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The Effect Of Channel Stability On Fish Condition And Diet In Thompson Creek, La, Alexia Lagrone Apr 2022

The Effect Of Channel Stability On Fish Condition And Diet In Thompson Creek, La, Alexia Lagrone

Honors Theses

No abstract provided.


Marginal Warming Associated With A Covid-19 Quarantine And The Implications For Disease Transmission, P. W. Miller, C. Reesman, M. K. Grossman, S. A. Nelson, V. Liu, P. Wang Jan 2021

Marginal Warming Associated With A Covid-19 Quarantine And The Implications For Disease Transmission, P. W. Miller, C. Reesman, M. K. Grossman, S. A. Nelson, V. Liu, P. Wang

Faculty Publications

During January-February 2020, parts of China faced restricted mobility under COVID-19 quarantines, which have been associated with improved air quality. Because particulate pollutants scatter, diffuse, and absorb incoming solar radiation, a net negative radiative forcing, decreased air pollution can yield surface warming. As such, this study (1) documents the evolution of China's January-February 2020 air temperature and concurrent particulate changes; (2) determines the temperature response related to reduced particulates during the COVID-19 quarantine (C19Q); and (3) discusses the conceptual implications for temperature-dependent disease transmission. C19Q particulate evolution is monitored using satellite analyses, and concurrent temperature anomalies are diagnosed using surface …


Micropaleontological Record Of A Preserved, Late Pleistocene Bald Cypress Forest On The Northern Gulf Of Mexico Inner Shelf, Jonathan Thien Truong May 2018

Micropaleontological Record Of A Preserved, Late Pleistocene Bald Cypress Forest On The Northern Gulf Of Mexico Inner Shelf, Jonathan Thien Truong

LSU Master's Theses

A cluster of previously buried Taxodium distichum stumps are exposed and preserved in growth position at the bottom of a trough on the inner Gulf of Mexico (GOM) continental shelf in 18 m water depth and 13 km offshore Orange Beach, AL. Radiocarbon ages from wood and optically stimulated luminescence (OSL) dating of sediments suggest a Marine Isotope Stage (MIS) 3 age, or older. This study builds on the previous work of Gonzalez (2018) and Obeclz (2017). Five biofacies were identified in vibracore collected in 2015 and 2016: 1) the Holocene Mississippi-Alabama-Florida (MAFLA) sand sheet, 2) a Holocene interbedded sand …


Condition Of Birds In Amazonian Rainforest Fragments And Second-Growth Forests, Angelica Maria Hernandez Palma Jan 2017

Condition Of Birds In Amazonian Rainforest Fragments And Second-Growth Forests, Angelica Maria Hernandez Palma

LSU Doctoral Dissertations

Deforestation modifies otherwise intact expanses of forest into small, isolated fragments. In addition to fragmentation, deforestation also creates abrupt forest edges and large areas of regenerating vegetation where land is abandoned after clearing. Understanding how changes in the landscape affect the physical condition of birds is crucial for managing populations in human-modified landscapes. Here I use the biomarkers feather growth rate and feather quality (ptilochronology), fluctuating asymmetry (FA), and stress hormones from feathers (CORT), to estimate the physical condition of Amazonian understory birds living in forest fragments, second-growth forests, and continuous forests. Feather CORT revealed how fragmentation disrupts interspecific interactions; …


Human Gut Microbiota And Obesity: How Is Gut Microbiota Associated With Obesity Improvement Induced By Bariatric Surgeries Or Low-Calorie Diet Treatment?, Rui Zhang Jan 2017

Human Gut Microbiota And Obesity: How Is Gut Microbiota Associated With Obesity Improvement Induced By Bariatric Surgeries Or Low-Calorie Diet Treatment?, Rui Zhang

LSU Doctoral Dissertations

An increasing number of studies suggest that the complex microbial community of the human gut may have an important role in human health and disease conditions such as obesity and diabetes. However, the causal relationship among gut microbiota, obesity, weight loss, and the influence of bariatric surgery remains largely unknown. This study investigated the correlation between human gut microbiota and obesity via determining how gut microbiota is associated with obesity improvement induced by bariatric surgeries (BRS) and low-calorie diet (LCD) treatment. Specifically, we investigated the effects of various bariatric surgery (BRS) procedures and a low-calorie diet (LCD) treatment on the …


Influence Of The Mississippi River On Pseudo-Nitzschia Spp. Abundance And Toxicity In Louisiana Coastal Waters, Sibel Bargu, Melissa M. Baustian, Nancy N. Rabalais, Ross Del Rio, Benjamin Von Korff, R. Eugene Turner Mar 2016

Influence Of The Mississippi River On Pseudo-Nitzschia Spp. Abundance And Toxicity In Louisiana Coastal Waters, Sibel Bargu, Melissa M. Baustian, Nancy N. Rabalais, Ross Del Rio, Benjamin Von Korff, R. Eugene Turner

Faculty Publications

The presence of domoic acid (DA) toxin from multiple species of Pseudo-nitzschia is a concern in the highly productive food webs of the northern 1,* 2,3 2 1 1,4 1 1 2 3 4 Gulf of Mexico. We documented the Pseudo-­nitzschia presence, abundance, blooms, and toxicity over 3 years along a transect ∼100 km west of the Mississippi River Delta on the continental shelf. Pseudo-nitzschia were present throughout the year and occurred in high abundances (>10 cells l ) in the early spring months during high Mississippi River (MSR) flow (∼20,000 m s ) but were most abundant ( …


Evaluating Survival Of Released Ranched American Alligator In Coastal Louisiana, Kristy Durham Capelle Jan 2016

Evaluating Survival Of Released Ranched American Alligator In Coastal Louisiana, Kristy Durham Capelle

LSU Master's Theses

Since 1986, Louisiana’s American alligator (Alligator mississippiensis) ranching program has required the release of alligators produced from eggs collected from wild nests to maintain wild populations. This project assessed long-term harvest data (1991-2010s) to estimate survival of released alligators. First, wildlife and fishery harvest models and general inter-disciplinary survival models were evaluated to determine best fit to the data. Second, once the best fitting model was selected, release length, precipitation and temperature from release sites, and an index of hunter effort were added to investigate influences on survival estimates. Release length was included because over time the proportion and size …


Site-Specific Habitat And Landscape Associations Of Rusty Blackbirds Wintering In Louisiana, Sinead Mary Borchert Jan 2015

Site-Specific Habitat And Landscape Associations Of Rusty Blackbirds Wintering In Louisiana, Sinead Mary Borchert

LSU Master's Theses

The Rusty Blackbird (Euphagus carolinus) has gained notoriety in recent years as one of the fastest declining North American bird species, with a global population loss of as much as 95%. Causes of the decline are not completely understood, but the high rate of forested wetland change in the southeastern United States suggests that wintering habitat degradation may be a primary driver. To better inform management on critical wintering grounds, I surveyed 68 sites in Louisiana where Rusty Blackbirds had been known to occur to address how occupancy changes with habitat type and colonization and extinction rates vary with ground …


The Effects Of Tropical Storms And Hurricanes On Phytoplankton And Nutrient Concentrations In Wetland-Estuary Transition Zones Along The Gulf Coast, Tiffany Chantelle Johnson Jan 2015

The Effects Of Tropical Storms And Hurricanes On Phytoplankton And Nutrient Concentrations In Wetland-Estuary Transition Zones Along The Gulf Coast, Tiffany Chantelle Johnson

LSU Master's Theses

Two consecutive storms made landfall along the Northern Gulf of Mexico on June and August 2012 (Tropical Storm Debby, 06/26/2012; Isaac, 08/28/2012, Category (Cat) 1 Saffir-Simpson Hurricane Scale). Each storm passed within 48 to 273 km of one of seven wetland-estuary transition zone sampling sites, and indirect storm effects associated with changes in freshwater discharge and an inflow of inorganic nutrients were observed at five of the seven sites. To assess the impacts of the 2012 hurricanes on hydrology, nutrient concentrations, and phytoplankton concentrations at transition zones along the Gulf Coast, a within-sites analysis along with a seasonal analysis were …


Preliminary Multifactorial Analysis Of Parkinson's Disease, Max James Miller Jan 2014

Preliminary Multifactorial Analysis Of Parkinson's Disease, Max James Miller

LSU Master's Theses

Neurodegenerative disorders affect millions of Americans every year. Incidence increases as the human population ages. Parkinson’s Disease, a neurodegenerative disorder in the dopaminergic system of the basal ganglia, causes deterioration of movement as the disease progresses. Researchers have attempted to figure out what causes PD and are currently examining it as an environmental disease. This study examined PD as an environmental disease using a multifactorial approach. Methods included 1) utilization of hospital and mortality records in order to investigate a relationship between occupation and PD 2) using ArcGIS 10.2 technology to examine the spatial components of PD 3) conducting Chi-Square …


Dgge Analysis Of Denitrifying Bacterial Diversity In Response To Nutrients And Oil Contamination In Salt Marshes, Catalina Restrepo Jan 2014

Dgge Analysis Of Denitrifying Bacterial Diversity In Response To Nutrients And Oil Contamination In Salt Marshes, Catalina Restrepo

LSU Master's Theses

Salt marsh ecosystems located at the Mississippi River delta are exposed to high levels of point and nonpoint sources of nutrients such as nitrate-based fertilizers and to oil spills in the Gulf of Mexico. However, there is little information on the effects of eutrophication and oil contamination on the bacterial diversity of denitrifying bacteria in salt marsh sediments of coastal Louisiana. The effects of excess nutrients on the bacterial diversity of denitrifiers were analyzed by injecting sediment cores with high concentrations of nitrate (100μM NO3- and 20,000μM NO3-) and carbon (0% and 20% C concentration from the original sample). After …


Some Effects Of Nutrient And Flooding Stress Manipulation On Coastal Louisiana Wetland Vegetation, James Stephen Ialeggio Jan 2013

Some Effects Of Nutrient And Flooding Stress Manipulation On Coastal Louisiana Wetland Vegetation, James Stephen Ialeggio

LSU Master's Theses

Freshwater diversions are a relatively recently utilized tool in wetland loss mitigation that stimulate an organic accretion response in marsh vegetation, which is based in root production and thus belowground biomass. The effectiveness of freshwater diversions in slowing marsh loss probably varies across a gradient of the factors they supply: decreased salinity, increased nutrient concentrations, and increased inundation. Flooding stress is commonly thought to be the overriding factor limiting wetland vegetation growth, however its influence may vary across salinity and nutrients. Therefore, plugs of Spartina patens were planted in four “marsh organs” consisting each of 36 sediment-filled PVC pipes of …


Effects Of Physicochemical Properties And Macrohabitat On The Foraging Ecology And Condition Of The Centrarchid Assemblage Of The Atchafalaya River Basin, Louisiana, Brett A. Miller Jan 2013

Effects Of Physicochemical Properties And Macrohabitat On The Foraging Ecology And Condition Of The Centrarchid Assemblage Of The Atchafalaya River Basin, Louisiana, Brett A. Miller

LSU Master's Theses

The Atchafalaya River Basin (ARB), Louisiana supports a diverse centrarchid assemblage, characterized by abundant populations of largemouth bass Micropterus salmoides, black crappie Pomoxis nigromaculatus, warmouth Lepomis gulosus, bluegill Lepomis macrochirus, redspotted sunfish Lepomis miniatus, longear sunfish Lepomis megalotis and redear sunfish Lepomis microlophus. This dynamic floodplain ecosystem is comprised of a mosaic of macrohabitats, including natural bayous, shallow lakes, dead-end and open pipeline canals. I conducted an extensive feeding ecology study to determine the influence of these macrohabitats on foraging activity through stomach content and stable isotope analyses. I collected 2,036 centrarchids with electrofishing efforts in the summers of 2011 …


The Feasibility Of Using Vanadium And Nickel To Track Oil Spills In Coastal Environments, Sean Patrick Kenny Jan 2013

The Feasibility Of Using Vanadium And Nickel To Track Oil Spills In Coastal Environments, Sean Patrick Kenny

LSU Master's Theses

Crude oil has been increasing in world demand over the past century. It is known that oil is resistant to weathering processes and if spilled, can cause serious environmental damage to an area, on land or sea. A complementary approach to current methods of tracking oil and identifying spill-impacted sediments may be to measure trace metals associated with crude oil. Trace metals, such a vanadium (V) and nickel (Ni) are known to be elevated in concentration in some oil sources, but little work has been done on this topic. This research explored less expensive and time-consuming methods to track or …


Characterization Of Epibenthic And Demersal Megafauan At Mississippi Canyon 252 Following The Deepwater Horizon Oil Spill, Marla Maxine Valentine Jan 2013

Characterization Of Epibenthic And Demersal Megafauan At Mississippi Canyon 252 Following The Deepwater Horizon Oil Spill, Marla Maxine Valentine

LSU Master's Theses

Increased demand for new sources of oil and gas has resulted in an expansion of drilling into deeper waters. With this exploratory drilling come increased risks, which were realized on April 20, 2010 when the blow out preventer on the Macondo Well failed, resulting in the release of a large quantity of oil and gas into the Northern Gulf of Mexico from a bathypelagic source. This unprecedented environmental disaster was coined the Deepwater Horizon Oil Spill by the popular news media. In the months that followed the spill, the lack of knowledge about the pre-spill condition of deep-sea communities in …


Impacts Of Artificial Reef Addition On The Nekton Community Of Louisiana Marsh Ponds: A Before-After-Control-Impact Analysis, Kari Elizabeth Klotzbach Jan 2013

Impacts Of Artificial Reef Addition On The Nekton Community Of Louisiana Marsh Ponds: A Before-After-Control-Impact Analysis, Kari Elizabeth Klotzbach

LSU Master's Theses

Louisiana’s coastal estuaries are dynamic, highly variable environments that provide nursery areas for numerous recreationally and commercially important species. Louisiana’s coastline is constantly changing due to natural and anthropogenic processes, and it is important to know how nektonic species are impacted by such changes. This study sought to assess the effects of introducing a hard substrate artificial reef on the nekton community of a Louisiana estuary. A before-after-control-impact (BACI) design was used to assess the impacts of artificial reef addition on nektonic fishes and crustaceans in four shallow marsh ponds near Empire, Louisiana. Marsh ponds were sampled by purse seine …


Community Resilience To Coastal Hazards : An Analysis Of Two Geographical Scales In Louisiana, Chi Li Jan 2013

Community Resilience To Coastal Hazards : An Analysis Of Two Geographical Scales In Louisiana, Chi Li

LSU Master's Theses

Quantifying resilience is difficulties due to the different definitions of resilience, the interchangeable uses with two other terms “vulnerability” and “adaptability”, as well as the lack of consensus on what indicators should be selected to quantifying resilience. This thesis research studied the community resilience in Louisiana by applying the Resilience Inference Measurement (RIM) model at two geographic levels: county level and zip code level. The RIM model accesses resilience by using three dimensions (exposure, damage, and recovery) and two abilities (vulnerability and adaptability). The types of coastal hazards included in this study were: coastal, flooding, hurricane/tropical storm, tornado, and severe …


Function And Diversity Of The Ship, Trinity, And Tiger Shoal Complex, With Emphasis On Macrofauna And Spawning Blue Crabs (Callinectes Sapidus), Carey George Gelpi Jr. Jan 2012

Function And Diversity Of The Ship, Trinity, And Tiger Shoal Complex, With Emphasis On Macrofauna And Spawning Blue Crabs (Callinectes Sapidus), Carey George Gelpi Jr.

LSU Doctoral Dissertations

The ecological and economic value of sandy shoals off the Louisiana coast is not well understood. During three years of comprehensive benthic sampling and environmental measurements I studied the Ship, Trinity, Tiger Shoal Complex (STTSC), which comprises changing and discrete benthic habitats including high relief sandy shoals, and muddier, mostly deeper off-shoal areas, prone to hypoxia. Benthic macrofaunal assemblages of shoals included endemic species, and shoal communities were significantly different from each other and the muddier offshoal habitat, contributing to northern Gulf of Mexico (GoM) regional biodiversity. Sand percentage was the most influential environmental parameter shaping macrofaunal community composition across …


The Distribution And Diversity Of Functional Gene Pathways Controlling Sulfur Speciation In Lower Kane Cave, Wyoming, Audrey Tarlton Paterson Jan 2012

The Distribution And Diversity Of Functional Gene Pathways Controlling Sulfur Speciation In Lower Kane Cave, Wyoming, Audrey Tarlton Paterson

LSU Master's Theses

Defining the linkages between microbial metabolic activity and environmental geochemistry can be used to understand how carbonate dissolution in sulfidic karst systems proceeds. In Lower Kane Cave, Wyoming, sulfidic springs support taxonomically distinct microbial communities that are also associated with putative sulfur metabolisms (e.g., oxidation of reduced sulfur compounds, sulfate reduction, and sulfur disproportionation) that influence carbonate dissolution. The distribution of diverse microbial groups in other terrestrial subsurface environments is not well understood, making Lower Kane Cave ideal for study. Molecular genetics techniques were used to uncover diversity of 16S rRNA genes and bacterial soxB and aprA functional genes. Aqueous …


Biomass And Mass Balance Isotope Content Of Mussel Seep Populations, Philip Martin Riekenberg Jan 2012

Biomass And Mass Balance Isotope Content Of Mussel Seep Populations, Philip Martin Riekenberg

LSU Master's Theses

Cold seep mussels, Bathymodiolus childressi, are common cold seep constituents that form large populations at upper continental slope (500-1000 m) cold seep sites in the Northern Gulf of Mexico. These mussels utilize methane present through symbiotic relationships with methanotrophic bacteria. This study uses a coupled isotope technique to determine the relative incorporation of respiratory carbon in the shell as a measure of the availability of methane between different seep sites. This method indicates a higher abundance of methane at the Brine Pool site than at the Bush Hill site which appears significantly more resource limited and that changes in methane …


Modeling The Population Effects Of Hypoxia On Atlantic Croaker (Micropogonias Undulatus) In The Northwestern Gulf Of Mexico, Sean Brandon Creekmore Jan 2011

Modeling The Population Effects Of Hypoxia On Atlantic Croaker (Micropogonias Undulatus) In The Northwestern Gulf Of Mexico, Sean Brandon Creekmore

LSU Master's Theses

The northwestern Gulf of Mexico currently experiences a large hypoxic area (“dead zone”) during the summer. While the local effects of hypoxia on organisms have been documented, the population-level effects are largely unknown. I developed a spatially-explicit, individual-based model to analyze how hypoxia effects on Atlantic croaker reproduction, growth, and mortality in the northwestern Gulf of Mexico could lead to population-level responses. The model follows the hourly growth, mortality, reproduction, and movement of individuals on a 300 x 800 spatial grid of 1 km2 cells for 100 years. Chlorophyll-a concentration, water temperature, and dissolved oxygen were specified daily for each …


Temporal Changes In Quality Of Life And Environment In New Orleans After Hurricane Katrina, Danielle Johanna Larock Jan 2011

Temporal Changes In Quality Of Life And Environment In New Orleans After Hurricane Katrina, Danielle Johanna Larock

LSU Master's Theses

Understanding and assessing the spatial and temporal changes of quality of life and environment of a community is critical to its sustainable development, especially after a disaster strikes. This study explores an approach that integrates remote sensing with socioeconomic data to assess the temporal changes in quality of life and environment (QOL) using Orleans Parish as an example. Hurricane Katrina, which struck New Orleans in 2005, has had vast implications economically, socially, and environmentally for this city and the surrounding area. Empirically quantifying these concepts will help to rebuild the city more sustainably. This study investigated change in environmental quality …


Understanding The Use Of Barrier Islands As Nesting Habitat For Louisiana Birds Of Concern, Cecilia Marie Leumas Jan 2010

Understanding The Use Of Barrier Islands As Nesting Habitat For Louisiana Birds Of Concern, Cecilia Marie Leumas

LSU Master's Theses

Colonial nesting seabirds are threatened by habitat loss and degradation, human disturbance, predation, and climate change. Several species of conservation concern concentrate high percentages of their total U.S. populations in Louisiana breeding colonies. We studied seabirds, including Royal Terns, Sandwich Terns, and Black Skimmers, nesting on Isles Dernieres barrier islands along the Gulf coast of Louisiana. Two of the four islands in this chain host extensive seabird colonies and two do not. We used an experimental approach to test the hypothesis that large terns and skimmers are prevented from nesting on Trinity Island, the largest of the Isles Dernieres, by …


Patterns Of Habitat Suitability And Abundance Trends Of Current And Candidate Coastal Fish Species Of Concern In Louisiana, Elin Rose Sandy Jan 2010

Patterns Of Habitat Suitability And Abundance Trends Of Current And Candidate Coastal Fish Species Of Concern In Louisiana, Elin Rose Sandy

LSU Master's Theses

Louisiana’s estuaries and coastal waters play an important role in providing habitat for several estuarine-dependent species and also serve as a nursery for the juveniles of several other species. The current rate of land loss in Louisiana and the decline of estuarine-dependent species force us to improve our understanding of the recruitment of these species into Louisiana’s estuaries. Habitat suitabilities were developed for several fish species of concern (SOC) and other estuarine-dependent species across three environmental gradients, abundance patterns were developed for seasons, five-year intervals, and coastal study areas (CSAs). Chi-square analyses and ANOVAs were then used to test for …


The Role Of Climate Variability And Riverine Pulsing In The Community Dynamics Of Estuarine Nekton In Breton Sound, Louisiana, Bryan Patrick Piazza Jan 2009

The Role Of Climate Variability And Riverine Pulsing In The Community Dynamics Of Estuarine Nekton In Breton Sound, Louisiana, Bryan Patrick Piazza

LSU Doctoral Dissertations

Climate controls biotic community composition at multiple spatiotemporal scales through variability in environmental control mechanisms (assembly filters). This research investigated the role of climate variability in the community dynamics of estuarine nekton in Breton Sound estuary, Louisiana, and, specifically the effects of El Niño Southern Oscillation (ENSO), freshwater discharge, and a tropical cyclone. A teleconnection was found between ENSO and juvenile brown shrimp (Farfantepenaeus aztecus) abundance in Breton Sound from 1988 – 2007. ENSO affected winter weather conditions (air pressure, temperature and precipitation), and spring brown shrimp abundance in Breton Sound. Juvenile brown shrimp abundance lagged ENSO by …


Supercritical Fluid Extraction And Analysis Of Plant Oils, Tianchuan Du Jan 2009

Supercritical Fluid Extraction And Analysis Of Plant Oils, Tianchuan Du

LSU Master's Theses

Supercritical fluid extraction (SFE) of oxeye daisy (Chrysanthemum leucanthemum L.) seed, heartwood of Port-Orford cedar (POC) (Chamaecyparis lawsoniana), Alaska yellow cedar (AYC) (Chamaecyparis nootkatensis), and Eastern red cedar (ERC) (Juniperus virginiana L), and Chinese tallow (Sapium sebiferum L. Roxb. ) seed was investigated in this study and compared with other extraction methods. For the oxeye daisy seed extraction, Soxhlet extraction (SE) with hexane, microwave assisted extraction (MAE), and supercritical fluid extraction (SFE) were conducted. The results showed that as the extraction temperature decreased from 100 °C, the extraction rate increased until 30 °C using SFE. With an increase of extraction …


A Comparison Of Individual-Based And Matrix Projection Models To Applied To Fish Population And Community Dynamics, Shaye Ellen Sable Jan 2007

A Comparison Of Individual-Based And Matrix Projection Models To Applied To Fish Population And Community Dynamics, Shaye Ellen Sable

LSU Doctoral Dissertations

Matrix projection models and individual-based models (IBM) are commonly used for the analysis and management of fish populations. Matrix models break down the population into age or stage classes, while IBMs track individuals. I perform a series of quantitative comparisons between the predictions of the two modeling approaches using the IBM as the standard of comparison to demonstrate when individual variation, species interactions, and spatial heterogeneity adversely affect matrix model performance. I first evaluate the matrix approach for predicting yellow perch population responses when perch are involved in size-specific predator-prey interactions with walleye. I created density-dependent and stochastic age-structured and …


Modeling The Effects Of Endocrine Disrupting Chemicals On Atlantic Croaker: Understanding Biomarkers And Predicting Population Responses, Cheryl Anne Murphy Jan 2006

Modeling The Effects Of Endocrine Disrupting Chemicals On Atlantic Croaker: Understanding Biomarkers And Predicting Population Responses, Cheryl Anne Murphy

LSU Doctoral Dissertations

A number of environmental stressors have been shown to interfere with reproductive and behavioral processes of fish by interfering with endocrine function. Most biomarkers of endocrine disturbance tend to be static measurements from dynamic systems making them difficult to evaluate within the context of an individual, or subtle effects that do not relate well to endpoints of ecological significance. I present an approach that uses a series of models, based on Atlantic croaker, to extrapolate laboratory results to indicators of individual and population health. First, I created a physiologically based model that simulates vitellogenesis in a female fish. The model …


Dendrochronological Analysis Of Productivity And Hydrology In Two Louisiana Swamps, John Blake Amos Jan 2006

Dendrochronological Analysis Of Productivity And Hydrology In Two Louisiana Swamps, John Blake Amos

LSU Master's Theses

Modified river flows and land subsidence have subjected many coastal swamp forests in the delta of the Mississippi River to greatly altered flooding, sediment, and nutrient regimes. These areas have become inundated to greater depth, duration, and frequency and either are connected to the river and receive drastically increased sediment and nutrients (riverine swamps) or have become disconnected from riverine flooding (stagnant swamps) and receive little or no sediment and nutrient input. To better understand how these changes are affecting ecosystems, dendrochronological techniques for baldcypress (Taxodium distichum L. Rich.) were used at three sites in each of two contrasting swamps …


Macroinvertebrate Community Of Ecology Of Lowland, Subtropical Streams In Louisiana, Michael Douglas Kaller Jan 2005

Macroinvertebrate Community Of Ecology Of Lowland, Subtropical Streams In Louisiana, Michael Douglas Kaller

LSU Doctoral Dissertations

Freshwater ecosystems, particularly streams and rivers, have been the subject of prodigious research. Unfortunately, in comparison to neighboring regions, the Gulf of Mexico coastal plain has not received as much attention. Therefore, I collected data on the macroinvertebrates of these streams to begin the understanding of the relationships between community structure and environmental characteristics. In contrast to the hypothesized ancestral streams of these macroinvertebrates, coastal plain streams are commonly devoid of rocks leaving only woody debris as usable hard substrates and are typically lower in dissolved oxygen. I examined habitat selection by colonization of woody debris with large and small …