Life Sciences Commons^™

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 …

Use Of Unoccupied Aerial Vehicle (Drones) Based Remote Sensing To Model Platform Topography And Identify Human-Made Earthen Barriers In Salt Marshes, Joshua J. Ward

Masters Theses

Elevation is a foundational driver of salt marsh morphology. Elevation governs inundation and hydrological patterns, vegetation distribution, and soil health. Anthropogenic impacts at grand scales (e.g., rising sea levels) and local scales (e.g., infrastructure) have altered the elevation of the salt marsh surface, changing the topography and morphology of these ecosystems. This study establishes and assesses means to document and analyze these impacts using Unoccupied Aerial Vehicle (UAV) based remote sensing to model platform topography. This thesis’s first and primary study presents and compares methods of producing high-resolution digital terrain models (DTMs) with UAV-based Digital Aerial Photogrammetry (DAP) and Light …

Interactive Effects Of Sublethal Concentrations Of Fracking Biocides And Abandoned Mine Drainage On Amphipod Behavior, Kelly Lenhart

Electronic Theses and Dissertations

This thesis examined the sublethal effects of three pollutants, namely glutaraldehyde, 4,4-dimethyloxazolidine (DMO), and abandoned mine drainage (AMD), on amphipods. The primary objective was to investigate their combined effects on amphipods. The three pollutants, despite having the potential to combine in the environment, have not been studied to determine their potential for detrimental interactive effects which could result in unexpected environmental damage.

The research employed a series of experimental setups involving controlled exposure of amphipods to varying, putatively sublethal, concentrations of the chemicals of interest. Subsequently, effects were assessed via both behavioral and feeding assessments. To facilitate this analysis, novel …

Targeting Macrophytes: Increased Water Quality Through Optimized Vegetation Considerations For Constructed Wetlands, Austin Mcbrady

Masters Theses

This study of constructed wetland design investigated relationships between macrophyte species selection and planting density for water quality improvement. A lab-scale wetland was compared against a pilot-scale wetland in San Antonio, Texas at Mitchell Lake to measure differences in effluent water quality improvement using three native macrophyte species. Using a novel, two-phase method, a targeting macrophyte was identified from among other species based on its marked capability for improving water quality factors, then was planted in varied majority densities to compare differences in treatment effectiveness. The results of this study showed that this complimentary approach to wetland design displayed significant …

Environmental And Agronomic Evaluation Of Struvite In Rice Production Systems, Diego Della Lunga

Graduate Theses and Dissertations

Furrow-irrigation constitutes an alternative water regime that has been increasingly adopted in Arkansas. Among the management of nutrients in furrow-irrigated systems, phosphorus (P) represents a substantial challenge. The environmental sustainability of rice (Oryza sativa) production systems needs to be evaluated across different water regimes and fertilizer-P sources. Therefore, the objectives of the following studies were to: i) evaluate season-long carbon dioxide (CO2) and methane (CH4) emissions and global warming potential (GWP) under different tillage treatments [i.e., conventional tillage (CT) and no-tillage (NT)] and at different site positions (i.e., up-, mid-, down-slope) along the predominant slope of a production-scale, furrow-irrigated rice …

Fire Effects On Soil Organic Matter In The Creek Fire, Gracie E. Doolin

Master of Science in Environmental Sciences and Management Projects

Wildfires have increased in frequency and severity over the past few decades due to the increased concertation of CO2 emissions from anthropogenic influence. Soil carbon (C) sequestration has been identified as a climate change mitigation strategy; however, the influx of large-scale wildfires has accelerated landscape processes such as erosion, reducing soil aggradation, and soil C and nitrogen (N) protection. This trend is highlighted by the Creek Fire that occurred in September 2020 and burned 379,895 acres in the Sierra National Forest. This research is designed to close the knowledge gap regarding the impact of burn severity on soil organic matter …

Distribution And Habitat Associations Of The Georgia Satyr (Neonympha Areolatus) In Arkansas, Kristi Patterson

ATU Theses and Dissertations 2021 - Present

The Georgia satyr (Neonympha areolatus) is a small sedentary butterfly that is rare in Arkansas. Currently, the exact locations of this butterfly in Arkansas are unknown, along with the habitat characteristics associated with their presence. In order to determine these unknowns, I completed 104 surveys across seven different wildlife management areas in southern Arkansas. Pollard-Yates transects were conducted at each study site, and weather variables were recorded before each survey. Vegetation surveys were also completed at each site, and where each Georgia satyr was identified. Generalized linear models (GLM) were created to identify what parameters are important for …

Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed

Graduate Theses and Dissertations

This dissertation explores the application of remote sensing technologies in conservation agriculture, specifically focusing on identifying and mapping winter cover crops and assessing voluntary cover crop adoption and cropping patterns in the Arkansas portion of the Mississippi Alluvial Plain (MAP). In the first chapter, a systematic review using the PRISMA methodology examines the last 30 years of thematic research, development, and trends in remote sensing applied to conservation agriculture from a global perspective. The review uncovers a growing interest in remote sensing-based research in conservation agriculture and emphasizes the necessity for further studies dedicated to conservation practices. Among the 68 …

Characterization Of Boreal-Arctic Vegetation Growth Phases And Active Soil Layer Dynamics In The High-Latitudes Of North America: A Study Combining Multi-Year In Situ And Satellite-Based Observations, Michael G. Brown

Dissertations, Theses, and Capstone Projects

This dissertation examined the seasonal freeze/thaw activity in boreal-Arctic soils and vegetation physiology in Alaska, USA and Alberta, Canada, using in situ environmental measurements and passive microwave satellite observations. The boreal-Arctic high-latitudes have been experiencing ecosystem changes more rapidly in comparison to the rest of Earth due to the presently warming climatic conditions having a magnified effect over Polar Regions. Currently, the boreal-Arctic is a carbon sink; however, recent studies indicate a shift over the next century to become a carbon source. High-latitude vegetation and cold soil dynamics are influenced by climatic shifts and are largely responsible for the regions …

Determination Of Cadmium Uptake In Crassostrea Virginica Shell Under Controlled Conditions, Joseph John Pavelites Ii

<strong> Theses and Dissertations </strong>

The objective of this thesis was to meet growing demand for the development of environmental biomonitors that protect ecosystems and public health. To do this, I determined the potential of oyster shell as a bioindicator of cadmium (Cd) in the environment by determining the mode of Cd uptake and relationships between Cd concentrations in the environment, shell, and soft tissues of juvenile eastern oysters (Crassostrea virginica Gmelin). I performed a review of the literature on the ability of oyster shell to retain metal contaminants and the factors that could affect this process (Chapter 2). I then reared C. virginica …

Geomorphology Of Tidal Wetlands: Impacts Of Extreme And Annual Flood Events To Salt Marsh And Mangrove Systems, Frances R. Griswold

Doctoral Dissertations

Tidal wetlands are vital for buffering coastal settings from the threats of accelerated sea level rise and storms. Understanding the factors that are most influential for the maintenance and recovery of tidal wetlands after extreme events compounded by future accelerated sea level rise is of the utmost importance, yet this knowledge is not well established. Two tidal wetland schemas investigated in this dissertation are mangrove systems in Vieques, Puerto Rico (including robust lagoonal-mangrove forest systems and fringing mangrove forests), and salt marshes in New England. While the climatic forcings, vegetation type, and locations are vastly different for these two tidal …

National Development And The Sustainability Of Mining In The Atacama Desert, Chile, Dakota Soleil Osgood

Capstone Collection

As climate change continues to intensify on a global scale, efforts have been made to implement renewable energies and progressive technologies. These tools are critical in the shift towards a more sustainable practice, and yet analysis of localized impacts from the development of these mechanisms is inadequate. Chile has been and continues to be a leading country in mineral extraction, with an economic history founded in the mining industry. The establishment of mining in Chile as a progressive tool has aided the social and economic development of the nation. Consequences of mining extraction, however, include intensive environmental degradation, human rights …

Assessing Ecotoxicity Of Surface Water And Sediment In The Little Scioto River, Leah Suzanne Morgan

Theses, Dissertations and Capstones

Aquatic toxicology evaluates the impact of pollution on freshwater and marine biota. Polycyclic aromatic hydrocarbons (PAHs) are one class of chemicals prevalent in the environment that impair aquatic organisms. This study examined the effect of contaminated surface water and sediments from a former wood treatment facility on four aquatic species: Pimephales promelas (fathead minnow), Ceriodaphnia dubia (water flea), Chironomus dilutus (midge), and Daphnia magna (water flea). The findings showed that sediment contamination had no significant effect on survival and growth of C. dilutus or on survival of D. magna. Surface water contamination began to have a significant effect on …

Characterizing The Vegetation And Effects Of Climate Change On Parris Island, A Sea Island Ecosystem, Cody Hart Goodson

Theses, Dissertations and Capstones

Coastal habitats provide many ecosystem services, protecting coastlines from storm surges and erosion, diminishing the effects of eutrophication, sequestering large amounts of carbon, and acting as vital wildlife habitat. Sea-level rise and increased storm surge intensity associated with climate change are increasingly disrupting coastal habitats. These disturbances can shift environmental gradients that drive the zonation of coastal vegetation types, driving habitat conversion. Monitoring coastal habitat conversion can improve our understanding of the dynamic effects of climate change on these landscapes. Therefore, our objectives for chapter 1 were to identify and describe the distributions of vegetation types present on Marine Corps …

Prevalence Of Hesperevax Sparsiflora Var. Brevifolia (Short-Leaved Evax) At Ocean Ranch, Humboldt County, California: Exploring The Effects Of Disturbance, Shelby Diquirco, Matthew Estrada, Alana T. Fraley, Alexander D. Smith

Environmental Science & Management Senior Capstones

The prevalence of special-status plants within a landscape can be an indicator of the ecological health of that site, and therefore inform restoration efforts and post-restoration monitoring. Hesperevax sparsiflora var. brevifolia (short-leaved evax) is a special status species found within the Ocean Ranch unit of Humboldt, California. A primary threat to native plant communities are invasive plant species. Coastal dune ecosystems are largely dominated by invasive species, including Ammophila arenaria (European beachgrass). To work towards the eradication of A. arenaria, the California Department of Fish and Wildlife utilized treatment combinations of herbicide and prescribed fire at Ocean Ranch in …

How Akron Affects The Water Quality Of The Cuyahoga River, Allyson Darst

Williams Honors College, Honors Research Projects

The purpose of this study was to analyze whether the city of Akron had negative effects on the Cuyahoga river, and determine if the Cuyahoga River was naturally able to remediate these effects downstream. The pollutants measured in this study include hardness, bromine, residual chlorine, iron, copper, lead, nitrate, nitrite, ammonium chloride, total chlorine, fluoride, carbonate, pH, total alkalinity and cyanuric acid. This study was done using water testing strips (JNW Direct) to test the water at four different locations along the Cuyahoga River downstream (North) of Akron. This study found that the city of Akron does have a negative …

Understanding The Impacts Of Anthropogenic Effects An Habitat Variability Interactions On Maine's Rocky Intertidal Ecosystem, Laura Braun

Electronic Theses and Dissertations

The rocky intertidal ecosystem is an important ecological and cultural aspect of the picturesque Maine coast, playing a vital role in not only Maine’s coastal ecosystem, but also to Maine’s economy. It’s distinct community structure along the sharp elevational gradient and the presence of daily stressors (wave action, heat, and desiccation), make the rocky intertidal ecosystem an important model ecosystem to monitor for effects from anthropogenic impacts. In this thesis, I describe attempts to monitor and understand the impacts of two of these anthropogenic impacts on this system: climate change and industrial harvesting of Ascophyllum nodosum along Maine’s coast. For …

Sustainability And Health Impacts Of Pulse Crops In The United States Using Life Cycle Assessment, Prathamesh A. Bandekar

Graduate Theses and Dissertations

Environmental sustainability and human health impact of pulses produced and consumed in the United States was assessed using life cycle assessment (LCA). The study included three objectives 1) to estimate environmental impact of current production and consumption practices in the United States using attributional LCA; 2) to estimate environmental and human health impact of iso-caloric diets containing varying amounts of pulses using Hybrid-LCA and Combined Nutritional and Environmental-LCA (CONE-LCA); and 3) to estimate environmental impact of increased demand for pulses using consequential LCA. Scope of the study varied for each objective with system boundary encompassing cradle-to-grave activities for objective 1 …

Chromosome Number Evolution, Phylogeography, And The Effects Of Climate Change On Species Distributions In Polyploid Plant Systems, Courtney H. Babin

University of New Orleans Theses and Dissertations

Polyploidy, a term used to describe organisms with cells having more than two paired sets of chromosomes, is a significant driver of diversification among land plants. Over a century of research has advanced our understanding of polyploidization in some taxa, but polyploid organisms remain understudied. In this dissertation, I investigate chromosome number evolution, phylogeographic structure, genetic differentiation, and the effects of climate change on ploidy level distribution using polyploid plant systems. In the first chapter, I inferred a molecular phylogeny of Allium, an economically important genus that includes cultivated crops and ornamentals, to investigate evolutionary transitions in chromosome number …

Application Of A 14c-Assay To Assess Methanotrophic Biodegradation Of Tce In Low Ph Groundwater, Evan Groome

All Theses

Current biological strategies for remediating trichloroethylene (TCE) in low pH aquifers (i.e., pH14C-TCE assay was developed to determine pseudo first-order rate constants for the degradation of TCE in microcosms containing soil and groundwater from the Boeing Michigan Aeronautical Research Center (BOMARC) superfund site, where the pH ranges from 4.1 to 4.9. The ¹⁴C-TCE assay was also adapted to calculate soil-normalized rate constants for data from this site, as well as data that Szwast²¹ collected from the Beltsville Agricultural Research Center (BARC). In addition to natural attenuation, biostimulation through amendments of methane and nutrients were also assessed. This treatment …

Developing A Miniature Smart Boat For Marine Research, Michael Isaac Eirinberg

Computer Engineering

This project examines the development of a smart boat which could serve as a possible marine research apparatus. The smart boat consists of a miniature vessel containing a low-cost microcontroller to live stream a camera feed, GPS telemetry, and compass data through its own WiFi access point. The smart boat also has the potential for autonomous navigation. My project captivated the interest of several members of California Polytechnic State University, San Luis Obispo’s (Cal Poly SLO) Marine Science Department faculty, who proposed a variety of fascinating and valuable smart boat applications.

Identifying Key Stream Restoration Variables In An Agriculturally Impaired Chesapeake Bay Watershed, Julia Portmann

Masters Theses, 2020-current

The Chesapeake Bay watershed spans several states, supports diverse ecosystems, and is crucial to local economies. However, agricultural practices in this region impair water quality. The Smith Creek watershed, within the Shenandoah Valley, was designated a showcase watershed in 2010 by the United States Department of Agriculture to demonstrate the efficacy of implementing restoration projects. We sampled fifteen farms ranging from unrestored to thirty-six years since restoration. At each site, we conducted a kick-net survey for macroinvertebrates, measured canopy cover, algal density, substrate size, and bank height and angle. We identified macroinvertebrates to family and calculated the Chesapeake Basin-wide Index …

The Effect Of Different Feeding Regimes On Recent Nutritional And Growth Measurements In Juvenile California Killifish (Fundulus Parvipinnis), Emily Parks

Theses

Gaining a deeper understanding of in-situ growth approximations for juvenile fishes is one way to understand how food consumption may affect fish growth. If variations in growth rate are strongly mirrored by past food status, then the condition (degree of well-being) of fish can be potentially used as a reference for relative prey availability. Furthermore, confirming that there is a positive relationship between food availability and fish growth rate is a critical first step to deepen our understanding of growth rate variation as well as examining if growth can be a proxy for habitat quality.

The California killifish (Fundulus …

The Effects Of Dissolved And Suspended Solids On Freshwater Meiofauna, Jessica Cline

Honors Theses

Meiofauna include small-sized animals (< 1mm) distributed in all aquatic ecosystems on Earth, where they play fundamental trophic and ecological roles. The biodiversity of marine meiofauna and its links with anthropogenic activities is routinely investigated, however, freshwater communities are less known. This is particularly true for the Southeastern United States, which is greatly investigated and elected a hotspot of biodiversity for larger species but very little is known about the meiofauna. The purpose of this research is to reveal the biodiversity of meiofauna from the Tennessee River and test for potential correlations with anthropogenic activities. As a proxy for pollution, dissolved and suspended solids were considered in this study. The research hypothesis is that meiofaunal biodiversity would be affected by possible changes of dissolved and suspended solids in the water column. Possible mechanisms causing biodiversity shifts could be ascribed to osmotic stresses of animals to cope with variation in dissolved solids or, more indirectly, because different sunlight penetration caused by suspended solids would affect primary production. To test the hypothesis, water samples were collected from nine stations located along the Tennessee River in Hamilton County. Each station was visited three times, and, during each visit, environmental parameters (including dissolved and suspended solids) were measured. Meiofauna biodiversity (estimated as richness, community composition, and phylogenetic diversity) was revealed using a metagenomic approach. Statistical analyses were applied to test for possible correlations between the biodiversity estimates and the measured environmental parameters. Results show a high biodiversity of meiofauna with more than 200 amplicon-sequence variants distributed across 10 metazoan phyla. Environmental conditions are highly variable among stations and statistical analyses show that while both dissolved solids (TDS) and turbidity (suspended solids, NTU) did not significantly affect meiofauna biodiversity in the collected samples, various other water, and sediment metrics were found to be significant predictors of meiofauna biodiversity. In conclusion, the results of this project not only reveal for the first time the meiofauna biodiversity from the Tennessee River, but also suggest that meiofauna could be used as bioindicators for several anthropogenic activities in freshwater ecosystems.

Rodent Dental Microwear Texture Analysis As A Proxy For Fine-Scale Paleoenvironment Reconstruction, Jenny H. E. Burgman

Graduate Theses and Dissertations

Dental microwear texture analysis (DMTA) of fossil fauna has become a valuable tool for dietary inference and paleoenvironment reconstruction. Most of this work has utilized larger taxa with larger home ranges. These studies may result in broader-scale habitat inferences that could mask the details of complex mosaic habitats. Rodent DMTA offers an opportunity to work at finer spatial scales because most species have smaller home ranges. Rodents are also keystone species within their ecosystems, abundant, ubiquitous, and found in many fossil deposits. These attributes make them excellent proxies for environmental reconstructions. However, the application of DMTA to rodents remains relatively …

In The Face Of Climate Change, Does Human Trampling Affect Dune Resilience And Alter Ecosystem Services?, Alexandra O. Findlay

Honors College Theses

Sand dunes play a valuable role on the coastline supporting unique native species and protecting beach communities. The City of Tybee Island, Georgia, USA has undergone extensive dune restoration to expand and rehabilitate its shoreline to better defend the town against the increasing frequency of hurricanes and storm surge. The project included the recovery of existing dune structures and construction of new dunes filled with sand pumped from offshore and vegetated with a variety of native species. To analyze the impact of human trampling on dune vegetation occurring adjacent to footpaths and crossovers in new and established dunes, we measured …

Superfund And Society Benumbed: An In-Depth Look At Environmental Justice In South Carolina, Sydney A. Hampton

Senior Theses

This thesis investigates the relationship between superfund sites in minority communities and their public health through the lens of social vulnerability. Various demographic parameters were used to assess the risk associated with minority communities and exposure to hazardous waste. After investigating the history of the Environmental Justice movement, three superfund sites of interest in South Carolina, and demographic and public health data; each community was analyzed to determine association between exposure to hazardous waste and minority status. Each examined community exhibited characteristics contributing to heightened social vulnerability, potentially causing increased susceptibility to negative health outcomes from exposure to hazardous waste.

A Comparison Of Natural, Living, And Hardened Shorelines Ability To Prevent Coastal Erosion And Maintain A Healthy Ecosystem, Gabrielle Spellmann

Master's Theses

It is important to find a suitable method to protect the U.S. Gulf Coast shoreline, since its’ low elevation and the Loop current make it vulnerable to sea level rise. I focused on two manmade methods, hardened, and living shorelines, of coastal protection for when the natural marsh suffers excess erosion rates. Living shorelines are a suite of shoreline conservation and restoration techniques that usually involve some sort of hardened structure that dampens wave energy so that the native vegetation behind it can take root and stabilize the shoreline. This study looked at six different sites, all containing a natural, …

Drought Responses Across Diverse Conifer Species, Habitats, And Competitive Gradients In Northern California, Gabriel J. Roletti

Cal Poly Humboldt theses and projects

Frequent and intense drought events are rapidly altering stand dynamics in western North American forests. Climate, competition, and site characteristics can affect the growth responses of individual trees to drought stress. The ecological and geographical diversity of northern California provides a unique opportunity to measure these responses across species, habitat types, and levels of competitive pressure. This study used dendrochronological techniques and linear mixed-effects models to assess growth responses to drought in four montane and two coastal conifer species across 54 study sites (nine sites per species and 540 trees total) in northern California. Growth was evaluated from 2002-2018 and …

Low-Head Dam Removal Increases Functional Diversity Of Stream Fish Assemblages, Adam Christopher Jones

Masters Theses

Despite the growing number of dam removals to date, very few have been studied to understand their impacts on stream fish communities. Despite being the most common type of dam in the U.S., an even smaller proportion of studies focus on the impacts of low-head dam removals, instead, focusing on the impacts of removal of larger dams. In this study, two previously impounded Illinois rivers were monitored to assess the impacts of low-head dam removal on the functional assemblage of stream fishes. This was accomplished by aggregating fishes into habitat and reproductive guilds, relating community changes to habitat, environmental metrics, …