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Water And Solute Transport In The Shallow Subsurface Of A Riverine Wetland Natural Levee, April Elea Newman Jan 2010

Water And Solute Transport In The Shallow Subsurface Of A Riverine Wetland Natural Levee, April Elea Newman

LSU Master's Theses

In riverine wetlands, the rate and magnitude of water exchanged between river channels and adjacent wetlands have a major influence on hydrologic function and associated aquatic habitat and water quality. River channels are generally separated from backswamps by natural levees; however, preferential flow may allow potentially substantial water and solute exchange between them. Determining the influence of preferential flow on water and solute transport in natural levees requires an innovative approach that allows measurement of transport rates at a scale large enough to capture field-scale variability. To test the hypothesis that preferential flow is important to subsurface water movement through …


Status Of Wintering Grassland Birds In A Post-Hurricane, Salvage-Logged Forest, Matthew Edward Brooks Jan 2010

Status Of Wintering Grassland Birds In A Post-Hurricane, Salvage-Logged Forest, Matthew Edward Brooks

LSU Master's Theses

North American grassland birds have been declining at an alarming rate. Winter habitat for grassland species in the southeastern U.S. generally occurs within forests subject to management. I studied wintering grassland bird communities in De Soto National Forest in southern Mississippi. My objectives were to: 1) Assess bird communities and vegetation structure in upland forest stands that were salvage-logged following Hurricane Katrina, in stands managed for Red-cockaded Woodpeckers (Picoides borealis, RCW), and in stands containing bogs; and 2) Determine the extent of the association between vegetation and occurrence of the common wintering grassland birds. I conducted bird and vegetation surveys …


Impact Of Urban Runoff On Phosphorus, Nitrogen, And Dissolved Oxygen In A Shallow Subtropical Lake, Ryan Mesmer Jan 2010

Impact Of Urban Runoff On Phosphorus, Nitrogen, And Dissolved Oxygen In A Shallow Subtropical Lake, Ryan Mesmer

LSU Master's Theses

This research assessed the current conditions of water quality in a shallow subtropical lake, influenced by a highly developed urban environment. Specifically, the research focused on the dynamics of phosphorus, nitrogen, and dissolved oxygen, as well as the effects of stormwater runoff on lake water quality. Furthermore, the research quantified gross primary production, net primary production, and respiration in order to discern seasonal variation in lake metabolism. A water quality monitoring platform with multi-parameter probes was deployed in the center of University Lake on the Louisiana State University campus. A series of lake water quality parameters including dissolved oxygen (DO) …


Multi-Scale Habitat Associations Of Shorebirds During Spring Migration In Southwestern Louisiana Rice Fields, Rachel K. Villani Jan 2010

Multi-Scale Habitat Associations Of Shorebirds During Spring Migration In Southwestern Louisiana Rice Fields, Rachel K. Villani

LSU Master's Theses

Rice is the most common wetland crop in the world, and important for waterbirds and shorebirds worldwide, including the United States. In Louisiana, shorebirds use rice fields during spring migration, and are an important for foraging and refueling during migration. However, competing land uses and restoration projects may reduce the availability of rice fields, and impact the landscape that shorebirds use during migration. To determine how shorebirds use the landscape, I evaluated local and landscape factors affecting shorebird use of rice fields during spring migration in southwestern Louisiana. Using five habitat suitability zones (HSZs) based on rice density and canopy …


The Impact Of Hurricanes Katrina And Rita On The Louisiana Judicial System, Charles Simon Mccowan, Iii Jan 2010

The Impact Of Hurricanes Katrina And Rita On The Louisiana Judicial System, Charles Simon Mccowan, Iii

LSU Master's Theses

This thesis is a case study of the impact of Hurricanes Katrina and Rita on the Louisiana court system and the response of the court system to the aftermath of these two hurricanes. Although this thesis focuses on one state’s court system’s response to two natural disasters, the research, conclusions and recommendations are transferable to other states. Hurricanes Katrina and Rita struck the Gulf Coast in 2005 devastating large areas in Louisiana, Texas, Mississippi and Alabama. Millions of people, including judges and attorneys, were forced to evacuate their homes, courts and law offices. The Hurricanes caused interruptions to both federal …


Habitat Use, Movements And Spring Migration Chronology And Corridors Of Female Gadwalls That Winter Along The Louisiana Gulf Coast, Jacob M. Gray Jan 2010

Habitat Use, Movements And Spring Migration Chronology And Corridors Of Female Gadwalls That Winter Along The Louisiana Gulf Coast, Jacob M. Gray

LSU Master's Theses

The Louisiana Gulf Coast is an important wintering area for North American gadwall (Anas strepera). Conservation of winter habitat is a top priority of the Gulf Coast Joint Venture. Quantitative estimates of habitat use by wintering gadwall would help improve energetic demand models and subsequent estimates of habitat requirements. I used satellite telemetry (PTTs) to estimate winter habitat and refuge uses, spring migration chronology and corridors, as well as inter- and intra-regional winter movements of females. I used a split-plot MANOVA to evaluate the effects of individual females, female age, winter, hunt periods within winter, time of day, and all …


Impacts Of Marsh Loss And Fragmentation On Microhabitat Use By Estuarine Nekton In Southwest Louisiana, John Alexander Gordon Jan 2010

Impacts Of Marsh Loss And Fragmentation On Microhabitat Use By Estuarine Nekton In Southwest Louisiana, John Alexander Gordon

LSU Master's Theses

In Louisiana, the extensive loss and fragmentation of coastal marshes has prompted inquires into the impacts these processes may have on estuarine-dependant nekton. To date, research on nekton response to marsh loss and fragmentation has been limited to landscape-level studies which focus on the relationship between nekton productivity and the availability of marsh edge. These studies have relied on the assumption that marsh edges provide the same level of support to nekton regardless of the degree of surrounding marsh loss or fragmentation. This study tested this assumption by investigating the impacts of marsh loss and fragmentation on marsh-edge characteristics and …


Effectiveness Of Forestry Best Management Practices In Minimizing Harvesting Impacts On Streamflow And Sediment Loading In Low-Gradient Headwaters Of The Gulf Coastal Plain, Kristopher Brown Jan 2010

Effectiveness Of Forestry Best Management Practices In Minimizing Harvesting Impacts On Streamflow And Sediment Loading In Low-Gradient Headwaters Of The Gulf Coastal Plain, Kristopher Brown

LSU Master's Theses

Few studies have examined the effectiveness of timber harvesting Best Management Practices (BMPs) in water quality protection of widely-spread, low-gradient, and highly intermittent headwaters on the Gulf Coastal Plain. Also, a spatial disparity exists between the plot-scale water quality benefits afforded by BMP implementation and the watershed-scale with which most watershed stewardship programs are managed. In this thesis research, paired-watershed and Before-After-Control-Impact (BACI) designs were utilized to quantify plot- and watershed-scale changes in streamflow, as well as baseflow and stormflow Total Suspended Sediment (TSS) concentration and yield for 27 months after clearcut harvesting with and without BMPs in a low-gradient, …


Evaluating Remote Setting Techniques For Oyster (Crassostrea Virginica) Seed Production In Louisiana, Victoria D. Ippolito Jan 2010

Evaluating Remote Setting Techniques For Oyster (Crassostrea Virginica) Seed Production In Louisiana, Victoria D. Ippolito

LSU Master's Theses

Research was conducted to implement remote setting technology for the commercial- scale production of oysters on alternative cultch material in Louisiana. Genetic research has created an enhanced oyster stock for commercial cultivation. Since the Louisiana oyster industry relies on natural seed production for product, they are unable to utilize these new advances and are never guaranteed a reliable source of oyster seed. Remote setting is one way of producing a consistent supply of genetically improved oysters. Cultch material for oyster settlement is a limiting resource. Several alternatives to clamshell have been explored. The objectives of this study are: (1) test …


Effects Of Habitat Structural Complexity On Nekton Assemblages: Lab And Field Observations In Southern Louisiana, Austin T. Humphries Jan 2010

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 …


Introgression, Health, And Condition Of Florida, Northern, And Fx Hybrid Largemouth Bass In Louisiana Water Bodies, Melissa Ann Fries Jan 2010

Introgression, Health, And Condition Of Florida, Northern, And Fx Hybrid Largemouth Bass In Louisiana Water Bodies, Melissa Ann Fries

LSU Master's Theses

Since 1982, the Louisiana Department of Wildlife and Fisheries (LDWF) has stocked Florida-strain largemouth bass (FLMB; Micropterus salmoides floridanus) to incorporate Florida alleles into native populations (NLMB; M. s. salmoides) and enhance recreational fishing opportunities. I collected habitat data and largemouth bass samples from 12 LDWF stocked reservoirs and disconnected oxbow lakes to examine the relationships between reservoir characteristics, genetic identity, relative weight (Wr), liver somatic index (LSI), parasite loads, and back-calculated length-at-age. I examined the relationships between water body and genetic identity with Wr, LSI, and back-calculated length-at-age by ANOVA. Parasite loads were analyzed with ordinal regression. Principle component …


The Influence Of Two Estrogens On The Sex And Ovarian Development Of Eastern Oysters (Crassostrea Virginica) Maintained In A Closed Recirculating System, Wesley Michael Burnside Jan 2010

The Influence Of Two Estrogens On The Sex And Ovarian Development Of Eastern Oysters (Crassostrea Virginica) Maintained In A Closed Recirculating System, Wesley Michael Burnside

LSU Master's Theses

As a multi-million dollar industry, production of the eastern oyster Crassostrea virginica is significant to the economy of the nation’s coastal regions. The cost of commercial oyster aquaculture has higher inputs than the oyster fishery, but larger, better quality oysters can be produced for culture by the stable availability of triploid individuals.

The goal of this project was to determine if the use of an estrogen, estradiol-17β or estradiol-3-benzoate, at a consistent environmental temperature would increase the percentage of females in a population, as well as ovarian development of eastern oysters. Ultimately, this could be applied to triploids to increase …


Bioaerosols And The Risk Of Upper Respiratory Infection In Dental Hygienists, Christen Rebecca Gautreau Jan 2010

Bioaerosols And The Risk Of Upper Respiratory Infection In Dental Hygienists, Christen Rebecca Gautreau

LSU Master's Theses

Multitudes of pathogenic and infectious microbes are known to spread via contaminated aerosols. Dental personnel have an increased incidence of respiratory infections. Ultrasonic scaling procedures are reported to produce the largest amounts of contaminated aerosols of any dental procedure. The goal of the current study was to see if dental hygienists are at an increased risk of respiratory infections during the performance of their job and to see if certain dental procedures had a significant effect on this risk. This study was conducted at the Dental Hygiene Clinic of the Louisiana State University School of Dentistry in New Orleans, LA. …


Rapid Microwave-Assisted Acid Extraction Of Chromate Copper Arsenate (Cca)-Treated Southern Pine, Bin Yu Jan 2010

Rapid Microwave-Assisted Acid Extraction Of Chromate Copper Arsenate (Cca)-Treated Southern Pine, Bin Yu

LSU Master's Theses

Recovery of heavy metals from chromated copper arsenate (CCA) treated southern pine wood samples with three different dimension was investigated by recovery with acetic acid, oxalic acid and phosphoric acid in microwave reactor. Diluted phosphoric acid mixed with acetic acid was found to be very effective to remove copper, chromium, and arsenic from spent CCA-treated southern pine sawdust at a high temperature and in a short time. No single acid can totally recover all these three metals in one step in this method. Oxalic acid was effective in removing chromium and arsenic, and acetic acid was effective in removing copper …


Predicting First Year Seedling Survival From Quality Distributions Of Bareroot Seedlings And Microsites, Puskar Nath Khanal Jan 2010

Predicting First Year Seedling Survival From Quality Distributions Of Bareroot Seedlings And Microsites, Puskar Nath Khanal

LSU Master's Theses

Seeding survival has been a continuing problem since the start of the commercial pine plantation in 1950s. The first-year survival of bare-root loblolly pine seedlings at intensively prepared sites in Louisiana has reached a survival plateau of 75 to 85 % with an average of almost 80 %. The major hypothesis of this research was that the survival plateau is a function of the interaction between the frequency distribution of seedling quality and the frequency distribution of microsite quality. This study examined bare-root seedlings and microsite variation, and analyzed the possible options to increase the first-year seedling survival. The study …


Influences On Public Support For Green Infrastructure: An Examination Of Urban Wetland Restoration In Post-Katrina New Orleans, Lynette C. Overholser Jan 2010

Influences On Public Support For Green Infrastructure: An Examination Of Urban Wetland Restoration In Post-Katrina New Orleans, Lynette C. Overholser

LSU Master's Theses

The research examines patterns of likely support for urban wetland restoration in the Greater New Orleans area. Through multi-variate statistical analysis of responses derived from an original survey of homeowners in New Orleans, key factors are identified that explain variation in residents’ willingness to accept such areas and their perceptions of ecological benefits associated with a theoretical wetlands restoration design for the Gentilly area. Further, the analysis determines the extent to which direct experience with Hurricane Katrina may influence public support for this and other green infrastructure projects. The results of the data collected show that many people in New …


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 …


Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron Jan 2010

Upland Nesting Waterfowl Population Responses To Predator Reduction In North Dakota, Matthew R. Pieron

LSU Doctoral Dissertations

Population growth for mallards (Anas platyrhynchos), and presumably other upland nesting ducks, in the Prairie Pothole Region is most sensitive to nest success, and nest success is most strongly influenced by predation. I evaluated the efficacy of reducing predator populations to improve nest success and increase local breeding populations of upland nesting ducks on township-sized (93.2 km2) management units in eastern North Dakota, USA, during 2005−2008. I also examined potential territorial limitations on local population growth for mallards. Trappers annually removed an average of 245 predators per trapped site. I monitored 7,489 nests on 7 trapped and 5 nontrapped sites, …


Public Perception Of Wildfire Risk And Prescribed Burning In The Wildland/Urban Interface Of The Louisiana Florida Parishes, Charlotte Ann Gerald Jan 2010

Public Perception Of Wildfire Risk And Prescribed Burning In The Wildland/Urban Interface Of The Louisiana Florida Parishes, Charlotte Ann Gerald

LSU Master's Theses

Wildfire has been suppressed in the nation’s forests for over a hundred years. The accumulation of forest fuels over time has created an urgent need to reduce fuel loads to prevent catastrophic wildfires from occurring, not only in our wildlands, but also in our Wildland/Urban Interfaces (WUI’s). The residents who live within the WUI are particularly vulnerable to extreme wildfire events. As cities become more densely populated, increasing numbers of people are moving beyond the suburbs into the WUI. A complex matrix of structures and forested land, developing communities, and impinging forests exists within the WUI. This study utilized a …


Spatial Analyses Of Pedosphere Carbon Stock And Sequestration Potential In Louisiana's Watersheds, Biao Zhong Jan 2010

Spatial Analyses Of Pedosphere Carbon Stock And Sequestration Potential In Louisiana's Watersheds, Biao Zhong

LSU Doctoral Dissertations

This dissertation research aimed to quantify current soil organic carbon (SOC) stocks across Louisiana’s landscape, examine the spatial relationships between SOC and terrain factors at the watershed and river basin scales, and predict SOC changes in surface soils during future climate change. Using Louisiana as an example, a spatially-explicit modeling framework was developed that is conducive to watershed-scale prediction of soil carbon stock and change. SOC densities at the watershed scale were estimated using the USDA NRCS Soil Geographic Database (STATSGO). Louisiana watersheds and National Land Cover Database (NLCD) were used to aggregate total soil carbon and estimate average soil …


Age Related Productivity And Consistency Of Nest Initiation Timing Of Wild Mallards In Eastern North Dakota, Timothy Charles Kimmel Jan 2010

Age Related Productivity And Consistency Of Nest Initiation Timing Of Wild Mallards In Eastern North Dakota, Timothy Charles Kimmel

LSU Master's Theses

Mallards Anas platyrhnchos are arguably the most researched waterfowl species in North America. They exhibit great flexibility in certain breeding metrics such as timing of nest initiation and clutch size. A study on captive female Mallards (Batt and Prince 1979) fed ad libitum, held in identical breeding compartments, and paired with the same mate in each year of the study exhibited substantial variation in the timing of nest initiation within a given year, yet some individual females demonstrated consistency in initiation date among years. My objective was to examine breeding metrics such as timing of nest initiation and clutch size …


Early Life History Dynamics Of The Fish Community In The Atchafalaya River Basin, B. Thorpe Halloran Jan 2010

Early Life History Dynamics Of The Fish Community In The Atchafalaya River Basin, B. Thorpe Halloran

LSU Doctoral Dissertations

Seasonal overbank flooding in systems like the Atchafalaya River Basin (ARB) provides the opportunity for fishes in the mainstem to access off-channel areas on the floodplain. Typically, newly inundated floodplain habitats allow adult fishes to add biomass, avoid predation, and potentially, to reproduce. However, in systems like the ARB, the timing, duration, and magnitude of flooding infrequently coincides with known reproductive periods of many fishes assumed to be floodplain-dependent. To quantify the level of floodplain-exploitative fish reproduction in the ARB, I collected larval and juvenile fish with a variety of sampling gear that allowed estimates in both ultra-shallow (< 2-m) and continuously-inundated habitats (headwater lakes, canals, and bayous). A suite of water quality parameters, river stage, flow, and hours of daylight were used to gauge the influence of environmental phenomena on age-0 abundance during both inundation and drawdown. The results of the 19-month study suggest that many taxa do not rely on the floodplain to ensure high survivorship. Interestingly, the reproductive ecologies of many ARB fishes appeared to be largely independent of widespread connectivity. Although an increasing hydrograph appeared to enhance reproductive output, the interannual timing and intensity of spawning showed limited variability. Larval densities were also contrasted with the microcrustacean zooplankton (copepods and cladocerans) population to assess if a potential food limitation existed in the weeks and months following hatching. During the study, increased zooplankter abundance was typically preceded by elevated river-floodplain connectivity. Conversely, as floodwaters receded during the summer, zooplankton abundance declined to lowest levels observed during the study. Overall, there was limited synchronous overlap between the hatchlings of most fish taxa and their zooplankter prey. This could have potentially resulted in starvation and reduced annual recruitment. Yet, my analysis of the factors that regulate larval fish abundance in the ARB suggest that the density of zooplankton was highly significant although high numbers of larvae and zooplankton rarely coincided. Finally, I compared the intraday (morning vs. afternoon) density and mean length of larval fish at fixed sample sites. The results suggest that once-daily ichthyoplankton collections may fail to provide accurate density and length measurements for young fish populations.


Developing Tools To Identify Factors That Limit Production In Coastal Marshes, Vanessa Danielle Tobias Jan 2010

Developing Tools To Identify Factors That Limit Production In Coastal Marshes, Vanessa Danielle Tobias

LSU Doctoral Dissertations

Marsh loss is a problem in many areas around the world. In Louisiana’s coastal marshes, where Spartina patens is the most common plant, restoration and management seek to slow wetland loss rates that average approximately 77.4 km2/year. To combat the problem, scientists and managers require tools to determine local causes and evaluate the effectiveness of management techniques. Current methods for identifying factors that limit productivity in marshes are too time-consuming or expensive for wide-spread, regular use. Critical values of elemental concentrations in plant tissue are widely used to diagnose mineral deficiencies and toxicities in agricultural crops, however. I used the …


The Effects Of Channel Stability On Benthic Macroinvertebrates In Southeastern Louisiana Streams, Peter Markos Jan 2010

The Effects Of Channel Stability On Benthic Macroinvertebrates In Southeastern Louisiana Streams, Peter Markos

LSU Master's Theses

Water chemistry, habitat quality, and channel stability interact to influence a stream’s biological integrity. The goal of this project was to assess how channel stability, together with other physicochemical stream measurements, are associated with the structure and abundance of resident macroinvertebrate communities. I recorded multiple physicochemical parameters and calculated a Pfankuch habitat stability index monthly for a year at potential reference streams in southeastern Louisiana. I assessed the relationships of channels stability with measured physicochemical parameters with multiple regression and principle components analysis. Mixed model multivariate analysis of variance was used to determine associations of habitat characteristics with resident macroinvertebrate …