmental governance, and its three tenets of integrative, adaptive, and ecologically protective governance provide a framework for evaluating environmental planning processes. Proponents of collaborative processes believe they are exceptionally suited to promoting the tenets of ecosystem management. Critics of collaboration, however, are concerned with the potential for cooptation of environmental interests, among other issues. Using qualitative case study methodology, the research found that collaborative processes improved ecosystem management, but not to the degree expected by collaboration proponents. Collaborative processes were integrative of values, information, activities, and political support across the ecosystem, yet integration had biases and limits as a result of groups' strategic behaviors and processes' emphasis on reaching agreement rather than fully exploring the issues. Cooptation of environmental interests was not a significant problem. Collaborative processes promoted adaptation and social learning in specific cases, but at a macro level helped to maintain the status quo of the dominant water management agencies and technocratic paradigms. Process outcomes were protective of ecological health in that they made steady, incremental progress towards ecological restoration. Progress had significant setbacks however, because collaboratively developed policies were subject to capture by economic interests. Despite the collaborative improvements in ecosystem management, ecological health remains a distant and uncertain prospect for the Everglades.
64

Measuring tradition and variation a St. Johns II pottery assemblage from the shields site (8DU12) /

Rolland, Vicki L. Marrinan, Rochelle A. January 2004 (has links)
Thesis (M.S.)--Florida State University, 2004. / Advisor: Dr. Rochelle A. Marrinan, Florida State University, College of Arts and Sciences, Dept. of Anthropology. Title and description from dissertation home page (viewed 6/16/04). Includes bibliographical references.
65

From mosquito clouds to war clouds the rise of Naval Air Station Banana River /

Euziere, Melissa Williford. Jones, James Pickett. January 2003 (has links)
Thesis (M.A.)--Florida State University, 2003. / Advisor: Dr. James P. Jones, Florida State University, College of Arts and Sciences, Dept. of History. Title and description from dissertation home page (viewed Jan, 31, 2005). Includes bibliographical references.
66

Greater Jacksonville's response to the Florida land boom of the 1920s

Miller, Philip Warren, January 1989 (has links) (PDF)
Thesis (M.A.)--University of Florida, 1989. / Completed through the joint cooperative program of the History Departments of the University of Florida and the University of North Florida. Includes bibliographical references (leaves 169-178).
67

Energy basis of a coastal region: Franklin County and Apalachicola Bay, Florida

Boynton, W. R. January 1975 (has links)
Thesis--University of Florida. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 376-388).
68

A bioarchaeological assessment of health from Florida's archaic application of the Western Hemisphere Health Index to the remains from Windover (8BR246) /

Wentz, Rachel Kathleen. Doran, Glen H. January 2006 (has links)
Thesis (Ph. D.)--Florida State University, 2006. / Advisor: Glen H. Doran, Florida State University, College of Arts and Sciences, Dept. of Anthropology. Title and description from dissertation home page (viewed June 13, 2006). Document formatted into pages; contains xii, 126 pages. Includes bibliographical references.
69

Morphodynamics of a constructed marsh Project Greenshores, Pensacola, Florida /

Hobbs, Chasidy Marie. January 2007 (has links)
Thesis (M.S.)--University of West Florida, 2007. / Title from title page of source document. Document formatted into pages; contains 65 pages. Includes bibliographical references.
70

Identification and characterization of molecular players potentially responsible for the mechanical properties of tension wood / Identification et caractérisation des acteurs moléculaires potentiellement responsables pour des propriétés mécaniques du bois de tension

Šećerović, Amra 29 November 2016 (has links)
Le but de cette thèse était d’identifier les mécanismes moléculaires responsables des propriétés particulières de la couche G et les propriétés mécaniques remarquables du bois de tension (BT). Trois acteurs moléculaires potentiels (des protéines à arabinogalactane avec domaine fasciclin-like (FLA), une protéine chitinase-like (CTL) et une β-galactosidase (BGAL)) ont été choisis et étudiés dans: analyse phylogénétique, analyses d'expression et caractérisation de peupliers transgéniques affectés dans l’expression de chacun de ces acteurs. La caractérisation fine de ce matériel a révélé que CTL2 et les FLA jouent un rôle dans la régulation de la cristallinité de la cellulose dans le BT. CTL2 apparaît également important dans l'organisation de la paroi cellulaire et des propriétés mécaniques des tiges. BGAL a été avant proposé pour une fonction dans modification de pectine RG-I potentiellement important pour des propriétés mécaniques de BT. Le bois de tension exhibe une activité BGAL plus élevée que dans le bois opposé. L’inhibition par RNAi de l’expression de BGAL7, spécifiquement exprimée dans le BT, n’est pas responsable à lui seul de la forte activité BGAL présente dans le BT. En contrepoint à l’étude menée sur le peuplier, nous avons également évalué la présence d’acteurs moléculaires potentiellement responsables des propriétés mécaniques du BT chez le simarouba qui développe dans leur BT des fibres ayant leurs sous-couches de la paroi intermédiaire entre la G et la S2. Des protéines à arabinogalactanes ainsi que des pectines du type RG-I sont présentes dans les fibres de BT de peuplier et de simarouba et pourraient avoir une fonction dans un mécanisme commun de génération des contraintes dans le BT. Finalement, un modèle est proposé sur le rôle présumé des différents acteurs moléculaires étudié dans la régulation des propriétés de la couche G et la génération des fortes contraintes du bois de tension. / The aim of this thesis was to approach the underlying molecular mechanisms responsible for the particular properties of the G-layer and the outstanding mechanical properties of tension wood (TW). Accordingly, three potential molecular players (fasciclin-like arabinogalactan protein (FLA), chitinase-like protein (CTL) and β-galactosidase (BGAL)) were chosen and studied through a phylogenetic analysis, expression analyses and most importantly characterization of RNAi transgenic poplars. This multilevel characterization revealed that CTL2 and FLAs have function in the regulation of cellulose crystallinity in TW. CTL2 was also shown to be important both for the cell wall organization and stem mechanical properties. BGAL was studied in a light of the previously reported modifications of RG-I pectin, potentially important for the mechanical properties of TW. Study of BGAL revealed that the enzyme has higher activity in TW than in opposite wood. BGAL7, whose gene was expressed specifically in TW, does not seem to be responsible for the higher BGAL activity in TW. In comparison to poplar, we analyzed the occurrence of molecular players potentially responsible for TW mechanical properties in simarouba, a tropical species, which develops different TW fiber. Arabinogalactan proteins and RG-I pectin potentially targeted by BGAL were localized in TW fibers both in poplar and simarouba and therefore may be involved in a common mechanism of tensile stress generation in different TW types. A model was finally proposed to elucidate a potential function of the studied molecular players in the regulation of G-layer properties and tensile stress generation.

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