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LSU Master's Theses

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Articles 151 - 168 of 168

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Feeding Ecology And Morphometric Analysis Of Paddlefish, Polyodon Spathula, In The Mermentau River, Louisiana, Nicole Adele Smith Jan 2004

Feeding Ecology And Morphometric Analysis Of Paddlefish, Polyodon Spathula, In The Mermentau River, Louisiana, Nicole Adele Smith

LSU Master's Theses

Little is known about the morphometrics and the feeding ecology of paddlefish in Louisiana. I examined the morphometrics and feeding ecology of paddlefish from the Mermentau River, Louisiana from March 2002 to February 2003. Paddlefish were examined morphometrically by taking measurements of eye-fork length (EFL), body cavity length (BCL), girth (G), vent girth (VG), mouth vertical (MTB), mouth horizontal (MSS), and mouth gullet bottom (MGB) to determine which parameters would give a better estimate of weight (W). Regression analysis resulted in a morphometric model of the form: logW = 10.10 + 1.52 (logEFL) + 1.21 (logG) + 0.24 (logVG) (r2 …

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Transport And Deposition Of Fluid Mud Event Layers Along The Western Louisiana Inner Shelf, Kristina Anne Rotondo Jan 2004

Transport And Deposition Of Fluid Mud Event Layers Along The Western Louisiana Inner Shelf, Kristina Anne Rotondo

LSU Master's Theses

The western Louisiana inner shelf along the Chenier Plain coast has experienced fluid mud deposition in response to increased fine sediment supplied by the Atchafalaya River since ~1950’s. The goal of this project is to assess the characteristics comprising the sedimentary strata and stratigraphic architecture that result from mud deposition on the inner shelf. Recent time-series cores collected from the inner shelf along the Chenier plain coast show the region is subject to transient fluid mud deposition, leading to high long-term accumulation rates. Sediment cores were collected in May 2001, March and May 2002 from the inner shelf landward of …

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The Fidelity Of Red Snapper (Lutjanus Campechanus) To Petroleum Platforms And Artificial Reefs In The Northern Gulf Of Mexico, Megan Blythe Peabody Jan 2004

The Fidelity Of Red Snapper (Lutjanus Campechanus) To Petroleum Platforms And Artificial Reefs In The Northern Gulf Of Mexico, Megan Blythe Peabody

LSU Master's Theses

The habitat value of petroleum platforms for red snapper, Lutjanus campechanus, is poorly understood. However, it is widely recognized by both scientists and fishermen that the presence of platforms in the northern Gulf of Mexico (GOM) has affected the distribution of red snapper by the addition of hard substrate habitat. I evaluated the habitat value of standing and toppled platforms by monitoring the fidelity of red snapper to these structures with acoustic telemetry. In May 2003, 125 red snapper were captured with hook and line at several platforms in a 35-km2 portion of the South Timbalier oil and gas lease …

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The Effects Of Nutrient Enrichment On The Decomposition Of Belowground Organic Matter In A Sagittaria Lancifolia - Dominated Oligohaline Marsh, Kristen Raye Laursen Jan 2004

The Effects Of Nutrient Enrichment On The Decomposition Of Belowground Organic Matter In A Sagittaria Lancifolia - Dominated Oligohaline Marsh, Kristen Raye Laursen

LSU Master's Theses

Wetlands improve water quality through sedimentation and the uptake of excess nutrients. As human population increases in the coastal zone, wetlands receive greater nutrient inputs. These additional nutrients may accelerate microbial activity, leading to faster decomposition rates. This decomposition could exceed belowground organic matter production, resulting in a net reduction in soil organic matter accumulation and vertical marsh accretion. The effects of nutrient enrichment on belowground organic matter decomposition in subtropical marshes have received little attention. As such, this research examined the effects of four levels of nitrogen combined with two levels of phosphorus enrichment on belowground decomposition through the …

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Freshwater And Nutrient Inputs To A Mississippi River Deltaic Estuary With River Re-Introduction, Emily Christina Grace Hyfield Jan 2004

Freshwater And Nutrient Inputs To A Mississippi River Deltaic Estuary With River Re-Introduction, Emily Christina Grace Hyfield

LSU Master's Theses

In this study, I quantified freshwater and nutrient inputs in the Breton Sound estuary which is receiving freshwater reintroduction in an effort to restore deteriorating wetlands. Almost all wetlands of the Mississippi deltaic plain are isolated from riverine input due to flood control levees along the Mississippi River. This has altered water and nutrient budgets and is a primary cause of the massive wetland loss in the delta. Maintenance of the delta depends on a healthy, functioning ecosystem which includes riverine input. The Breton Sound estuary is located southeast of New Orleans and until recently was hydrologically isolated from direct …

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Short-Term Evolution Of A Marsh Island System And The Importance Of Cold Front Forcing, Terrebonne Bay, Louisiana, Dana Ann Watzke Jan 2004

Short-Term Evolution Of A Marsh Island System And The Importance Of Cold Front Forcing, Terrebonne Bay, Louisiana, Dana Ann Watzke

LSU Master's Theses

Short-term, wave induced erosion along bay beaches in the northern Gulf of Mexico has been linked to the postfrontal phase of cold front passages. Not until recently has consideration been given to the importance of wave erosion on marshes fringing large bays during the entire cold front event. Two WAVCIS (Wave-Current-Surge-Information System) stations were established on the north and south flank of a small marsh island in Terrebonne Bay, Louisiana, to measure and elucidate the hydrodynamic response to these events. Data from WAVCIS stations, which includes wind speed and direction, air temperature, significant wave height and water level, were collected …

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Stormwater Diversion As A Potential Coastal Wetland Restoration Method, Jennifer Howard Woods Jan 2004

Stormwater Diversion As A Potential Coastal Wetland Restoration Method, Jennifer Howard Woods

LSU Master's Theses

The Barataria-Terrebonne estuary has been eroding at a rate of up to 103.6 km2 yr-1 for several decades. If the current rate of loss is not reduced, an additional 2,550 km2 of coastal wetlands will be lost by the year 2050. Currently, stormwater in Terrebonne Parish is pumped into canals, ultimately discharging into the Gulf of Mexico. An opportunity exists to use this stormwater for wetland restoration; however, the ecological impacts of stormwater diversions on wetlands are unknown. The objectives of this project were to 1) to investigate the seed banks of a degraded marsh to determine if a viable …

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Swimming Performance Of Juvenile Florida Pompano (Trachinotus Carolinus) And Atlantic Spadefish (Chaetodipterus Faber) Exposed To Sublethal Concentrations Of Ethylene Glycol And Methanol: Individual And Synergistic Effects, Mark Alan Stead Jan 2003

Swimming Performance Of Juvenile Florida Pompano (Trachinotus Carolinus) And Atlantic Spadefish (Chaetodipterus Faber) Exposed To Sublethal Concentrations Of Ethylene Glycol And Methanol: Individual And Synergistic Effects, Mark Alan Stead

LSU Master's Theses

Recently, new technology has pushed petrochemical exploration into increasingly deeper water (>305 m) at increased risks to marine fauna. One risk is from chemical additives used to enhance deepwater production such as ethylene glycol and methanol which are used during the production and treatment to prevent the formation of gas hydrates in deepwater wells and pipelines. Juvenile Florida pompano (Trachinotus carolinus) were used in controlled experiments to test the effects of 3.0 % ethylene glycol (EG), 1.07 % methanol (MeOH) and a combination of the two chemicals(EG + MeOH) on swimming performance of individual fish. Swimming performance was evaluated …

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The Effects Of Sediment Grain Size And Oil Exploration On Microbial Atp Biomass, Eric Tyson Guilbeau Jan 2003

The Effects Of Sediment Grain Size And Oil Exploration On Microbial Atp Biomass, Eric Tyson Guilbeau

LSU Master's Theses

Adenosine triphosphate (ATP) is a unique biochemical indicator of active microbial biomass and its relationship to environmental conditions. Its assay in sediments is complicated, however, by adsorptive loss to the sediment matrix and subsequent interferences in the luciferin-luciferase assay by compounds released during the extraction process. Corrections must be applied to correct for these losses and we describe a novel approach using radioactive ATP to correct for ATP adsorption. The sediment matrix also plays a significant role in determining both the magnitude of the ATP pool and the extent of the ATP adsorptive loss. Coarser sediments were found to have …

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Quantifying Habitat Quality Of Larval Bay Anchovy (Anchoa Mitchilli) In Chesapeake Bay By Linking An Individual-Based Model With Spatially-Detailed Field Data, Aaron Thomas Adamack Jan 2003

Quantifying Habitat Quality Of Larval Bay Anchovy (Anchoa Mitchilli) In Chesapeake Bay By Linking An Individual-Based Model With Spatially-Detailed Field Data, Aaron Thomas Adamack

LSU Master's Theses

Larval bay anchovy (Anchoa mitchilli) habitat quality in Chesapeake Bay was predicted using an individual-based model applied to spatially-detailed field data from Rilling and Houde (1999). Habitat quality was predicted using the ratio of instantaneous mortality rate to instantaneous growth rate. Model predictions of habitat quality were compared to field estimates of habitat quality derived from the spatially-detailed field data. Three sets of one-day simulations were performed to estimate larval growth and mortality rates throughout Chesapeake Bay during June and during July 1993. Field-based simulations used field data to estimate the model inputs of water temperature, zooplankton densities, and the …

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A Comparison Of Finfish Assemblages On Subtidal Oyster Shell (Cultched Oyster Lease) And Mud Bottom In Barataria Bay, Louisiana, John Plunket Jan 2003

A Comparison Of Finfish Assemblages On Subtidal Oyster Shell (Cultched Oyster Lease) And Mud Bottom In Barataria Bay, Louisiana, John Plunket

LSU Master's Theses

Recent research suggests that oyster reefs provide unique three-dimensional hard bottom habitat for many fish species. Along the northern shore of the Gulf of Mexico, oyster shell bottoms are predominantly flat, subtidal and cultched, lacking the vertical relief and spatial heterogeneity provided by natural reefs. This study compared finfish assemblages, gut contents, and macroinvertebrate assemblages at subtidal oyster shell (cultched oyster lease) and mud bottoms in Barataria Bay, Louisiana. Three mud and three shell sites were sampled on seven dates from October 2001 to October 2002, using gill nets and substrate trays. Data from the gill nets were used to …

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An Ecopath/Ecosim Analysis Of An Estuarine Food Web: Seasonal Energy Flow And Response To River-Flow Related Perturbations, Laura Lynette Althauser Jan 2003

An Ecopath/Ecosim Analysis Of An Estuarine Food Web: Seasonal Energy Flow And Response To River-Flow Related Perturbations, Laura Lynette Althauser

LSU Master's Theses

Estuaries are often the receiving basins for major river systems which makes them vulnerable to anthropogenic influences. I used Ecopath and Ecosim to investigate the structure of the Weeks Bay, Alabama, USA food web, and the responses of the food web to bottom-up perturbations. Four season-specific steady-state Ecopath models were developed and used to compare the production, biomass, consumption, biomass flows, and higher order indices of ecosystem functioning of the Weeks Bay food web under winter, spring, summer, and fall conditions. The season-specific Ecopath snapshots indicated that the structure of the Weeks Bay food web was resilient. Winter had the …

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Pulsed River Flooding Effects On Sediment Deposition In Breton Sound Estuary, Louisiana, Katherine Wheelock Jan 2003

Pulsed River Flooding Effects On Sediment Deposition In Breton Sound Estuary, Louisiana, Katherine Wheelock

LSU Master's Theses

Louisiana's deltaic coast is a dynamic sedimentary environment made vulnerable by Mississippi River channelization, which restricts freshwater, sediment, and nutrient inputs to adjacent estuaries. Freshwater diversions now reconnect some estuaries with historic fluvial sources, like Breton Sound basin, which receives Mississippi River suspended loads through the Caernarvon freshwater diversion. The project objectives were to quantify short-term sediment accumulation using sediment traps, evaluate sediment trap effectiveness, and compare long-term deposition using feldspar horizon markers and 210Pb dating to the annual sediment trap deposition. Magnitude and variations of sediment deposition at 14 sites were compared during an 18-month study in the upper …

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Sedimentation Rates And Metal Retention In An Urban Louisiana Swamp, Renee Lynn Sanders Jan 2002

Sedimentation Rates And Metal Retention In An Urban Louisiana Swamp, Renee Lynn Sanders

LSU Master's Theses

Naturally vegetated areas converted to urban uses increases impervious surfaces in a watershed with corresponding increases in nutrient, sediment, and metal loadings to downstream ecosystems. Wetlands mitigate detrimental impacts by transforming or retaining pollutants. Current and historic sedimentation and metal retention rates were measured in an urban, depressional wetland in Baton Rouge, Louisiana to evaluate landscape position and watershed development on these processes. Sedimentation disks, feldspar marker horizons, and Cs137 analyses were used in three distinct landscape positions. Inflow channels had the highest elevation and water velocity while the interior was located in the lowest elevations with the longest hydroperiod. …

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The Effects Of Fall Coldfront Passages On The Nekton Community In A Tidal Creek In Port Fourchon, La, As Monitored By Hydroacoustics, David J. Harmon Jan 2002

The Effects Of Fall Coldfront Passages On The Nekton Community In A Tidal Creek In Port Fourchon, La, As Monitored By Hydroacoustics, David J. Harmon

LSU Master's Theses

Split-beam hydroacoustic sampling with two, 420 KHz, 2x6 degree elliptical transducers was evaluated as a tool to quantify nekton movements in a Louisiana estuary. I measured the effects of atmospheric cold front passages on nekton in a tidal creek in Port Fourchon, LA during the fall of 2000. Six “fronts” were sampled between October 6 and December 18, 2000. Nekton density ranged from 0 to 24.4 fish/m3 with an overall mean of 2.44 fish/m3. Net samples were taken to supplement the acoustic data with species composition data. Species composition changed from October to December. A higher number …

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Feeding Habits Of Blacktip Sharks, Carcharhinus Limbatus, And Atlantic Sharpnose Sharks, Rhizoprionodon Terraenovae, In Louisiana Coastal Waters, Kevin Patrick Barry Jan 2002

Feeding Habits Of Blacktip Sharks, Carcharhinus Limbatus, And Atlantic Sharpnose Sharks, Rhizoprionodon Terraenovae, In Louisiana Coastal Waters, Kevin Patrick Barry

LSU Master's Theses

Little is known regarding the feeding behavior of many shark species. Even less is known about shark feeding habits in Louisiana coastal waters. The stomach contents of gillnet-captured blacktip sharks (n=356), Carcharhinus limbatus, and Atlantic sharpnose sharks (n=55), Rhizoprionodon terraenovae, were examined in this study. Roughly half of the blacktip stomachs (52%) and sharpnose stomachs (45%) contained prey items. The primary prey item in terms of percent number, occurrence, and weight for blacktips and sharpnose was the gulf menhaden, Brevoortia patronus. Both blacktips and sharpnose appear to mainly be piscivores; however, no members of Sciaenidae, the most common family of …

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The Importance Of Zooplankton In The Diets Of Blue Runner (Caranx Crysos) Near Offshore Petroleum Platforms In The Northern Gulf Of Mexico, Sean Francis Keenan Jan 2002

The Importance Of Zooplankton In The Diets Of Blue Runner (Caranx Crysos) Near Offshore Petroleum Platforms In The Northern Gulf Of Mexico, Sean Francis Keenan

LSU Master's Theses

Blue runner (Caranx crysos), common around offshore petroleum platforms in the Gulf of Mexico, were found to forage extensively on meso- and macro-zooplankton during the summer months. Larval decapods and stomatopods, hyperiid amphipods, pteropods, and larval and juvenile fishes were common components of their diet. Feeding periodicity results suggest that blue runner around platforms were capable of feeding throughout the night at the same intensity as the day. Size selectivity indicated that larger prey, such as fish were consumed during the night and smaller decapod crustaceans were consumed during the day. Blue runner collected from open waters away from platforms …

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Denitrification Potential Of Sediment From A Future Mississippi River Diversion Site In Louisiana, Roy Ryuta Iwai Jan 2002

Denitrification Potential Of Sediment From A Future Mississippi River Diversion Site In Louisiana, Roy Ryuta Iwai

LSU Master's Theses

Denitrification potential was determined in surface sediment from Lake Cataouatche, the receiving basin for a future Mississippi River diversion located in the northern portion of the Barataria Basin estuary. Nitrate removal and denitrification was measured in the laboratory using static sediment microcosms flooded with lake water. Dissolved potassium nitrate (KNO3) was added to the microcosms to achieve: 1) an initial nitrate concentration similar to the mean Mississippi River concentration (~1.4 mg NO3-N l-1), and, 2) a high initial nitrate concentration to elicit a denitrification potential (~50 mg NO3-N l-1). Denitrification …

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