Physical Sciences and Mathematics Commons^™

Estimation Of Economic Risk From Coastal Natural Hazards In Louisiana, Rubayet Bin Mostafiz

LSU Doctoral Dissertations

Louisiana, U.S.A., is among the most vulnerable areas globally to coastal natural hazards, with risk vulnerability likely increasing. The risks associated with non-tropical-cyclone hazards in Louisiana’s coastal zone have been understudied. This research enhances present and future (i.e., 2050) Louisiana risk assessment using locally-weighted, model-based hazard frequency/intensity and population projections.

Results suggest that property risks associated with extreme cold temperature and tornado are and will remain costlier than those for hail and lightning. Property risks of extreme cold temperature and hail are projected to decrease with the expected warming temperatures, with those of all four of these hazards peaking in …

Wetland Soil Development Along Salinity And Hydrogeomorphic Gradients In Active And Inactive Deltaic Basins Of Coastal Louisiana, Amanda Fontenot

LSU Master's Theses

Coastal wetlands provide an abundance of ecosystem services that benefit society, such as essential habitat for commercial species, storm protection, nutrient cycling, and carbon storage. Louisiana faces rapid rates of relative sea level rise (natural subsidence and eustatic sea levels) that threaten wetland survival, which are amplified by a reduction of riverine sediment input. An important determining factor of marsh survival is the formation of wetland platform elevation, known as vertical accretion, which is determined by several processes including sediment deposition & erosion, below ground biomass (BGB) productivity, decomposition of organic matter, shallow & deep subsidence, and soil compaction. Feldspar …

Impact Of Oil And A Tropical Cyclone On An Omnivore And Herbivore Population In Salt Marshes Of Louisiana, Hannah K. Gordon

LSU Master's Theses

Terrestrial arthropods are the ideal ecological indicators for the health of a salt marsh. Salt marshes are under extreme continuous stressors including climate change, land loss, oil spills, and tropical cyclones. Such stressors impact trophic and species level interactions, food resources, dispersal and population size of insects. In the present study, we collected terrestrial arthropods from eleven sites around Barataria Bay, five sites were oiled and five sites were unoiled, to determine the impact of the redistribution of oil from the Deepwater Horizon oil spill. Site C6 was excluded from the oiled and unoiled data because it was in close …

Changes In Heat Metrics Following A Major Hurricane And Implications On Heat Stress, Cade Reesman

LSU Master's Theses

Tropical cyclones modify surface-atmosphere interactions in several ways, including the destruction of patches of tree canopy, increasing the direct and diffuse (shortwave) radiation reaching the surface. This addition of radiation at the surface impacts the sensible, latent, and substrate heat (energy) fluxes, generating heat anomalies along the hurricane’s track, which, among other effects, contributes to the higher post-hurricane surface air temperatures. This study consists of a case study on Hurricane Laura (2020) to examine hurricane defoliation impacts on heat stress metrics. Normalized difference vegetation index (NDVI) data from NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) identified the spatial extent of defoliation …

The Effect Of Pesticides And Ultraviolet Radiation On Coastal Invertebrates And The Need For More Research On Multiple Stressors And Predator-Prey Interactions, Chase Robinson

Honors Theses

No abstract provided.

A Numerical Investigation Of Flood And Sediment Dynamics Over The Coastal Watersheds During Hurricane Events, Dongxiao Yin

LSU Doctoral Dissertations

Landfalling tropical cyclones can cause catastrophic floods and sediment disturbance over the coastal watersheds. This study aims to unravel the contribution of different processes to hurricane-induced flooding, to assess the uncertainties in flood modelling and forecasting, and to advance the techniques in sediment simulation over coastal watersheds during hurricanes.

First, I examined the hydrometeorology and hydrology of Hurricane Florence (2018) induced inland flooding. My results suggest that the slow motion in combination with the “L-shaped” path was the most distinctive feature of the hurricane that incurred catastrophic and widespread rainfall and flooding over the Cape Fear River Basin (CFRB).

Second, …

Effects Of Meteorologic Events On Wave Climate And Current Regime In A Shallow, Microtidal Bay, Jay S. Merrill

LSU Master's Theses

Along coastal Louisiana and within the shallow microtidal Barataria Bay estuary, meteorological events can play a primary role in influencing wave climate and circulation patterns. Understanding the effects of hurricanes and smaller tropical storms on hydrodynamic processes is important for constraining and predicting hydrodynamic variation in Barataria Bay, which, largely due to impacts from wave energy, is currently experiencing rapid wetland loss and is a major focus of coastal restoration efforts. Two bottom-mounted upward-facing Acoustic Current Doppler Profilers and wave, temperature, and depth recorders were installed in the lower portions of Barataria Bay to measure the wave climate and three-dimensional …

Peak Chlorophyll A Concentrations In The Lower Mississippi River From 1997 To 2018, R. Eugene Turner, Charles S. Milan, Erick M. Swenson, James M. Lee

Faculty Publications

Large and turbid rivers have varying temperatures, light conditions, nutrient availability, and nutrient ratios that may affect phytoplankton communities and occur within a changing world of point and nonpoint source nutrient loadings. We investigated how these physical and chemical factors affect Chlorophyll a (Chl a) concentrations in the Mississippi River, the largest river in North America, by sampling 878 times from February 1997 to December 2018 near its terminus at Baton Rouge, Louisiana. We hypothesized that nutrient concentrations and ratios were significant factors limiting phytoplankton biomass accumulations in this turbid river. The Chl a concentrations were in the "poor" water …

Connecting The Dots: Transmission Of Stony Coral Tissue Loss Disease From The Marquesas To The Dry Tortugas, Thomas Dobbelaere, Daniel M. Holstein, Erinn M. Muller, Lewis J. Gramer, Lucas Mceachron, Sara D. Williams, Emmanuel Hanert

Faculty Publications

For the last 7 years, Florida's Coral Reef (FCR) has suffered from widespread and severe coral loss caused by stony coral tissue loss disease (SCTLD). First observed off the coast of Miami-Dade county in 2014, the outbreak has since spread throughout the entirety of FCR and some areas of the Caribbean. However, the propagation of the disease through FCR seemed to slow down when it reached the western end of the Marquesas in August 2020. Despite being present about 30 km (similar to 20 miles) from the Dry Tortugas (DRTO), SCTLD was not reported in this area before May 2021. …

Testing Xrf Identification Of Marine Washover Sediment Beds In A Coastal Lake In Southeastern Texas, Usa, Harry F. L. Williams, Chelsea E. Beaubouef, Kam-Biu Liu, Nicholas Culligan, Lance Riedlinger

Faculty Publications

This study tests the ability of a novel approach to identifying washover beds in coastal lakes. Combined X-Ray Fluorescence (XRF) and cluster analysis was used to identify hurricane washover beds in sediment cores from Clam Lake on the McFaddin National Wildlife Refuge in southeastern Texas. The lake is known to contain washover beds from recent hurricanes, but the washover sediment has similar microfossil, loss-on-ignition and textural characteristics to non-washover sediment and is not readily distinguishable. Sediment cores taken from marshes surrounding the lake do contain visually-recognizable sandy washover beds of Hurricanes Ike, Rita, Carla and Audrey. XRF analysis of these …