Digital Commons Network^™

Reconnecting With Nature One Classroom At A Time, Bianca Apuzzo

Senior Honors Projects

Environmental science is more important to today’s society than it has ever been, and developing basic ecoliteracy is the easiest way we can work towards a more sustainable future. Ecoliteracy allows us to connect deeper to nature and provides us with the information needed to protect and restore our beautiful planet. We are rolling downhill, picking up speed as we go, through a silent mass extinction. The scariest part of it all: nobody seems to care.

In response to the lack of environmental education provided to today’s students, I have created a syllabus for a high school level science course …

The Influence Of Edaphic Factors On The Growth And Competitiveness Of Loosestrife (Lythrum Spp.), Martha Mahady

Theses, Dissertations and Culminating Projects

Wetlands are important areas in the landscape, providing important ecosystem services. Purple loosestrife (Lythrum salicaria), native to Europe and Asia, invades wetlands in North America, outcompeting native wetland plants and disrupting ecosystem services. While purple loosestrife is invasive in North America, it is not in its native range. Winged loosestrife (Lythrum alatum), a North American native congener, is not invasive in North America. Purple loosestrife from Sussex County, N.J. U.S.A. and purple loosestrife from the United Kingdom, and winged loosestrife were compared in this study. Their response to soil edaphic factors, such as seed vernalization, soil nutrients, soil pH, water, …

A Global Analysis Of Carbon And Nitrogen Stocks In Natural And Anthropogenic Soils, Shih-Chieh Chien

Theses, Dissertations and Culminating Projects

In terrestrial biomes, soils possess the highest amount of carbon and nitrogen stocks that regulate biogeochemical processes and provide ecosystem services. The amount of carbon and nitrogen stored in soils, as a balance of nutrient influxes and outfluxes, is controlled by various environmental and soil factors, while at the same time soil carbon and nitrogen stocks can be subject to anthropogenic impacts, like nutrient storage in urban soils. To inform a better, general understanding of carbon and nitrogen distribution in urban soils, the present dissertation gathers four articles (from Chapters 2 to 5, respectively) addressing different aspects of the issue, …

Evaluation Of Heavy Metal Pollution, Water Quality, And The Effectiveness Of Remedial Sediment Dredging In The Lower Passaic River, New Jersey, Oluwafemi Soetan

Theses, Dissertations and Culminating Projects

Toxic metal pollution is a leading environmental concern for aquatic systems globally and remedial dredging has been widely employed to mitigate its harmful impacts. In terms of the short-term impacts of remedial dredging, mixed results are reported in several studies. Despite its immediate negative impacts including saturation of water with toxic metals, increased turbidity, and sediment resuspension, positive impacts can be recorded over a stabilization period of 6 – 24 months after dredging. Nevertheless, the sustainability of these recorded positive effects cannot be ascertained as some studies have reported long-term regression in remediated sites’ conditions. Evaluation of success determinants, site-measure …

Barrier Removal Prioritization To Increase Climate Resiliency And Aquatic Connectivity For Communities In The Upper Susquehanna Basin, Cassandra Mae Davis

Legacy Theses & Dissertations (2009 - 2024)

The streams and rivers of the Upper Susquehanna Basin have been heavily modified over centuries through deforestation of nearshore areas and creation of physical barriers, such as dams and culverts. Dams and undersized culverts negatively affect aquatic organisms by modifying habitat conditions and restricting movement of these organisms. In addition, improperly maintained dams and undersized culverts can intensify flooding impacts and negatively affect water quality. A standardized method is needed to determine which barriers should be prioritized for assessment and potential replacement or removal based on multiple ecosystem and societal factors. The goal of this analysis was to have a …

The Water That Will Be: A Qualitative Look Into The Effects Of Visual Imagery On Participation In Water Conservation Initiatives, Shane Martin White

Graduate Theses and Dissertations

This dissertation explored the role of visual imagery in water conservation initiatives, focusing on its impact on public understanding, emotional connection, and willingness to participate. Drawing from the Theory of Planned Behavior and Affective Disposition Theory, the study investigated how art interventions can enhance comprehension and engagement with water conservation easements. Utilizing qualitative methods, including interviews, focus groups and PhotoVoice, data was collected from stakeholders in the Illinois River Watershed region. The research examined current levels of understanding regarding conservation easements, evaluated the effectiveness of visual imagery interventions in enhancing public awareness, and identified the potential for collaborative approaches between …

Screening Full-Sib And Half-Sib Families Of Chestnut Seedlings For Resistance To Cryphonectria Parasitica Using A Small Stem Assay And A Leaf-Disc Assay, Uma Plambeck

Honors Theses

Cryphonectria parasitica is the ascomycete fungus species that causes chestnut blight disease. Symptoms of chestnut blight include bark cankers and eventually the death of American chestnut, Castanea dentata. However, not all Castanea species are equally affected by the disease, and some Asian species appear highly resistant. The OALDS and SSA in this study aim to assist in screening for resistance to C. parasitica within a year. We investigated the effect of C. parasitica on three North American species, one European species, four East Asian species of Castanea, and nine full-sib families of TACF backcross hybrids. Our study used both a …

Dispersal And Population Structure Of Euchlanis Chihuahuaensis Via Anemochory In The Chihuahuan Desert, Tristan Chavez-Poeschel

Open Access Theses & Dissertations

Desert ecosystems present challenges for aquatic organisms as habitats are fragmented, both in space and time; however, diapausing stages of rotifers can travel hundreds of kilometers during wind events. I used the rotifer Euchlanis chihuahuaensis as a model species to investigate the influence of wind dispersal on gene flow and population genetics in Chihuahuan Desert populations. I hypothesized that anemochory facilitates gene flow from source populations in the Northern Chihuahuan Desert in Mexico and the western United States to habitats in the Trans-Pecos region via delineated wind corridors. To test this hypothesis, the genetic diversity of populations from both inside …

Do Heat Waves Drive Natural Selection In Damselflies?, Adam Baranyk

Biological Sciences Undergraduate Honors Theses

Climate change has led to changes in both mean temperatures and temperature extremes over the recent years. These changes have had differential effects on animals throughout the world. Ectotherms depend on their external environment for thermal regulation, making them especially susceptible to temperature extremes. It is not yet clear whether there is a relationship between physical traits in ectotherms, and survivorship throughout a heat wave. That is, whether or not temperature extremes driven survival selection. In this study, a heat wave was simulated artificially using thermally regulated mesocosms at different temperatures (18°C, 22° C, 26° C, 30° C) with a …

Modification, Transport, And Sources Of Hydrocarbon Oxidation Products From Groundwater At Crude Oil And Diesel Spill Sites In Minnesota: Unveiling Common “Theems” Via Spectroscopy & Chromatography, Eduardo E. Turcios Valle

LSU New Orleans Theses and Dissertations

In this thesis, petroleum-contaminated groundwater from three spill-affected Minnesota sites—two contaminated with crude oil; one with diesel—is investigated to elucidate whether differences in degradation products from different parent oils exist. After spill events, parent molecules from the leaked oil seep underground and undergo microbial degradation over time, transforming into hydrocarbon oxidation products (HOPs), water-soluble contaminants that infiltrate groundwater aquifers, flowing into nearby environments and towns while exhibiting environmental persistence, toxicity to aquatic biota, and potential risks to humans that become exposed. Spectroscopic and chromatographic study of the structural themes and spatial distributions of HOPs reveals preferential degradation of aliphatic (biolabile) …

Chemical Composition, Fate, And Toxicity Of Dissolved Hydrocarbon Oxidation Products In High Latitude Aquatic Environments, Maxwell Louis Harsha

LSU New Orleans Theses and Dissertations

Oil spilled in aquatic environments undergoes abiotic and biotic oxidation processes that produce hydrocarbon oxidation products (HOPs). HOPs rapidly diffuse in the water column, persisting and readily bioavailable to aquatic organisms. Characterizing HOPs is challenging because most of the mixture resides in the unresolved complex mixture (UCM). Understanding of the formation, fate, and toxicity of HOPs in high latitude environments remains limited. This research addresses these gaps through a comprehensive experimental approach, utilizing various analytical techniques including nonvolatile dissolved organic carbon (NVDOC) analysis, ultrahigh-resolution mass spectrometry, tandem mass spectrometry, inductively coupled plasma mass spectrometry, and fluorescence excitation-emission matrix spectroscopy. Additionally, …

Examining The Relationship Between Manning's Roughness Coefficient And Stage, Henry Holtkamp

Biological and Agricultural Engineering Undergraduate Honors Theses

This paper uses LOESS regression to predict Manning's roughness coefficient to calculate flows in natural stream channels. Manning's roughness coefficient can introduce variability into Manning's equation, potentially destabilizing results. Utilizing LOESS to find n based on backcalculated n from collected discharge vs. stage information is the best way to acquire accurate Manning's roughness coefficient values at a variety of flows. Book values tend to drastically overestimate which can have wide-ranging implications for water allocation, flood management, maintaining environmental flows, and maintaining water quality.

Evaluating Novel Approaches For Improving Anadromous Fish Passage In Coastal Rivers, Aaron Bunch

All Dissertations

Few of the world's rivers remain free-flowing for over 1000 km, significantly impacting anadromous fish populations due to dam-induced habitat fragmentation. Three partial migration barriers (low-head dams) on North Carolina's Cape Fear River (USA)—lock and dam 1 (LD1), lock and dam 2 (LD2), and lock and dam 3 (LD3)—impact American shad Alosa sapidissima, Atlantic sturgeon Acipenser oxyrinchus oxyrinchus, and striped bass Morone saxatilis populations. Mitigation strategies to pass fish upstream have included conservation locking, nature-like fishway construction, and environmental flows (e-flows). This study introduced a novel e-flow (dam submergence flow), tested acoustic double-tagging techniques for tracking American …

Water Sufficiency For Organismal Function In Dryland Critical Zones, Lindsey Dacey

Open Access Theses & Dissertations

Water availability is crucial for organismal survival and growth in dryland environments, affecting both ecological interactions and carbon dynamics. The goal of this thesis is to develop soil water release curves (SWRCs) that link soil water potentials (Ψ) to soil water content (θ). Using the SWRCs, temporal soil water sufficiency curves are developed, which quantify the amount of time that dryland critical zones have enough water to sustain the physiology of organisms. These curves allow for effectively indicating water availability across different species, coverage types, and soil conditions, enhancing our understanding of water dynamics in drylands and contributing important parameters …

Assessing Nordihydroguaiaretic Acid Properties And Its Potential Therapeutic Effect For Glioblastoma, Jose Arturo Guerrero

Open Access Theses & Dissertations

This study employs a combination of theoretical and experimental analysis to spectroscopically investigate the biomechanistic structure relationship and therapeutic effects of the Nordihydroguaiaretic Acid (NDGA) chemical derived from the Larrea Tridentata plant. These relationships are crucial for understanding NDGA's efficacy in disease prevention, treatment, and potential toxicological effects. While the medicinal and antiviral properties of the NDGA have been studied extensively, there remains a gap in optically identifying and reporting its structural changes. The current research successfully reveals evident trends in NDGA's vibrational signatures, particularly highlighting the absence of the Raman feature at 780 〖cm〗^(-1) as indicative of a fully …

Conversion Of Microcrystalline Cellulose To Hexane Using Hydrogenated Metal Oxides At Low Temperature And Pressure, Mubarak Osman

Electronic Theses and Dissertations

Increasing global energy demand and environmental concerns have fueled the exploration of sustainable and efficient methods for renewable fuel production. The conversion of cellulosic waste to hydrocarbon fuels using hydrogenated metal oxides presents a novel and eco-friendly approach to sustainably address energy demand. In this study, hydrogenated metal oxides were used as catalysts in a relatively low-temperature and atmospheric-pressure environment to facilitate the conversion of cellulosic waste into hydrocarbon fuels. Hydrogenated metal oxides have been introduced as potential hydrogen transfer catalysts. The expected result is the selective conversion of cellulose to hexane at relatively low temperatures, which significantly reduces energy …

Sheep Grazing Influences The Abundance, Diversity, And Community Composition Of Wild Bees And Other Insects In Livestock Pastures, Roshani Sharma Acharya, Timothy B. Leslie, Joan Burke, Kusum Naithani, Emily Fitting, Kelly Loftin, Neelendra K. Joshi

Entomology and Plant Pathology Faculty Publications and Presentations

Pollinators contribute to the establishment of perennial native forages, but little is known about the effect of grazing practices on pollinator abundance and diversity in livestock pasture ecosystems. Grazing reduces floral resources available to bees and other insects, and as a result, may influence their communities. The main objective of this study was to examine the impact of sheep grazing on bees and other non-bee insects in livestock pasture established with seed mixes of native forb/legume/grass and warm season grasses. Each pasture was divided into two halves (in a split-plot design) using an electric fence in which one plot was …

How Does Hummock Creation In Submerging Salt Marshes Alter Nitrous Oxide Fluxes?, Juliette Doyle

Honors Scholar Theses

Climate change is altering ecosystems and the services they provide. Salt marsh ecosystems typically protect coastal areas and filter nitrogen out of water, but are rapidly submerging due to rising sea levels and human development that prevents landward migration. Recent restoration efforts to preserve salt marshes attempt to build elevation capital and promote vegetation and animal habitat, but it is unclear how such efforts affect salt marsh biogeochemistry and dynamics of nitrous oxide, a potent greenhouse gas. To better understand how adding sediment to submerging salt marshes may alter nitrous oxide fluxes, I leveraged a salt marsh hummock creation experiment …

The Impacts Of Wind On Coastal Trees, Julian Halil

All Theses

Trees in hurricane-prone areas are exposed to severe winds and flooding. We studied the physiological and structural responses of forested wetland trees in relation to wind stress. We evaluated the windfirmness of two forested wetland tree species. Baldcypress was chosen because of high survival in post-hurricane studies. In contrast, laurel oak co-occurs with baldcypress yet resists hurricane-force winds poorly. In a static winching study, we quantified the critical turning moment (Mcrit) required to topple both species. Mcrit increased with trunk diameter at breast height (DBH) and crown size. Baldcypress and laurel oak demonstrated similar Mcrit, but regression models indicate baldcypress …

High Intraspecific Diversity Of Pocillopora Damicornis In Southeast Asia Reflects Adaptive Potential To Climate Change, Maria Lucille Carr

Theses and Dissertations

Marine heatwaves are increasing in intensity and frequency because of increased emissions of greenhouse gases. On coral reefs, warmer temperatures cause coral bleaching, mortality, and shifts in benthic composition. However, coral bleaching responses and survival vary geographically. Several hypotheses may explain such geographical differences in thermal tolerance, including the possibility that some localities may support higher intraspecific diversity than other localities, increasing the likelihood of survival of some individuals through heatwaves. Here we assessed geographic patterns of intraspecific genetic diversity in the ubiquitous coral Pocillopora damicornis. Intraspecific genetic diversity was assessed for 428 sequences across 44 sites in the Pacific …

Do You Know The Pangolin?: Analyzing Biodiversity Awareness And Attitudes, Ariel "Jazz" Holcomb

Honors Theses

Understanding the impact education has on environmental knowledge and values is critical for knowing how we can promote pro-environmental awareness and attitudes. Thus, this study investigated how environmental education level influences awareness and attitudes on environmental issues, specifically the Biodiversity Crisis. Through a survey primarily utilizing Likert scale statements, the researcher evaluated the differences in knowledge and care levels between classes taking an introductory environmental science course, one class of environmental science majors and one for non-majors. One focus point of the course is the world’s most trafficked mammal, the pangolin, so this species was used as a focus species …

Impacts Of Lake Elevation Decline On Tui Chub, A Critical Forage Species For Lahontan Cutthroat Trout In Pyramid Lake, Nevada, Usa, Sarah Barnes

All Graduate Theses and Dissertations, Fall 2023 to Present

Lake level decline affects lakes worldwide, changing the availability and character of nearshore habitat used by fish to spawn, and increasing total dissolved solids (TDS), similar to salinity, a factor that negatively impacts fish health. Lake level decline can affect different lakes in different ways, but typically when lake level declines significantly, there is less nearshore habitat overall, and what nearshore habitat remains has less diverse habitat for fish. We investigated whether both impacts of lake level decline may be causing declines of Tui Chub Siphateles bicolor, a large minnow native to Pyramid Lake that spawns in nearshore habitat. …

Comparing The Regulatory Effects Of Overexpressed Micrornas And Xenobiotic Drugs On Cell Cycle And Apoptotic Regulators In Pc-3 Cells, Tommie Johnson

Dissertations (2016-Present)

MicroRNA was first discovered in C. elegans as small temporal RNA (stRNA) that does not code for protein. Since being discovered they have played a significant role in regulating gene expression at the post-transcriptional level. miRNAs are found in various organisms, and they bind to the 3' untranslated regions to inhibit translation and cause mRNA degradation. Some drugs are involved in cell cycle regulation such as Palbociclib, Ribociclib (LEE011), and Abemaciclib (LY2835219), that causes G1 arrest impeding cell proliferation. Cyclin D1 (CCND1) is supported by the cell cycle making it into a functional product. When undergoing a chemical reaction, the …

Eco-Anxiety Effects College Students, Alexa Edmundson

Department of Environmental Studies: Undergraduate Student Theses

A survey was conducted on the UNL student population to evaluate whether college students, 18-25 year olds who are currently attending an accredited post-secondary school, are experiencing eco-anxiety and if eco-anxiety affects their pro-environmental behaviors. Climate change is taking a toll not only physically on us but also mentally. The mental health of people, especially college students, is not often studied in relation to climate change, but if we are to understand how to create change in this issue then we need to be looking at the whole picture. The hypothesis is that if college students are experiencing eco-anxiety, then …

A Best Way Forward To The Organisation Of Entomological Training Courses In Sub-Saharan Africa, Kurt Jordaens, Marc De Meyer, Muriel Van Nuffel, Ashley H. Kirk-Spriggs, Christopher Sabuni, Maulid Mwatawala, Ramadhani Mujabwa, Sija Kabota, Terence Bellingan, Georg Goergen, Mervyn Mansell, Aruna Manrakhan, Antonio Sinzogan, Mark K. Schutze, Arianna Thomas-Cabianca, Robert Copeland, Burgert Muller, Massimiliano Virgilio, Ella Bert, Eva November, John Midgley

All Peer-Reviewed Publications

Despite their significant impact on human life in the Afrotropical Region, Diptera remain understudied. For a large part this is due to a lack of Diptera taxonomic experts and collection curators from the Afrotropical Region (except for South Africa perhaps), the difficulties some developing countries face in maintaining collections, and the low number of digitised specimens. This impedes the use of these Diptera collections for identification services, taxonomic and phylogenetic research, and other biological research areas. The dire need for knowledge transfer and training of young and emerging entomologists in the Afrotropical Region has prompted the Royal Museum for Central …

Use Of Modelling Tools To Assess Climate Change Impacts On Smallholder Oil Seed Yields In South Africa, Priscilla Ntuchu Kephe, Siyabusa Mkuhlani, Farirai Rusere, Abel Chemura

All Peer-Reviewed Publications

Oil seed crops are the second most important field crops after cereals in the agricultural economy globally. The use and demand for oilseed crops such as groundnut, soybean and sunflower have grown significantly, but climate change is expected to alter the agroecological conditions required for oilseed crop production. This study aims to present an approach that utilizes decision-making tools to assess the potential climate change impacts on groundnut, soybean and sunflower yields and the greenhouse gas emissions from the management of the crops. The Decision Support Tool for Agrotechnology Transfer (DSSAT v4.7), a dynamic crop model and the Cool Farm …

Combining Temperature-Dependent Life Table Data Into Insect Life Cycle Model To Forecast Fall Armyworm Spodoptera Frugiperda (Je Smith) Distribution In Maize Agro-Ecological Zones In Africa, Marian Adan, Henri E.Z. Tonnang, Cojdo E.F. Kassa, Klaus Greve, Christian Borgemeister, Georg Goergen

All Peer-Reviewed Publications

The fall armyworm (FAW), Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae), an invasive agricultural pest, has significantly impacted crop yields across Africa. This study investigated the relationship between temperature and FAW life history traits, employing life cycle modeling at temperatures of 20, 25, 28, 30, and 32̊C. The development time for eggs, larvae, and pupae varied from 0–3 days, 10–18 days, and 7–16 days, respectively. The optimal temperature range for immature stage survival and female fecundity was identified as 21–25̊C, with the intrinsic rate of increase (rm) and gross reproductive rate (GRR) peaking at 25–28̊C. Model validation confirmed the accuracy of …

Catchment-Scale Thawing And Greening Decreases Long-Term Nitrogen Export In Ne Greenland, Shannon L. Speir, Jennifer L. Tank, Ada Pastor, Marc F. Muller, Mikhail Mastepanov, Tenna Riis

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Climate change is expected to alter nitrogen (N) export from Arctic rivers, with potential implications for fragile coastal ecosystems and fisheries. Yet, the directionality of change is poorly understood, as increased mobilization of N in a 'thawing' Arctic is countered by higher rates of vegetative uptake in a 'greening' Arctic, particularly in the understudied region of Greenland. We use an unprecedented dataset of long-term (n = 18 years) river chemistry, streamflow, and catchment-scale changes in snow and vegetation to document changing riverine N loss in Greenland. We documented decreasing inorganic and organic N loads, linked to decreasing snow stores, …

Seasonal Climate And Environmental Conditions Associated With Physiological Variations Of Southwestern United States Pines, Taylor Brewer

UNLV Theses, Dissertations, Professional Papers, and Capstones

Juvenile and adult conifers in the southwestern United States are vulnerable to a range of different abiotic and biotic factors, yet it is unclear how their stress tolerance varies across environments. Predicted increases in the frequency and intensity of disturbance as well as greater climate and weather variability across the region highlight the potential for differential physiological responses across tree species and populations. This thesis focuses on two physiologic mechanisms, hydraulic vulnerability and mortality, that could be altered by climate change in two broadly distributed southwestern United States conifers: ponderosa pine and pinyon pine.

In chapter 2, I measured the …

Plant-Plant Interaction In Early- Vs. Late-Successional Varieties Of The Hawaiian Landscape-Dominant Tree, Metrosideros Polymorpha, Tomoko Sakishima

UNLV Theses, Dissertations, Professional Papers, and Capstones

Plant-plant interactions play an important role in assembling plant communities. Interactions between neighboring plants can vary as a result of the genetic relatedness of neighbors, impacting rates of growth and patterns of resource allocation. When growing alongside close relatives, some species decrease their growth in a form of cooperation, while others grow faster through facilitation. A complication of plant interaction studies arises because decreased growth in the presence of close relatives can also be due to competition for resources, which increases with phenotypic similarity. Further complicating matters, mycorrhizal fungi, through their connections with plant roots, may strongly influence plant interactions. …