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Full-Text Articles in Physical Sciences and Mathematics

Effects Of Oil-Contaminated Sediments On Submerged Vegetation: An Experimental Assessment Of Ruppia Maritima, Charles W. Martin, Lauris O. Hollis, R. Eugene Turner Oct 2015

Effects Of Oil-Contaminated Sediments On Submerged Vegetation: An Experimental Assessment Of Ruppia Maritima, Charles W. Martin, Lauris O. Hollis, R. Eugene Turner

Faculty Publications

Oil spills threaten the productivity of ecosystems through the degradation of coastal flora and the ecosystem services these plants provide. While lab and field investigations have quantified the response of numerous species of emergent vegetation to oil, the effects on submerged vegetation remain uncertain. Here, we discuss the implications of oil exposure for Ruppia maritima, one of the most common species of submerged vegetation found in the region affected by the recent Deepwater Horizon oil spill. We grew R. maritima in a range of manipulated sediment oil concentrations: 0, 0.26, 0.53, and 1.05 mL oil /L tank volume, and tracked …


Assessing The Impacts Of Nutrient Load Reduction Scenarios On The Extent And Severity Of Hypoxia In The Northern Gulf Of Mexico, David Fertitta Apr 2015

Assessing The Impacts Of Nutrient Load Reduction Scenarios On The Extent And Severity Of Hypoxia In The Northern Gulf Of Mexico, David Fertitta

Honors Theses

No abstract provided.


Anthropogenic Impacts On Soil Microbial Processes In Coastal Wetlands: Nutrient Loading And Rising Co2 Levels, Havalend Ellen Steinmuller Jan 2015

Anthropogenic Impacts On Soil Microbial Processes In Coastal Wetlands: Nutrient Loading And Rising Co2 Levels, Havalend Ellen Steinmuller

LSU Master's Theses

Atmospheric carbon dioxide (CO2) levels and global eutrophication are anthropogenic stressors impacting the environment of specific interest in wetland systems. Wetlands occupy a critical interface between terrestrial and aquatic environments. Fertilizer use for agriculture and treated wastewater disposal has increased nutrient loading to wetlands. Conflicting results on impacts of nitrogen loading to coastal wetland soils have been reported, though most studies have investigated short-term impacts of nutrient loading, not long-term integrated impacts. I investigated an 11-year period of nutrient loading on soils in an oligohaline coastal wetland. Nitrogen treatments of 0, 50, 200, and 1200 kg ha-1 yr-1 were paired …


Otoliths Then And Now: A Study Of Ancient And Modern Fish Populations In Louisiana's Coastal Waters, Marshall James Kormanec Jan 2015

Otoliths Then And Now: A Study Of Ancient And Modern Fish Populations In Louisiana's Coastal Waters, Marshall James Kormanec

LSU Master's Theses

Fish otoliths are composed of inorganic calcium carbonate that aid in gravity and auditory reception. Substances permanently accrete to otolith surfaces in distinct temporal patterns of alternating opaque and translucent rings; these rings are direct proxies for a fish’s age. The objective of my research is to demonstrate how otoliths can be used through time and space to estimate both age and growth of fish. I investigated the spatial differences in age distributions and growth models for red snapper, Lutjanus campechanus, at four natural shelf-edge reefs in the northwestern Gulf of Mexico. Red snapper cohorts ranged 1987-2010 cohorts, with the …


Fish Biomass And Community Structure Around Standing And Toppled Oil And Gas Platforms In The Northern Gulf Of Mexico Using Hydroacoustic And Video Surveys, Emily Marissa Reynolds Jan 2015

Fish Biomass And Community Structure Around Standing And Toppled Oil And Gas Platforms In The Northern Gulf Of Mexico Using Hydroacoustic And Video Surveys, Emily Marissa Reynolds

LSU Master's Theses

There has been relatively little study of the efficacy of decommissioned oil and gas platforms as artificial reef habitats for fish assemblages in the northern Gulf of Mexico (GOM). A variety of fish species have been reported on these structures, but the species biomass distribution and community structure has not been studied thoroughly. Hydroacoustic and video surveys were conducted quarterly from June 2013 to June 2014 at three standing and two toppled oil and gas platforms located approximately 130 km off the coast of Louisiana at 90 m depth; to gain information about the spatial biomass distribution and community structure …


Habitat Preferences Of Adult Spotted Seatrout, Cynoscion Nebulosus, In Lake Pontchartrain, Louisiana, Noelle Marie Bramer Jan 2015

Habitat Preferences Of Adult Spotted Seatrout, Cynoscion Nebulosus, In Lake Pontchartrain, Louisiana, Noelle Marie Bramer

LSU Master's Theses

Spotted seatrout (Cynoscion nebulosus) are a highly sought after sportfish, making up over 90% of the recreational fishery in Louisiana. As a significant portion of every life history stage is spent within its natal estuary, it is an ideal bio-indicator of estuarine health. As one of the largest estuaries in Louisiana, Lake Pontchartrain represents one such supporting ecosystem. From November 2012 to April 2014 acoustic tagging of individual fish, a lake-wide receiver array, and ArcGIS mapping software were utilized to determine the spatial distribution of spotted seatrout within the lake. Receivers were placed in representative locations including man-made and natural …


Effects Of Oil Spill And Recovery Of Terrestrial Arthropods In Louisiana Saltmarsh Ecosystem, Wokil Bam Jan 2015

Effects Of Oil Spill And Recovery Of Terrestrial Arthropods In Louisiana Saltmarsh Ecosystem, Wokil Bam

LSU Master's Theses

Saltmarshes are under continuous multiple stressors such as, land loss, erosion, climate change, environmental pollutions and oil spills, which affect the ecological communities inhabiting saltmarshes. Terrestrial arthropods play an important role in the ecology of saltmarshes, affecting primary production and decomposition. Arthropods are often found in the gut contents of Seaside Sparrows and fishes making them an important trophic link to terrestrial and marine vertebrates. Insects and spiders have the potential to be a good indicator of overall marsh health and environment as they are differentially sensitive to oil exposure. Oil pollutants may have significant long-term negative impacts on the …


Oil And Gas Platforms On Ship Shoal, Northern Gulf Of Mexico As Habitat For Reef-Associated Organisms, David Bradley Reeves Jan 2015

Oil And Gas Platforms On Ship Shoal, Northern Gulf Of Mexico As Habitat For Reef-Associated Organisms, David Bradley Reeves

LSU Master's Theses

Nearshore Louisiana has experienced substantial changes within the last half-century, including the annual formation of the world’s second largest hypoxic zone and the construction of thousands of oil and gas platforms (rigs). Ship Shoal and its rigs may provide important substrate in nearshore Louisiana because rigs act as de facto artificial reefs and the shoal’s bottom waters were well oxygenated on 43% of days when surrounding areas were hypoxic. From July to September of 2014, fish assemblages and hydrography were compared at shoal rigs, rigs inshore of the shoal, and rigs offshore of the shoal, and stone crab populations were …


Holecene Paleoenvironmental Reconstruction From The Shark River Estuary, Everglades, Florida, Qiang Yao Jan 2015

Holecene Paleoenvironmental Reconstruction From The Shark River Estuary, Everglades, Florida, Qiang Yao

LSU Doctoral Dissertations

This dissertation examines the paleoecological records from the Shark River Estuary in the southwestern part of the Everglades National Park (ENP), Florida, with primary goal of reconstructing the Holocene history of the coastal mangrove ecosystem in the Florida Coastal Everglades. Roughly 15 meters of sediments were collected from 4 study sites and subjected to loss-on ignition, palynological, and X-ray fluorescence analyses. According to the literature, the earliest communities of Rhizophora mangle (red mangrove) occurred prior to 8,000 cal yr BP in the south-central area of the Belize Barrier Reef Platform. Between 7,000 and 5,000 cal yr BP, Rhizophora was established …


Fish Assemblage Structure, Distribution, And Trophic Ecology At Northwestern Gulf Of Mexico Banks, Todd Langland Jan 2015

Fish Assemblage Structure, Distribution, And Trophic Ecology At Northwestern Gulf Of Mexico Banks, Todd Langland

LSU Doctoral Dissertations

The northwest Gulf of Mexico (Gulf) shelf-edge banks both provide unique hard bottom habitat and support the northernmost coral reefs on the North American continental shelf in a region that is generally characterized by low relief, soft sediments. The habitat value of many of these banks has led to their designation as Habitat Areas of Particular Concern (HAPC) and the Flower Garden Banks National Marine Sanctuary (FGBNMS). However, little is known about the fisheries resources and dynamics of the banks outside the FGBNMS. This study had three main objectives: 1) define reef fish assemblages at northwestern Gulf shelf-edge banks and …


Polycyclic Aromatic Hydrocarbons Dynamics In The Northern Gulf Of Mexico, Puspa Lal Adhikari Jan 2015

Polycyclic Aromatic Hydrocarbons Dynamics In The Northern Gulf Of Mexico, Puspa Lal Adhikari

LSU Doctoral Dissertations

Polycyclic aromatic hydrocarbons (PAHs) are introduced into the marine environment via oil seeps/spills, riverine discharges, continental runoff, coastal erosion, and atmospheric deposition. An estimated 2.1 x 1010g of PAHs entered into the northern Gulf of Mexico (GOM) during the Deepwater Horizon (DWH) oil spill in 2010. It became evident following the oil spill that accurate quantification of ultimate fate of these potentially carcinogenic and/or mutagenic organic pollutants is extremely challenging. In general, very little is known about PAHs fate, distribution and accumulation in the open ocean ecosystems. This study determines the upper ocean vertical fluxes and sedimentary PAHs accumulation rates …


Numerical Simulation Of Cold Front-Related Hydrodynamics Of Wax Lake Delta, Qian Zhang Jan 2015

Numerical Simulation Of Cold Front-Related Hydrodynamics Of Wax Lake Delta, Qian Zhang

LSU Doctoral Dissertations

This study applies a three-dimensional numerical model ECOM-si to simulate the circulation in the Wax Lake delta under winter cold front conditions. This model uses real topography and bathymetry of the area to reproduce tides and the circulation between December 2012 and January 2013, which captures a total of seven cold front passages. The model results demonstrate that the circulation in the Wax Lake delta area is significantly affected by the winter cold fronts. The major findings are: (1) Water fluxes in the delta distributary network are not solely propagated within the channels but also between the channels, indicating inundation …