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Investigating The Thermal Stratification Patterns Of A Shallow Polymictic Boreal Shield Lake And The Effectiveness Of Models In Predicting Shallow Lake Thermal Profiles, Matthew Roberts

Theses and Dissertations (Comprehensive)

Thermal stratification is a core process of lakes which plays a critical role in shaping the ecological dynamics of lakes, influencing major processes like nutrient cycling and oxygen availability. For shallow polymictic lakes, thermal stratification patterns present some unique differences due to the complex and variable nature of these lakes. In this thesis, I examined thermal stratification in a shallow polymictic lake in northwestern Ontario during the ice-free season of 2019 to investigate the frequency, duration, and driving factors of thermal stratification. The lake underwent 146 separate stratification events, with a median duration of 2 hours per event, with a …

Using Landscape Ecology And Spatial Statistics To Examine The Impacts Of Proposed Removals To Natural Heritage System And The Agricultural System Of Ontario’S Greenbelt, Brianna Downey

Theses and Dissertations (Comprehensive)

The 2022 proposed removals from the Greater Toronto Area (GTA), Southern Ontario’s Greenbelt would have resulted in negative impacts including, reductions to the size and functionality of the Agricultural System and Natural Heritage System, which are components of protected Greenbelt area. Several removal sites were located either on or in close proximity to corridor areas of the NHS, reducing connectivity and negatively impacting the surrounding ecological area. The removal of Agricultural land primarily consisted of corn and soybeans, as well as large removals of woodland, wetland, and shrubland class areas. The removal sites on local Agricultural composition and configuration were …

Controls Of Wetland Hydrology In The Zone Of Discontinuous Permafrost, Northwest Territories, Canada, Iain Thomson

Theses and Dissertations (Comprehensive)

Mean annual air temperatures are increasing rapidly in northwestern Canada, which is among the most rapidly warming regions on Earth (Box et al., 2019). Consequently, permafrost thaw within northwestern Canada is proceeding at a rate not found in the historical record (Pelletier et al., 2017), with areal thaw rates especially high in the peatland-dominated southern margin of discontinuous permafrost (Quinton et al., 2019). Permafrost thaw has caused vast land cover changes and transformed the permafrost underlain forest into permafrost free wetlands over much of Taiga Plains (Carpino et al., 2018; Jorgenson & Osterkamp, 2005). This land cover change has …

Small Area Estimation Of Forest Biomass Via A Two-Stage Model For Continuous Zero-Inflated Data, Grayson W. White, Josh K. Yamamoto, Dinan H. Elsyad, Julian F. Schmitt, Niels H. Korsgaard, Jie Hu, George C. Gaines Iii, Tracey S. Frescino, Kelly S. Mcconville

Faculty Journal Articles

Nationwide Forest Inventories (NFIs) collect data on and monitor the trends of forests across the globe. Users of NFI data are increasingly interested in monitoring forest attributes such as biomass at fine geographic and temporal scales, resulting in a need for assessment and development of small area estimation techniques in forest inventory. We implement a small area estimator and parametric bootstrap estimator that account for zero-inflation in biomass data via a two-stage model-based approach and compare the performance to a Horvitz–Thompson estimator, a post-stratified estimator, and to the unit- and area-level empirical best linear unbiased prediction (EBLUP) estimators. We conduct …

Operational Risk Evaluation Of Oil Tankers Via Multivariate Gaidai Reliability Framework Incorporating Memory Effects, Oleg Gaidai, Shicheng He, Jinlu Sheng, Yan Zhu, Alaa Elsayed, Mahmoud El-Wazery

Journal of Marine Science and Technology–Taiwan

The retreat of Arctic Sea ice may exert a major impact on economy，potentially transforming the nature of commerce between Asia, Europe, and the Americas. Projections indicate a 40% reduction in transit distance and a 30% decrease in voyage time between Europe and northwest Asia compared to traditional routes such as the Suez Canal. However, even during summer navigation, fragmented floating ice persists, generating stochastic ice loads on vessel bows and hulls through complex ship-to-ice interaction. For structural design, statistical extrapolation methods are required to accurately assess excessive areal bow/hull stresses. This study proposes a novel multi-modal structural damage risk assessment …

In-Situ And Laboratory Sound Velocities Of Unconsolidated Sediments In The Western South Korea Plateau Of The East Sea, Kiju Park, Gil Young Kim, Yuri Kim, Bo Yeon Yi, Nyeon Keon Kang, Gwang Soo Lee

Journal of Marine Science and Technology–Taiwan

The in-situ velocity of unconsolidated shelf sediments in the western South Korea Plateau of the East Sea was directly measured using the Korea Institute of Geoscience and Mineral Resources (KIGAM) Seafloor Acoustic Probe. Physical properties, including laboratory velocity, were also measured for core samples collected from the same location. The laboratory measurements were conducted at a temperature of 23℃ and under atmospheric pressure. Owing to the in-situ temperature and pressure (0.5–1.5℃ and 100–180 atm, respectively) at the sampling site, the laboratory velocity was adjusted to the in-situ conditions. In addition, a comparison with a theoretical prediction model (Biot-Stoll model) was …

Hydrographic Influences On Seasonal Variations In Zooplankton Communities Of Taiwan Bank (Southern Taiwan Strait), Bor-Shyr Chen, Frank Paolo Jay B. Albarico, Mark Ariel D. Malto, Aiza D. Gabriel, Chiu-Wen Chen, Cheng-Di Dong

Journal of Marine Science and Technology–Taiwan

Understanding the factors that control ocean productivity is crucial in fisheries management. Taiwan Bank, located between the Taiwan Strait and the South China Sea, is a highly productive ecosystem due to upwelling events. The total zooplankton community (holozooplankton and merozooplankton), diversity, seasonal changes, and environmental drivers remain unexplored despite its productivity. This study evaluates the seasonal and vertical environmental dynamics in the Taiwan Bank and their impacts on the zooplankton community structure. We collected zooplankton and basic water parameters in March, July, and September 2017 at 5, 25, and 50 meters. We recorded significant seasonal changes in zooplankton composition and …

Substrate Preference And Foraging Behavior Of Two Declining Warblers In Appalachian Shrublands, Samantha Fishman

Theses and Dissertations

Abstract Shrubland and early successional habitats (ESH) support a diversity of wildlife, including many declining songbirds. However, nonnative shrubs increasingly dominate these habitats, potentially altering habitat quality by influencing prey availability. Habitat quality can be assessed by observing foraging behaviors of songbirds and identifying preferred and avoided substrates as well as testing the predictions of optimal foraging theory; specifically that birds will maximize their energy gain relative to the costs. We examined foraging behaviors of Golden-winged Warblers (Vermivora chrysoptera; GWWA) and Chestnut-sided Warblers (Setophaga pensylvanica; CSWA) in ESH on private lands in Virginia with varying amounts …

Climate Migration And Urban Survival: Evidence From Chittagong’S Slums, Mohammad Nur Nobi

Graduate Research Theses & Dissertations

This study examines the impact of climate change on rural-to-urban migration in Chittagong, Bangladesh. Based on a primary survey of 400 respondents across 35 slums in the country's second-largest city, the analysis employs two estimation methods: a multinomial logit model to assess the influence of climate-related factors on migration decisions, and a logit model to evaluate the impact of migration on the living conditions of migrants. The results show that individuals involved in ‘agriculture and daily labor’ are most likely to migrate. Compared to the base category (‘Other Reasons’) for migration, the odds ratios for ‘floods’, ‘droughts’, and ‘better job …

Geology, Paleoecology And Vertebrate Biostratigraphy Of The Hell Creek Formation, Carter County, Montana, Usa, Joshua Collin Mathews

Graduate Research Theses & Dissertations

The Hell Creek Formation of the Northern Great Plains records one of the greatest mass extinction events in Earth’s history, bringing to a close the reign of the dinosaurs at the end of the Cretaceous period. This rock unit comprises one of the most studied geological formations in the world and is one of the few locations on the planet that preserve terrestrial deposits containing ejecta from the bolide impact that slammed into the Yucatan Peninsula 66 million years ago. This profound event in the geologic record has led to numerous studies of paleobiotas, climate change, ecosystem recovery dynamics, and …

Convective Modes Associated With Precipitation Exceeding Postfire Debris Flow Thresholds In The Southwestern United States, Anya M. Aponte Torres

Graduate Research Theses & Dissertations

Postfire debris flows can occur when surface-water runoff dislodges and carries a slurry of loose sediment and vegetation downslope, usually in steep, recently burned terrain. Short-duration, high-intensity rainfall embedded within short or long-duration rainstorms (e.g., thunderstorms and atmospheric rivers) is most commonly associated with this mode of debris-flow initiation. The typical horizontal grid spacings of global numerical weather prediction and general circulation models are too coarse to resolve these convective precipitation features, which poses an obstacle to short-term forecasting and investigating future trends in the frequency, magnitude, and characteristics of debris-flow generating rainfall. For this study, 15-minute precipitation and simulated …

Climate Variability Study For Arid Regions, Faisal Almutairi

Electronic Theses and Dissertations

Water is the primary source for all living species to thrive, and water scarcity has been a primary concern for biological species and plants in arid regions due to urban planning, population growth, poor water management, and overgrazing. The objective of this research was to study the climate variability in precipitation and temperature for an arid region. This research encompasses two distinct studies. The first study examined the impact of climate variability on precipitation in Phoenix. Precipitation data were acquired from NOAA from 1948 to 2023 and the study was broken down into three time scales: annually, seasonally, and monthly. …

Shifting Waters: A 41-Year Time-Series Analysis Of Surface Water Change In The Prairie Pothole Region, Madison Dejarlais

Electronic Theses and Dissertations

The Prairie Pothole Region (PRR) is a landscape defined by a dynamic surface water system, with wetlands, lakes, and rivers playing critical roles in supporting biodiversity, regulating floods, and maintaining hydrological balance. This study conducts a time-series analysis of surface water change in the PPR from 1984 to 2024, using remote sensing tools including Google Earth Engine, ArcGIS Pro, and ENVI. 41 annual surface water presence rasters were compiled into a cumulative dataset, allowing for both year-to-year comparisons and broader trend analysis. Results indicate that the presence of surface water in the PPR has not followed a simple linear trend. …

Bridging The Gap Between Plot-Level And Landscape-Scale Analysis For Wildfire Risk Assessment, Vanessa Leigh Niemczyk

Graduate Student Theses, Dissertations, & Professional Papers

Remote sensing technology has advanced greatly over the past couple of decades proving its ability to aid in wildfire risk assessment and improve our understanding of forest structure and fuel inventory across the landscape. While some aerial and satellite sensors perform better than others, they all have a common weakness, their reduced ability to capture understory fuels with high detail. Terrestrial laser scanning is an emerging solution due to its understory perspective. This research leverages the beneficial aspects of both terrestrial laser scanning and various aerial- or satellite-based remote sensing platforms (aerial laser scanning, digital aerial photogrammetry, and Sentinel-2) to …

Bibliometric And Visualisation Analysis Of Biomass Burning Research In Thailand (1997-2024), Weerachon Sawangproh, Arika Bridhikitti

Applied Environmental Research

Biomass burning is a major driver of air pollution and climate-related impacts in Thailand, but a national-level synthesis of research efforts is lacking. This study conducts a comprehensive bibliometric and qualitative review of 256 peer-reviewed publications from 1997–2024, using Scopus-indexeddata to explore research trends, thematic patterns, and existing gaps. The analysis reveals a strong emphasis on atmospheric chemistry, air quality modeling, and remote sensing, which collectively account for more than 60% of the research landscape.Studies frequently focus on pollutants such as PM2.5,PAHs, carbon monoxide, and heavy metals, with biomass burning identified as a dominant source, especiallyduring the dry season in …

Investigating Spatial And Temporal Changes In Vegetation Via Remote Sensing Indicators And Revealing Their Trends In The Central Desert Of Iran, Peyman Akbarzadeh, Shima Nikoo, Mehran Akbarzadeh

Applied Environmental Research

Vegetation changes can significantly affect the conditions and productivity of ecosystems. Consequently, studying vegetation dynamics across various temporal and spatial scales has emerged as a critical environmental concern. The aim of this study was to investigate changes in vegetation cover via vegetation indices, including the normalized difference vegetation index (NDVI), ratio vegetation index (RVI), soil adjusted vegetation index (SAVI), and difference vegetation index (DVI), derived from multitemporal Landsat 5, 7, and 8 satellite images processed via the Google Earth Engine. The study area is located in the Damghan arid and desert watershed, which represents the central desert of Iran. Furthermore, …

Assessment Of The Carbon Stock Of Trees In Selected Urban Green Spaces Of Davao City, Philippines, Daiseree Cuabo, Yves P.M. Montero, Daryl S. Salas, John P.M. Viernes

Applied Environmental Research

The combined impacts of deforestation, tree cover loss, and urbanization in urban and suburban areas significantly reduce the capacity of natural carbon sinks to sequester and store carbon. Hence, this study assessed the aboveground biomass (AGB) and carbon stock of trees in the selected green spaces of Davao City. A purposive sampling technique was employed in placing quadrats, with data collected from 27 plots categorized by size. AGB was estimated via an allometric equation, and aboveground carbon (AGC) was derived from the AGB values. A total of 358 individual trees from 25 species, 24 genera, and 13 families were documented. …

Episodes In Computing History - Salon Talk, George K. Thiruvathukal

Computer Science: Faculty Publications and Other Works

This talk (first given in 2004) presents a concise overview of key developments in the history of computing. It begins with early methods of counting and recordkeeping, such as tally sticks and the Inca quipu. It then traces the evolution of numeric systems, including Roman and Hindu-Arabic notation, and the mathematical contributions of figures like Al-Khwarizmi. Mechanical computing devices such as the abacus, Napier’s bones, and the Pascaline are examined, along with the Jacquard loom and its use of punch cards.

The talk continues through the rise of electronic computing, highlighting milestones such as ENIAC, the work of Alan Turing, …

Differentiating Opioid Use Disorder From Healthy Controls Via Ml Analysis Of Rs-Fmri Networks, Ahmed Temtam, Megan A. Witherow, Liangsuo Ma, M. Shibly Sadique, F. Gerard Moeller, C. Kenneth, Dianne Wright, Khan M. Iftekharuddin

Electrical & Computer Engineering Faculty Publications

Objectives/Goals: This work aims to identify functional brain networks that differentiate opioid use disorder (OUD) subjects from healthy controls (HC) using machine learning (ML) analysis of resting-state fMRI (rs-fMRI). We investigate the default mode network (DMN), salience network (SN), and executive control network (ECN), as well as demographic features. Methods/Study Population: This work uses high-resolution rs-fMRI data from a National Institute on Drug Abuse study (IRB #HM20023630) with 31 OUD and 45 HC subjects. We extract rs-fMRI blood oxygenation level-dependent (BOLD) features from the DMN, SN, and ECN. The Boruta ML algorithm identifies statistically significant features and brain activity mapping …

Computational Bridges: Enhancing Natural Language Processing Of Swahili., Joyce Murungi

Harrisburg University Other Works

Swahili remains significantly underrepresented in natural language processing (NLP) despite being one of the most widely spoken languages in Africa. Computational Bridges: Enhancing Natural Language Processing of Swahili addresses this gap through computational linguistics, corpus creation, and large-scale analysis of Swahili syntax and lexical structure. Central to this study is GUMZO, a novel corpus developed from spontaneous conversational data collected from YouTube videos, television panel discussions, political speeches, religious discourse, and unscripted broadcasts. Unlike many existing datasets that rely on formal or translated text, GUMZO captures authentic language use and provides a stronger foundation for NLP research involving low-resource languages. …

Earth Observations Reveal Impacts Of Climate Variability On Maize Cropping Systems In Sub-Saharan Africa, Adomas Liepa, Michael Thiel, Hannes Taubenböck, Doris Klein, Ingolf Steffan-Dewenter, Marcell K. Peters, Sarah Schönbrodt-Stitt, Insa Otte, Tobias Landmann, Zeyaur R. Khan, Michael Ochieng Obondo, Frank Chidawanyika, Emily A. Martin, Tobias Ullmann

All Peer-Reviewed Publications

In Kenya, climate variability and change threaten smallholder, rainfed farms, with crop failures, yield reductions, and pest infestations. Efficient agroecological strategies, such as Push-Pull intercropping, offer documented benefits including pest control, improved soil fertility, and water conservation compared to traditional maize monocropping. To date, no studies exist comparing traditional maize monocropping and Push-Pull intercropping using earth observation tools over several growing seasons in East Africa. Our research addresses this by harmonizing Landsat 7, 8, 9 with Sentinel-2 remote sensing time series from 2016 to 2023. Phenological metrics of 15 growing seasons are extracted based on a threshold method using the …

Environmental Monitoring Report: For Work Performed: July 1, 2022 Through June 30, 2023, Tennessee. Department Of Environment And Conservation

Environmental Monitoring Reports

This FY2023 EMR presents results for 20 independent projects, originally defined in TDEC’s FY2023 Environmental Monitoring Plan (EMP) and subsequently completed over the course of FY2023 period of performance.

Ecological Resources Of A Heavily Modified And Utilised Temperate Coastal Embayment: Cockburn Sound, Peter J. Mitchell, Daniel E. Yeoh, Kurt N. Krispyn, Claire N. Greenwell, Sorcha Cronin-O’Reilly, Delphine B.H. Chabanne, Glenn A. Hyndes, Danielle Johnston, David V. Fairclough, Claire Wellington, Alan Cottingham, Gary Jackson, Jeffrey V. Norriss, Matias Braccini, Hector Lozano-Montes, Chandra P. Salgado Kent, Erin Clitheroe, Alissa Tate, James W. Penn, Marion Massam, Neil R. Loneragan, James R. Tweedley

Research outputs 2022 to 2026

Coastal environments and their associated biota provide numerous environmental, economic and societal services. Cockburn Sound, a temperate embayment on the lower west coast of Western Australia, is immensely important for the State and adjacent capital city of Perth. However, urbanisation and associated terrestrial and marine development has the potential to threaten this important ecosystem. This study collated published and unpublished data to review the current state of the ecological resources of Cockburn Sound and describe how they have changed over the past century. Post-WWII, the embayment began undergoing pronounced anthropogenic changes that limited oceanic water exchange, increased nutrient load, modified …

Seeds In A Pluriverse: Visakha Society For The Protection And Care Of Animals Inclusive Praxis Toward Self-Determined Just Socio-Ecological Territories, Priya Tallam

Antioch University Dissertations & Theses

My dissertation focuses on my thesis question: How might an NGO’s grassroots efforts in urban Visakhapatnam, India, propagate living justly with animals we encounter and severely Othered humans, beyond attitudes of guardianship, mitigating universalized harms to nature and society? In a transdisciplinary approach examining grassroots programs, my phenomenological study breaks down an animal advocate’s assertive practices of—inclusivity and decolonialized lived norms, which persistently transcend cultural antagonisms of caste, ability, gender, sex, class, and form/species—toward creating just pluriversal multispecies communities in Visakhapatnam. Universalized urbanization across the planet has driven irreversible socio-ecological transformation marked by record ecosystem decline. Sustaining the urban via …

21st-Century Stewardship: Infusing Environmental Education With Global Citizenship, Ava Y. Goodale

Antioch University Dissertations & Theses

In today's interconnected world, where socioecological issues transcend political borders, integrating environmental stewardship education with global citizenship education offers valuable opportunities for student empowerment. The goal of this multi-article dissertation was to conceptualize and operationalize 21st-century stewardship in educational settings. Twenty-first-century stewardship is a pedagogical approach that recognizes the limitations of environmental stewardship education as it is traditionally taught and is defined in Chapter II as an updated stewardship model that is infused with global citizenship’s multiscalar perspectives, global compacts, and layered identities to achieve its maximum impact in our interconnected world. This goal was first accomplished in Chapter II …

Ensemble Machine Learning Approaches For Bathymetry Estimation In Multi-Spectral Images, Kazi A. Islam, Omar Abdul-Hassan, Hongfang Zhang, Victoria Hill, Blake Schaeffer, Richard Zimmerman, Jiang Li

OES Faculty Publications

Traditional bathymetry measures require a large number of human hours, and many bathymetry records are obsolete or missing. Automated measures of bathymetry would reduce costs and increase accessibility for research and applications. In this paper, we optimized a recent machine learning model, named CatBoostOpt, to estimate bathymetry based on high-resolution WorldView-2 (WV-2) multi-spectral optical satellite images. CatBoostOpt was demonstrated across the Florida Big Bend coastline, where the model learned correlations between in situ sound Navigation and Ranging (Sonar) bathymetry measurements and the corresponding multi-spectral reflectance values in WV-2 images to map bathymetry. We evaluated three different feature transformations as inputs …

High Antarctic Coastal Productivity In Polynyas Revealed By Considering Remote Sensing Ice-Adjacency Effects, Hilde Oliver, Jessica S. Turner, Alexandre Castagna, Henry Houskeeper, Heidi Dierssen

OES Faculty Publications

Ocean color-based estimates of Antarctic net primary productivity (NPP) have indicated low nearshore productivity in ice-adjacent waters, contrasting with coupled physical–biogeochemical models. To understand this discrepancy, we assessed satellite records of polynya NPP by comparing field data with two satellite imagery datasets derived using different processing schemes. Our results indicate historical underestimation of chlorophyll a for imagery obtained using default atmospheric correction processing within approximately 100 km of ice-covered coastlines due to adjacency effects. Using radiative transfer modeling, we find that biases in ocean color polynya observations due to adjacency effects correspond to the high albedo of ice and snow. …

Yucatan Hurricane Activity Highlights Common Era Tropical Cyclone Dipole, Richard M. Sullivan, Peter J. Van Hengstum, Elizabeth J. Wallace, Sloan Coats, Jeffrey P. Donnelly, Robert Korty, Shawna N. Little, Martin G. Maas Vargas, Luis Mejia-Ortiz, Eduard G. Reinhardt, Courtney Schumacher, Anne E. Tamalavage, Tyler S. Winkler

OES Faculty Publications

Tropical cyclone (TC) impacts along the western Atlantic and Caribbean margin are not spatially uniform. Proxy based reconstructions of Common Era TC activity highlight this non-uniform distribution at centennial-millennial timescales. However, the sparse geographic scope of these reconstructions impedes our assessment of TC landfalls across broader spatial domains. This work presents a compilation of new and existing TC reconstructions from the Yucatan Peninsula for comparison with a contemporaneous compilation from New England, showing that these regions occupy distal nodes of a low-frequency TC dipole. Increased Yucatan (New England) storminess is closely linked to intervals of Northern Hemisphere warming (cooling) and …

Mapping The End Of Coal: How Policy Strength, Ownership, Finance Shape Global Plant Retirements, Jiwon Kim, Theodor Florian Cojoianu, Theodor F. Cojoianu, Maretno Agus Harjoto, Dariusz Wojcik

Research Collection College of Integrative Studies

This study examines how national environmental performance, institutional investor divestment from fossil fuels, investment in renewable energy, and ownership type influence the global phase-out of coal power plants, and whether these effects are constrained by geographical boundaries. Using data on coal plant retirements across 90 countries, we test whether domestic and cross-border factors shape the timing and likelihood of asset closure. We find that companies headquartered in countries with stronger environmental performance are more likely to retire domestic but not foreign plants. While institutional investors divestment is often assumed to exert cross-border influence, our findings show that divestment pressure by …

Integrating Indigenous Values And Community Strengths To Achieve Indigenous Food Sovereignty And Community Well-Being In The Ka’A’Gee Tu First Nation, Northwest Territories, Jennifer K. Temmer

Theses and Dissertations (Comprehensive)

Northern Indigenous communities face disproportionate impacts from interconnected challenges related to climate change, food security, health, and cultural preservation, that threaten traditional food systems and practices. While there is a growing recognition of the importance of community-driven solutions, existing frameworks fail to integrate Indigenous values and local priorities effectively. This research addresses this gap by exploring how the Ka’a’gee Tu First Nation (KTFN) is responding to these crises through climate change adaptation efforts focused on food system sustainability as a pathway to self-sufficiency and community well-being. To contribute to these efforts, this dissertation uses Participatory Action Research to facilitate community-driven …