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2010

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The Effects Of A Freshwater Diversion Of Nekton Species Biomass Distributions, Food Web Pathways, And Community Structure In A Louisiana Estuary, Kim De Mutsert Jan 2010

The Effects Of A Freshwater Diversion Of Nekton Species Biomass Distributions, Food Web Pathways, And Community Structure In A Louisiana Estuary, Kim De Mutsert

LSU Doctoral Dissertations

A current method to restore Louisiana’s estuaries includes reintroducing freshwater and sediments to wetlands that are hydrologically isolated from the Mississippi River due to the construction of levees. In this dissertation, I examined effects of the second largest freshwater diversion in Louisiana, the Caernarvon Freshwater Diversion (CFD), on estuarine nekton in Breton Sound. Before focusing on Breton Sound, I examined the status of nekton communities in the northern Gulf of Mexico (GOM), and Louisiana wetlands in particular, using the mean trophic level index (MTLI). I demonstrated that commercial targeting caused the previously reported low and declining MTLI from the GOM. …

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Corrosion Behavior Of Copper Thin Films In Organic Hf-Containing Cleaning Solution For Semiconductor Applications, Nabil George Mistkawi, Makarem A. Hussein, Malgorzata Ziomek-Moroz, Shankar B. Rananavare Jan 2010

Corrosion Behavior Of Copper Thin Films In Organic Hf-Containing Cleaning Solution For Semiconductor Applications, Nabil George Mistkawi, Makarem A. Hussein, Malgorzata Ziomek-Moroz, Shankar B. Rananavare

Chemistry Faculty Publications and Presentations

The corrosion behavior of electrochemically deposited copper thin films in deaerated and non-deaerated commercial cleaning solutions containing HF was investigated. Potentiodynamic polarization experiments were carried out to determine active, active–passive, passive, and transpassive regions. Corrosion rates were calculated from Tafel slopes. The addition of hydrogen peroxide to the solution and its influence on corrosion was also investigated by employing inductively coupled plasma-mass spectroscopy (ICP-MS) and X-ray photoelectron spectroscopy (XPS). The ICP-MS and potentiodynamic methods yielded comparable Cu dissolution rates. Surface analysis using atomic force microscopy and scanning electron microscopy, performed before and after the cleaning solution treatment, did not reveal …

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Friction And Wear At Elevated Velocities, Adam Lodygowski Jan 2010

Friction And Wear At Elevated Velocities, Adam Lodygowski

LSU Doctoral Dissertations

Severe contact stress problems generate high temperature and create thermomechanical gouging and wear due to high velocity sliding between contacting materials. The major consideration is to develop an experimental and theoretical model for the material constitutive behavior in order to better characterize and predict the internal failure surroundings the gouging and wear events and understand the physical behavior of high speed contact environment. An enhancement of an existing tribometer device developed by Philippon et al. [2004] is made up of a dynamometer ring and a load sensor that allows to apply an apparent normal force on specimens and measure frictional …

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Hamilton-Jacobi Theory For Optimal Control Problems On Stratified Domains, Richard Charles Barnard Jan 2010

Hamilton-Jacobi Theory For Optimal Control Problems On Stratified Domains, Richard Charles Barnard

LSU Doctoral Dissertations

This thesis studies optimal control problems on stratified domains. We first establish a known proximal Hamilton-Jacobi characterization of the value function for problems with Lipschitz dynamics. This background gives the motivation for our results for systems over stratified domains, which is a system with non-Lipschitz dynamics that were introduced by Bressan and Hong. We provide an example that shows their attempt to derive a Hamilton-Jacobi characterization of the value function is incorrect, and discuss the nature of their error. A new construction of a multifunction is introduced that possesses properties similar to those of a Lipschitz multifunction, and is used …

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The Impact Of Overfitting And Overgeneralization On The Classification Accuracy In Data Mining, Huy Nguyen Anh Pham Jan 2010

The Impact Of Overfitting And Overgeneralization On The Classification Accuracy In Data Mining, Huy Nguyen Anh Pham

LSU Doctoral Dissertations

Current classification approaches usually do not try to achieve a balance between fitting and generalization when they infer models from training data. Such approaches ignore the possibility of different penalty costs for the false-positive, false-negative, and unclassifiable types. Thus, their performances may not be optimal or may even be coincidental. This dissertation analyzes the above issues in depth. It also proposes two new approaches called the Homogeneity-Based Algorithm (HBA) and the Convexity-Based Algorithm (CBA) to address these issues. These new approaches aim at optimally balancing the data fitting and generalization behaviors of models when some traditional classification approaches are used. …

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Edaphic And Vegetative Controls On Mercury Cycling In Oligohaline Wetlands, Jonathan M. Willis Jan 2010

Edaphic And Vegetative Controls On Mercury Cycling In Oligohaline Wetlands, Jonathan M. Willis

LSU Doctoral Dissertations

With the expansion of the human population and associated industries there is a concomitant increase in both resource utilization and the production of waste and deleterious by-products. Mercury is a naturally-occurring toxic metal with a complicated and unique biogeochemical cycle, and is often a contaminant of ecotoxicological concern in unindustrialized aquatic habitats. The research described herein was designed to elucidate multiple aspects regarding the behavior of mercury in oligohaline wetland habitats, particularly with respect to edaphic and vegetative effects, through a monitoring and characterization study as well as a series of manipulative experiments. The observational study, conducted in the wetlands …

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Choosing Between Remote I/O Versus Staging In Distributed Environments, Ibrahim Hakki Suslu Jan 2010

Choosing Between Remote I/O Versus Staging In Distributed Environments, Ibrahim Hakki Suslu

LSU Doctoral Dissertations

Today, scientifi_x000C_c applications and experiments have become increasingly complex and more demanding in terms of their computational and data requirements. The amount of data generated and used has grown at a very rapid rate. As tens or hundreds of terabytes of data for a single application is very common today; petabytes and even exabytes of data will be very common in a few years. One of the major challenges in distributed computing environments is how to access these large datasets remotely over the network. Data staging and remote I/O are the most widely used data access methods for distributed applications. …

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Influences On Public Support For Green Infrastructure: An Examination Of Urban Wetland Restoration In Post-Katrina New Orleans, Lynette C. Overholser Jan 2010

Influences On Public Support For Green Infrastructure: An Examination Of Urban Wetland Restoration In Post-Katrina New Orleans, Lynette C. Overholser

LSU Master's Theses

The research examines patterns of likely support for urban wetland restoration in the Greater New Orleans area. Through multi-variate statistical analysis of responses derived from an original survey of homeowners in New Orleans, key factors are identified that explain variation in residents’ willingness to accept such areas and their perceptions of ecological benefits associated with a theoretical wetlands restoration design for the Gentilly area. Further, the analysis determines the extent to which direct experience with Hurricane Katrina may influence public support for this and other green infrastructure projects. The results of the data collected show that many people in New …

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Patterns Of Habitat Suitability And Abundance Trends Of Current And Candidate Coastal Fish Species Of Concern In Louisiana, Elin Rose Sandy Jan 2010

Patterns Of Habitat Suitability And Abundance Trends Of Current And Candidate Coastal Fish Species Of Concern In Louisiana, Elin Rose Sandy

LSU Master's Theses

Louisiana’s estuaries and coastal waters play an important role in providing habitat for several estuarine-dependent species and also serve as a nursery for the juveniles of several other species. The current rate of land loss in Louisiana and the decline of estuarine-dependent species force us to improve our understanding of the recruitment of these species into Louisiana’s estuaries. Habitat suitabilities were developed for several fish species of concern (SOC) and other estuarine-dependent species across three environmental gradients, abundance patterns were developed for seasons, five-year intervals, and coastal study areas (CSAs). Chi-square analyses and ANOVAs were then used to test for …

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Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron Jan 2010

Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron

LSU Doctoral Dissertations

Population growth for mallards (Anas platyrhynchos), and presumably other upland nesting ducks, in the Prairie Pothole Region is most sensitive to nest success, and nest success is most strongly influenced by predation. I evaluated the efficacy of reducing predator populations to improve nest success and increase local breeding populations of upland nesting ducks on township-sized (93.2 km2) management units in eastern North Dakota, USA, during 2005−2008. I also examined potential territorial limitations on local population growth for mallards. Trappers annually removed an average of 245 predators per trapped site. I monitored 7,489 nests on 7 trapped and 5 nontrapped sites, …

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Sonata No.1 For Violin And Piano, Op. 80,By Sergei Prokofiev: A Guide To Interpretation, Boris Blagoev Jan 2010

Sonata No.1 For Violin And Piano, Op. 80,By Sergei Prokofiev: A Guide To Interpretation, Boris Blagoev

LSU Doctoral Dissertations

Sergei Prokofiev was an extremely prolific composer whose career brought him success throughout Europe and the U. S. as well as Russia and the Soviet Union. He wrote for nearly every genre, and his most popular works today include operas, ballets, symphonies, and concertos. As a pianist, most of the concertos and sonatas that Prokofiev wrote were for the piano. However, his contributions to the violin repertoire are significant. Prokofiev wrote two concertos and two sonatas for solo violin. Of these, Sonata No. 1 for Violin and Piano, Op. 80 is unique for many reasons. The piece took Prokofiev eight …

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Joep Franssens' Harmony Of The Spheres: A Conductor's Analysis, David Andrew Hobson Jan 2010

Joep Franssens' Harmony Of The Spheres: A Conductor's Analysis, David Andrew Hobson

LSU Doctoral Dissertations

Harmony of the Spheres is Dutch composer Joep Franssens’ most extensive choral work to date, exhibiting a substantial possibility to enter the international repertoire as a complete work; however, several of the movements can stand alone effectively. Presented in five symmetrically conceived movements, Franssens scores the piece for SSAATTBB chorus with only the addition of full string orchestra for Movement III. The composition seeks to explore profound connections between science, music, philosophy, religion, and human relationships, intertwining excerpts from Benedict de Spinoza’s magnum opus, Ethica, allusions to the ancient idea of the music of the spheres, and European minimalism. Franssens …

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A Characterization Of Near Outer-Planar Graphs, Tanya Allen Lueder Jan 2010

A Characterization Of Near Outer-Planar Graphs, Tanya Allen Lueder

LSU Master's Theses

This thesis focuses on graphs containing an edge whose removal results in an outer-planar graph. We present partial results towards the larger goal of describing the class of all such graphs in terms of a finite list of excluded graphs. Specifically, we give a complete description of those members of this list that are not 2-connected or do not contain a subdivision of a three-spoke wheel. We also show that no members of the list contain a five-spoke wheel.

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Stochastic Trends In Crop Yield Density Estimation, David I. Maradiaga Jan 2010

Stochastic Trends In Crop Yield Density Estimation, David I. Maradiaga

LSU Master's Theses

The search for improved methods of estimating crop yield density functions has been a theme of recurrent research interest in agricultural economics. Crop yield density functions are the statistical instrument that generates probability estimates of yield risk, and risk is an important decision variable in production agriculture. Recent research in crop yield density estimation suggests that yield probability estimates can be sensitive to the way yield data are filtered, and if true, then the search for an “adequate filter” is warranted. Such a quest is pursued in this study. It is proposed that unit-root tests can be used to identify …

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Perverse Poisson Sheaves On The Nilpotent Cone, Jared Lee Culbertson Jan 2010

Perverse Poisson Sheaves On The Nilpotent Cone, Jared Lee Culbertson

LSU Doctoral Dissertations

For a reductive complex algebraic group, the associated nilpotent cone is the variety of nilpotent elements in the corresponding Lie algebra. Understanding the nilpotent cone is of central importance in representation theory. For example, the nilpotent cone plays a prominent role in classifying the representations of finite groups of Lie type. More recently, the nilpotent cone has been shown to have a close connection with the affine flag variety and this has been exploited in the Geometric Langlands Program. We make use of the following important fact. The nilpotent cone is invariant under the coadjoint action of G on the …

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Diatom Stratigraphy Defining Ice Sheet Grounding Chronology, Ross Sea, Antarctica, Juan Manuel Chow Jan 2010

Diatom Stratigraphy Defining Ice Sheet Grounding Chronology, Ross Sea, Antarctica, Juan Manuel Chow

LSU Doctoral Dissertations

Evidence of Antarctic ice sheet behavior and paleoenvironment is often approached from proxy records because there is a dearth of direct records from Antarctica itself. The studies presented here seek to augment our knowledge of translations of the West Antarctic Ice Sheet’s (WAIS) marine termination based on direct biostratigraphic evidence. Diatom analyses were conducted from two areas of Ross Sea, Antarctica. In the first study, diatoms were used to constrain the age of diamictons from five seismic units in the Eastern Basin and thus expand our knowledge of WAIS behavior during the Southern Hemisphere Last Glacial Maximum (LGM). All five …

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Effects Of Habitat Structural Complexity On Nekton Assemblages: Lab And Field Observations In Southern Louisiana, Austin T. Humphries Jan 2010

Effects Of Habitat Structural Complexity On Nekton Assemblages: Lab And Field Observations In Southern Louisiana, Austin T. Humphries

LSU Master's Theses

Greater structural complexity is often associated with more diverse and abundant species assemblages. Biogenic reefs formed by the eastern oyster (Crassostrea virginica) are structurally complex in nature and have been recognized for their potential habitat value in estuarine systems along the Atlantic and Gulf of Mexico coasts. To determine how the structural complexity of newly created oyster reefs may influence the abundance and distribution of species, three objectives were established. First, to examine spatial and temporal patterns of nekton use at newly created oyster reefs, as well as the impact of wave exposure, six paired oyster reef and mud-bottom treatments …

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Method Of Riemann Surfaces In Modelling Of Cavitating Flow, Anna Zemlyanova Jan 2010

Method Of Riemann Surfaces In Modelling Of Cavitating Flow, Anna Zemlyanova

LSU Doctoral Dissertations

This dissertation is concerned with the applications of the Riemann-Hilbert problem on a hyperelliptic Riemann surface to problems on supercavitating flows of a liquid around objects. For a two-dimensional steady irrotational flow of liquid it is possible to introduce a complex potential w(z) which allows to apply the powerful methods of complex analysis to the solution of fluid mechanics problems. In this work problems on supercavitating flows of a liquid around one or two wedges have been stated. The Tulin single-spiral-vortex model is employed as a cavity closure condition. The flow domain is transformed into an auxiliary domain with known …

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Planck Versus Poe: Scientific And Poetic Approaches, Anita Kelkar Jan 2010

Planck Versus Poe: Scientific And Poetic Approaches, Anita Kelkar

Quill & Scope

P A M Dirac wrote that "In science one tries to tell people, in such a way as to be understood by every- one, something that no one ever knew before. But in poetry, it’s the exact opposite." Dirac's quote con- fronts us with the question: Do both the scientific and poetic approaches ultimately enjoy equal success in expanding human knowledge?

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Nir Dyes For Bioimaging Applications, Jorge O. Escobedo, Oleksandr Rusin, Soojin Lim, Robert M. Strongin Jan 2010

Nir Dyes For Bioimaging Applications, Jorge O. Escobedo, Oleksandr Rusin, Soojin Lim, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Fluorescent dyes based on small organic molecules that function in the near infra red (NIR) region are of great current interest in chemical biology. They allow for imaging with minimal autofluorescence from biological samples, reduced light scattering and high tissue penetration. Herein, examples of ongoing NIR fluorophore design strategies as well as their properties and anticipated applications relevant to the bioimaging are presented.

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Implementation And Analysis Of A Top-K Retrieval System For Strings, Sabrina Chandrasekaran Jan 2010

Implementation And Analysis Of A Top-K Retrieval System For Strings, Sabrina Chandrasekaran

LSU Master's Theses

Given text which is a union of d documents of strings, D = d1, d2,...., dd, the emphasis of this thesis is to provide a practical framework to retrieve the K most relevant documents for a given pattern P, which comes as a query. This cannot be done directly, as going through every occurrence of the query pattern may prove to be expensive if the number of documents that the pattern occurs in is much more than the number of documents (K) that we require. Some advanced query functionality will be required, as compared to listing the documents that the …

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Multi-Scale Habitat Associations Of Shorebirds During Spring Migration In Southwestern Louisiana Rice Fields, Rachel K. Villani Jan 2010

Multi-Scale Habitat Associations Of Shorebirds During Spring Migration In Southwestern Louisiana Rice Fields, Rachel K. Villani

LSU Master's Theses

Rice is the most common wetland crop in the world, and important for waterbirds and shorebirds worldwide, including the United States. In Louisiana, shorebirds use rice fields during spring migration, and are an important for foraging and refueling during migration. However, competing land uses and restoration projects may reduce the availability of rice fields, and impact the landscape that shorebirds use during migration. To determine how shorebirds use the landscape, I evaluated local and landscape factors affecting shorebird use of rice fields during spring migration in southwestern Louisiana. Using five habitat suitability zones (HSZs) based on rice density and canopy …

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Homeopathy, Charles Volk Jan 2010

Homeopathy, Charles Volk

Quill & Scope

For the first 50 years of NYMC's history, the school taught a form of medicine called 'homeopathy'. What is this form of medicine and what would it be like to go to a homeopathic medical school? The author shares his experiences in the world of alternative medicine and the time he spent in a homeo- pathic academy learning about energy medicine, impossibly diluted compounds, how the germ theory is wrong, how science is incorrect, and how miasms are at the core of all human suffering.

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Oxidation Of Reduced Sulfur Compounds: A Triple-Oxygen-Isotope Perspective, Issaku E. Kohl Jan 2010

Oxidation Of Reduced Sulfur Compounds: A Triple-Oxygen-Isotope Perspective, Issaku E. Kohl

LSU Doctoral Dissertations

The Earth’s geochemical evolution is recorded in the rocks that compose its lithosphere. Specifically, sulfate minerals have been identified as being repositories of information concerning the past hydrosphere, atmosphere and biosphere. This is due to the non-labile nature of SO42- and its ability to store a record of the oxidative reactions and oxygen sources involved in its formation. Microbial dissimilatory sulfate reduction (MDSR) and sulfide oxidation cause oxygen from H2O and O2 to be trapped to varying degrees in ambient, dissolved SO42-. In order to better interpret the H2O and O2 signals in SO42-, we must deepen our understanding of …

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Carbon Nanotube Interconnect Modeling For Very Large Scale Integrated Circuits, Yao Xu Jan 2010

Carbon Nanotube Interconnect Modeling For Very Large Scale Integrated Circuits, Yao Xu

LSU Doctoral Dissertations

In this research, we have studied and analyzed the physical and electrical properties of carbon nanotubes. Based on the reported models for current transport behavior in non-ballistic CNT-FETs, we have built a dynamic model for non-ballistic CNT-FETs. We have also extended the surface potential model of a non-ballistic CNT-FET to a ballistic CNT-FET and developed a current transport model for ballistic CNT-FETs. We have studied the current transport in metallic carbon nanotubes. By considering the electron-electron interactions, we have modified two-dimensional fluid model for electron transport to build a semi-classical one-dimensional fluid model to describe the electron transport in carbon …

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Water And Solute Transport In The Shallow Subsurface Of A Riverine Wetland Natural Levee, April Elea Newman Jan 2010

Water And Solute Transport In The Shallow Subsurface Of A Riverine Wetland Natural Levee, April Elea Newman

LSU Master's Theses

In riverine wetlands, the rate and magnitude of water exchanged between river channels and adjacent wetlands have a major influence on hydrologic function and associated aquatic habitat and water quality. River channels are generally separated from backswamps by natural levees; however, preferential flow may allow potentially substantial water and solute exchange between them. Determining the influence of preferential flow on water and solute transport in natural levees requires an innovative approach that allows measurement of transport rates at a scale large enough to capture field-scale variability. To test the hypothesis that preferential flow is important to subsurface water movement through …

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Calibrating And Improving The Sensitivity Of The Ligo Detectors, Jeffrey S. Kissel Jan 2010

Calibrating And Improving The Sensitivity Of The Ligo Detectors, Jeffrey S. Kissel

LSU Doctoral Dissertations

The Laser Interferometer Gravitational wave Observatory (LIGO) is network of three, power recycled Fabry-Perot Michelson interferometers built to detect gravitational waves from astrophysical sources at frequencies between 40 and 6000 Hz. For their fifth science run, from 2005 to 2007, the detectors observed at designed sensitivity, achieving equivalent strain amplitude noise of 3x10^−23 strain/rtHz at 100 Hz. To date, the observatory has not detected gravitational waves. However, even at such sensitivity, the expected detection rate for known astrophysical sources of gravitational waves is likely 0.02 yr^−1. The fundamental noise source of these ground-based detectors limiting the sensitivity below 40 Hz …

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The Care Plan As An Indicator Of Change In Nursing Science Instruction: A Textbook-Based Analysis, Lindsay Bratton-Mullins Jan 2010

The Care Plan As An Indicator Of Change In Nursing Science Instruction: A Textbook-Based Analysis, Lindsay Bratton-Mullins

LSU Doctoral Dissertations

Sciences are critical in nursing education to aid the nurse in understanding health and disease processes. Accrediting bodies for nursing education have emphasized that educators teach in ways that encourage critical thinking and, therefore, produce safe-practicing, competent nurse graduates. Nursing care plans best reflect nursing education’s central goals. Because of its longevity of use and familiarity, in this study, the nursing care plan was used as a proxy for nursing science’s learning objectives. This research was a study of the nursing care plan as an indicator for change in nursing science education in the United States to determine if change …

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Investigating The Ironwood Tree (Casuarina Equisetifolia) Decline On Guam Using Applied Multinomial Modeling, Karl Anthony Schlub Jan 2010

Investigating The Ironwood Tree (Casuarina Equisetifolia) Decline On Guam Using Applied Multinomial Modeling, Karl Anthony Schlub

LSU Master's Theses

The ironwood tree (Casuarina equisetifolia), a protector of coastlines of the sub-tropical and tropical Western Pacific, is in decline on the island of Guam where aggressive data collection and efforts to mitigate the problem are underway. For each sampled tree the level of decline was measured on an ordinal scale consisting of five categories ranging from healthy to near dead. Several predictors were also measured including tree diameter, fire damage, typhoon damage, presence or absence of termites, presence or absence of basidiocarps, and various geographical or cultural factors. The five decline response levels can be viewed as categories of a …

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Landscape Patterns Of Community Structure, Biomass And Net Primary Productivity Of Mangrove Forests In The Florida Coastal Everglades As A Function Of Resource, Regulators, Hydroperiod, And Hurricane Distrubance, Edward Castaneda Jan 2010

Landscape Patterns Of Community Structure, Biomass And Net Primary Productivity Of Mangrove Forests In The Florida Coastal Everglades As A Function Of Resource, Regulators, Hydroperiod, And Hurricane Distrubance, Edward Castaneda

LSU Doctoral Dissertations

Spatial and temporal patterns of mangrove vegetation in the Florida Coastal Everglades (FCE) reflect a major interplay of resources, regulators and hydroperiod gradients. I investigated landscape patterns of community structure, biomass and NPP of mangroves along two FCE estuaries: Shark River and Taylor River. I also evaluated whether pulsing events such as Hurricane Wilma are significant to soil nutrient inventories and vertical accretion of mangroves in FCE. There was a higher forest structural complexity of mangroves in Shark River relative to Taylor River. The biomass root:shoot ratio was 17 times higher in Taylor River relative to Shark River, indicating that …

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