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Demographic Impacts Of Climate-Induced Migration And Environmental Shocks And Stressors In Cameron Parish, Louisiana, John Green Iii Nov 2020

Demographic Impacts Of Climate-Induced Migration And Environmental Shocks And Stressors In Cameron Parish, Louisiana, John Green Iii

Honors Theses

No abstract provided.


The Life History And Population Dynamics Of Southern Flounder, Kenneth A. Erickson Oct 2020

The Life History And Population Dynamics Of Southern Flounder, Kenneth A. Erickson

LSU Master's Theses

Southern Flounder, Paralichthys lethostigma, are a coastal, estuarine-dependent flatfish species that inhabits the Southeastern US Atlantic Ocean and Gulf of Mexico. Throughout their range, Southern Flounder are exploited by both commercial and recreational fisheries. Recently, numerous sources have expressed concerns about Southern Flounder populations, with stock assessments indicating declines in spawning stock biomass and recruitment. To estimate life history traits needed for informed management, such as age, growth, and maturity, I collected 327 Southern Flounder from Louisiana and obtained 14,184 historical records from the Louisiana Department of Wildlife and Fisheries. Using a von Bertalanffy growth equation in a Bayesian …


Seasonal Infilling And Sedimentary Characteristics In Sandy Versus Muddy Coastal Borrow Areas On The Louisiana Continental Shelf, Usa, Matthew Barley Aug 2020

Seasonal Infilling And Sedimentary Characteristics In Sandy Versus Muddy Coastal Borrow Areas On The Louisiana Continental Shelf, Usa, Matthew Barley

LSU Master's Theses

Offshore sand deposits on the Louisiana Continental Shelf, such as inner shelf shoals and buried paleo-river channels, can be excavated to restore beaches and barrier islands that are rapidly deteriorating due to subsidence, sea-level rise and deficits in coastal sediment supply. Presented here is grain size, x-radiograph, and Beryllium-7 (7Be) derived sedimentation rates from multicores (~ 50 cm depth) retrieved from borrow areas (BAs) in contrasting depositional settings, all of which have implications for management of water quality, seafloor sedimentology, and biogeochemistry in proximal areas. Multicores were retrieved in fall 2018 at Caminada BA — a sandy energetic …


Phosphorus Variability In The Area Of Influence Of The Mid-Barataria Sediment Diversion, Peter Mates Jul 2020

Phosphorus Variability In The Area Of Influence Of The Mid-Barataria Sediment Diversion, Peter Mates

LSU Master's Theses

Man-made levees along the lower Mississippi River prevent delivery of sediment from building and maintaining Louisiana’s coastal wetlands. The Mid-Barataria sediment diversions is designed to reintroduce Mississippi River water, sediment, and nutrients into the sediment-starved Barataria Basin. Phosphorus (P) is an important macronutrient for regulating primary production in coastal marine ecosystems. Wetlands can serve as a sink or source for phosphorus to the overlying water column through various retention and release processes, dependent on concentration. Louisiana coastal systems can be phosphorus limited due to much higher concentrations of bioavailable Nitrogen in river water. The high soluble molar N:P ( >50:1) …


Characterization Of Shallow Subsurface Hydrology In Large Fine-Grained Floodplains, Mary Grace Lemon Jul 2020

Characterization Of Shallow Subsurface Hydrology In Large Fine-Grained Floodplains, Mary Grace Lemon

LSU Doctoral Dissertations

Floodplains are hydrologically dynamic, receiving water from overbank events, hyporheic flows, local precipitation, and regional groundwater sources. These sources are variously important contributors to the heterogeneous floodplain water pool that includes matrix water in soil micropores, mobile water in soil macropores, groundwater below the rooting zone, ephemeral to seasonal surface storage, and permanent surface water features such as oxbow lakes, sloughs, and other secondary channels. All sources may be ecologically relevant for floodplain vegetation, but the exact roles of each source in both controlling soil water and shallow groundwater recharge and in controlling floodplain water drainage are not well understood, …


Identification And Quantification Of Microplastic Pollution In Water Samples And Four Species Of Fish From The Mississippi River, Kerrin E. Toner Jul 2020

Identification And Quantification Of Microplastic Pollution In Water Samples And Four Species Of Fish From The Mississippi River, Kerrin E. Toner

LSU Master's Theses

Microplastics (£5 mm) have become a persistent anthropogenic pollutant and a growing environmental concern with evidence of them being found throughout several ecosystems. In recent years, there has been a growing recognition that rivers play a major role in transporting plastics from the land to the sea. The Mississippi River is the largest river in North America, draining land populated by over 100 million people. With high numbers of microplastics found in the waters of the northern of the Gulf of Mexico, it is likely that the Mississippi River is the primary source of these plastics. This study quantifies and …


Seasonal Transport Of Dissolved Inorganic Carbon And Total Alkalinity Across The Louisiana Shelf, Michelle M. Anderson Jun 2020

Seasonal Transport Of Dissolved Inorganic Carbon And Total Alkalinity Across The Louisiana Shelf, Michelle M. Anderson

LSU Master's Theses

Rivers and wetlands are a major source of terrestrial derived carbon for coastal ocean margins. Unfortunately, Louisiana’s wetlands are threatened by ongoing high rates of erosion, deterioration, and unprecedented rates of river water discharge that changes seasonally, leading to a net loss of terrestrial carbon into the northern Gulf of Mexico (nGOM). There exists a current lack of understanding about the distribution of dissolved inorganic carbon (DIC) and total alkalinity (TAlk) within the shallowest regions of the Louisiana shelf. Even less is known about how the transport of DIC alters seasonally with changes in river outflow and shelf currents. Quantifying …


Estimating The Onset And Extent Of Dieback Of Phragmites Australis Using The Normalized Difference Vegetation Index And Remotely Sensed Land Cover Classifications, Aimee M. Beaudette Jun 2020

Estimating The Onset And Extent Of Dieback Of Phragmites Australis Using The Normalized Difference Vegetation Index And Remotely Sensed Land Cover Classifications, Aimee M. Beaudette

LSU Master's Theses

Phragmites australis is cosmopolitan plant species with an invasive variety present throughout most of North America. In the Balize Delta, Louisiana, USA, P. australis plays an important role in combatting subsidence, maintaining navigation channels, and protecting interior fish and wildlife habitat from waves and storm surge. In 2016 a dieback of P. australis was reported by wetland managers, coinciding with the appearance of an invasive Asian scale insect (Nipponaclerda biwakoensis), though the specific cause is still unknown. Two previous efforts attempted to identify the onset of dieback conditions met with limited success. Using Landsat images from 1985 to …


Microplastics In Mississippi River Fishes: A Watershed Approach, Ahmed Gad Jun 2020

Microplastics In Mississippi River Fishes: A Watershed Approach, Ahmed Gad

LSU Master's Theses

Microplastics are plastic particles less than 5mm that come from different sources, such as industrial products, cosmetics, and the breakdown of the macroplastics. Microplastics derive from terrestrial sources but concentrate in flowing freshwaters where they may enter aquatic food webs. The northern Gulf of Mexico has shown very high microplastic concentrations, which are assumed to be sourced from the Mississippi River and its watershed. This study seeks to study microplastics in fish in the Mississippi River and the Gulf of Mexico. Fish stomachs and intestines from fish underwent chemical digestion, filtration, and microplastics identification and enumeration through FT-IR spectrometry. Chapter …


Techno-Economic Analysis Of Floating Offshore Airborne Wind Energy Systems In The Gulf Of Mexico, Alexandria Savannah Leake Jun 2020

Techno-Economic Analysis Of Floating Offshore Airborne Wind Energy Systems In The Gulf Of Mexico, Alexandria Savannah Leake

LSU Master's Theses

Techno-economic analyses play an important role in determining locations for conventional wind turbine installations. This method is utilized to assess energy production potential for a new type of wind technology, known as airborne wind energy (AWE). The first objective of the present thesis was to determine overall investment potential of a utility-scale floating offshore airborne wind farm, testing five floating platform design concepts. The second objective was to determine whether the wind resources (100-1500 m) are ideal to support AWE systems in the Gulf of Mexico. Specifically, a hypothetical benchmark wind farm was developed 15 km offshore from Venice, Louisiana. …


The Siltcatcher: A Sediment-Capture System For Wetland Creation And Coastal Protection In Western Lake Pontchartrain, Andrew M. Wright Apr 2020

The Siltcatcher: A Sediment-Capture System For Wetland Creation And Coastal Protection In Western Lake Pontchartrain, Andrew M. Wright

LSU Master's Theses

The West Lake Pontchartrain region faces a number of long-term environmental challenges due to anthropogenic climate disturbance and landscape modification, including sea level rise, increased storm surge risk, shoreline erosion, and wetland degradation. In response, this thesis applies recent research in the fields of landscape architecture and civil engineering to propose a dynamic, natural-systems solution for wetland creation and shoreline protection. The project envisions a series of breakwater-like structures in western Lake Pontchartrain positioned to slow water released from the nearby Bonnet Carré Spillway, causing suspended sediment to settle and create self-building and self-sustaining wetlands capable of keeping pace with …


An Ecopath With Ecosim Analysis On Offshore Petroleum Platform Influences On Gulf Of Mexico Red Snapper, Valentin Gomez Apr 2020

An Ecopath With Ecosim Analysis On Offshore Petroleum Platform Influences On Gulf Of Mexico Red Snapper, Valentin Gomez

LSU Master's Theses

Offshore oil and gas platforms have had a significant presence in the Gulf of Mexico since the 1950s. An important secondary function of these structures is that they provide artificial habitat to fisheries, most notably Red snapper. Policy changes intended to reduce the risk associated with aging infrastructure have reduced the number of standing platforms from 4044 to 1867 from 2001 to 2018. The effect this loss of habitat has on Red snapper was tested by creating three scenarios of platform changes and modeling the perturbation from 2005 to 2050. The simulation was accomplished using the ecological model Ecopath with …


Biogeography Of Biological Control: Spatial Variation In Agent-Host Interactions, Nathan Harms Apr 2020

Biogeography Of Biological Control: Spatial Variation In Agent-Host Interactions, Nathan Harms

LSU Doctoral Dissertations

Management of plant invasions using biological control has the potential to generate spatial patterns which reflect geographic or genetic variation in invader or control agents. Despite its rarity in practice, investigations into the biogeography of interacting species (i.e., plant invader and control agent) in the context of biological control can lend insights into species distribution-abundance patterns and provide predictions for spatial variation in control success. I explored spatial variability in biological control agent-plant interactions using two wetland weed study systems with large geographic distributions: flowering rush (Butomus umbellatus L.) and alligatorweed (Alternanthera philoxeroides (Mart.) Griseb). Through literature and …


Evaluation Of Neutron Skyshine Contributions During Injection At An Electron Synchrotron Facility Using Fluka, Andrew D. Hastings Apr 2020

Evaluation Of Neutron Skyshine Contributions During Injection At An Electron Synchrotron Facility Using Fluka, Andrew D. Hastings

LSU Master's Theses

The Center for Advanced Microstructures and Devices (CAMD) is a 1.5 giga-electron volt (GeV) electron synchrotron research facility under the jurisdiction of Louisiana State University (LSU). When originally constructed in 1992, CAMD was surrounded by pasture and woodland. Over the past several years, urban development of the area has found CAMD bracketed by a shopping center, apartment complex, and business offices. These developments raised concerns amongst the CAMD radiation safety personnel regarding an increased potential for public exposure to radiation. To ensure compliance with the annual public effective dose equivalent limit of 1 milli-sievert (mSv), the radiation monitoring program was …


Dissipation Of Benzobicyclon And Benzobicyclon Hydrolysate In A Louisiana Rice Field, Xavier Poole Mar 2020

Dissipation Of Benzobicyclon And Benzobicyclon Hydrolysate In A Louisiana Rice Field, Xavier Poole

LSU Master's Theses

Pesticide resistance in rice fields is an ongoing issue that has resulted in the development and use of pesticides with new modes of action. Benzobicyclon is the first registered hydroxyphenylpyruvate(HPPD)-inhibiting pesticide in the United States and has gained attention as a resistance management strategy to control weed pests in rice fields. Understanding the environmental fate and dissipation mechanisms of benzobicyclon is important due to the unique rotation of rice and crayfish in Louisiana on the same fields. Benzobicyclon persistence into the crayfish growing seasons may lead to unintended consequences for crayfish growth and production, assuming there is toxicity to crawfish. …


Element Transport In A River-Lake Continuum Across Forest-Dominated Landscapes: A Case Study In Central Louisiana, Zhen Xu Mar 2020

Element Transport In A River-Lake Continuum Across Forest-Dominated Landscapes: A Case Study In Central Louisiana, Zhen Xu

LSU Doctoral Dissertations

Studying the biogeochemical connectivity between rivers and lakes can help us understand their ecological and environmental impacts within a drainage basin, which is especially true for forest watersheds that play a vital role in provisioning freshwater services to ecosystems and downstream communities. This dissertation research consists of three interconnected studies with the overarching goal of discerning the connectivity of elements in a river-lake continuum across forest-dominated landscapes. These studies utilized water samples and in situ measurements collected from the Little River-Catahoula Lake continuum in the subtropical Louisiana, USA at monthly intervals during 2015-2016 and 1978-2008 historical water quality, hydrological and …


Hydrodynamics And Sediment Dynamics In A Receiving Basin For Sediment Diversion: A Case Study In Barataria Bay, Louisiana, Usa, Guandong Li Mar 2020

Hydrodynamics And Sediment Dynamics In A Receiving Basin For Sediment Diversion: A Case Study In Barataria Bay, Louisiana, Usa, Guandong Li

LSU Master's Theses

Barataria Bay is a receiving basin of Mid-Barataria Sediment Diversion in Louisiana, USA. In this region the data of sediment transport and hydrodynamics are scarce but important for the design and planning of sediment diversion to be implemented in near future. Four-months bottom boundary layer observation was conducted to study winter and spring hydrodynamics and sediment dynamics in the bay. Hourly waves, tides, currents and bottom suspended sediment concentration were measured using multiple optical and acoustic sensors attached to two tripod platforms. High-temporal resolution data indicated that during winter, salinity at northern bay was mainly controlled by northerly wind during …


Antibiotic Resistance In Bacteria From Songbirds And Fitness Studies Following Environmental Stressors In Vitro, Leah R. Forsyth Mar 2020

Antibiotic Resistance In Bacteria From Songbirds And Fitness Studies Following Environmental Stressors In Vitro, Leah R. Forsyth

LSU Master's Theses

Since their initial discovery in 1928, antibiotics have been utilized for agriculture and human health purposes. The increasing use of antibiotics by humans and the rapid evolution of antibiotic resistance might be leading to the presence of more antibiotic-resistant bacteria in the environment. Understanding potential relationships between humans, bacteria, and the environment is important in order to study the spread and progression of antibiotic resistance in bacteria. Several past studies have focused on oxidative stress, temperature stress, and antibiotic resistance in bacteria, but to my knowledge few if any have done a wide comparison between these environmental stressors and the …


Conservation Potential And Mechanisms Of Avian Decline In Experimentally Fragmented And Regenerating Amazonian Rainforest, Cameron Lee Rutt Mar 2020

Conservation Potential And Mechanisms Of Avian Decline In Experimentally Fragmented And Regenerating Amazonian Rainforest, Cameron Lee Rutt

LSU Doctoral Dissertations

Twenty percent of the Brazilian Amazon has now been deforested, and deforestation rates are increasing. Yet the process of deforestation threatens biodiversity beyond the direct loss of habitat by inducing edge effects and creating forest fragments. In the tropics, among the most vulnerable birds to these human disturbances are a group of insectivorous species that forage on or near the ground. A variety of mechanisms have been proposed to explain these declines, but evidence for these hypotheses remains scare or equivocal. In this study, we examine three proposed mechanisms—physiological constraints to bright light, reduced breeding activity and nest success, and …


Mass Spectrometric Calibration For Real -Time Hydrocarbon Detection, Makuachukwu Mbaegbu Feb 2020

Mass Spectrometric Calibration For Real -Time Hydrocarbon Detection, Makuachukwu Mbaegbu

LSU Master's Theses

Determining gas compositions from live well fluids on a drilling rig is critical for real time formation evaluation. However, development and utilization of a reliable mass spectrometric method to accurately characterize these live well fluids is always a challenging issue because of lack of a robust, quick and effectively selective instrument and method. The primary goal of this research is to understand reasons of such discrepancies in results between “good” spectra, and “poor” ones. The objectives are thus to identify the detection issues, calibrate and QA/QC the instruments, and analyze the results in lab settings. In this study, we used …


Assessment Of Soil Protein And Refractory Soil Organic Matter Across Two Chronosequences Of Newly Developing Marshes In Coastal Louisiana, Usa, Stuart Alexander Mcclellan Feb 2020

Assessment Of Soil Protein And Refractory Soil Organic Matter Across Two Chronosequences Of Newly Developing Marshes In Coastal Louisiana, Usa, Stuart Alexander Mcclellan

LSU Doctoral Dissertations

The impacts of sea-level rise and hydrologic manipulation are threatening the stability of coastal marshes throughout the world, thereby increasing the potential for re-mineralization of soil organic matter (SOM) in these systems. Such threats have prompted marsh restoration efforts, particularly in coastal Louisiana, yet it is unclear how the slowly decomposing (refractory) and quickly decomposing (labile) fractions of SOM may be differentially affected by different approaches to marsh restoration. Additionally, otherwise labile compounds may accumulate in the soil via a range of protective mechanisms, including rapid burial and association with organic compounds that are thought to enhance soil aggregation, such …