Digital Commons Network^™

Breaking Coastal Hypoxia: Destratification Of Gulf Of Mexico Deadzone To Encourage Oxygen Transport Downwards To Maintain Marine Fauna, Veda Thipparthi

LSU Master's Theses

As a consequence of seasonal eutrophication and human input, a vast hypoxic area termed The Dead Zone develops every year in the Gulf of Mexico (GOM) during summer along the Louisiana coastline characterized by vertical seawater density-stratification with oxygen concentrations less than 2 mg.l^-1 at the seafloor. It poses a threat to bottom-dwelling faunae and their environment which has negative ecological and economic consequences. This project aims to mitigate hypoxia by employing mechanical impellers placed at strategic water depths and locations in the Gulf. Enhanced transport of oxygen results by mixing oxygen-enriched seawater at the surface, downward into the …

The Use Of Social Media In Emergency Management By Public Agencies And Non-Governmental Organizations: Lessons Learned From Areas Affected By Hurricanes Isaac, Sandy, And Harvey, Ryan Hamilton Kirby

LSU Doctoral Dissertations

Natural disasters are increasingly costly for the United States. The literature suggests emergency managers may improve disaster outcomes and enhance disaster resilience by supplementing their official public-communications methods with more bi-directional communication tactics using social media. This study aims to understand how social media is used within the “whole community” of emergency management in areas affected by recent hurricanes. The first research objective examines how social media is used by governmental and non-governmental organizations across the four phases of emergency management (preparedness, response, recovery, mitigation). The second objective is to identify challenges governmental and non-governmental groups have encountered and strategies …

The Power Of Wording: An Evaluation Of Framing Effects, Chelsea Romph

Honors Theses

No abstract provided.

The Wood Pellet Industry In The United States South: An Exploratory Study Of Resident Environmental, Social, And Economic Perceptions, Mason Thomas Leblanc

LSU Master's Theses

This thesis research provides insight into the wood pellet manufacturing industry from the perspectives of residents in the US South, focusing on environmental, social, and economic constructs. The region is the largest producer and exporter of wood pellets in the world. The focus of previous research on wood pellets has focused on environmental, energy, and economic attributes. This study is the first of its kind to expand the research to investigate in-depth socio-economic dynamics and fill a general gap in knowledge of the relationship between the wood pellet industry and public supply-side issues in the region. Two rounds of a …

Development Of A Tunable Platform For The Study Of Geomacromolecular Matrices Using Controlled Radical Polymerization, Arjun Pandey

LSU Doctoral Dissertations

Soil is an important environmental component, and the study of soil processes have many practical implications such as improvement in agriculture, mitigation of climate change etc. The widespread use of Agricultural Chemicals (ACs) in modern agriculture has resulted in adverse effects in environment and human health mostly through contamination into food and water sources. Study of fate, bioavailability, and transport of ACs involves molecular level understanding of their interactions with soil. This can be challenging due to complex and heterogeneous nature of soil. One common approach used is the correlation of macroscopic properties of soil, (e.g. sorption) with empirical parameters …

Visualization And Quantitation Of Radioiodine Distribution In Silver Zeolite Cartridges, Daniel Dimarco

LSU Master's Theses

Iodine 131 is a major fission product released during a nuclear incident. This isotope provides a serious health hazard for humans and the environment, therefore nuclear power plants must monitor releases using air sampling. The air sampling is accomplished using air filter cartridges using silver zeolite as a filter media. During an emergency situation, silver zeolite is useful for its affinity to I-131 without adsorbing other radioactive gases. After leaving the plume, these cartridges are counted in a low background area. This measurement does not take into account the distribution of radioiodine in the cartridge. This study explores two methods …

Reproductive Parameters And Female Breeding Season Survival Of Rio Grande Wild Turkeys In South Central Texas, Jacob White

LSU Master's Theses

Historically, Rio Grande wild turkeys in south central Texas have been at lower densities than other portions of the state. Within the Oak-Prairie Wildlife District of Texas, Rio Grande wild turkey regulatory restrictions are different for counties in the eastern and western portions of the ecoregion. Due to perceived increases in turkey density in the eastern portion of the ecoregion (hereafter 1-bird zone), Texas Parks and Wildlife Department (TPWD) considered increasing the bag limit to match counties in the western portion of the district (hereafter 4-bird zone) in order to increase hunting opportunities. However, if regulatory changes are to be …

Visualizing The Fate And Distribution Of Pahs In Spartina And Avicennia Tissues From Barataria Basin, La, Kristina Jeannette Sebastian

LSU Master's Theses

During crude oil spill events, vegetation in marsh environments sequester polycyclic aromatic hydrocarbons (PAHs) from the crude oil by partitioning from the air phase through the waxy cuticle on the leaf surface. Recent studies from Macondo oil-impacted marshes have demonstrated that cycling of low molecular weight petrogenic PAHs occurs through the cuticle and other leaf tissue. At present, our understanding of how PAHs travel through the cuticle is coarse and limited by grab samples across the entire leaf, which preventing a full understanding the dynamics of PAH cycling in this environment. Multiphoton (MP) confocal microscopy visualizes the distribution of PAHs …

The Importance Of Landscape Position Information And Elevation Uncertainty For Barrier Island Habitat Mapping And Modeling, Nicholas Matthew Enwright

LSU Doctoral Dissertations

Barrier islands provide important ecosystem services, including storm protection and erosion control to the mainland, habitat for fish and wildlife, and tourism. As a result, natural resource managers are concerned with monitoring changes to these islands and modeling future states of these environments. Landscape position, such as elevation and distance from shore, influences habitat coverage on barrier islands by regulating exposure to abiotic factors, including waves, tides, and salt spray. Geographers commonly use aerial topographic lidar data for extracting landscape position information. However, researchers rarely consider lidar elevation uncertainty when using automated processes for extracting elevation-dependent habitats from lidar data. …

Sources And Chemical Stability Of Soil Organic Carbon Along A Salinity Gradient And A Chronosequence Of Created Brackish Marshes In Coastal Louisiana, Megan L. Kelsall

LSU Master's Theses

Tidal marshes have been recognized for providing a number of important ecological services including soil carbon sequestration. However, the loss of tidal marsh habitat due to climate change and anthropogenic stressors exposes previously stored soil organic carbon (SOC) to oxidation. The vulnerability of SOC to oxidation depends on its chemical stability and environmental conditions limiting decomposition. Labile organic carbon (LC), decomposes quickly unless abiotic conditions limit decomposition. Recalcitrant organic carbon (RC) decomposes slower and is stored for longer time periods. Predicting long-term storage of SOC is complicated by the potential for multiple SOC sources, differences in chemical stability, and variation …

Assessment Of Excess Thyroid Cancer Risk Following A Hypothetical Radiological Incident In Louisiana And Best-Case Risk Reduction Achieved By Thyroid Blockade, Garrett A. Otis

LSU Master's Theses

Radioactive isotopes of iodine are produced by nuclear power plants as a byproduct of nuclear fission reactions. If these isotopes are released into the environment, such as during a breach of containment, they constitute a health risk to exposed individuals. To mitigate the risk of thyroid cancer due to exposure to radioactive iodine, “iodide prophylaxis,” also known as “thyroid blockade,” can be used, usually by administration of potassium iodide (KI). In some areas of the world, KI has been provided to the general public by their governments as a precautionary measure against potential nuclear power plant incidents. However, in the …

Cogongrass (Imperata Cylindrica (L.) Beauv.) In Louisiana: Cause And Consequence, Lorissa A. Radunzel-Davis

LSU Master's Theses

Cogongrass (Imperata cylindrica (L.) Beauv.), an invasive species from East Asia, is found worldwide and is problematic in several countries. In the United States, it grows primarily in the Southeast, reducing biodiversity by growing in dense patches and potentially causing mortality and reducing value of native and planted pinelands due to a high burning temperature. Using Lee Memorial Forest, a Louisiana State University AgCenter property in Washington Parish as a study site, this thesis explores cogongrass in Louisiana with emphasis on soil microbes and soil legacy effects on native plant species. Cogongrass populations at Lee Memorial Forest were more …

Decadal Changes Of Soil Physiochemical Properties In A Freshwater Wetland After Hydrologic Reconnection, Alina Spera

LSU Master's Theses

Sediment, nutrient deprivation and salt water intrusion, among other factors, are driving widespread organic soil collapse and marsh loss in the Mississippi River Delta. Freshwater diversions were designed to reintroduce Mississippi River water and dissolved nutrients into the adjacent basins to manage salinity and slow land loss by maintaining marsh vegetation and nutrient cycling functions. These diversions are controversial by a few, suggesting that nutrient enrichment without a sediment subsidy can lead to further wetland loss in the receiving basins. In this study, a soil characterization is presented for the receiving marsh of the Davis Pond diversion in 2007, just …

Matrix Recharge In A Shrink-Swell Floodplain Forest Soil, Savannah R. Morales

LSU Master's Theses

Despite the global distribution of fine-grained Vertisols, the hydrology of these floodplain soils is still not well understood. Vertisols shrink and swell depending on soil moisture leading to a range of soil pore sizes, from large macropore cracks to smaller micropores, and consequently a range of hydraulic conductivities. Despite the plethora of research indicating the importance of both flooding and soil moisture in floodplain ecosystems, the specific role that flooding plays in soil moisture recharge has been less widely studied and remains of interest. Blue food dye and deuterated water were used as tracers to determine the role of the …

Reproductive Parameters And Methodologies For The Culture Of Golden Topminnows (Fundulus Chrysotus) And Bluenose Shiners (Pteronotropis Welaka), Jacob A. Fetterman

LSU Master's Theses

The global ornamental fish trade has expanded over the past 20 years, requiring captive rearing methods to be improved or developed for species of interest. Aquaculture of desirable species is preferable over wild harvest to conserve natural habitats and biodiversity. This thesis focused on improving culture methods for Golden Topminnows Fundulus chrysotus and developing culture methods for Bluenose Shiners Pteronotropis welaka, both native fishes of the southeastern United States with ornamental demand. A combination of reproductive metric analyses, examination of historical collections, and captive spawning trials were employed to target specific objectives for each species. In female Golden Topminnows, …

Building A Better Batture: A Regional Recreational Enhancement Around The Morganza To The Gulf Levee, Taylor N. Fehmel

LSU Master's Theses

Twenty-five years ago, the existing flood protection levees along the Louisiana coastline were removed and construction was started by Terrebonne Levee and Conservation District on a new project called ‘Morganza to the Gulf’ or MTG. This project was undertaken to construct a new flood protection levee system around Louisiana in the communities in Terrebonne and Lafourche Parish. The MTG Levee is one of the first coastal projects in Louisiana to incorporate a risk-based analysis for a double levee system containing both local parish drainage levees and future storm surge levees of MTG. It was designed to protect approximately 250,000 people …

Effects Of Oil And Gas Development On Waterfowl Nesting Ecology In The Bakken Formation Of North Dakota, Cassandra G. Skaggs

LSU Master's Theses

The Prairie Pothole Region (PPR) is one of the most important areas on the continent for grassland-nesting birds. Thirty percent of the PPR overlaps the Bakken shale formation where rapidly accelerating oil and gas development has the potential to impact millions of breeding waterfowl. While oil and gas development has negatively affected other ground-nesting birds such as sagebrush passerines and Greater Sage-Grouse (Centrocercus urophasianus) in Wyoming, the potential impact on breeding waterfowl in the PPR is unknown. In addition, the PPR landscape is already heavily fragmented by agriculture, and increasing land conversion and disturbance from petroleum extraction may further …

Assessment And Correction Of Lidar-Derived Dems In The Coastal Marshes Of Louisiana, William M. Lauve

LSU Master's Theses

The onset of airborne light detection and ranging (lidar) has resulted in expansive, precise digital elevation models (DEMs). DEMs are essential for modeling complex systems, such as the coastal land margin of Louisiana. They are used for many applications (e.g. tide, storm surge, and ecological modeling) and by diverse groups (e.g. state and federal agencies, NGOs, and academia). However, in a marsh environment, it is difficult for airborne lidar to produce accurate bare-earth measurements and even accurate elevations are rarely verified by ground truth data. The accuracy of lidar in marshes is limited by the sensor’s resolution …

Environmental Controls On Dissolved Carbon Export And River Geochemistry - A Case Study In The Mississippi-Atchafalaya System, Jeremy Reiman

LSU Master's Theses

Rivers serve as an important medium for the exchange of elements between land, ocean, and atmosphere. This thesis consists of three interconnected studies with the overarching goal of analyzing the environmental factors influencing dissolved carbon dynamics and river geochemistry in large rivers. These studies utilized river water samples and in-stream measurements collected from the Mississippi and Atchafalaya Rivers at hourly to monthly intervals between 2013 to 2018, along with ambient river and meteorological data downloaded from public-access databases. Results indicate substantially higher dissolved organic carbon concentrations (DOC, 611 ±181 µmol L^-1) but lower concentrations of dissolved inorganic carbon …

Vulnerability Of Industrial Facilities In The Lower Mississippi River Industrial Corridor To Relative Sea Level Rise And Tropical Cyclone Storm Surge, Joseph Blake Harris

LSU Doctoral Dissertations

Relative sea level rise (RSLR) and tropical cyclone-induced storm surge are major threats to the Lower Mississippi River Industrial Corridor (LMRIC) which has approximately 120 industrial complexes located within the corridor. Spatial interpolation methods were applied to the 2004 National Oceanic and Atmospheric published Technical Report #50 subsidence dataset and cross-validation techniques were used to determine the accuracy of each method. Digital elevation models (DEMs) were created for the years 2025, 2050, and 2075, based on these predictive surface of subsidence rates. Future DEMs were utilized to model RSLR and determine the extent of storm surge on the LMRIC by …

Fate Of Selected Pollutants Of Concern On Particulate Matter (Pm) Surface, Ajit Ghimire

LSU Doctoral Dissertations

This research focuses on the environmental fate of particle associated pollutants such as Polybrominated Diphenyl Ethers (PBDEs), Polyaromatic Hydrocarbons (PAHs), and Environmentally Persistent Free Radicals (EPFRs) with a special emphasis on their transformation due to interaction with a matrix or co-pollutants. It encompasses two approaches to the stated problems: analysis of samples collected in the environment and laboratory simulation of the molecular transformations.

The PBDE studies relied on the ambient air Particulate Matter (PM) samples collected from Bangkok, Thailand. Results showed the presence of various PBDE homologs from tri- to hepta-PBDEs on both PM_2.5and Total Suspended Particle (TSP) …

Deltaic Wetland Dynamics From Seasonal To Centennial Scales, Giancarlo A. Restreppo

LSU Doctoral Dissertations

The lower plain of the Mississippi River Delta contains approximately five coastal sedimentary basins that are topographically defined, and one shelf-crossing depocenter (the Birds Foot Delta). These depositional systems receive varying quantities of sediment from fluvial and marine sources and have rates of coastal land loss that are roughly inversely proportional to fluvial sediment supply. To combat land loss along these regions, Louisiana has launched a historic campaign to sustain and regrow coastal lands using, in part, river sediment diversions. Fine sediments constitute the majority of sediment load in the Mississippi River, but are under-studied with respect to dispersal processes, …

Determination Of Conversion Factors For Various Calibration Geometries Using Barium-133 In A Silver Zeolite Cartridge, Amin Hamideh

LSU Master's Theses

Iodine-131 (I-131) is a major fission product among other radionuclides released during a nuclear incident. This radioiodine has a half-life of 8.02 days and the primary organ of uptake through ingestion or inhalation is the thyroid gland. For these reasons, nuclear power plants must routinely monitor I-131 through air sampling. Currently, there are two adsorbing media to collect I-131: activated charcoal and silver zeolite cartridges. Silver zeolite cartridges are generally used during a post nuclear incident due to its affinity for iodine while not adsorbing noble gases such as krypton-85 and xenon-135. After an air sample is taken from a …

The Effect Of Invasive Aquatic Vegetation On Odonate Diversity In An Urban Area, Sarah Thomas

Honors Theses

No abstract provided.

Assessing Knowledge Of Coastal Land Loss In Louisiana High School Graduates, Madelyn Smith

Honors Theses

No abstract provided.

Voc Emission Factors From 3d Printers - Abs (Acrylonitrile-Butadiene-Styrene) Type Filaments, Dean Lay

LSU Master's Theses

Acrylonitrile-butadiene-styrene (ABS) is a polymer that is widely used in many plastic products and is receiving new attention due to its use as a filament for fused deposition modelling (FDM) 3D printers. It has been shown to emit potentially dangerous volatile organic compounds (VOCs) when heated at temperatures used in the 3D printing process. Many new products are becoming available that contain various additives to the polymer matrix, which have an unknown effect on the emission profiles and rates. In this study a method is developed using a modified system for thermal diagnostic studies (STDS) to evaluate VOC emission from …

Evaluation Of Naturally Occurring Radioactive Material In Seafood From The Gulf Of Mexico, Charles Algeo Wilson Iv

LSU Doctoral Dissertations

Radioactive disintegration of naturally occurring radioactive material was modeled with high precision and no assumptions to better understand serial decay in high order disequibrlia. This model helped develop a new method of quick analysis of NORM, where radioactivity can be measured with reasonable certainty before secular equilibrium is established. This approach was a significant improvement on previous similar approaches, halving time required for the same results and reduced wait time compared to classical approaches by 92%. Consequentially, NORM was measured in selected seafood samples from three areas in the Gulf of Mexico. Red Snapper, Red Drum, Northern Whiting, Spotted Trout …

Monitoring Sediment Dynamics And Vegetation Competition Based On Micro-Topography And Terrestrial Lidar For Wetland Restoration, Xukai Zhang

LSU Doctoral Dissertations

With the ability to attenuate wave and limit erosion, coastal wetlands are important to protect shoreline for coastal communities. Micro-topography in coastal wetlands has a significant influence on hydrology, habitat variability and ecosystem functions. However, when mapping micro-topography by terrestrial LiDAR in coastal environments, the coverage of dense vegetation leads to a relatively low chance of laser penetration through the canopy to the ground. This dissertation proposes a rapid and flexible terrain mapping solution for the densely vegetated coastal environment by integrating crown structure from terrestrial LiDAR with terrain samples from GPS. The validated results in the study site demonstrate …

An Airlifted Tidal Mesocosm For Oil Degradation Studies, Daniel Christopher Alt

LSU Doctoral Dissertations

Mesocosms were constructed to allow scientists to isolate variables in a microtidal marsh environment, mimicking the natural conditions found in Terrebonne Bay. The control offered by these mesocosms is given by a process control system that takes user inputs and automates water movement. Twelve mesocosms were constructed, each holding 4.02 m³ (142 ft³) of marsh soil and 3.88 m³ (137 ft³) of water to give 3 experimental levels and a control, all in triplicate.

Each mesocosms that was constructed contained marsh plants in soil plugs 9 feet in diameter and 3 feet deep. These …