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Spatial And Temporal Trends In Diet For Pinfish (Lagodon Rhomboides) From Turtle Grass (Thalassia Testudinum) Beds With Contrasting Environmental Regimes In The Lower Laguna Madre, Texas, Maximiliano Barbosa

Theses and Dissertations

Seagrass meadows in far South Texas are dominated by turtle grass (Thalassia testudinum), and juvenile pinfish (Lagodon rhomboides) are abundant grazers of seagrass epifauna. As they grow, pinfish exhibit an ontogenetic dietary shift and begin consuming increasing amounts of plant material. In this study, contrasting environmental regimes in two seagrass meadows were examined to identify how they might affect pinfish diets, diet shifts, and growth across the growing season. The eastern site was sheltered from prevailing southeasterly winds by a barrier island, while the western site was shallower and subjected to higher wind energy and turbidity. …

Comparative Analysis Of Survival And Decay Of Fecal Indicator Bacteria In Bovine Feces And Freshwater Microcosms, Reem Tariq

Electronic Theses and Dissertations

Agricultural runoff can carry FIB that can pollute surface waters through the soil matrix. This study was designed to inspect the impact of temperature and matrix on the survival of FIB. The FIB were routinely enumerated over an 18-day period from fecal samples and freshwater microcosms maintained at 4oC, 22oC, and 35oC. It was found that the FIB studied underwent a primary growth of up to 1-log10 to 3-log10, highlighting the weakness of conventional FIB as indicators of pathogen contamination. The concentrations of FIB in the water phase were found to be significantly greater than those observed in the fecal …

Performance Assessment Of Solid State Anaerobic Digestion Of Poultry Litter, Mason Puckett

Biological and Agricultural Engineering Undergraduate Honors Theses

The disposal of poultry litter can exert an economic and environmental burden to the agriculture community. As a result, it is desirable to reduce the amount of waste and recover resources from the waste. This study focuses on the construction and preliminary testing of a laboratory scale (20 L) solid state anaerobic digester (AD) fed with dry poultry litter. Glucose was added in addition to the poultry litter to achieve the appropriate C:N ratio to support the growth of anaerobic microorganisms. The AD was first fed every 4 days at 4 g VS/L/feeding for 24 days, rested (no feeding) for …

Soil Organic Carbon And Mineralization Rates At The Woolsey Wet Prairie Mitigation Site In Fayetteville, Arkansas, Zachary Tipton

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Atmospheric carbon dioxide (CO2) levels are higher than ever recorded, surpassing 400 ppm in 2013, from a pre-industrial revolution level of around 280 ppm. Researchers have been looking at methods to mitigate high CO2 levels in the atmosphere, including promoting carbon sequestration in soils. Carbon sequestration is the process where CO2 is naturally or artificially transferred out of the atmosphere and stored in the ocean, plant biomass, soils, and geologic formations. Seemingly contradictory to the notion of carbon sequestration, is the use of fire as a management treatment for the restoration of native prairie grass ecosystems. Fire combusts plant biomass …

Municipal Drinking Water Quality: Environmental Health And Safety Perceptions In Phoenix, Arizona, Chelsey Weaver

Capstone Experience: Master of Public Health

The goals of the Service Learning/Capstone Experience (SL/CE) project included identifying current perceptions regarding lead in municipal drinking water and related environmental health and safety concerns in the Sunnyslope community of Phoenix, Arizona; evaluating and improving the current outreach program in order to effectively target drinking water perceptions; and identifying strengths and weaknesses in the City of Phoenix Water Services Department (WSD) and Environmental Services Division (ESD) that contribute to negative public perceptions of municipally supplied drinking water. Objectives used to meet the stated goals included developing and distributing a survey to measure perceptions of the above issues through a …

Impacts Of Hydroelectric Dams On Aquatic Macroinvertebrate Oviposition Strategies: The Role Of Desiccation, Jesse R. Fleri

Undergraduate Honors Capstone Projects

Previous studies quantifying the density, distribution and diversity of aquatic insects overwhelmingly focus on larval life stages. However, many aquatic insects exhibit selective oviposition behaviors, with a preference for emergent substrates along a river's edge. The practice of hydropeaking creates an artificial intertidal zone that is absent from natural rivers and to which freshwater organisms are not adapted. We hypothesized that this novel disturbance could reduce the availability and temporal persistence of oviposition habitats resulting in egg mortality. To test this hypothesis, we quantified the oviposition behavior of four aquatic insects using a hierarchical field survey of habitat availability and …

Breeding Season Ecology And Demography Of Lesser Scaup (Aythya Affinis) At Red Rock Lakes National Wildlife Refuge, Jeffrey M. Warren

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

It is hypothesized that individuals make reproductive decisions based on current assessments of their physiological condition and environmental conditions. For female lesser scaup (Aythya affinis), breeding occurs after an energetically costly spring migration. Increasing fat reserves (i.e., ‘body condition’) prior to breeding allows a female to produce a larger clutch of eggs, but time spent gaining body condition is costly in terms of time allowed to raise ducklings before freezing conditions in the fall. In Chapter 2 I explored rate of pre-breeding body condition gain in female lesser scaup, and how that rate influenced clutch size. Spring phenology, …

Outbreak And Extinction Dynamics In Stochastic Populations, Garrett T. Nieddu

Theses, Dissertations and Culminating Projects

Each piece of work herein examines nonlinear population dynamics using methods from deterministic dynamical systems, stochastic processes and statistical mechanics. This dissertation is the compilation of three independent – but related – pieces of work: the first investigates an isolated population that is capable of maintaining multiple carrying capacities; the second project examines a stochastic Ebola model with a zoonotic disease reservoir; and the third looks at a basic disease-invasion model to characterize outbreak vulnerability and the connectedness of supposedly separate populations.

Each of these three chapters explore the interplay between interconnected systems, without explicitly modeling the elements that are …

Phytochemical Screening, Elemental Composition And In Vitro Antioxidant Assessment Of Selected Uae Medicinal Plants, Amina Mukhtar Dirir

Biology Theses

Medicinal herbs have been used since prehistoric times to alleviate pain and to treat many different diseases. In recent decades, there has been a growing interest in natural product research, particularly on herbal plants and their bioactive constituents. The resurgence of interest in medicinal plants is primarily attributed to the inefficacy of synthetic medicines in combating many diseases as well as to their toxic and side effects. The flora of the UAE is rich with various medicinal plants that were utilized by the indigenous people for different therapeutic purposes. Unfortunately, there are still gaps of knowledge, research and development on …

Greenhouse Gas Emissions And Management Practices That Affect Emissions In Us Rice Systems, Bruce A. Linquist, Mathias Marcos, M. Arlene Adviento-Borbe, Merle Anders, Dustin Harrell, Steve Linscombe, Michele L. Reba, Benjamin R.K. Runkle, Lee Tarpley, Allison Thomson

Biological and Agricultural Engineering Faculty Publications and Presentations

Previous reviews have quantified factors affecting greenhouse gas (GHG) emissions from Asian rice (Oryza sativa L.) systems, but not from rice systems typical for the United States, which often vary considerably particularly in practices (i.e., water and carbon management) that affect emissions. Using meta‐analytic and regression approaches, existing data from the United States were examined to quantify GHG emissions and major practices affecting emissions. Due to different production practices, major rice production regions were defined as the mid‐South (Arkansas, Texas, Louisiana, Mississippi, and Missouri) and California, with emissions being evaluated separately. Average growing season CH4 emissions for the mid‐South and …

Towards Quantifying Relevant Land Cover Change: A Case Study In The Central Flyway Of The Monarch Butterfly, Hanna Lenee Ford

Graduate Theses and Dissertations

Over the past 20 years notable decreases in monarch butterfly populations have led researchers to begin evaluating the landscape for changes and seeking out opportunities for enacting conservation programs to better support their survival. The monarch butterfly has recently come under consideration for listing under the Endangered Species Act which has created a need for a more informed view of the landscape through which the migrate and breed, the central United States. In this research three spatially-explicit models are explored using the most applicable datasets currently available to address pressing policy and land manager decisions regarding monarch butterfly and pollinator …

Characterization Of Bacteriorhodopsin And Halorhodopsin Reconstituted In Lipid Bilayer Membranes, Joel Domkam Kamwa

Graduate Theses and Dissertations

Motivated to produce electricity with photon activated ion pumps, the main purpose of this work was to characterize the photosynthetic membrane proteins bacteriorhodopsin (proton pump) and halorhodopsin (chloride pump). The proteins were re-suspended in lipid bilayers. For this work, an experimental set-up was built which included: chambers for lipid bilayer formation and characterization, lasers for ion pump activation, and an AxoPatch electrophysiology system for small photocurrent measurement. Lipid bilayer membranes were formed using mostly folding method: folding two monolayers together. The membranes were characterized by their resistance, capacitance, and generated photocurrent. Photocurrent was generated upon illumination of lipid-protein membranes with …

Evaluating Outcomes Of An Immersive-Field-Study Program On Fifth-Grade Students’ Connectedness With Nature, Laleh Talebpour

Doctoral Dissertations

The purpose of this research was to investigate to what extent an immersive-field-study experience influenced fifth-grade students’ connection to nature. Two instruments were used to collect data: Connection to Nature Index (CNI) obtained pre- and postfield study and students’ field journals with prompts.

The coding of the journals was based on the four components of CNI: Enjoyment of Nature, Empathy for Creatures, Sense of Oneness, and Sense of Responsibility. These components were built on the three basic components of nature connectedness described by Schultz (2002) as “cognitive (connectedness), affective (caring), and behavioral (commitment)” (p. 61).

Data were gathered from 317 …

Message In A Bottle: The Expression And Confirmation Of Isf6_4831, A Polyethylene Terephthalate Hydrolase, Nathan A. Koconis

Graduate Theses

Polyethylene terephthalate (PET), the polyester used to make plastic bottles for soft drinks, is one of the top five sources of plastic waste in the world. Its abundance represents significant problems for municipalities and environments. Recycling PET polymers by traditional methods is possible, but success has been limited due to poor compliance, liability, cost, and other factors. Fortunately, a PET degradation pathway has been identified in Ideonella sakaiensis. Research on this pathway is still nascent and has not yet explored the PET hydrolase gene (ISF6_4831, or PETase) with its leading signal peptide intact. For this reason, the gene was transferred …

Extraction Of Metazoan Meiofauna From Muddy Deep-Sea Samples: Operator And Taxon Effects On Efficiency, Melissa Rohal, David Thistle, Erin E. Easton

School of Earth, Environmental, & Marine Sciences Faculty Publications

Deep-sea metazoan meiofaunal specimens are usually extracted from muddy samples by centrifugation in a fluid in which meiofauna tend to float and sediment particles tend to sink. Although the procedure is in common use, its efficiency has seldom been examined. The study reported here showed that well-trained operators extracted metazoan meiofauna with efficiencies that were different enough to be a concern in quantitative studies. Therefore, samples should be assigned to operators in a stratified-random manner. In the course of these studies, both operators also extracted individuals of the common nematode family Desmoscolecidae significantly less efficiently than other nematode families, a …

A Comparison Of Four Wetlands Assessment Procedures Relevant To The Alluvial Valleys Of East Texas, Amy Camp

Electronic Theses and Dissertations

Currently several methods are used by public and private entities to assess wetland functional condition in support of the Section 404 Clean Water Act program. Four of these are: Forested Wetlands in Alluvial Valleys of the Coastal Plain of the Southeastern United States (SEHGM); A Regional Guidebook for Applying the Hydrogeomorphic Approach to the Functional Assessment of Forested Wetlands in Alluvial Valleys of East Texas (ETXHGM); Texas Rapid Assessment Method (TXRAM); and the Wildlife Habitat Appraisal Procedure (WHAP). Little previous research compares wetland functional assessment methods. Results of the SEHGM, ETXHGM, TXRAM, and WHAP methods were compared on five East …

Advancing The Understanding Of Environmental Transformations, Bioavailability And Effects Of Nanomaterials, An International Us Environmental Protection Agency—Uk Environmental Nanoscience Initiative Joint Program, Mitch M. Lasat, Kian Fan Chung, Jamie Lead, Steve Mcgrath, Richard J. Owen, Sophie Rocks, Jason M. Unrine, Junfeng Zhang

Plant and Soil Sciences Faculty Publications

Nanotechnology has significant economic, health, and environmental benefits, including renewable energy and innovative environmental solutions. Manufactured nanoparticles have been incorporated into new materials and products because of their novel or enhanced properties. These very same properties also have prompted concerns about the potential environmental and human health hazard and risk posed by the manufactured nanomaterials. Appropriate risk management responses require the development of models capable of predicting the environmental and human health effects of the nanomaterials. Development of predictive models has been hampered by a lack of information concerning the environmental fate, behavior and effects of manufactured nanoparticles. The United …

How Effluent Compares To Storm Runoff In Relation With Surface Water Quality, Nicholas Krebs

D.U.Quark

Waste water treatment plants are considered simple solutions for poor surface water quality and are used in every developed and developing society. There are varying types of waste treatment plants. The systems are rarely able to purify all water that passes through the system. The problem with a mix-and-treat waste water system is the strain from sudden influxes of water. Systems that combine storm runoff accept variability in the volume of water that needs treating. Effluent is discharged when the plant cannot treat all the waste. The purpose of this review is to determine which system is the closest to …

Building Up Biogeography: Pattern To Process, William D. Pearse, A. Marcia Barbosa, Susanne A. Fritz, Sally A. Keith, Luke J. Harmon, John Harte, Daniele Silvestro, Xiao Xiao, T. Jonathan Davies

Ecology Center Publications

Linking pattern to process across spatial and temporal scales has been a key goal of the field of biogeography. In January 2017, the 8th biennial conference of the International Biogeography Society sponsored a symposium on Building up biogeography—process to pattern that aimed to review progress towards this goal. Here we present a summary of the symposium, in which we identified promising areas of current research and suggested future research directions. We focus on (1) emerging types of data such as behavioral observations and ancient DNA, (2) how to better incorporate historical data (such as fossils) to move beyond what we …

Disequilibrium Of Fire-Prone Forests Sets The Stage For A Rapid Decline In Conifer Dominance During The 21st Century, Josep M. Serra-Diaz, Charles Maxwell, Melissa S. Lucash, Robert M. Scheller, Danelle M. Laflower, Adam D. Miller, Alan J. Tepley, Howard E. Epstein, Kristina J. Anderson-Teixeira, Jonathan R. Thompson

Environmental Science and Management Faculty Publications and Presentations

As trees are long-lived organisms, the impacts of climate change on forest communities may not be apparent on the time scale of years to decades. While lagged responses to environmental change are common in forested systems, potential for abrupt transitions under climate change may occur in environments where alternative vegetation states are influenced by disturbances, such as fire. The Klamath mountains (northern California and southwest Oregon, USA) are currently dominated by carbon rich and hyper-diverse temperate conifer forests, but climate change could disrupt the mechanisms promoting forest stability– regeneration and fire tolerance— via shifts in the fire regime in conjunction …

Restoration Of Legacy Trees As Roosting Habitat For Myotis Bats In Eastern North American Forests, Michael J. Lacki

Forestry and Natural Resources Faculty Publications

Most eastern North American Myotis roost in forests during summer, with species forming maternity populations, or colonies, in cavities or crevices or beneath the bark of trees. In winter, these bats hibernate in caves and are experiencing overwinter mortalities due to infection from the fungus Pseudogymnoascus destructans, which causes white-nose syndrome (WNS). Population recovery of WNS-affected species is constrained by the ability of survivors to locate habitats suitable for rearing pups in summer. Forests in eastern North America have been severely altered by deforestation, land-use change, fragmentation and inadvertent introduction of exotic insect pests, resulting in shifts in tree …

Evaluating The Impact Of Eastern Hemlock Decline On Louisiana Waterthrush Demographics And Behavior In Great Smoky Mountains National Park, Lee Cotten Bryant

Student Theses and Dissertations

Eastern hemlock (Tsuga canadensis) is declining throughout the eastern United States due to the invasive hemlock woolly adelgid (Adelges tsugae Annand). In the southern Appalachians, hemlock is concentrated in moist ravines and its loss threatens riparian specialists and habitat quality. The Louisiana waterthrush (Parkesia motacilla) is an obligate-riparian species that could be sensitive to hemlock condition in the southern Appalachians, but how hemlock decline might impact it is currently unknown. I addressed this knowledge gap by evaluating relationships between hemlock decline and waterthrushes. First, I evaluated the ultimate effects hemlock decline could have on waterthrushes, focusing on survival and habitat …

The Firece Green Fire: Vol. 8 Issue 23, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.

Plant Biodiversity In The Face Of Climate Change: What Will Become Of Coastal Endemic Species?, Nila Le

Creative Activity and Research Day - CARD

How will longitudinally constrained coastal flora fare in the face of rapid anthropogenic climate change and disturbance? Coastal communities pose a unique problem for climate change and its associated risks. Species that are concentrated along the coast are naturally vulnerable to the influence of harsh abiotic ecology, such as coastal erosion and high salt concentrations. In addition, analogous to montane species-habitat interactions, coastal communities may be “pushed” off the coast edge as a result of tracking preferred climate in the face of climate variability and sea level rise. This can be problematic for species that cannot disperse quickly enough to …

Devonian Stromatoporoid Interactions At The Falls Of The Ohio State Park, Clarksville, Indiana, Morgan Sierra Hall

Undergraduate Theses

Stromatoporoids are calcitic sponges that occurred in the fossil record from the Early Ordovician to Late Devonian period. These sponges interacted with other organisms, especially rugose and tabulate corals. Some corals appear to benefit from the rigidity of stromatoporoids in response to turbulent waters. Stromatoporoids and many corals went extinct during the Frasnian-Famennian crisis when paleoenvironmental parameters were shifting. Studying the relationships between these taxa may provide insight to their vulnerability during the extinction.

This research was performed at the Falls of the Ohio in Clarksville, Indiana. Organisms in the Coral Zone were studied using transect sampling. Each fossil along …

Analysis Of Environmental Dna Methods For The Detection Of Small Stream Fishes, Taylor Kristen Lee

Student Theses and Dissertations

Analysis of environmental DNA (eDNA) represents a promising new tool geared toward assisting species detection, though there is still much to learn about its utility and robustness. The main objective of this study was to use eDNA with several other applied techniques to determine the presence of the federally threated Leopard Darter, Percina pantherina, within two tributaries of the Little River in Arkansas. Traditional field sampling failed to detect P. pantherina, and putative contamination prevented confident eDNA detection. My second objective used a spike experiment strategy to test the ability of the eDNA method to reliably detect low levels of …

An Assessment Of Atmospheric And Meteorological Factors Regulating Red Sea Phytoplankton Growth, Wenzhao Li, Hesham El-Askary, Mohamed A. Qurban, Emmanouil Proestakis, Michael J. Garay, Olga V. Kalishnikova, Vassilis Amiridis, Antonis Gkikas, Eleni Marinou, Thomas Piechota, K. P. Manikandan

Mathematics, Physics, and Computer Science Faculty Articles and Research

This study considers the various factors that regulate nutrients supply in the Red Sea. Multi-sensor observation and reanalysis datasets are used to examine the relationships among dust deposition, sea surface temperature (SST), and wind speed, as they may contribute to anomalous phytoplankton blooms, through time-series and correlation analyses. A positive correlation was found at 0–3 months lag between chlorophyll-a (Chl-a) anomalies and dust anomalies over the Red Sea regions. Dust deposition process was further examined with dust aerosols’ vertical distribution using satellite lidar data. Conversely, a negative correlation was found at 0–3 months lag between SST anomalies …

Assessment Of Mercury Content In Louisiana's Freshwater Fish And Its Association To Se Concentrations, Alexander David Reyes-Avila

LSU Master's Theses

Ample evidence has demonstrated the neurotoxic properties of organic Hg to humans. However, recent studies have proposed the protective effects of Se against organic Hg detected in marine fish. Louisiana’s freshwater bodies are exploited by recreational anglers that enjoy fishing as recreational activity and food source. Thus, testing of Hg in Louisiana was resumed in 2017 to update the state advisories. However, before drawing conclusions based solely on organic Hg, it might be useful to see how much Se is present in freshwater fish. The main objective of this study was to determine the Se:Hg molar ratio in Louisiana’s freshwater …

Quantifying Transport Of Passive Tracers And Inertial Particles In Geophysical Flows, Eric Forgoston

Sustainability Seminar Series

There has been a steady increase in the deployment of autonomous underwater and surface vehicles for applications such as ocean monitoring, tracking of marine processes, and forecasting contaminant transport. The underwater environment poses unique challenges since robots must operate in a communication and localization-limited environment where their dynamics are tightly coupled with the environmental dynamics. This work presents current efforts in understanding the impact of geophysical fluid dynamics on underwater vehicle control and autonomy. The focus of the first part of the talk is on the control of collaborative vehicles to track Lagrangian coherent structures and to localize contaminant spills. …

Wetland Conservation Effects Result In Enhanced Playa Functionality In The Rainwater Basin, Nebraska, Hong Zhang

Community and Regional Planning Program: Theses

This study assessed the functionality level of wetland hydrology, hydrophyte and soil conditions, and then identified the restorable potential of conserved playas. The distribution of hydrology and hydrophyte were geospatially examined through annual tracking the quantity and quality of wetlands on historical hydric soil footprints under different conservation programs in the Rainwater Basin (RWB) in Nebraska, USA during 2004-2015. The results show that the historical hydric soil footprints with the conservation programs had significantly higher functionality of ponded water and hydrophyte than non-conserved wetlands. The yearly average of ponded water areas within footprints varies at 12.59% for the Waterfowl Production …