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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 …

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 …

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 …

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 …

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 …

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 …

Freshwater Reservoir Offsets And Food Crusts: Isotope, Ams, And Lipid Analyses Of Experimental Cooking Residues, John P. Hart, Karine Taché, William A. Lovis

Publications and Research

Freshwater reservoir offsets (FROs) occur when AMS dates on charred, encrusted food residues on pottery predate a pot’s chronological context because of the presence of ancient carbon from aquatic resources such as fish. Research over the past two decades has demonstrated that FROs vary widely within and between water bodies and between fish in those water bodies. Lipid analyses have identified aquatic biomarkers that can be extracted from cooking residues as potential evidence for FROs. However, lacking has been efforts to determine empirically how much fish with FROs needs to be cooked in a pot with other resources to result …

Furs: Functionality, Fashion, And Franchise, Jenna Q. Detweiler

Environment and Sustainability Honors Papers

Animal furs have been used in various manners through human history. Early humans cut crude shawls for warmth, and with the development of tools such as needles, closer-fitting clothing such as fur pants became possible. As time went on, products such as wool and cotton were used for clothing and, with fur alternatives, furs were reserved for the ultra-wealthy in some cultures. The image of fur as a luxury item has remained ever since, but simultaneously fur has become more accessible to the general public. Meanwhile, animal rights movements have successfully dampened interest in fur in some countries and communities. …

Helping Farmers And Reducing Car Crashes: The Surprising Benefits Of Predators, Christopher O'Bryan, Eve Mcdonald-Madden, James Watson, Neil Carter

Human-Environment Systems Research Center Faculty Publications and Presentations

Humans may be Earth’s apex predator, but the fleeting shadow of a vulture or the glimpse of a big cat can cause instinctive fear and disdain. But new evidence suggests that predators and scavengers are much more beneficial to humans than commonly believed, and that their loss may have greater consequences than we have imagined.

First-Year Vitality Of Reforestation Plantings In Response To Herbivore Exclusion On Reclaimed Appalachian Surface-Mined Land, Zachary J. Hackworth, John M. Lhotka, John J. Cox, Christopher D. Barton, Matthew T. Springer

Forestry and Natural Resources Faculty Publications

Conventional Appalachian surface-mine reclamation techniques repress natural forest regeneration, and tree plantings are often necessary for reforestation. Reclaimed Appalachian surface mines harbor a suite of mammal herbivores that forage on recently planted seedlings. Anecdotal reports across Appalachia have implicated herbivory in the hindrance and failure of reforestation efforts, yet empirical evaluation of herbivory impacts on planted seedling vitality in this region remains relatively uninitiated. First growing-season survival, height growth, and mammal herbivory damage of black locust (Robinia pseudoacacia L.), shortleaf pine (Pinus echinata Mill.), and white oak (Quercus alba L.) are presented in response to varying intensities …

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 …

Spatial Processes Decouple Management From Objectives In A Heterogeneous Landscape: Predator Control As A Case Study, Peter J. Mahoney, Julie K. Young, Kent R. Hersey, Randy T. Larsen, Brock R. Mcmillan, David C. Stoner

Wildland Resources Faculty Publications

Predator control is often implemented with the intent of disrupting top‐down regulation in sensitive prey populations. However, ambiguity surrounding the efficacy of predator management, as well as the strength of top‐down effects of predators in general, is often exacerbated by the spatially implicit analytical approaches used in assessing data with explicit spatial structure. Here, we highlight the importance of considering spatial context in the case of a predator control study in south‐central Utah. We assessed the spatial match between aerial removal risk in coyotes (Canis latrans) and mule deer (Odocoileus hemionus) resource selection during parturition using …

Assessment Of Water Quality Variation In Rivers Through Comparative Index Technique And Its Reliability For Decision Making, Aldo Kitalika, Revocatus Machunda, Hans Komakech, Karoli N Njau

Tanzania Journal of Science

The National Sanitation Foundation (NSF) and Weighed Arithmetic Index (WAI) methods for water quality index (WQI) have been studied to evaluate their reliability in water quality assessment in rivers. Water samples were collected in various GPS predetermined points in Temi, Nduruma, Tengeru and Maji ya Chai rivers-Tanzania during wet and dry seasons and were analyzed for several water quality parameters using standard methods as per APHA. Medium to excellent water qualities were observed for pristine environment in three rivers except Maji ya Chai under NSF and WIA methods, respectively. Excellent water quality was observed in the pristine environment of Temi …

The Impact Of Land Use On Nitrate-N Movement And Storage In The Vadose Zone Of The Hastings’ Whpa, Craig Adams

School of Natural Resources: Dissertations, Theses, and Student Research

Nebraska has one of the largest agricultural economies in the United States and relies heavily on irrigation and fertilizer application to maintain crop yields. Over-irrigation and continuous application of nitrogen (N) in many areas has led to accumulation of nitrate-N in soils and sediments throughout the state’s vadose zone. Because nitrate-N is both persistent and mobile, groundwater concentrations in many areas of Nebraska and other agriculturally intensive states are increasing. Nitrate-N contamination of public and private drinking water supplies that utilize groundwater are of particular concern. Vadose zone sampling is an important method for rapidly assessing the effect of changing …

Downscaling Africa’S Drought Forecasts Through Integration Of Indigenous And Scientific Drought Forecasts Using Fuzzy Cognitive Maps, Muthoni Masinde, Mwanjele Mwagha, Tsegaye Tadesse

National Drought Mitigation Center: Faculty Publications

In the wake of increased drought occurrences being witnessed in Sub-Saharan Africa, more localized and contextualized drought mitigation strategies are on the agendas of many researchers and policy makers in the region. The integration of indigenous knowledge on droughts with seasonal climate forecasts is one such strategy. The main challenge facing this integration, however, is the formal representation of highly-structured and holistic indigenous knowledge. In this paper, we demonstrate how the use of fuzzy cognitive mapping can address this challenge. Indigenous knowledge on droughts from five communities was modeled and represented using fuzzy cognitive maps. Maps from one of these …

Algal Biofuel: The Future Of Green Jet Fuel In Air Transportation, Rajee Olaganathan

Publications

The aviation industry is one of the major contributors for the greenhouse gases. As air travel has become inevitable in this modern era, and fossil fuel usage is not sustainable, it is essential to produce renewable fuel and commercialize it to reduce the greenhouse gas emissions. In order to produce an alternate aviation biofuel a lot of industrial and academic collaborations have been developed worldwide. The main concern of this collaborative research is to produce aviation biofuel from renewable resources with low environmental impacts, and which is sustainable at an economically viable price. This mini-review briefly discusses the biotechnological approaches …

"Un-Designating" Marine Sanctuaries?: Assessing President Trump's America-First Offshore Energy Strategy, Kevin O. Leske

William & Mary Environmental Law and Policy Review

No abstract provided.

Does Scale Matter? A Systematic Review Of Incorporating Biological Realism When Predicting Changes In Species Distributions, Sydne Record, Angela L. Strecker, Mao-Ning Tuanmu, Lydia Beaudrot, Phoebe Zarnetske, Jonathan Belmaker, Beth Gerstner

Environmental Science and Management Faculty Publications and Presentations

Background: There is ample evidence that biotic factors, such as biotic interactions and dispersal capacity, can affect species distributions and influence species’ responses to climate change. However, little is known about how these factors affect predictions from species distribution models (SDMs) with respect to spatial grain and extent of the models.

Objectives: Understanding how spatial scale influences the effects of biological processes in SDMs is important because SDMs are one of the primary tools used by conservation biologists to assess biodiversity impacts of climate change.

Data sources and study eligibility criteria: We systematically reviewed SDM studies published …

Water Quality Assessment In The Santa Fe River: Tracking Pollution Sources Via Quantitative Polymerase Chain Reaction Analysis, Hayley Aurora Hajic

Geography ETDs

Microbial contamination affects many water bodies in the United States and pathogens associated with contamination pose a threat to human health. While the nation’s lakes, streams and rivers have been monitored for decades, many still do not meet the requirements of the 1972 Clean Water Act. Due to the number of pathogens that occur in water bodies, it is not feasible to directly monitor all of them. Instead of testing for a plethora of pathogens, it is standard practice for water divisions to monitor fecal indicator bacteria (FIB) as a proxy to determine water quality. There are significant flaws, however, …

Can Prescribed Fire Reduce Tick Parasitism Of Birds?, Leslie A. Sterling, Kim Medley, Katie Westby, Solný Adalsteinsson

Undergraduate Research Symposium Posters

Tick-borne diseases spread through enzootic transmission cycles that often involve ticks parasitizing bird hosts. Some avian species are competent reservoirs, amplifying the pathogens that cause tick-borne illnesses in humans. Prescribed burns in forests have the potential to reduce tick-borne disease risk if they limit interactions between ticks and infectious wildlife hosts. Although prescribed burns are increasingly being used for a variety of habitat management purposes, little is known about how they affect tick-host interactions. We hypothesize that if prescribed fires reduce tick abundance, then birds in burned forest plots will host fewer ticks than birds in unburned forest plots. Experimental …

Phenological Mismatch In Coastal Western Alaska May Increase Summer Season Greenhouse Gas Uptake, Katharine C. Kelsey, A. Joshua Leffler, Karen H. Beard, Ryan T. Choi, Joel A. Schmutz, Jeffery M. Welker

Wildland Resources Faculty Publications

High latitude ecosystems are prone to phenological mismatches due to climate change- driven advances in the growing season and changing arrival times of migratory herbivores. These changes have the potential to alter biogeochemical cycling and contribute to feedbacks on climate change by altering greenhouse gas (GHG) emissions of carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O) through large regions of the Arctic. Yet the effects of phenological mismatches on gas fluxes are currently unexplored. We used a three-year field experiment that altered the start of the growing season and timing of grazing to …

Waste Management By Waste: Removal Of Acid Dyes From Wastewaters Of Textile Coloration Using Fish Scales, S M Fijul Kabir

LSU Master's Theses

Removal of hazardous acid dyes by economical process using low-cost bio-sorbents from wool industry wastewaters is of a pressing need, since it causes skin and respiratory diseases and disrupts other environmental components. Fish scales (FS), a by-product of fish industry, a type of solid waste, are usually discarded carelessly resulting in pungent odor and environmental burden. In this research, the FS of black drum (Pogonias cromis) were used for the removal of acid dyes (acid red 1 (AR1), acid blue 45 (AB45) and acid yellow 127 (AY126)) from wool industry wastewaters by absorption process with a view to …

T.D.A. Cockerell (1866–1948) Of The University Of Colorado: His Contributions To The Natural History Of The California Islands And The Establishment Of Channel Islands National Monument, Daniel R. Muhs

United States Geological Survey: Staff Publications

Theodore Dru Alison Cockerell was a naturalist at the University of Colorado from 1904 to 1947 and studied botany, zoology, and paleontology in North and South America, Asia, Australia, Africa, and Europe. In the latter part of his career, he studied the California islands and published many papers on their natural history, 16 of them in four years (1937–1940). He made important contributions to the natural history of the islands in four distinct ways: entomology of the islands, including identification of a number of new species of bees; discovery of fossil marine invertebrate faunas and recognition that the zoogeography of …

The Effects Of Metal Speciation, Content And Cluster Size In Fly Ash On Pcdd/F Formation, Xia Guan

LSU Doctoral Dissertations

Transition metal oxides present in waste incineration systems have the ability to catalyze the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) through surface mediated condensation of organic dioxin precursors. Current studies have concentrated on the catalytic effects of individual transition metal oxides, while the complex composition of fly ash introduces the possibility of synergistic or antagonistic effects between multiple, catalytically active components. In addition, there is at present hardly a quantitative link between fly ash physical properties/chemical reactivity and PCDD/Fs yield.

We have tested fly ash surrogates containing different ratios of iron (III) oxide and copper (II) oxide …

Effects Of Enhanced Efficiency Nitrogen Fertilizers On Agronomic Parameters And Loss Pathways In The Subtropical Mississippi Delta Region, Scott Michael Pensky

LSU Master's Theses

Minimizing nitrogen (N) loss is critical for improving N use efficiency (NUE) in crop production and reducing its effects on the environment. Management practices such as seasonal application timing of N fertilizers and the addition of enhanced efficiency N fertilizers (EENFs) were investigated for the high N requirement of the two most common cereal crops globally, corn (Zea mays L.) and wheat (Triticum aestivum L.), in the subtropical climate of Louisiana. Field research was established during the 2016 and 2017 seasons at the LSU Agricultural Center’s Dean Lee and Central research stations to examine the effect of different EENFs and …

Relating Diets And Food Availability To Long-Term Population Trends Of Lesser Scaup Wintering On Lake Pontchartrain, Louisiana, Clay Michael Stroud

LSU Master's Theses

Lake Pontchartrain provides wintering habitat for a continentally-significant proportion of lesser scaup (Aythya affinis). Mid-winter aerial surveys indicate dramatic variation in annual scaup abundance (0–1,194,907), though the mechanisms driving fluctuations have not been previously investigated. In response to natural and anthropogenic disturbances, species composition, abundance, and size structure of benthic invertebrate populations in Lake Pontchartrain exhibit drastic variability among years. Given that wintering scaup feed primarily on mollusks, environmental disturbances have the potential to influence scaup dynamics on the estuary by altering the benthic community. To diagnose trophic linkages and variation in scaup abundance, we collected ducks (n=60) …