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Full-Text Articles in Ecology and Evolutionary Biology

Hgs-3 The Influence Of A Tandem Cycling Program In The Community On Physical And Functional Health, Therapeutic Bonds, And Quality Of Life For Individuals And Care Partners Coping With Parkinson’S Disease, Leila Djerdjour, Jennifer L. Trilk Apr 2024

Hgs-3 The Influence Of A Tandem Cycling Program In The Community On Physical And Functional Health, Therapeutic Bonds, And Quality Of Life For Individuals And Care Partners Coping With Parkinson’S Disease, Leila Djerdjour, Jennifer L. Trilk

SC Upstate Research Symposium

Purpose Statement: Several studies have shown that aerobic exercise can have a positive impact on alleviating symptoms experienced by individuals with Parkinson's disease (PD). Despite this evidence, the potential benefits of exercise for both PD patients and their care partners (PD dyad) remain unexplored. This research project investigates the effectiveness, therapeutic collaborations, and physical outcomes of a virtual reality (VR) tandem cycling program specifically designed for PD dyads.

Methods: Following approval from the Prisma Health Institutional Review Board, individuals with PD were identified and screened by clinical neurologists. The pre-testing measures for PD dyads (N=9) included emotional and cognitive status …


The Impacts Of Environment And Host Evolutionary Relationships On Lemur Microbiota, Rachel B. Burten Mar 2024

The Impacts Of Environment And Host Evolutionary Relationships On Lemur Microbiota, Rachel B. Burten

Doctoral Dissertations

Recent studies have shown that the mammal microbiome is modified by environmental conditions, and that reduced microbiome functionality is associated with host health issues. Microbiome data in wild and captive primate populations can therefore be used to assess their health as they encounter a variety of environments. Comparative studies of the microbiome can also inform disease ecology, conservation, and captive management strategies tailored to different primate species. Therefore, this study examines how the hair, oral, and gut microbiota of nine wild and captive lemur species are determined by host phylogenetic relationships and host environment. I found that host species identity …


Materials And Methods Developed For The Recording And Analysis Of Behavior In The Common Marmoset (Callithrix Jacchus)., Christian Wintle Mar 2024

Materials And Methods Developed For The Recording And Analysis Of Behavior In The Common Marmoset (Callithrix Jacchus)., Christian Wintle

UNO Student Research and Creative Activity Fair

Materials and methods developed for the recording and analysis of behavior in the common marmoset (Callithrix jacchus).

Christian J. Wintlea, Jordan B. Hernandeza,b,c, Dobromir Dotovd, and Jonathan B. Claytona,b,e,f,g

aDepartment of Biology, University of Nebraska at Omaha, Omaha, NE, USA

bNebraska Food for Health Center, University of Nebraska-Lincoln, Lincoln, NE, USA

cDepartment of Genetics, Cell Biology, and Anatomy, University of Nebraska Medical Center, NE, USA

dDepartment of Biomechanics, University of Nebraska at Omaha, Omaha, NE, USA

eDepartment of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, …


A Comparison Of Adenosine Triphosphate With Other Metrics Of Microbial Biomass In A Gradient From The North Atlantic To The Chesapeake Bay, Alexander B. Bochdansky, Amber A. Beecher, Joshua R. Calderon, Alison N. Stouffer, Nyjaee N. Washington Jan 2024

A Comparison Of Adenosine Triphosphate With Other Metrics Of Microbial Biomass In A Gradient From The North Atlantic To The Chesapeake Bay, Alexander B. Bochdansky, Amber A. Beecher, Joshua R. Calderon, Alison N. Stouffer, Nyjaee N. Washington

OES Faculty Publications

A new, simplified protocol for determining particulate adenosine triphosphate (ATP) levels allows for the assessment of microbial biomass distribution in aquatic systems at a high temporal and spatial resolution. A comparison of ATP data with related variables, such as particulate carbon, nitrogen, chlorophyll, and turbidity in pelagic samples, yielded significant and strong correlations in a gradient from the tributaries of the Chesapeake Bay (sigma-t = 8) to the open North Atlantic (sigma-t = 29). Correlations varied between ATP and biomass depending on the microscopic method employed. Despite the much greater effort involved, biomass determined by microscopy correlated poorly with other …


Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia Dec 2023

Reducing Food Scarcity: The Benefits Of Urban Farming, S.A. Claudell, Emilio Mejia

Journal of Nonprofit Innovation

Urban farming can enhance the lives of communities and help reduce food scarcity. This paper presents a conceptual prototype of an efficient urban farming community that can be scaled for a single apartment building or an entire community across all global geoeconomics regions, including densely populated cities and rural, developing towns and communities. When deployed in coordination with smart crop choices, local farm support, and efficient transportation then the result isn’t just sustainability, but also increasing fresh produce accessibility, optimizing nutritional value, eliminating the use of ‘forever chemicals’, reducing transportation costs, and fostering global environmental benefits.

Imagine Doris, who is …


Protocol For An Agent-Based Model Of Recombination In Bacteria Playing A Public Goods Game, Isaiah Paolo A. Lee, Omar T. Eldakar, J. Peter Gogarten, Cheryl P. Andam Dec 2023

Protocol For An Agent-Based Model Of Recombination In Bacteria Playing A Public Goods Game, Isaiah Paolo A. Lee, Omar T. Eldakar, J. Peter Gogarten, Cheryl P. Andam

Biology Faculty Articles

Agent-based models are composed of individual agents coded for traits, such as cooperation and cheating, that interact in a virtual world based on defined rules. Here, we describe the use of an agent-based model of homologous recombination in bacteria playing a public goods game. We describe steps for software installation, setting model parameters, running and testing models, and visualization and statistical analysis. This protocol is useful in analyses of horizontal gene transfer, bacterial sociobiology, and game theory.

For complete details on the use and execution of this protocol, please refer to Lee et al.1


Assessing The Role Of The Microbiome, Parasite Infections, And Movement In Avian Health, Olivia N. Choi Dec 2023

Assessing The Role Of The Microbiome, Parasite Infections, And Movement In Avian Health, Olivia N. Choi

Electronic Theses and Dissertations

Avian health encompasses the physical, physiological, and behavioral well-being of birds. Assessing avian health is not only important for the conservation and management of wild birds and the recreational economy, but also for the management of infectious diseases that threaten public health and agriculture. Birds, comprising approximately 10,000 species and an estimated 50 billion individuals worldwide, are known to be involved in the spread of pathogens, some of which are zoonotic (from animals to humans), such as avian influenza and West Nile viruses. Individual measures of avian health may include physical measurements (e.g., body mass, wing length), pathogen infection status, …


Breaking Virulent: The Coincidental Evolution Of Virulence Factors In Bacteria., Rhiannon Emmanuelle Cecil Dec 2023

Breaking Virulent: The Coincidental Evolution Of Virulence Factors In Bacteria., Rhiannon Emmanuelle Cecil

Electronic Theses and Dissertations

Understanding how innocuous organisms can evolve to be pathogenic to humans is of increasing global concern. Further, understanding how existing pathogens may evolved to be more virulent is also vital to our ability to provide healthcare to people afflicted with diseases that promote chronic bacterial infections, such as cystic fibrosis. With the rise of antibiotic resistance in both bacteria and fungi it is paramount that new therapeutics are identified. Understanding what mutations occur that result in increased virulence in microbes can potentially provide new targets for antimicrobial drugs to combat antibiotic resistance. The Coincidental Evolution Hypothesis is a fundamental hypothesis …


The Discovery Of A Novel Bacteria From A Large Co-Assembly Of Metagenomes, Matthew Finkelberg Nov 2023

The Discovery Of A Novel Bacteria From A Large Co-Assembly Of Metagenomes, Matthew Finkelberg

Masters Theses

In the summer of 2022, a co-assembly of metagenome was created using the microbes found at Barres Woods in Harvard Forest. 14 samples were taken, and sample was split into the organic and mineral layer, which totals 28 Bulk MAGs. Within this Co-assembly, 4 different genomes were found which were designated with the phylum of FCPU426. Three of which were considered medium quality and one being assigned high quality. The novel phyla first appeared in NCBI and GTDB databases in June 2018. The name FCPU426 dates to 2010 and was named based on the 16s amplicon sequencing.

The novel phylum …


Distinguishing Community Assembly Through Functional Redundancy Models., Sandra A. Tsiorintsoa, Sharon Bewick, Matthew Macauley Nov 2023

Distinguishing Community Assembly Through Functional Redundancy Models., Sandra A. Tsiorintsoa, Sharon Bewick, Matthew Macauley

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


Connecting The Nebraska Water Quality Index To The Aquatic Microbial Community Of The North Platte River Basin, Nebraska, Paula R. Guastello Nov 2023

Connecting The Nebraska Water Quality Index To The Aquatic Microbial Community Of The North Platte River Basin, Nebraska, Paula R. Guastello

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

The Nebraska Water Quality Index, under development by the Nebraska Department of Environment and Energy, summarizes in a single value eight environmental parameters that have been monitored in Nebraska for nearly 20 years. Water quality parameters including those used in the Nebraska Water Quality Index have been shown in previous studies to impact bacterial growth. As such, this index has the potential to correlate with the freshwater microbial community. Here, I relate the Nebraska Water Quality Index to microbial community composition and structure using 16S rRNA gene amplicon sequence data collected from the North Platte River Basin, Nebraska. This index …


Tracing Evolution Of Gene Transfer Agents Using Comparative Genomics, Roman Kogay Nov 2023

Tracing Evolution Of Gene Transfer Agents Using Comparative Genomics, Roman Kogay

Dartmouth College Ph.D Dissertations

The accumulating evidence suggest that viruses and their components can be domesticated by their hosts, equipping them with convenient molecular toolkits for various functions. One of such domesticated system is Gene Transfer Agents (GTAs) that are produced by some bacteria and archaea. GTAs morphologically resemble small phage-like particles and contain random fragments of their host genome. They are produced only by a small fraction of the microbial population and are released through a lysis of the host cell. Bioinformatic analyses suggest that GTAs are especially abundant in the taxonomic class of Alphaproteobacteria, where they are vertically inherited and evolve …


Evolution Of Overlapping Reading Frames In Virus Genomes, Laura Muñoz Baena Aug 2023

Evolution Of Overlapping Reading Frames In Virus Genomes, Laura Muñoz Baena

Electronic Thesis and Dissertation Repository

Viruses are formidable pathogens that represent the majority of biological entities in our planet, and their genomes are a source of interesting enigmas. One feature in which virus genomes are usually rich, is the presence of overlapping reading frames (OvRFs) — portions of the genome where the same nucleotide sequence encodes more than one protein. OvRFs are hypothesized to be used by viruses to encode proteins more compactly and to regulate transcription. In addition, OvRFs might be a source of gene novelty, facilitating the creation of new open reading frames (ORF) within the transcriptional context of existing ones.

To characterize …


Characterization Of Antimicrobial Properties Of Excrement And Functional Microbiome Of Black Vultures (Coragyps Atratus), Bridgette Gray Jul 2023

Characterization Of Antimicrobial Properties Of Excrement And Functional Microbiome Of Black Vultures (Coragyps Atratus), Bridgette Gray

Theses

Black vultures, Coragyps atratus, are obligate scavenging birds that consume and dispose of decaying carcasses and carrion. They fulfill a key ecological niche in the environments in which they live. It has been observed that these vultures sometimes excrete bodily waste onto their legs. This adaptive behavior could help aid them in controlling bacteria and other microbes they encounter while stepping into a carcass to eat. This study directly examined the antimicrobial properties of the excrement of black vultures across various bacterial species utilizing a zone of inhibition test and a nematode species utilizing a survival assay. The black vulture …


Sympatric Soil Microbe Interactions Between Streptomyces And Fusarium Isolates, Lehren A. Olk-Szost Jul 2023

Sympatric Soil Microbe Interactions Between Streptomyces And Fusarium Isolates, Lehren A. Olk-Szost

All NMU Master's Theses

Interkingdom interactions between soil bacteria and fungi may play a critical role in occurrence of disease suppressive soils, yet our understanding of these interactions remains limited. Streptomyces are well-known producers of antimicrobial compounds important to medicine and agriculture. Production of these secondary metabolites is often mediated by quorum sensing. Most Streptomyces research occurs in single species experiments, yet new metabolites have been discovered in interspecies co-culture experiments. Interspecies, intergenic, and interkingdom co-culture research will likely reveal many valuable compounds, and strengthen our understanding of complex ecological interactions in soil microbiomes. Interactions between sympatric Streptomyces and Fusarium isolates from disease suppressive …


Considerations For The Use Of Mycorrhizal Fungi Inoculants In Coal Mine Reclamation And Reforestation In Appalachia: A Guide Of Best Practices And Management Recommendations, Cole Hansen Reistrup May 2023

Considerations For The Use Of Mycorrhizal Fungi Inoculants In Coal Mine Reclamation And Reforestation In Appalachia: A Guide Of Best Practices And Management Recommendations, Cole Hansen Reistrup

Master's Projects and Capstones

Nearly all terrestrial plants form symbiotic relationships with mycorrhizal fungi. These beneficial soil microbes support plant health by increasing plants’ access to nutrients and water, protecting them from pathogens, improving soil properties, and more. A challenge to restoring forests on coal mined land in Appalachia is that mine soils are often degraded in a number of ways, including lacking mycorrhizal fungi, which makes mine soils difficult for trees to grow upon. Substantial improvements to coal mine reforestation success have been made since the development of the Forestry Reclamation Approach in 2005 that provides guidelines for how to create a suitable …


Eco-Interoception: What Plants, Fungi And Protista Have Taught My Body, Sara Riley Dotterer May 2023

Eco-Interoception: What Plants, Fungi And Protista Have Taught My Body, Sara Riley Dotterer

Art Theses and Dissertations

To me, ecology is the relational, full-body awareness that I am made up of and deeply connected to everything around me; and for better or worse, this is reciprocal. I form ecotones, an ecological transitional zone between two ecosystems, with the world around me. I use this ecotonal lens to blur binaries and dissolve boundaries between me and the world “outside my body.” During my Masters of Fine Arts at Southern Methodist University, I have continuously explored and represented the lives of various more-than-human species outside of my body, including plants, fungi and protista through an ecotonal lens. Although these …


Mechanistic Examination Of Protist-Mediated Plant Growth Through The Comparative Development Of Medicago Truncatula, Shane Connolly May 2023

Mechanistic Examination Of Protist-Mediated Plant Growth Through The Comparative Development Of Medicago Truncatula, Shane Connolly

University Scholar Projects

Protists are known to increase plant growth through two main mechanisms: the microbial loop and the alteration of the root microbiome. The microbial loop is a nutrient recycling method in which protists provide inorganic nitrogen ions to the plant. Alteration of root microbiome leads to the removal of plant pathogens and shifting communities towards plant growth-promoting bacteria (PGPB). This study aimed to elicit which mechanism could produce the largest boost in shoot weight for Medicago truncatula. A series of microcosm experiments were explored in which M. truncatula was grown with variable microbiome structures to allow for mechanism differentiation. The …


Causes And Consequences Of Lasr Mutant Selection In Pseudomonas Aeruginosa Populations, Dallas L. Mould May 2023

Causes And Consequences Of Lasr Mutant Selection In Pseudomonas Aeruginosa Populations, Dallas L. Mould

Dartmouth College Ph.D Dissertations

Change is the only constant in life, and these changes, though random in nature, can have consequences. Quorum sensing is heterogeneous in phenotype and prone to negative selection. In P. aeruginosa, the regulator LasR is frequently non-functional in phylogenetically diverse isolates. Through repeated experimental evolution and mathematical modeling, we show that differences in growth enable lasR mutant evolutionary success and this requires a system enabling metabolic choices, known as carbon catabolite repression (or catabolite repression). The differences in catabolite repression between wild type and lasR mutants enable altered metabolite preferences, and the resulting differences in metabolic states enable intraspecies …


The Response Of Microcystis And The Microbiome To Exogenous Hydrogen Peroxide, Bryan A. Puma May 2023

The Response Of Microcystis And The Microbiome To Exogenous Hydrogen Peroxide, Bryan A. Puma

Masters Theses, 2020-current

Microcystis spp. produce prolific annual blooms in freshwater systems worldwide. The success of these blooms depends heavily on the Microcystis spp. overcoming environmental factors such as oxidative stress caused by reactive oxygen species (ROS) like hydrogen peroxide. Most Microcystis genomes do not contain many genes for responding to oxidative stress, including those that encode the enzyme catalase. Other cyanobacteria such as Prochlorococcus that also lack hydrogen peroxide degrading enzymes have been shown to benefit from partnerships with heterotrophic bacteria. Microcystis spp. may also receive similar benefits from heterotrophic bacteria in the phycosphere. To test this hypothesis, we examined the …


Impacts Of Bacterial Evolution On Host Lethality In Drosophila, Andrew Preston May 2023

Impacts Of Bacterial Evolution On Host Lethality In Drosophila, Andrew Preston

College of Arts & Sciences Senior Honors Theses

Evolution is the process by which species change their genetic traits, such as the pathogenicity of bacteria, over time in response to changes in their environment. Although the genetic mechanisms underlying many evolutionary processes have been revealed, it is still not well understood how opportunistic pathogens, such as Pseudomonas aeruginosa, become virulent. The overall goal of this thesis is to test the Coincidental Evolution Hypothesis, which proposes that the virulence of opportunistic pathogens evolves coincidentally as a by-product of their interaction with their natural predators. I hypothesized that the virulence of ancestral Pseudomonas aeruginosa changes over time if it co-evolves …


An Ecological Perspective Of American Rodent-Borne Orthohantavirus Surveillance, Nathaniel Mull May 2023

An Ecological Perspective Of American Rodent-Borne Orthohantavirus Surveillance, Nathaniel Mull

Graduate Theses and Dissertations

Orthohantaviruses are a global group of viruses found primarily in rodents, though several viruses have also been found in shrews and moles. Many rodent-borne orthohantaviruses are capable of causing one of several diseases in humans, and the mortality associated with these diseases ranges from < 0.1% - 50% depending on the specific etiological virus. In North and South America, orthohantavirus research was ignited by an outbreak of severe disease in the Four Corners region of the United States in 1993. However, despite the discovery of over 20 orthohantaviruses in the Americas, our understanding of orthohantavirus ecology and virus-host dynamics in this region is still limited, and orthohantavirus surveillance is generally restricted in scope to select regions and small portions of host distributional ranges. In Chapter I, I present a literature review on the current understanding of American rodent-borne orthohantavirus ecology. This review focused on under-studied orthohantaviruses, addressing gaps in knowledge by extrapolating information from well-studied orthohantaviruses, general rodent ecology, and occassionally from Eurasian orthohantavirus-host ecology. There were several key conclusions generated from this review that warrant further research: 1) the large number of putative orthohantaviruses and gaps in orthohantavirus evolution necessitate further surveillance and characterization, 2) orthohantavirus traits differ and are more generalizable based on host taxonomy rather than geography, and 3) orthohantavirus host species are disproportionately found in grasslands and disturbed habitats. In Chapter II, I present a prioritized list of rodent species to target for orthohantavirus surveillance based on predictive modeling using machine learning. Probable orthohantavirus hosts were predicted based on traits of known orthohantavirus hosts using two different types of evidence: RT-PCR and virus isolation. Predicted host distributions were also mapped to identify geographic hotspots to spatially guide future surveillance efforts. In Chapter III, I present a framework for understanding and predicting orthohantavirus traits based on reservoir host phylogeny, as opposed to the traditional geographic dichotomy used to group orthohantaviruses. This framework establishes three distinct orthohantavirus groups: murid-borne orthohantaviruses, arvicoline-borne orthohantaviruses, and non-arvicoline cricetid-borne orthohantaviruses, which differ in several key traits, including the human disease they cause, transmission routes, and virus-host fidelity. In Chapter IV, I compare rodent communities and orthohantavirus prevalence among grassland management regimes. Sites that were periodically burned had high rodent diversity and a high proportion of grassland species. However, rodent seroprevalence for orthohantavirus was also highest in burned sites, representing a trade-off in habitat management outcomes. The high seroprevalence in burned sites is likely due to the robust populations supported by the high quality habitat resulting from prescribed burning. In Chapters V and VI, I describe Ozark virus and Sager Creek virus, two novel orthohantaviruses discovered from specimens collected during Chapter IV. Both chapters report full genome sequences of the respective viruses and compare both nucleotide and protein phylogenies with related orthohantaviruses. Additionally in Chapter VI, I support the genetic analyses with molecular and ecological characterizations, including seasonal fluctuations in host abundance, correlates of prevalence, evidence of virus shedding, and information on host cell susceptibility to Sager Creek virus.


Effect Of Temperature On The Microbiome Of A Laboratory Reared Colony Of Haemaphysalis Longicornis Ticks, Brianna Mitchell May 2023

Effect Of Temperature On The Microbiome Of A Laboratory Reared Colony Of Haemaphysalis Longicornis Ticks, Brianna Mitchell

Poster Presentations

Honors research poster.

Haemaphysalis longicornis is a species of tick native to eastern Asia, including eastern China, Japan, eastern Russia, and Korea. To date, it has invaded and has now established its existence in Australia, New Zealand, and several of the Pacific Islands. This species of tick has recently been introduced to the United States, having a confirmed sighting in November 2017 on a sheep farm in New Jersey and since establishing populations in 18 states along the east coast and Appalachia. Based on the existing locations of H. longicornis in its native regions, as well as in the United …


Effect Of Temperature On The Microbiome Of A Laboratory-Reared Colony Of Haemaphysalis Longicornis Ticks, Brianna L. Mitchell May 2023

Effect Of Temperature On The Microbiome Of A Laboratory-Reared Colony Of Haemaphysalis Longicornis Ticks, Brianna L. Mitchell

Honors Theses

Haemaphysalis longicornis ticks are invasive to the United States with potential to transmit several tick-borne pathogens that are native to the United States. Based on existing locations of H. longicornis in its native regions in Asia, as well as its invasive populations that are established in the United States, several geographic range prediction models have been produced to help understand future range expansion and distribution of this invasive tick in North America. Unfortunately, these models do not all agree and there is uncertainty associated with the potential geographic range expansion of H. longicornis ticks in North America. Climate can affect …


Long‑Term Adaptation To Galactose As A Sole Carbon Source Selects For Mutations Outside The Canonical Gal Pathway, Artemiza A. Martínez, Andrew Conboy, Sean Buskirk, Daniel A. Marad, Gregory I. Lang Feb 2023

Long‑Term Adaptation To Galactose As A Sole Carbon Source Selects For Mutations Outside The Canonical Gal Pathway, Artemiza A. Martínez, Andrew Conboy, Sean Buskirk, Daniel A. Marad, Gregory I. Lang

Biology Faculty Publications

Galactose is a secondary fermentable sugar that requires specific regulatory and structural genes for its assimilation, which are under catabolite repression by glucose. When glucose is absent, the catabolic repression is attenuated, and the structural GAL genes are fully activated. In Saccharomyces cerevisiae, the GAL pathway is under selection in environments where galactose is present. However, it is unclear the adaptive strategies in response to long-term propagation in galactose as a sole carbon source in laboratory evolution experiments. Here, we performed a 4,000-generation evolution experiment using 48 diploid Saccharomyces cerevisiae populations to study adaptation in galactose. We show that fitness …


From Micro To Macro: Examining Potential Microbiome Mediated Influences On Human Growth And Health Outcomes Through Breastfeeding And Antibiotic Exposures, Nicole K. Phillips Jan 2023

From Micro To Macro: Examining Potential Microbiome Mediated Influences On Human Growth And Health Outcomes Through Breastfeeding And Antibiotic Exposures, Nicole K. Phillips

Electronic Thesis and Dissertation Repository

Human microbiome research has rapidly developed over the past two decades yet absent from most research is the composition and dynamics of microbiomes within human populations. Given the limitations in longitudinal studies which requires decades of repeated microbe taxonomic testing of a population sample, an alternative option is to examine microbiomes and their influences via proxies using pre-existing health datasets. This research demonstrates preliminary associations between presumed disrupted and supportive microbiomes dynamics proxied by antibiotic and breastmilk exposure respectively. Using health record data across the life span from approximately 500,000 U.K. participants, this research demonstrates variable altered growth and health …


Comparison Of Groundwater Chemistry And Associated Biodiversity Of Sulfidic Karst Habitats In Southcentral Kentucky, Kendall Wheeler Jan 2023

Comparison Of Groundwater Chemistry And Associated Biodiversity Of Sulfidic Karst Habitats In Southcentral Kentucky, Kendall Wheeler

Mahurin Honors College Capstone Experience/Thesis Projects

In most ecosystems, primary production is conducted by plants or photosynthetic microbes; however, extremophilic sulfur-oxidizing bacteria can use hydrogen sulfide gas (H2S) as an electron donor to produce metabolic energy in a type of metabolism called chemoautotrophy. These ecosystems are a prominent feature of some karst landscapes, and two have been observed in the Mammoth Cave system, Sulphur River in Parker Cave and Marianne’s Pass in Mammoth Cave National Park respectively.

Sulfidic water is ubiquitous in southcentral Kentucky and is strongly associated with hydrocarbon deposits. This oil boom of the 1880s in this region predates most environmental regulation and records …


Under Ice Photosynthetic Primary Production And Dark Carbon Fixation In A Temperate Freshwater System, Vanessa Cubillos Tellez Jan 2023

Under Ice Photosynthetic Primary Production And Dark Carbon Fixation In A Temperate Freshwater System, Vanessa Cubillos Tellez

Dissertations, Master's Theses and Master's Reports

Ice-covered lakes are vulnerable to environmental change, especially those in the Northern Hemisphere where ice cover is rapidly declining due to global warming. These changes can alter metabolic processes and disrupt carbon cycling driven by primary producers who form the base of the food chain and are key to sustaining ecosystem function. Photosynthetic primary production and dark carbon fixation under the ice in the Keweenaw Waterway, a temperate freshwater system that is ice-covered for ~3 months out of the year, were studied using a carbon isotopic labeling (14C-bicarbonate) technique. Water samples were collected weekly during ice cover and monthly during …


Soil And Compost Tea: A New Restoration Technique?, Carol E. Day Jan 2023

Soil And Compost Tea: A New Restoration Technique?, Carol E. Day

Master's Theses and Doctoral Dissertations

Historically, prairie restorations have lacked the plant diversity seen in remnant prairies. Most restoration practices focus on reestablishing the plant community but overlook the soil microbial community even though microbes are critical to habitat functioning. Developing techniques that increase soil microbes in prairie restorations is critical to ensuring diverse restored habitats. We compared how microbial communities differed between remnant and restored prairie sites. We also investigated if soil and compost teas could be used to reintroduce microbes to restored prairie soil and if the teas affected native plant establishment. We found significant differences in the levels of bacterial taxa between …


Microbial Communities In The Guana Tolomato Matanzas National Estuarine Research Reserve: An Assessment Of The Responses Of Spartina Alterniflora Epiphytes To Nitrogen Enrichment, And A Characterization Of Benthic Cyanobacterial Diversity, Anne C. Hurley Jan 2023

Microbial Communities In The Guana Tolomato Matanzas National Estuarine Research Reserve: An Assessment Of The Responses Of Spartina Alterniflora Epiphytes To Nitrogen Enrichment, And A Characterization Of Benthic Cyanobacterial Diversity, Anne C. Hurley

UNF Graduate Theses and Dissertations

Elevated nitrogen and phosphorus inputs from anthropogenic sources, which can lead to significant increases in algal biomass and changes in algal community composition, poses a serious threat to estuarine ecosystems worldwide. While numerous studies have addressed the impacts of nutrient enrichment on epiphytic algae in seagrass habitats, few have investigated potential nutrient-driven changes to epiphytes on emergent salt marsh plants, such as Spartina alterniflora. Epiphytic microalgae on S. alterniflora play an important role in food availability in salt marsh ecosystems, and epiphytic nitrogen-fixing cyanobacteria also provide an important source of nitrogen for salt marsh consumers. The first study included …