Environmental Microbiology and Microbial Ecology Commons^™

Enhancing Urban Garden Capacity By Linking Biodiversity And Ecosystem Function, Mary T. Nguyen, Carleen Rauh, Shelby Gresch, Charlotte Correiro, Heidi Elmendorf, Adriane Fugh-Berman, Gina Wimp, Alexandra L. Decandia

Virginia Journal of Science

Urban agriculture broadly describes food and plant cultivation in metropolitan areas. While biodiversity is thought to support ecosystem health and resilience, the relationship between above-ground and below-ground diversity has been understudied in urban green spaces. This study examines plant, animal, bacterial, and fungal diversity across three distinct urban habitats: a turf lawn, a forb garden, and a farming space. Using bacterial 16S rRNA and fungal ITS2 sequencing, soil nutrient analyses, and surveys of vegetation and wildlife, we connect diverse philosophies in urban agriculture to their role in advancing community diversity and ecosystem function. We found that different urban gardens support …

Methane Consumption Rates By Coastal Virginia Beach Microbes, James R. Bailey Ii

Knowledge and Creativity Expo

This study measures whether microbial communities in the shallow coastal waters of Virginia Beach are capable of consuming methane in the water column. Using methane enrichment incubations and gas chromatography, we found no measurable methane oxidation of our samples over multi-day periods. These results suggest that these coastal waters may act as net sources of atmospheric methane.

Microbial Community Structure In Global Soils, Matthew Jabro

CMC Senior Theses

Soil harbors the most diverse microbial communities on Earth, yet whether predictable community types exist across biomes and whether taxonomic composition encodes habitat of origin remain open questions at global scale. This thesis addresses both questions by applying unsupervised clustering and supervised classification to transformed 16S ribosomal RNA (rRNA) amplicon profiles from two independent datasets: the global topsoil survey of Bahram et al. (193 samples) and the Earth Microbiome Project (EMP) soil subset of Thompson et al. (2,209 samples). Application of a sample clustering method based on a mixture of Gaussian Graphical Models (MixGGM) identified 19 clusters in the topsoil …

Pipeline Corrosion And Relevant Microbial Influence, Renee E. Bamberger

Williams Honors College, Honors Research Projects

This study investigated the role of microbial activity and oxygen availability in the corrosion of carbon steel pipelines with a focus on microbially influenced corrosion (MIC). Sediment collected from Old Woman Creek, Ohio, was used to simulate natural soil conditions, and carbon steel coupons were incubated under four treatments: nonsterile oxic, nonsterile anoxic, autoclaved oxic, and autoclaved anoxic over 85 days. Corrosion was assessed through mass loss measurements and the analysis of pH, sulfate, chloride, and dissolved iron concentrations. The greatest mass loss was observed in autoclaved oxic conditions, contrary to the initial hypothesis that microbial activity would greatly enhance …

Environmental Monitoring In Shallow Lakes: Public Health Threats In Urban Waters, Kyleigh E. Johnson

Theses and Dissertations

Lakes are an integral part of urban and suburban communities, providing ecological, recreational, and public health benefits. Many of these lakes are located in densely populated areas and are subject to urban influences on water quality. Algal toxins and Escherichia coli are two common recreational concerns. Algal toxins come from harmful algal blooms that are influenced by nutrient availability and temperature, while bacteria are often introduced through run-off and animal waste. Sampling every 3-4 weeks from May-October 2025 allowed for the assessment of seasonal patterns and site-specific differences across nine lakes in the Richmond area. The highest bacterial concentrations appeared …

Remediation Impacts Metal Concentrations And Metal Tolerant Bacteria In Soils Of The Missouri Tri-State Mining District, Ophelia R. Pettington

Graduate Theses/Dissertations

After over 100 years of Zn and Pb mining in the Tri-State mining district (TSMD), former mines continue to be sources of metals. Metal contaminated soils can be remediated using plant-microbe interactions. Plants manipulate their microbiome and recruit microbes to increase metal tolerance. Remediating bacteria are site-specific and identifying native microbes can accelerate remediation efforts. Studies relating microbes and metal concentrations in remediated areas in the TSMD are scarce. I collected root and bulk zone soils associated with Andropogon virginicus from remediated and non-remediated sites in Webb City, MO. I used 16S rRNA gene amplicon sequencing to evaluate the bacterial …

Mathematically Modeling Stoichiometric Drivers Of Heterotrophic N2 Fixation, Corday R. Selden, Rebecca Everett, Halvor H. Halvorson, Megan E. Berberich, Luca Schenone, Angela Peace, Renn Schipper, Edwin Cruz-Rivera, James Powell, Keisuke Inomura, Robinson W. Fulweiler, Amy M. Marcarelli, J Thad Scott

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.

Elucidating The Relationship Between Water Quality And Antibiotic Resistance Of Rainwater Microbes Across Western Humboldt County, Theo P. Murphy, Eve Wendley, Justice Laskowski, Tyler Paredes

Humboldt Journal of Microbiology

Limited studies have been conducted regarding the fecal contamination and microbial dispersal through rainwater, with no known studies investigating the potential connection between antibiotic resistant microbes and water quality in rainwater. This study seeks to identify the presence of a correlation between water quality and incidence of antibiotic resistance in rainwater microbes. We hypothesize that there will be a correlation between these two variables. We additionally anticipate a high incidence of fecal contamination across rural and urban collection sites alike, with fecal contamination being more prevalent in rural areas than urban locals. To determine water quality, we measured the concentration …

The Effects Of Plastic Mulch And Irrigation On Hemp Chemistry And Leaf Endophytes, Allison Rietman, Connor Morozumi, Robert C. Pearce, Natalie Christian

Journal of Agricultural Hemp Research

As an emerging crop, cultivation techniques for industrial hemp (Cannabis sativa L.) are still being developed and optimized. For example, irrigation and plastic mulching are some management practices that have been touted for their benefits in improving crop quality. Both techniques ensure ample water availability, which has often been attributed to improving hemp cannabinoid and terpene composition. In this study, we examined how supplemental irrigation implemented in a plastic mulch system influenced the cannabinoid and terpene profiles of one cultivar of CBD hemp, Lifter. We grew industrial hemp in field with plastic mulch and applied regular irrigation to one group …

The Astrobiological Figure Of Humboldt As Pioneer In The Rock Varnish Research, Jose Jordan-Soria

Homage to Alexander von Humboldt: Travels to and from Spain Throughout the Centuries / Homenaje a Alexander von Humboldt: Viajes hacia y desde España de todos los siglos

From Humboldt is particularly interesting -and little know- his description of mineral coatings on rocks 200 years ago, reported in his book Personal Narrative of Travels to the Equinoctial Regions of the New Continent during the years 1799-1804, co-written with Aimé Bonpland, for which is considerate the father of rock coating research. On June 5th 1799 set sail from A Coruña -Spain- to Cumaná -Venezuela- beginning five years of expedition. While they explored the Orinoco River system, in th eriver basin waterfalls, Humboldt observed the presence of dark coating depositions. He ascertained a manganese-rich accretion, reporting similar structures in other …

Colonization-Persistence Trade-Offs In The Human Microbiome, Liam F. Nokes

Environmental Studies Senior Theses

Understanding how diverse microbial taxa coexist in the human body without competitively excluding one another remains a key challenge in microbiome ecology. One proposed explanation is the colonization-persistence trade-off, where species with high colonization ability are poor persisters, and vice versa. We test for this trade-off across human associated microbial communities among many individuals and in multiple body sites using a large-scale participant-level meta-analysis of longitudinal microbiome datasets curated from the MGnify database. We applied island biogeography-based models to calculate effective colonization and persistence rates for microbial families and genera across 606 individuals over twenty-six studies. Regression of the log-transformed …

Toxicity And Biodegradability Of Novel Boronium Vs Conventional Ammonium-Based Antimicrobial Compounds In Wastewater Treatment Systems, Noor Shalan

Honors Theses

Quaternary ammonium compounds (QACs) are highly effective as disinfectants, herbicides, and pesticides; thus, overuse causes elevated levels of residual toxicity in domestic and industrial wastewater. QACs can be toxic to essential bacteria breaking down pollutants in wastewater treatment plants (WWTPs) and can remain untreated in effluent, harming the environment, and contributing to antibiotic resistance, posing risks to human health. Novel boronium-based antimicrobial compounds have demonstrated efficacy in eliminating bacteria, fungi, and viruses. If the boronium compounds exhibit lower residual toxicity, they could offer a promising alternative to QACs. Because these compounds are still in development, their potential toxicity to the …

Impact Of Shear Flow On Marine Biofilms Using Hyperspectral Imaging, Shantanu Mahesh Kore

All Theses

Various microbial communities in marine biofilms cause biofouling on submerged surfaces, posing challenges to marine industries. Despite their ecological and economic importance, biofilms' biomechanical and biochemical responses to hydrodynamic shear stress are insufficiently understood, particularly in dynamic flow conditions. To fill this gap, our study uses an innovative fiber-optic hyperspectral imaging (HSI) system and a supercontinuum laser source to examine marine biofilms' structure, composition, and detachment behavior at different shear stress levels.

To detect spectral and spatial heterogeneity in live biofilms without labeling, we created a custom imaging pipeline that captures reflectance spectra in the 600-850 nm range, targeting microbial …

Investigating Drivers In Phytoplankton Between Lentic And Lotic Ecosystems Within Twelvepole Creek Watershed, Devin Lee Farmer

Theses, Dissertations and Capstones

Harmful Algal Blooms (HABs) threaten aquatic ecosystems, local economies, and water quality. While extensively studied in lakes (lentic systems), their impact on flowing waters (lotic systems) remains underexplored. This study examined algal drivers in both ecosystems within the same watershed, focusing on Beech Fork Lake (lentic) and Twelve Pole Creek (lotic). Key environmental factors, including pH, turbidity, dissolved oxygen, and nutrient levels, were measured using in situ sensors and laboratory analysis. Water samples were analyzed for nitrogen, phosphorus, and algal biomass for comparison to environmental conditions. Phytoplankton was preserved for identification in future research. By comparing these environments, this study …

Impact Of Submarine Groundwater Discharge On Microbial Communities In A Highly Anthropized Coastal Lagoon (Mar Menor, Se Spain), Daniel Romano-Gude, Júlia Dordal-Soriano, Júlia Rodriguez-Puig, Andrea G. Bravo, Irene Alorda-Montiel, Aaron Alorda-Kleinglass, Marc Diego-Feliu, Cristina Romera-Castillo, Rebeca Mallenco-Fornies, Javier Gilabert, Jordi Garcia-Orellana, Valentí Rodellas, Clara Ruiz-González

OES Faculty Publications

Submarine groundwater discharge (SGD) supplies large quantities of nutrients and other terrestrial elements to coastal ecosystems, impacting marine biota and ecosystem functioning. Despite the relevance of prokaryotes for marine biogeochemistry, little is known about their responses to groundwater inputs. Here we explored the impact of SGD on the spatiotemporal patterns of prokaryotic communities from the Mar Menor (Murcia, Spain), a highly anthropized hypersaline coastal lagoon that receives large amounts of nutrient-polluted SGD. Using 16S rRNA amplicon sequencing, activity assays, and flow cytometry, we investigated the dynamics of prokaryotic communities across the lagoon and its connected environments (freshwater streams, groundwater, soils, …

Using Bivalves As An Indicator For Fecal Bacteria, Kamala Chuss

Honors Scholar Theses

This project focuses on the integration of fecal bacteria from warm-blooded animals into bivalve tissue, and the utilization of bivalves as an indicator for fecal bacteria in waterways. Bivalves may give a more representative long-term average of fecal bacteria in water as compared to direct water testing. The primary objective is to create a standard operating procedure to use bacterial testing of bivalves as a proxy for bacteria concentration in the water. This method can be used in places where bivalves do not already exist by adding them to a body of water, or by collecting bivalves that already exist …

The Relationship Between Salvinia Molesta Infestation And The Microbial Ecology Of Wetlands At Caddo Lake, Tx, Usa, Martin Hadsell

Electronic Theses and Dissertations

Wetlands are known to host many beneficial geochemical processes such as nutrient cycling and carbon sequestration. These processes are primarily driven by the microbial communities within a wetland. The establishment of non-native invasive species within wetlands has the potential to alter the once beneficial functionality of wetland microbial communities due to the sensitivity microbes have towards environmental changes. Because of this, several metagenomic studies have been conducted to assess microbial community response to aquatic plant invasion; however, there haven’t been any studies researching the influence of Salvinia molesta (D.S. Mitch.), commonly known as Giant Salvinia, on microbial communities. The goal …

Boosting The Power Performance Of Microbial Fuel Cells By Using Dual Nanomaterial-Modified Carbon Felt Electrodes, Krishna Thapa, Wenyan Liu, Yuwei Zhang, David J. Westenberg, Yishu Zhou, Risheng Wang

Chemistry Faculty Research & Creative Works

Innovative design enhancements to microbial fuel cells (MFCs) are pivotal for improving their viability as renewable energy sources. This study introduces a dual approach to electrode modification, integrating polyaniline (PANI) and gold nanoparticles (AuNPs) on carbon felt (CF) anodes coupled with a unique cathode composed of DNA origami and chitosan. The synergistic effect of PANI and AuNPs significantly increases the hydrophilicity and conductivity of the anode, leading to a considerable surge in power density. Concurrently, the biocompatible DNA origami and chitosan-functionalized cathode facilitates efficient electron transfer without relying on conventional catalysts. Together, these modifications yield a 52.42% increase in the …

Effects Of Microplastic Biofilms On An Anthropogenically Impacted Suburban Lake, Paris M. Velasquez

Masters Theses

Plastics have been observed in every location on the planet, and their prevalence in the environment is due in part to their strong resistance to degradation. Inland lakes are susceptible to plastic pollution by highway runoff, which contains plastic fragments of brake pads, car tires, litter, and road paint. These plastics eventually enter freshwater environments and degrade into microplastics (

The Environment Of Glaciovolcanic Caves And Their Value As Planetary Analogues, Christian Stenner, Lee J. Florea, Linda Sobolewski, Andreas Pflitsch, Morgan Cable, Roberto Anitori, Richard E. Davis, Kathleen Graham, Glyn Williams-Jones

FRONTIERS UNBOUND: Exploring Extreme Environments

No abstract provided.

The Ecology Of Chemosynthesis In Submerged Coastal Caves, Robert Scharping, Michael Casso, Isabel Schaal, Paul Henderson, James Garey, Matthew Charette, John Pohlman, Stefan Sievert

FRONTIERS UNBOUND: Exploring Extreme Environments

No abstract provided.

The Ecosystem Of A Remarkable Glaciovolcanic Cave At Mount Meager, British Columbia, Canada, Christian Stenner, Kathleen Graham, Morgan Cable, Glyn Williams-Jones, Jared J. Clance, Jacob Shaffer, Jill Mikucki, Anna Szynkiewicz, Olivia Vinnes, Michael Paton, Jeremy Nash

FRONTIERS UNBOUND: Exploring Extreme Environments

No abstract provided.

Time-Transgressive Microbial Diversity In A Tropical Bat Guano Accumulation, Deer Cave, Mulu, Borneo, Joyce Lundberg, Donald A. Mcfarlane

International Journal of Speleology

Bat guano accumulations in caves can constitute large deposits of organic material, particularly chitin and its degradation products, that host a diverse microbiome. Previous microbiological studies have not addressed the stratified nature of these deposits in the context of the timeframe of the decomposition process. We present such data (temperature, pH, DNA sampling of eight carbon-dated strata) for a 75 cm-deep tropical guano accumulation that undergoes complete decomposition over a timescale of ~120 years. The aerobic, surface layer of freshly-fallen guano has the greatest diversity of taxa, with Bacteroidota co-dominant with Pseudomonadota, and includes many taxa unique to this …

Assessment Of Tce And Chiral Pcb Dechlorination Rate, Congener Diversity, And Enantioselectivity In Town Creek, Sc, Usa Sediment Microcosms, Catherine P. Sumner

All Dissertations

Polychlorinated biphenyls (PCBs) and trichloroethene (TCE) are ubiquitous contaminants and are recognized as persistent organic pollutants due to their extreme chemical stability. PCBs were manufactured by chlorinating biphenyls that created 209 congeners with various structures, of which 19 are chiral and can exist as a pair of stable atropisomers. PCBs have been known to cause developmental and neurological toxicity in humans and wildlife; they can act as endocrine disrupters, carcinogens, and teratogens. Sangamo Weston Inc. was an industrial plant located near Town Creek in Pickens Country, South Carolina, that manufactured capacitors and used Aroclors 1016 and 1254 as dialectic fluids …

Heavy Metals Implications To Sediment Microbiome And Coral Response To Arsenic Dosing, Dimitrios G. Giarikos, Amy Hirons, Jose V. Lopez, Abigail Renegar, Jason Gershman

SECLER Data

No abstract provided.

Antibiotic Resistance In A Coastal River In Mississippi, Usa – Potential Drivers, Shuo Shen, Wei Wu, Eric A. Saillant, Darrell Jay Grimes

Gulf and Caribbean Research

Wastewater treatment plants (WWTPs) are major sources of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in water bodies. Most studies on the impact of WWTPs on antibiotic resistance have focused on freshwater systems, with little information on coastal and estuarine waters with variable salinity. This study monitored seasonal levels of ARGs at the effluent and downstream of the Pascagoula— Moss Point WWTP in the lower Pascagoula River, a coastal river in southeastern Mississippi, USA. Surface water samples were collected seasonally at upstream, outflow, and 3 downstream sites from February to November 2016. Bacterial resistance to sulfamethazine, tetracycline, and …

Developing Methods For Analysis Of Chiral Small Molecules And D-Amino Acid Containing Peptides, Joshua I. Putman

Chemistry & Biochemistry Dissertations - Archive

This dissertation covers the development of methods to analyze chiral small molecules and d-amino acid containing peptides. The first section covers the development of liquid chromatographic chiral screening approaches for newly synthesized chiral molecules. The next part of the dissertation covers methodologies for the analysis of d-amino acid containing peptides. Lastly the bacterial degradation of three commonly used pesticides by bacteria harvested from Colorado potato beetles (Leptinotarsa decemliniata) is presented.

Twelve new azole compounds and eleven racemic ethanolamine derivatives were synthesized. These twenty-three compounds were evaluated using eight chiral columns, four macrocylic glycopeptides, a cyclodextrin derivative …

Examining The Role Of Microbial Communities In Soil Carbon Cycling Across Levels Of Complexity, Chansotheary Dang

Graduate Theses, Dissertations, and Problem Reports (ETD)

Microorganisms provide the foundation for many ecosystem processes and are important drivers of carbon and nutrient cycling. The advancement of next generation sequencing has allowed researchers to lift open the lid on the ‘black box’ in microbial ecology. While previously unculturable microbes can now be characterized with the 16S rRNA gene, answering ‘who’s there?’ is only part of the challenge. Hidden inside the ‘black box’ remains the question, ‘who’s doing what?’. Recent development in trait-based methods like quantitative stable isotope probing (qSIP) equipped microbial ecologists with the tool to connect taxon-specific traits to ecosystem processes. Despite the growing body of …

Interactions Between Multiple Stressors, Nanomaterials And A Pathogen, In Caenorhabditis Elegans, Jarad Cochran

Theses and Dissertations--Plant and Soil Sciences

Metal and metal oxide nanoparticles (NP), which have received interest for use in agriculture, show in vitro and in vivo toxicity at relatively low concentrations. Silver nanoparticles (Ag NP) and zinc oxide nanoparticles (ZnO NP) cause adverse effects in model soil organisms under environmentally relevant conditions. In most toxicity assessments of nanomaterials, model organisms are exposed to a single stressor. Though single stressor experiments are essential to understanding the fate and effects of released NP, in nature, organisms are affected by multiple stressors, including pathogens, which might exacerbate or mitigate negative effects of NP exposure. There is limited research on …

Dust-Driven Mechanism For Marine Particle Aggregation: Interactions Between Clay Minerals, Heterotrophic Bacteria And Organic Matter Influences Aggregation In Marine Systems, Vignesh Gokuladas Menon

Dartmouth College Master’s Theses

Atmospheric dust deposition plays a crucial role in marine biogeochemical cycles, yet mechanisms underlying its impact on particle dynamics remain unclear. This study investigates the synergistic interactions between marine heterotrophic bacteria and clay minerals in seawater, focusing on their effect on Transparent Exopolymer Particles (TEP) production and organoclay aggregation. Field experiments in the Gulf of Maine and laboratory roller tank studies were conducted using natural microbial communities and model heterotrophic bacterial strains (Alteromonas sp. EZ55, Marinobacter adhaerens HP15, and Sulfitobacter sp. NAS-14.1). Results demonstrate that clay exposure significantly enhances TEP production by bloom-associated heterotrophic bacteria, with increases up to …