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Fire History, Ecological History, And Historical Human-Environment Interactions In The Northern Great Plains, James Victor Benes

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation explores the spatiotemporal signatures of fire in North American grassland ecosystems. In three chapters, I explore different aspects of fire history in the northern Great Plains. Chapter 1 is an introduction. Chapter 2 focuses on the Euro-American Settlement Period (ca. 1850–1950 C.E.). Fire histories from six different lakes in the Nebraska Sandhills are compared with two periods of historic drought and the establishment of United States Post Offices. Five of the six records show increased levels of biomass burning during the initial phases of Euro-American Settlement. Chapter 3 is a long-term (ca. 15,000 years), high-resolution fire history and …

El Maíz Del Abuelo: Fidel Márquez Sanchez’S Legacy And Mexico’S Historical Maize Agriculture, Lucia Marquez-Uppman

Scripps Senior Theses

The Green Revolution was an era of scientific development in productive agricultural methods and technologies in the mid-twentieth century. High-yielding seed varieties, artificial fertilizers, irrigation infrastructure, pesticides, and herbicides all developed from this period. Texcoco, Mexico was the center of much of the Green Revolution's education and research from the 1940s onward at the Autonomous University of Chapingo, a prestigious agricultural school, with funding from the US-based philanthropic Rockefeller Foundation. Powerful consequences in the globe's agriculture emerged from the Green Revolution, including the production of maize, a staple crop in Mexico, especially for Indigenous and campesino populations. My abuelo, Fidel …

The Signal Of Airplane Combustion In Soil At A Small Airport In Ohio, Rachel Engels

Williams Honors College, Honors Research Projects

Leaded gas has been banned for automobile use in the interest of public health since 1996. However, leaded gas is still used for small piston aircraft so the engine can run safely. To investigate potential environmental impacts of leaded gas, 90 soil samples were taken from around a small airport in Ohio. Soil elemental composition was measured by X-ray fluorescence (XRF), soil organic content determined by Loss-on-Ignition (LOI), and soil ferrimagnetic content measured by magnetic susceptibility. There is an unmistakable airplane fuel combustion signal in the soil at the ends of the runway, where aircraft wait to take off on …

Fabrication Of Thylakoid Membrane-Based Photo-Bioelectrochemical Bioanode For Self-Powered Light-Driven Electronics, Amit Sarode, Gymama Slaughter

Center for Bioelectronics Publications

The transition toward sustainable and decentralized energy solutions necessitates the development of innovative bioelectronic systems capable of harvesting and converting renewable energy. Here, we present a novel photo-bioelectrochemical fuel cell architecture based on a biohybrid anode integrating laser-induced graphene (LIG), poly(3,4-ethylenedioxythiophene) (PEDOT), and isolated thylakoid membranes. LIG provided a porous, conductive scaffold, while PEDOT enhanced electrode compatibility, electrical conductivity, and operational stability. Compared to MXene-based systems that involve complex, multi-step synthesis, PEDOT offers a cost-effective and scalable alternative for bioelectrode fabrication. Thylakoid membranes were immobilized onto the PEDOT-modified LIG surface to enable light-driven electron generation. Electrochemical characterization revealed enhanced redox …

An Analysis Of Coal Ash Pollution In The State Of Georgia, Mick W. Etchison

Theses and Dissertations

This social science paper will explore the factors contributing to the prevalence of coal ash in specific regions of Georgia and its impact on local ecosystems and human health. It provides an analysis of the current environmental and political issues surrounding the containment and spread of coal ash throughout the State. Coal ash is primarily found in the central, southwestern, and northeastern regions where coal-fired power plants and coal ash storage sites are located. The paper will then discuss the political, economic, and legal reasons behind the lack of effective regulation and mitigation of coal ash spread. Coal ash illustrates …

From Lawns To Life: Landscaping For Biodiversity On Mason’S Island, Margit Burgess

Open Access Master's Theses

The collapse of biodiversity is an existential threat to life on Earth. Residential landscapes, dominated by open lawns maintained in turfgrass, do not support biodiversity. In the United States, turfgrass has replaced native landscapes in over 40 million acres, with 500 square miles added each year (Tallamy, 2019). Of the 78% of the U.S. land that is privately owned, approximately 135 million acres - nearly twice the size of all national parks combined - are residential (Milesi et al., 2005). With a shift in private landscape management, this land could present a largely untapped opportunity for biodiversity restoration and social …

Micro- And Nano-Plastics Preparation And Their Impact On Cobetia Marina, Lauren Lamothe

Open Access Master's Theses

Plastic pollution has become an increasing threat to marine and coastal environments. Macroplastics derived from consumer waste are broken down by chemical and physical degradation processes, resulting in micro- and nano-plastics (MPs and NPs). This thesis presents an investigation into the MP and NP pollution in the sea surface microlayer (SSML). The SSML contains surface active compounds and natural and anthropogenic matter. This study provides insight into the deeper impacts on the transport and fate of MPs and NPs and on marine bacteria. The first chapter works through the breakdown of plastic particles with the use of a top-down approach …

Investigating The Effectiveness Of Best Management Practices In Reducing Fecal Bacteria In Narrow River, Rhode Island, Katherine Thompson

Open Access Master's Theses

Fecal bacterial contamination shapes how communities manage and use estuarine waters, with consequences for ecosystem health and public access. In Rhode Island's Narrow River, elevated concentrations of fecal coliforms and enterococci have restricted shellfishing for decades despite ongoing management efforts. From 2004 to 2018, local organizations implemented Best Management Practices (BMPs) to address water quality challenges, yet their effectiveness remains incompletely understood. This study analyzes three decades of monitoring data using linear regression, generalized additive models, and Before After Control Impact methods to evaluate BMP effectiveness and identify key drivers of contamination. Linear regression revealed spatially variable trends, with bacterial …

Plastics And Their Interactions With Bacterial Biofilms Of Synechococcus Sp. Pcc 7002 And Escherichia Coli Nissle 1917, Jackson Zmich

Open Access Master's Theses

Plastic waste is a leading global pollutant with increasing concerns, as recent studies have shown that these wastes are not only concentrated on a macro scale but on a micro and nano scale. These micro- and nano- sized plastic particles, denoted as MPs and NPs, have been measured in marine and freshwater sources, air, food products, and within biosolids expelled from organisms, including humans. Due to their small size, MNPs are entering organisms through inhalation, ingestion, or dermal absorption. [1] Humans are ingesting MNPs daily, with median rates of approximately 200 ng/capita/day for children and 600 ng/capita/day for adults. [2] …

Spectrum Of The Lakes: Using Satellite Remote Sensing To Unveil Water Color In Minnesota's Sentinel Lakes For Water Quality Monitoring, Andrew J. Dooley, Wondwosen M. Seyoum, Catherine M. O'Reilly

Faculty Publications - Geography, Geology, and the Environment

Traditional water quality monitoring methods often face limitations of equipment costs and labor demands, requiring innovative approaches to effectively assess the ecological health of inland lakes across vast areas. This research explores the application of free, publicly available water color chromaticity analysis for midcontinent lakes in Minnesota, USA. We examined water color variations in Minnesota’s Sentinel Lakes using Landsat 8 OLI data to analyze surface reflectance samples collected from the deepest area within each lake during the late summer, corresponding to peak annual insolation and trophic activity. The median dominant visible wavelength was used to characterize water color. Results indicate …

Computational Assessment Of Vitrimers Self-Healing For Renewable Energy And Aerospace Structures, Walaaeldin Mohamed Ahmed Derbala

Browse all Theses and Dissertations

Self-healing polymers, particularly vitrimers, are emerging as promising candidates in the development of advanced materials for renewable energy and aerospace structures. These materials exhibit dynamic covalent bond exchange mechanisms that enable reprocess ability, damage repair, and extended operational lifetime under harsh conditions. This study presents a density functional theory (DFT)-based computational investigation of the mechanistic pathways and energetics of bond exchange reactions in model vitrimer systems. We explore transition states, energy barriers, and thermodynamic features corresponding to associative and dissociative self-healing reactions in vitrimers. The study focuses on Diaminodiphenyl disulfide (AFD), a bifunctional molecule composed of two para-substituted aminophenyl rings …

Assessing Arbuscular Mycorrhizal Fungal Community Composition And Diversity Across A Land-Use Gradient In Eastern Washington Prairies, Katherine I. Cole

EWU Masters Thesis Collection

Arbuscular mycorrhizal fungi (AMF) are key to healthy, functioning terrestrial ecosystems worldwide. Associating with over 80% of all extant land plants, they play a pivotal role in nutrient cycling, and contribute to overall plant health. Given their significance to terrestrial ecosystems, AMF have a crucial role to play in the successful restoration of Eastern Washington’s native prairies. However, AMF community composition is significantly altered by the commercial agricultural practices used extensively in this region for over 100 years. The Eastern Washington University (EWU) Prairie Restoration Project aims to restore ~120 acres of farmland to native prairie. This research provides insight …

Growth, Survival, And Herbivore Browsing Preferences Of Seedlings Planted In Black Ash Stands Of Northern Michigan And Wisconsin, Seth W. Davenport

Dissertations, Master's Theses and Master's Reports

To mitigate the cascading ecosystem impacts of widespread black ash (Fraxinus nigra) mortality due to the invasive emerald ash borer (Agrilus planipennis), forested wetlands can be underplanted with seedlings of alternative species that later repopulate the vacated canopy. This study examined the survival and growth, factors influencing performance, and herbivore browsing preferences of seven non-ash species planted in northern Michigan and Wisconsin. The best performing species were river birch (Betula nigra), silver maple (Acer saccharinum), and swamp white oak (Quercus bicolor). The worst performing species was black spruce (Picea …

Development Of A Scituate Reservoir Mitigation Model For Assessing Flood Control During Extreme Scenarios, Supria Paul

Open Access Dissertations

Effective reservoir management is essential for mitigating downstream flooding, especially with the increasing frequency and intensity of extreme weather events impacting major drinking water reservoirs such as the Scituate Reservoir in Rhode Island. These reservoirs provide water for large populations but can be overwhelmed by intense precipitation, flooding and land cover changes. Climate change is expected to increase precipitation in the study area located in New England, highlighting the need for improved reservoir systems, especially given the aging dams and higher risk of failures. Additionally, land cover changes, like the widespread defoliation caused by the Gypsy Moth infestations, affect water …

A Critical Juncture: The Convergence Of Natural Resource Management And Tribal Sovereignty, Anna Aleta Butterfield

Graduate Student Portfolios, Professional Papers, and Capstone Projects

This portfolio reflects the work I’ve done in my four years as a dual degree student, pursuing a Master of Science in Environmental Studies and a juris doctorate degree, and focuses on policies and laws surrounding natural resource management. It touches on how those policies relate to and expand or constrict the exercise of sovereignty by indigenous populations.

This piece first considers the effects of plastic on salmon populations and those indigenous groups that rely on salmon for subsistence and cultural purposes. The remaining three pieces focus on various aspects of the Confederated Salish and Kootenai Tribes - Montana Water …

Integrated Pest Management: State Infrastructure Status After 50 Yr Of Federal Support (1973 To 2023), Daren S. Mueller, Laura C. Iles, Carol L. Pilcher, Adam J. Sisson, Roger Magarey, Ryan Adams, Wanda I. Almodovar, Diane Alston, Patrick Beauzay, Ricardo Bessin, Mandy Bish, Mary Burrows, Alejandro Calixto, Rakesh Chandran, Jed B. Colquhoun, Mary Concklin, Amy J. Dreves, Peter C. Ellsworth, Paul D. Esker, James J. Farrar, Alfred Fournier, Daniel Frank, Kelly Hamby, George Hamilton, Anthony Hanson, Ann Hazelrigg, Natalie Hein-Ferris, David Held, James Jasinski, Heather M. Kelly, David Kerns, Miranda Kersten, Lauren Kerzicnik, Janet Knodel, Glen Koehler, Heidi Kratsch, Christian H. Krupke, Norman C. Leppla, Erin Lizotte, Casey Matney, Rebecca A. Melanson, Frannie Miller, Marion Murray, David Owens, Diane Plewa, Francis P. F. Reay-Jones, Silvia I. Rondon, Tom A. Royer, Philip A. Rozeboom, Hilary A. Sandler, Scott P. Schell, Marissa Schuh, Timothy Seipel, Danesha Seth Carley, Ashfaq Sial, Raghuwinder Singh, Damon L. Smith, Tim Stock, Glenn Studebaker, Adrianna Szczepaniec, Lisa Tewksbury, John Tooker, Adam J. Varenhorst, Amber Vinchesi-Vahl, Doug Walsh, Desiree Wickwar, Robert J, Wright, Simon Zebelo

Department of Entomology: Faculty Publications

Integrated pest management uses a variety of tools coupled with historical, current, and projected information for economical pest protection of crops and other resources while accounting for risk to humans and the environment. Following the 1972 US Federal IPM Policy, funding for integrated pest management programming has continued for 50+ years. However, multifaceted changes during this time have significantly affected state-level integrated pest management infrastructure, prompting a comprehensive survey to assess conditions, limitations, and growth potential of US integrated pest management programs. A survey was sent to 50 US states and 3 territories with integrated pest management programs in November …

Crop2cloud Platform: Real-Time Data Integration For Agricultural Water Monitoring, Bryan Nsoh, Abia Katimbo, Kendall Dejonge, Wei-Zhen Liang, Hongzhi N. Guo, Yufeng Ge, Derek M. Heeren, Yeyin Shi, Xin Qiao, Daran R. Rudnick, Hope Njuki Nakabuye, Birru Girma, Isa Kabenge, Joshua Wanyama

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Efficient water management is vital for sustainable agriculture, yet integrating real-time data for precise irrigation remains a challenge. This study designed the Crop2Cloud (C2C) platform, a system that leverages advanced sensors using Internet of Things (IoT), edge and cloud computing techniques, and computed Water Stress Indices (WSIs) and machine learning models (i.e., fuzzy logic), to provide scalable and real-time irrigation decisions. The C2C platform aggregates several data including Volumetric Water Content (VWC) from TDR sensors (Acclima Inc., US) installed at four multiple depths, canopy temperatures (Tc) measured by Infrared Radiometers (IRTs) (Apogee Instruments, US), as well as weather information and …

Synthesis And Characterization Of Eco-Engineered Hollow Fe2o3/Carbon Nanocomposite Spheres: Evaluating Structural, Optical, Antibacterial, And Lead Adsorption Properties, Islam Gomaa

Nanotechnology Research Centre

This work presents a facile mechano-thermal route for the synthesis of carbon-decorated, hollow, mesoporous α-Fe2O3 microspheres. Comprehensive characterization (XRD, XPS, FT-IR, SEM/EDX, TGA, zeta-potential) confirmed the formation of phase-pure hematite with nanoscale crystallites (~19 nm), substantial residual surface carbon (~40 wt%) consistent with Fe–O–C linkages, and a positive surface charge (+15.9 mV). The hierarchical hollow/mesoporous architecture enables fast ion transport and provides extensive interior binding sites, resulting in rapid Pb(II) uptake that reaches 92% removal in ≈15 min at pH 5.0. The adsorption follows a Langmuir isotherm (qmax ≈ 70.6 mg/g) and pseudo-second-order kinetics, indicative of chemisorption coupled to efficient …

Cover Crops Can Reduce Greenhouse Gas Emissions From No-Till Maize In Southern Brazil: Insights From A Long-Term Field Experiment, Guilherme Rosa Da Silva, Adam J. Liska, Cimélio Bayer

Adam Liska Papers

Brazil is one of the countries that has the most agricultural area under no-till (NT) management. This research study aims to evaluate life-cycle greenhouse gas (GHG) emissions from maize (M) grain production in agroecosystems that used different cover crops under NT management in southern Brazil. The data for this study were from a long-term 41-year field experiment in southern Brazil. The long-term experiment evaluated the effects of fallow (F) and cover crops (oat (O), vetch (V), cowpea (B), pigeon pea (P), and lablab (L)) on nitrous oxide and methane emissions and soil carbon (C) sequestration in maize agroecosystems. Five cropping …

Microbial Community Stabilization By Restored Oyster Reefs: Implications For Blue Carbon Storage, Natalie Boydstun

College of Graduate Studies: Theses & Dissertations

Coastal ecosystems provide critical carbon sequestration services, yet the microbial mechanisms underlying carbon storage remain poorly understood, particularly in non-vegetated habitats. This study investigated whether restored oyster reefs (Crassostrea virginica) enhance sediment carbon storage potential by stabilizing microbial communities and promoting efficient organic matter processing. I hypothesized that reef-mediated sediment stabilization and organic deposition would create conditions favoring microbial degradation of complex carbon compounds into stable soil organic matter, ultimately supporting anaerobic carbon storage. To test this, I compared sediment biogeochemistry, enzyme activity, and microbial community structure between three restored oyster reef sites and two unstructured control sites …

Identifying The Impacts Of Land Use/Land Cover Changes On Ecosystem Services From A Geospatial Perspective In Albany County, Kyaw Khaung Thant Zin

Electronic Theses & Dissertations (2024 - present)

Ecosystem services encompass the broad array of direct and indirect advantages that people derive from nature and its ecosystems. Considering accelerating environmental change and degradation, recognizing the importance of these services is more crucial than ever, as they illustrate the many ways in which healthy ecosystems sustain human life. However, these services are diminishing at a rapid and unprecedented rate, raising global concern over both the transformations taking place and their root causes. Among the leading threats, land-use change stands out as a particularly significant one, influenced by a variety of driving factors. Albany County, New York, characterized by its …

Theoretical Foundations And Applied Performance Of Periodicity-Aware Imputation: Variable Bandpass Block Bootstrap Methods For Incomplete Time Series, Asmaa Ahmad

Electronic Theses & Dissertations (2024 - present)

Time series data are prevalent across a wide range of disciplines, including health surveillance, public policy, and environmental monitoring. In the presence of underlying cyclical patterns, the integrity of time series analysis depends critically on the ability to detect, model, and impute structured missing data without compromising the temporal structure. This dissertation introduces and validates a novel imputation framework that integrates the Variable Bandpass Periodic Block Bootstrap (VBPBB) into multiple imputation procedures, improving the accuracy, robustness, and interpretability of time series models under high rates of missingness and noise. The overarching goal of this dissertation was to develop and evaluate …

The Coral Porites Lutea As A Regional And Local Proxy For Sea Surface Temperature In Hong Kong, And The Effects Of Typhoons On Proxy Accuracy, Brenna E. Bell

CMC Senior Theses

Proxies related to the climate have been used as a method to observe long-term changes occurring underwater that span long before we had the capability to measure environmental characteristics. Porites corals have been used as sea surface temperature (SST) proxies due to annual cyclicity in their growth process and mineral composition. As the climate differs globally, it is important to ensure that proxies are accurate regardless of location to measure changes in climate. This study examines Porites lutea corals as an SST proxy in the region of Hong Kong. Potential local differences in SST proxy calibrations within the surrounding waters …

Movement And Activity Of Burbot, (Mizay; Lota Lota) In A Spring-Fed Minnesota Lake, Abigail M. Fountain

Biology Graduate Theses

Burbot (Mizay; Lota lota) are a relatively unmanaged freshwater fish, important in many local Indigenous cultures, but often overlooked or maltreated in research, conservation, and fishing practices. As such, relatively little research has been conducted on Burbot, despite ecological significance as an indicator species. A recent resurgence in popularity as a target species, however, has prompted new research to inform management policies. The objectives of this study were to summarize Burbot movement by identifying patterns in swimming activity and identify possible predictors of the movement observed. This study investigated the movements of 39 individuals implanted with acoustic transmitters in Bad …

Sptiotemporal Changes In Aboveground Biomass, Canopy Cover And Livestock Movements Across Mongolia Grasslands, Abhinav Chandel

Dissertations and Theses

This study presents an integrated geospatial framework for understanding grassland productivity dynamics and livestock movement behavior across the Mongolian steppe. Mongolia’s grasslands constitute one of the world’s largest pastoral ecosystems, yet they face increasing vulnerability due to climate variability, overgrazing, and land degradation. To quantify vegetation change and grazing responses, this research combines multi-decadal remote sensing with high-frequency GPS-based livestock movement tracking. Using Landsat imagery from 1990 to 2023, Aboveground Biomass (AGB) and Canopy Cover (CC) were estimated through Random Forest regression models integrating key spectral vegetation indices (e.g., NDVI, OSAVI, CTVI, TNDVI, IPVI) and climatic predictors such as summer …

Estimating The Amount Of Carbon Dioxide Gas Removed From The Atmosphere By The Bryant Park Tree Population, Edimarlyn Gonzalez

Open Educational Resources

No abstract provided.

Community-Wide Impacts Assessment Of Silver Carp (Hypophthalmichthys Molitrix) In The Ohio River, Luka Marques

Graduate Theses, Dissertations, and Problem Reports (ETD)

Invasive species can cause measurable impacts on the properties of recipient ecosystems, with effects that often vary spatially and temporally. One of the most complex and pressing invasion cases in the United States involves invasive carp. Invasive carp have quickly expanded throughout the Mississippi River Basin, with ecological impacts that may vary across space and time. Silver Carp has the potential to provoke community-wide impacts on native fish abundances and food webs of native fish communities. My study area ranged from the confluence of the Mississippi River and the Ohio River to R.C. Byrd Lock and Dam. The Ohio River …

A Collaborative Assessment Of Coastal Ocean Acidification Monitoring In Maine & Standard Operating Procedures And Best Practices For The Collection Of Continuous Ph Data In Coastal Marine Environments, Christopher W. Hunt, Curtis Bohlen, Mike Doan, Jeremy Miller

Faculty Publications

The ‘Sensor Squad’ of the Maine Ocean Climate Collaborative is the product of a 2023 Maine Coastal and Marine Climate Action Fund grant to conduct “A two-year pilot project designed to address and overcome technological barriers to ocean acidification data collection, develop protocols to elevate quality assurance and ensure comparable data, and meet regularly to discuss project results and data compilation”. The Squad consists of representatives from Friends of Casco Bay (FOCB), Wells National Estuarine Research Reserve (WNERR), and the University of New Hampshire (UNH). This report is a summary of their efforts to assess affordable, repeatable means of continuously …

How To Be A Nature Detective (1966) By Millicent E. Selsam, Maughn Rollins Gregory

Picture Books

Coming up with the most reasonable explanation of the available clues is something we all do on a daily basis. This book describes animal tracks as clues from which children can make inferences about what kind of animal left them and what they were doing when they did.

Meteorology, Weather And War In South East Asia: Malaya C. 1940-1960, Fiona Williamson

Research Collection College of Integrative Studies

This article interrogates the positioning of British colonial meteorology in Malaysia and Singapore from the 1940s to 1960. This period spanned a global conflict and an internecine war, effecting profound sociopolitical changes from which neither Malaysia nor Singapore would emerge the same. The meteorological services were essential to Britain's armed conflicts, providing vital weather information to the army, navy and, especially, the air forces, as well as supporting the aviation and shipping industry often in difficult and dangerous circumstances. This article argues that British military policy in South East Asia and the specific concerns of the colonial government in Malaya …