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Full-Text Articles in Physical Sciences and Mathematics

Some Effects Of Nutrient And Flooding Stress Manipulation On Coastal Louisiana Wetland Vegetation, James Stephen Ialeggio Jan 2013

Some Effects Of Nutrient And Flooding Stress Manipulation On Coastal Louisiana Wetland Vegetation, James Stephen Ialeggio

LSU Master's Theses

Freshwater diversions are a relatively recently utilized tool in wetland loss mitigation that stimulate an organic accretion response in marsh vegetation, which is based in root production and thus belowground biomass. The effectiveness of freshwater diversions in slowing marsh loss probably varies across a gradient of the factors they supply: decreased salinity, increased nutrient concentrations, and increased inundation. Flooding stress is commonly thought to be the overriding factor limiting wetland vegetation growth, however its influence may vary across salinity and nutrients. Therefore, plugs of Spartina patens were planted in four “marsh organs” consisting each of 36 sediment-filled PVC pipes of …


Effects Of Physicochemical Properties And Macrohabitat On The Foraging Ecology And Condition Of The Centrarchid Assemblage Of The Atchafalaya River Basin, Louisiana, Brett A. Miller Jan 2013

Effects Of Physicochemical Properties And Macrohabitat On The Foraging Ecology And Condition Of The Centrarchid Assemblage Of The Atchafalaya River Basin, Louisiana, Brett A. Miller

LSU Master's Theses

The Atchafalaya River Basin (ARB), Louisiana supports a diverse centrarchid assemblage, characterized by abundant populations of largemouth bass Micropterus salmoides, black crappie Pomoxis nigromaculatus, warmouth Lepomis gulosus, bluegill Lepomis macrochirus, redspotted sunfish Lepomis miniatus, longear sunfish Lepomis megalotis and redear sunfish Lepomis microlophus. This dynamic floodplain ecosystem is comprised of a mosaic of macrohabitats, including natural bayous, shallow lakes, dead-end and open pipeline canals. I conducted an extensive feeding ecology study to determine the influence of these macrohabitats on foraging activity through stomach content and stable isotope analyses. I collected 2,036 centrarchids with electrofishing efforts in the summers of 2011 …


Population Ecology Of The Ribbed Mussel In Southeastern Louisiana, Aaron Jacob Honig Jan 2013

Population Ecology Of The Ribbed Mussel In Southeastern Louisiana, Aaron Jacob Honig

LSU Master's Theses

Benthic intertidal bivalves play an essential role in estuarine ecosystems by contributing to habitat provision, water filtration, and promoting productivity. As such, ecosystem level changes that impact population distributions and persistence of local bivalve populations may have large ecosystem level consequences, making it important to better understand the population distribution and ecology of native bivalve populations. Gametogenesis, recruitment, growth, mortality, size structure and density of the ribbed mussel, Geukensia demissa, were examined across a salinity gradient in southeastern Louisiana. In summer 2012, 100-m transects were placed at interior and edge marsh plots to collect data on mussel density, and vegetation …


Community Resilience To Coastal Hazards : An Analysis Of Two Geographical Scales In Louisiana, Chi Li Jan 2013

Community Resilience To Coastal Hazards : An Analysis Of Two Geographical Scales In Louisiana, Chi Li

LSU Master's Theses

Quantifying resilience is difficulties due to the different definitions of resilience, the interchangeable uses with two other terms “vulnerability” and “adaptability”, as well as the lack of consensus on what indicators should be selected to quantifying resilience. This thesis research studied the community resilience in Louisiana by applying the Resilience Inference Measurement (RIM) model at two geographic levels: county level and zip code level. The RIM model accesses resilience by using three dimensions (exposure, damage, and recovery) and two abilities (vulnerability and adaptability). The types of coastal hazards included in this study were: coastal, flooding, hurricane/tropical storm, tornado, and severe …


Hydraulic Fracturing And Water Use In Dallas, Texas, Sarah Yates Jan 2013

Hydraulic Fracturing And Water Use In Dallas, Texas, Sarah Yates

LSU Master's Theses

Dallas, Texas is located in North Texas and sits above the eastern portion of the Barnett Shale natural gas formation. Hydraulic fracturing, or “fracking”, was introduced to the region as a means to access previously inaccessible natural gas within the formation. This fracking concerns many because it requires large amounts of fresh water, an average of over 4 million gallons per well within Dallas Water Utilities’ service area. This thesis examines whether water use for fracking will have a negative effect on the water supply for the city of Dallas and its wholesale water customer cities. The water is typically …


Effects Of Predator Reduction On Nest Success Of Upland Nesting Ducks In Low-Grassland Density Landscapes In Eastern North Dakota, Michael Buxton Jan 2013

Effects Of Predator Reduction On Nest Success Of Upland Nesting Ducks In Low-Grassland Density Landscapes In Eastern North Dakota, Michael Buxton

LSU Master's Theses

Nest success of upland nesting ducks is the primary driver of duck population growth in the Prairie Pothole Region. Nest success is greatly influenced by nest predation and the amount of available nesting cover on the landscape. The decline in acres enrolled in the Conservation Reserve Program (CRP) in this region has negatively impacted the amount of available nesting cover, making nesting cover sparse and confined to small patches where predation rates are potentially elevated. I evaluated the efficacy of seasonal predator reduction on increasing nest success on low-grassland density (>10% grassland cover), 93 km2 landscapes in two different …


An Evaluation Of Oyster Stocks, Grow-Out Conditions, And Off-Bottom Culture Methods For Increasing Commercial Production Of Eastern Oysters (Crassostrea Virginica) In The Northern Gulf Of Mexico, Justin Morgan Leonhardt Jan 2013

An Evaluation Of Oyster Stocks, Grow-Out Conditions, And Off-Bottom Culture Methods For Increasing Commercial Production Of Eastern Oysters (Crassostrea Virginica) In The Northern Gulf Of Mexico, Justin Morgan Leonhardt

LSU Master's Theses

This project examined the ecologically and economically valuable eastern oyster (Crassotrea virginica) in Louisiana with two field experiments. Little information has been gathered on the performance of local Louisiana oyster stocks and no study has focused on a comparison of stocks among variable estuarine conditions. Additionally, the use of alternative grow-out methods and intensive cage aquaculture has never been evaluated in Louisiana. For the first study, a dermo-resistant stock of oysters (LSU-OYS: ‘OBOY’) was compared to three wild oyster stocks along a salinity gradient. The objectives of this study were to determine the optimal oyster stock(s) and the ideal grow-out …


Predicting Mechanical Properties Of Southern Pine Lumber With Nondestructive Measurements, Jacob Romer Jan 2013

Predicting Mechanical Properties Of Southern Pine Lumber With Nondestructive Measurements, Jacob Romer

LSU Master's Theses

Predictive models were developed for stiffness and bending strength of southern pine 2x6, eight ft. lumber using nondestructive measurements of stresswave velocity, density and visual characteristics such as knots, slope of grain and rate of growth. To account for local areas of weakened material due to knots and slope of grain, a grid system was developed to quantify general knot size and location. Multiple regression models were created using these physical and visual measurements. Two sets of models were developed: one that removed influential samples with abnormal wavespeeds (greater than 18,000 ft./s) indicative of poor wood quality; and, models that …


Impacts And Recovery Of The Deepwater Horizon Oil Spill On Vegetation Structure And Function Of Phragmites Australis, Chad Robert Judy Jan 2013

Impacts And Recovery Of The Deepwater Horizon Oil Spill On Vegetation Structure And Function Of Phragmites Australis, Chad Robert Judy

LSU Master's Theses

Abstract The aim of this study was to determine the impacts of the Deepwater Horizon (DWH) oil spill on the common reed Phragmites australis, and the processes controlling species effects and recovery, via a greenhouse mesocosm study. In the greenhouse DWH source oil, weathered approximately 40% by weight and emulsified, was applied to the aboveground shoots of P. australis growing in marsh sods to produce the following treatment-levels: (1) oil coverage of the lower 30% of shoot-height, (2) the lower 70% of shoot-height, (3) repeated oil coverage of the lower 70% of shoot-height, (4) 100% oil coverage of shoots, (5) …


Long-Term Total Suspended Sediment Yield Of Coastal Louisiana Rivers With Spatiotemporal Analysis Of The Atchafalaya River Basin And Delta Complex, Timothy Rosen Jan 2013

Long-Term Total Suspended Sediment Yield Of Coastal Louisiana Rivers With Spatiotemporal Analysis Of The Atchafalaya River Basin And Delta Complex, Timothy Rosen

LSU Master's Theses

The modern day Mississippi River Delta Plain and the Louisiana Chenier Plain have been greatly altered through anthropogenic changes to course and hydrological conditions of the Mississippi River and local rivers, most notably by levees that have excluded the Mississippi River from the delta plain. This has slowed accretion and increased land loss destroying vast quantities of marsh, endangering many coastal communities. This master’s thesis examined long-term total suspended sediment yield of four Chenier Plain rivers, total suspended sediment yield of the Mississippi River under different flow conditions, and total suspended sediment dynamics of the Atchafalaya River in relation to …


An Analysis Of Cardiovascular And Respiratory Admission Rates As A Function Of Air Pollutants In The Baton Rouge Five-Parish Area, Heather Elizabeth Spindel Jan 2013

An Analysis Of Cardiovascular And Respiratory Admission Rates As A Function Of Air Pollutants In The Baton Rouge Five-Parish Area, Heather Elizabeth Spindel

LSU Master's Theses

In past years, the Baton Rouge Air Quality Control Region has struggled with compliance of ozone standards. In June of 2003, the Baton Rouge Five-Parish Ozone Non-Attainment Area was classified as severe under the 1-hour ozone standard. In July of 2012, the EPA classified the area as marginal non-attainment for ozone. Although this is an improvement from its severe classification, studies have shown that health effects of air pollution can be detected at concentrations lower than the National Ambient Air Quality Standards. Additionally, clinical and epidemiological studies have shown that a majority of the criteria pollutants negatively affect cardiovascular and …


Effects Of Deepwater Horizon Oil On The Growth Rates And Pigment Composition Of Phytoplankton Isolated From Grand Isle, La, Jie Li Jan 2013

Effects Of Deepwater Horizon Oil On The Growth Rates And Pigment Composition Of Phytoplankton Isolated From Grand Isle, La, Jie Li

LSU Master's Theses

This research focused on the effects of un-weathered Macondo crude oil on the growth rates and pigment ratios of phytoplankton isolated from Grand Isle, LA. The experiments involved incubating nutrient-enriched artificial media containing a range of oil concentrations up to 19.2 ppm with small aliquots of coastal water from Grand Isle and measuring the growth rates of the phytoplankton during the subsequent 10–14 days and the pigment ratios of the phytoplankton at the end of log-phase growth to determine whether the crude oil affected the growth rate of the phytoplankton and their composition in terms of pigment ratios. Pigment analysis …


An Analysis Of The Influences On Household-Level Adaptations To Environmental Hazards, Tiia Maria Carraway Jan 2013

An Analysis Of The Influences On Household-Level Adaptations To Environmental Hazards, Tiia Maria Carraway

LSU Master's Theses

Utilizing a randomized phone survey of coastal Louisiana residents, this study will focus on identifying which influences from a resident’s exposure, socio-economic vulnerability and adaptive capacity are the best indicators of an individual’s resilience. Two binary logistic regression models were developed to test the associations of resident response to: 1) acute hazards via household emergency plan adoption and 2) chronic hazards represented by behavior modification in response to daily air quality reporting where adoption of these two risk-reducing behaviors are viewed as increased individual resilience. Bivariate correlation analysis found that a north – south grouping of coastal Louisiana was significantly …


An Analysis Of The Allocation Of Fema Public Assistance Funds Along The U.S. Gulf Coast Following Hurricanes Katrina, Rita, And Wilma, Pamela Camille Golden Jan 2013

An Analysis Of The Allocation Of Fema Public Assistance Funds Along The U.S. Gulf Coast Following Hurricanes Katrina, Rita, And Wilma, Pamela Camille Golden

LSU Master's Theses

Due to the effects of global climate change, natural disasters such as hurricanes are increasing in terms of both intensity and frequency. During the record-breaking hurricane season of 2005, Hurricanes Katrina, Rita, and Wilma struck the U. S. Gulf Coast, affecting areas from Texas to Florida and causing billions of dollars in damage. This study examines the allocation of FEMA Public Assistance across the affected Gulf of Mexico states, what factors account for variation in in assistance allocation, what are the priorities for recovery among county leaders and what obstacles they have encountered since 2005. This study includes 136 counties …


An Analysis Of The Prevalence Of The West Nile Virus In Relation To Health Resilience Along The Gulf Of Mexico, Lillian Patricia Mata Jan 2013

An Analysis Of The Prevalence Of The West Nile Virus In Relation To Health Resilience Along The Gulf Of Mexico, Lillian Patricia Mata

LSU Master's Theses

As the Earth’s climate changes, coastal communities are increasingly vulnerable to the natural hazards that are driven by these processes, particularly in regards to the health of these communities. It has been shown that disease patterns can change in response to our environment, putting the health resilience of communities at risk. This study looks at the relationship between natural exposure and traditional resilience index variables in the context of the spread of West Nile Virus along the Gulf of Mexico. Through analysis of 534 counties, the West Nile Virus for 2001-2012 was analyzed as an incidence and incidence rate at …


Fish And Macroinvertebrate Assemblage Composition And Diversity At Revetted Banks In The Pearl River And The Response Of These Assemblages To A Paper Mill Effluent Spill, Jose Alexander Vazquez Jan 2013

Fish And Macroinvertebrate Assemblage Composition And Diversity At Revetted Banks In The Pearl River And The Response Of These Assemblages To A Paper Mill Effluent Spill, Jose Alexander Vazquez

LSU Master's Theses

The armoring of river banks with riprap can have detrimental effects on lotic ecosystems due to the subsequent alteration of hydrologic regimes; however, evidence suggests that riprap can also increase aquatic diversity in degraded systems. The goal of my study was to determine what impacts riprapped banks have on fish and macroinvertebrate assemblages in the Pearl River, which has a history of anthropogenic degradation. I collected fishes with an electrofishing boat from armored and natural banks at five regions during fall 2011, winter 2012, and summer 2012. I also collected macroinvertebrates with introduced substrates in fall 2011. Richness was analyzed …


Leadership In Environmental And Energy Design : A True Sustainable Development Model?, Christopher Jay Loser Jan 2013

Leadership In Environmental And Energy Design : A True Sustainable Development Model?, Christopher Jay Loser

LSU Master's Theses

Suburban sprawl and sustainable development has received increasing worldwide attention over the past few decades. In 1998, sustainable development principles were codified in the Leadership in Energy and Environmental Design (LEED) certification system. The most recent LEED certification system to be released, LEED for New Development (LEED-ND), includes sustainable development goals with the addition of smart growth principles intended to curb sprawl. This study examines and evaluates LEED-ND in order to determine if it meets the requirements of sustainable development to provide for the needs of future generations, as defined by the United Nation’s World Commission on Environment and Development. …


Monitoring The Survival Of Hatchery-Produced Spat And Larvae On Louisiana Public Oyster Reefs, Erin R. Leonhardt Jan 2013

Monitoring The Survival Of Hatchery-Produced Spat And Larvae On Louisiana Public Oyster Reefs, Erin R. Leonhardt

LSU Master's Theses

Alternative or supplemental management activities may be necessary to restore and enhance oyster production on Louisiana public oyster reefs. The production of wild oysters is variable due to anthropogenic and environmental factors that affect recruitment, growth and survival. The availability and structure of cultch material for larval recruitment and survival is particularly important to maintain oyster production. Beginning in 2011, the Sea Grant Oyster Hatchery on Grand Isle, LA and the Louisiana Department of Wildlife and Fisheries (LDWF) collaborated to test the survival of hatchery-produced spat and hatchery-produced larvae deployed on public oyster grounds and cultch plant sites. In 2011, …


Renewable Energy Across The 50 United States And Related Factors, Cynthia Brit Christenson Jan 2013

Renewable Energy Across The 50 United States And Related Factors, Cynthia Brit Christenson

LSU Master's Theses

Renewable energy production replaces diminishing non-renewable energy sources including fossil fuels. Major sources of renewable energy include biofuels, geothermal, hydroelectric, solar thermal and photovoltaic, wind, wood, and biomass. Greater use of renewable energy sources can fill gaps in energy as non-renewable sources are depleted, provide more energy independence at a state and national level, and help address climate change by reducing greenhouse gas emissions from combustion of fossil fuels. The research objectives of this thesis are two-fold. First, which U.S. states are leaders in renewable energy production? Second, what factors may account for variation among U.S. states in levels of …


Inductivley Coupled Plasma Optical Emission Spectroscopy Analysis Of Heavy Metal Concentrations In Gulf Menhaden (Brevoortia Patronus) Populations In The Northern Gulf Of Mexico From 2011 To 2012, Hannah Paula Rockett Jan 2013

Inductivley Coupled Plasma Optical Emission Spectroscopy Analysis Of Heavy Metal Concentrations In Gulf Menhaden (Brevoortia Patronus) Populations In The Northern Gulf Of Mexico From 2011 To 2012, Hannah Paula Rockett

LSU Master's Theses

In 2010, the Deepwater Horizon (DWH) oil spill, released 4.9 million barrels of oil into the Gulf of Mexico, creating the largest marine oil spill in the history of the U.S. petroleum industry. Trace metals, including those from crude oil, were dispersed in the water column and bound to suspended particulates. As obligate filter-feeding omnivores and a predominate fishery in the Gulf of Mexico, Gulf menhaden (Brevoortia patronus) are susceptible to trace metal accumulation. Samples of menhaden were collected at two locations in coastal Louisiana, Grand Isle (GI) and Vermillion Bay (VB), with VB serving as the non-impacted DWH oil …


Evaluating Abiotic Influences On Soil Salinity Of Inland Managed Wetlands And Agricultural Fields In A Semi-Arid Environment, Drew Nathan Fowler Jan 2013

Evaluating Abiotic Influences On Soil Salinity Of Inland Managed Wetlands And Agricultural Fields In A Semi-Arid Environment, Drew Nathan Fowler

LSU Master's Theses

Agriculture and moist-soil management are important management techniques used on wildlife refuges to provide adequate energy for migrant and wintering waterbirds. However, in arid systems, the presence and accumulation of soluble salts throughout the soil profile can limit total biomass production of wetland plants and agronomic crops and thus jeopardize meeting waterbird energy needs. It is unknown how moist-soil management and traditional agriculture practices influence the accumulation and distribution of soluble salts of soil profiles. In this study of an arid wetland ecosystem, I determine: 1) the effect of long-term, distinct surface hydrologic regimes associated with moist-soil management and agricultural …


Quantification Of Total And Oil-Degrading Bacteria In Louisiana Marsh Sediment Following The Deepwater Horizon Oil Spill Using Cultivation And Real-Time Pcr Assays, Kristopher Nolan Ackoury Jan 2013

Quantification Of Total And Oil-Degrading Bacteria In Louisiana Marsh Sediment Following The Deepwater Horizon Oil Spill Using Cultivation And Real-Time Pcr Assays, Kristopher Nolan Ackoury

LSU Master's Theses

Although the impacts of the Deepwater Horizon (DWH) oil spill on the bacterial communities in several Gulf of Mexico habitats have been described, little if any research has been published evaluating the impacts of the spill on bacterial populations in the most severely oiled salt marsh soils of Barataria Bay, Louisiana. The aim of this study was to define the effects of the spill on the total and oil-degrading bacterial communities in these marshes. Using quantitative real-time PCR (qPCR) and traditional cultivation methods bacterial communities from contaminated marsh soils were examined thirteen, twenty-two, and twenty-nine months after the initial oiling …


Bachman's Sparrow (Peucaea Aestivalis) Population Structure Across The Southeastern Usa, Blain Annette Cerame Jan 2013

Bachman's Sparrow (Peucaea Aestivalis) Population Structure Across The Southeastern Usa, Blain Annette Cerame

LSU Master's Theses

Understanding gene flow and population structure in wildlife populations helps managers to protect distinct genetic lineages and genetic variation in small, isolated populations at high risk of extinction. I assessed genetic diversity in Bachman’s Sparrows (Peucaea aestivalis) to evaluate the role of natural barriers in shaping evolutionarily significant units as well as the effect of anthropogenically-caused habitat loss and fragmentation on population differentiation and diversity. Genetic diversity was assessed across the geographic range of Bachman’s Sparrow by genotyping 226 individuals at 18 microsatellite loci and sequencing 48 individuals at nuclear and mitochondrial DNA genes. Multiple analyses consistently demonstrated high levels …