Physical Sciences and Mathematics Commons^™

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 …

From The River To The Gulf: An Investigation Of Biogeochemical Cycling In Wetland Soils And Coastal Shelf Sediments, Katie Bowes

LSU Master's Theses

Louisiana is home to 40% of the coastal wetlands in the lower 48 states, yet accounts for 80% of the coastal wetland loss in this region. This loss is attributed to decreased sediment supply, levee alteration, sea level rise, channelization, and subsidence. The levee system in Louisiana disconnected coastal wetlands from the main stem of the Mississippi River (MSR), reducing the amount of land-building sediment that reaches coastal wetlands. This disconnection also allows a greater percentage of river discharge, including agricultural contaminants and runoff, to flow into the northern Gulf of Mexico (NGOM).

The 2012 Coastal Master Plan proposed eight …

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 …

Artificial Oyster Reefs In The Northern Gulf Of Mexico: Management, Material, And Faunal Effects, Jessica Nicole Furlong

LSU Master's Theses

Artificial oyster reefs seek to restore reef ecosystem services, such as water filtration, shoreline protection, and habitat for nekton. This study established three objectives to address the dispersed nature of artificial reef information in the Gulf of Mexico (GoM) and lack of post-construction monitoring assessments. First, to document the extent of activities in the GoM, we developed a database of all inshore artificial oyster reefs created for restoration purposes. Of the 422 reefs in the resultant database, a third or less provided records of entities involved (27%), restoration goals (24%), area (20%), monitoring efforts (15%), relief (9%), and costs (8%). …

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 …

Estimating The Population Of Greater And Lesser Scaup During Winter In Off-Shore Louisiana, Sean David Kinney

LSU Master's Theses

I analyzed data from an experimental aerial transect survey, using stratified random sampling, to estimate wintering populations of greater scaup (Aythya marila) and lesser scaup (Aythya affinis) (hereafter scaup) in off-shore waters along the coast of Louisiana during winters 2000-2002. My objectives were to evaluate anecdotal reports of large numbers of scaup in off-shore waters of Louisiana during winter, and to develop estimates and confidence intervals for numbers of scaup in this area. My analysis yielded estimates of 815,700, 420,600, and 791,000 scaup in off-shore Louisiana for years 2000-2002, respectively. Confidence intervals were 1,087,000 to 545,000, 594,300 to 247,000, and …