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Leveraging Mammal Mycophagy To Determine Environmental Drivers Of Truffle Diversity, Brittany Hartsock

Electronic Theses and Dissertations

Many mycorrhizal fungi are hypogeous (truffle-forming), producing underground fruiting bodies. Studying truffles is inherently challenging due to their hidden nature. However, mycophagous mammals provide a unique opportunity to study hypogeous fungi because they rely on truffles as a food source. Although several truffle species have recently been described in the southern Appalachian region, their fruiting patterns remain poorly understood. To address this, we quantified truffle richness and spore loads from 670 Peromyscus scat samples collected across 42 sites spanning an environmental gradient during 2024 in the Blue Ridge Mountains of East Tennessee. We found that truffle richness and spore abundance …

Caribou Migration And Non-Local Hunting In Northwest Alaska: A Gis Analysis Of Hunting Activity And Its Relationship With Caribou Migration Corridors, Brittney L. Jiménezszabo

Geography and the Environment: Graduate Student Capstones

Indigenous Alaskans rely on subsistence hunting for food, with Barren-ground caribou making up approximately 27% of their diet. It is believed by subsistence hunters that non-local hunting is forcing a change in caribou migration behavior. This study examined non-local harvesting records from 2013 – 2025 in the northwest and interior Game Management Units (GMU) and Alaksa’s Western Arctic Caribou Herd (WACH) migration range data to answer the question, is there a spatial relationship between non-local harvests and WACH migration behavior. Mixed methods included spatial autocorrelation and local statistics. Findings led to the rejection of the null hypothesis which will help …

Inherited Local Shrinkage For Adaptive Functional Form Discovery, Jacob Colestin Schultz

Dissertations and Theses

Statistical models frequently employ nonlinear effects, interactions, and multiresolution basis expansions to represent complex relationships between predictors and responses. Determining the appropriate level of model complexity, however, remains a fundamental challenge. This dissertation introduces Inherited Local Shrinkage (ILS), a Bayesian global-local shrinkage framework for adaptive functional form discovery that enforces strong heredity among hierarchically related predictors.

ILS propagates shrinkage through directed acyclic graphs representing predictor inheritance, ensuring that increasingly complex terms are retained only when supported by simpler parent structure. The framework applies broadly to polynomial regression, interaction models, wavelets, splines, and other hierarchical basis expansions, while naturally extending to …

Staff Education On Psychoeducation Delivery To Enhance Medication-Adherence Education For Adults With Bipolar Disorder In An Outpatient Psychiatric Mental Health Facility, Bibiana Chinwe Ndula

Walden Dissertations and Doctoral Studies

This Doctor of Nursing Practice (DNP) staff education project addressed inconsistent delivery of evidence-based medication-adherence psychoeducation for adults with bipolar disorder (BD) in an outpatient psychiatric mental health facility. The project question was whether an 8-week structured module, in relation to existing staff education practices, would increase staff knowledge and confidence. The intervention was guided by the Johns Hopkins evidence-based practice (JHEBP) model and comprised a PowerPoint presentation, a facilitator guide, a handout, a checklist, a toolkit, and anonymous pre- and post-training assessments. Eight out of ten invited staff completed the project. The mean knowledge rose from 6.1 to 8.9 …

Dialogic Communication Ethics As A Hopeful Response To Artificial Intelligence, Kristen Haldeman

Electronic Theses and Dissertations

Within the past five years, a new technology has dominated modern culture: artificial intelligence. With a multiplicity of ways to respond to this new environment, this dissertation situates a response to artificial intelligence by combining the media ecology and communication ethics perspectives. Media ecology explores historical roots and biases of technology to learn about their influence of humanity. A dialogic communication ethics seeks to find an opening for hope to emerge. Hope, grounded in the works of Jacques Ellul and the Christian tradition, offers a new rhetorical perspective by shifting focus away from technology and to our neighbor.

Using Environmental Dna (Edna) As A Tool To Detect Sharks And Rays Along The Coast Of Quintana Roo, Mexico, Sara T. Norment

All HCAS Student Capstones, Theses, and Dissertations

Elasmobranchs play a critical ecological role in marine environments, yet many populations worldwide remain poorly known and monitored. This is particularly true in Mexico despite its high biodiversity and ongoing fishing pressures. Traditional monitoring methods, such as commercial fisheries and fishery-independent surveys using longlines or nets, are often limited, leaving important knowledge gaps. Previous studies have shown that environmental DNA (eDNA), small traces of DNA left behind in the water column from feces, skin, or mucus, is a transformative, non-invasive tool for detecting elasmobranch presence and diversity across marine ecosystems.

This project used eDNA metabarcoding to detect and identify elasmobranch …

A Genetic Analysis Of The Rare Endemic Astragalus Ripleyi Barneby, Juan Antonio Jaramillo-Chico

Master's Theses

Astragalus ripleyi Barneby is a rare endemic species found in the San Luis Valley of the southern portions of the Rocky Mountains in Colorado and New Mexico. Though not federally listed as endangered, the species is on the Bureau of Land Management’s Sensitive Species List, warranting protection and continued management. This study aims to provide information about the genetic health of the species to inform conservation efforts and provide updated management recommendations. A genetic health analysis was conducted investigating the levels of diversity present in the species, how genetic diversity is structured across the known range of the species and …

A Study Of Phylogenetic Relationships Of Dichanthelium Based On Plastomes, Humera Fatima

Theses

Dichanthelium (Hitchcock & Chase) Gould is a genus in the grass family (Poaceae) with a wide range of morphological diversity, exhibiting significant ecological differences. Despite this, its evolutionary relationships are not fully understood. The ambiguity surrounding the boundaries of lineages and the relationships among species has hindered the systematics of the genus. This study aimed to reconstruct the phylogenetic relationships within Dichanthelium, verify the monophyly of species, and evaluate the strength of the inferred relationships across different analytical frameworks. Molecular sequence data of entire plastomes were examined using both maximum likelihood and Bayesian inference methods to develop phylogenetic hypotheses. Phylogenies …

The Role Of Individual Specialization In Migration Phenology And How Restored Habits Are Used By Native And Nonnative Fishes, Austin Garner

All Graduate Theses and Dissertations, Fall 2023 to Present

Native fish species around the world have declined due to habitat loss, habitat fragmentation, and the spread of non-native species. Because these problems often happen at the same time and interact, recovery efforts can stall unless they address all of the factors limiting a species' comeback. The June sucker (Chasmistes liorus), native only to Utah Lake, UT, has declined for many of these reasons, though its recovery effort has made significant progress due in large part to a successful hatchery program. Yet, the recovery efforts have not yet been able to establish a self-sustaining population in Utah Lake, …

Behavioral And Landscape Factors Affecting The Effectiveness Of Egg-Bait Management For Common Ravens In The Great Basin, Usa, Sierra L. Pederson

All Graduate Theses and Dissertations, Fall 2023 to Present

Common Ravens have become increasingly common across the Great Basin of the western USA, largely because human activities, such as roads, agriculture, livestock operations, and human-made structures, provide them with abundant food, water, and nesting sites. As raven numbers have grown, so has their impact on vulnerable species like the greater sage-grouse. Like many other ground-nesting species, greater sage-grouse eggs and chicks are especially susceptible to predation. To help reduce raven numbers in sensitive areas, wildlife managers often place hard-boiled chicken eggs treated with a toxin (DRC-1339) on the landscape, expecting that ravens will die after eating these eggs and …

Long-Term Spatiotemporal Change In Coral Reef Fish Populations And Communities In The Philippines, John Christopher Whalen

Biological Sciences Theses & Dissertations

The Visayas Region of the Philippines is a global epicenter of marine fish biodiversity. Hypotheses attribute this peak of species richness within the Coral Triangle to processes that occur at geological time scales. However, changes in biodiversity may occur on ecological time scales, allowing for the assessment of the potential impact of anthropogenic activities. Recent declines in genetic, species, and ecosystem diversity have been observed in the tropics, including the Philippines. Within the Philippines the Visayas Region is considered the epicenter of species adversity due to anthropogenic stressors such as habitat degradation, overfishing, and harvesting individuals for the aquarium trade. …

Harnessing Airborne And Spaceborne Lidar For Large-Area Assessment Of Canopy Structural Complexity, Tahrir Ibraq Siddiqui

Theses

Forests play a vital role in global carbon cycling, biodiversity conservation, and the provision of ecosystem services. Accurate quantification of forest carbon sequestration rates – or forest production – therefore is essential for understanding ecosystem dynamics and informing sustainable forest management practices. Light detection and ranging (LiDAR) systems, as an active remote sensing modality, have emerged as a powerful tool for capturing detailed structural information of forests. Studies employing terrestrial LiDAR demonstrated that canopy structural complexity (CSC) metrics are strongly correlated with forest production at stand to landscape scales. While terrestrial LiDAR systems provide highly detailed maps of internal canopy …

Reconstructing Stand-Age Structure In A Wet Miombo Woodland Using Dendrochronology, Zambia, Clara Tiyembekeze Zulu

All-Inclusive List of Electronic Theses and Dissertations

Dendrochronological research in tropical Africa has remained limited, leaving critical gaps in stand-age structure and climate-growth relationships in seasonally dry tropical woodlands. This study reconstructed stand-age structure and assessed climate sensitivity in the wet Miombo woodland of African Explosives Limited (AEL) forest, Copperbelt Province, Zambia. Field sampling was conducted during four African Dendrochronology Fieldschools (2021-2024) using a Modified Variable Area Transect (MVAT) design across nine plots. The series intercorrelation was 0.351; the average mean sensitivity was 0.423. The oldest tree was 170 years old, and more than 70% of the sampled species showed potential for dendrochronology. Markhamia obtusifolia was the …

From Fields To Flu: Mapping H5n1 Zoonotic Risk In California Rice Fields, Mariati Messinger

Walden Dissertations and Doctoral Studies

Highly Pathogenic Avian Influenza (HPAI) H5N1 threatens agriculture, wildlife, and public health in California, where flooded rice fields in the Central Valley provide surrogate wetland habitat for migratory waterfowl and may create ecological interfaces for viral spillover into poultry systems. This quantitative ecological study examined whether county-level rice acreage, Lesser Snow Goose activity, and their interaction were associated with poultry HPAI H5N1 outbreak incidence during complete winter seasons available for analysis. Guided by One Health and disease ecology frameworks, secondary data from USDA, eBird, PRISM, and public surveillance sources were analyzed for 36 county-winter observations using negative binomial regression, logistic …

A Socio-Ecological Study Of Coyote And Human Interactions In San Francisco Bay Open Space Preserves, Zhiyi Zhou

Master's Theses

Urban open space preserves support both intensive recreation and wildlife, but the information on carnivore activity and visitor perceptions is limited. This study combined camera-trap monitoring and on-site visitor surveys to evaluate activity patterns of medium- to large-bodied mammals and perceptions of coyotes at Windy Hill and Rancho San Antonio Open Space Preserves (South San Francisco Bay Area). From October 2024 to July 2025, thirteen cameras recorded 213,681 photo events; detections were standardized as detections per 1,000 camera-hours. Ten mammal species and two avian species were detected, including four focal carnivores: coyote (Canis latrans), bobcat (Lynx rufus), mountain lion (Puma …

Time Series Analysis Of Temperature And Pollen Exposure On Asthma Outcomes In Atlanta, Georgia, Victoria Okereke-Viktorsson

Walden Dissertations and Doctoral Studies

The effects of climate change contribute to volatile temperature changes, which coupled with pollen exposure pose a significant threat to asthmatic people, potentially impacting methods for asthma management. The purpose of this ecological time-series study was to use the carbon dioxide theory of climate change, Dutch hypothesis, and social ecological model to estimate the relationship between average temperature and average pollen concentrations on average asthma morbidity outcomes for adults living in metropolitan Atlanta from 2020 to 2022 (N = 37,913). Results varied in terms of years, socioeconomic status (SES) vulnerability, gender, and racial group. Overall, a linear regression model revealed …

Spatiotemporal Patterns Of Vaccine Uptake For Measles Outbreaks In Katsina State, Nigeria, Zeenat Kabir Asma'i

Walden Dissertations and Doctoral Studies

Measles remains a public health concern in Nigeria despite the availability of effective vaccines, yet limited research has comprehensively examined spatiotemporal patterns and contextual determinants of vaccination coverage and measles incidence in Katsina State. Guided by the socioecological model, this quantitative ecological study examined spatiotemporal patterns of measles incidence among children aged 9–59 months of age across 183 wards in 34 local government areas of Katsina State, Nigeria, from 2018 to 2022. Confirmed cases (n = 376) were analyzed using negative binomial regression and spatial methods, including Moran’s I, SaTScan, and geographically weighted regression (GWR). Urban wards had higher incidence …

Learning Across Landscapes: An Interactive Minnesota Ecology Book, Blake Berney

School of Education and Leadership Student Capstone Projects

This capstone project focused on the development of an educational book introducing elementary-aged readers to Minnesota’s native trees and the biomes in which they may be found. The project was influenced by teachings from the Dakota, Ojibwe, and current work from the Minnesota DNR. The book explores Minnesota’s major biomes and highlights native trees through accessible descriptions, photographs, activities, and connections to the landscapes and communities where these species are found. Information was then adapted for an elementary-school audience and organized into a cohesive educational resource. Design work included creating the book’s layout, incorporating original photographs and interactive activities, and …

“A Beautiful Mess: Rebirthing Through Earth, Dance, And The Divine”, Mikayla Douglas

MFA in Dance Theses

A Beautiful Mess: Rebirthing Through Earth, Dance, and the Divine by Mikayla Douglas is a culmination of research, creative practice, and lived experience that was developed during her time at Saint Mary’s College of California in the MFA Dance Program. This thesis investigates the shared dialogue between eco-somatics, eco-phenomenology, motherhood, nature, and the BIPOC birthing body. Through the use of outdoor somatic practices, personal reflection and stories, Mikayla Douglas explores how nature can serve as a site of healing, embodiment, and reclamation for Black and Brown birthing bodies. The research of this thesis work is grounded heavily in both scholarly …

Destination “Burning River”: Restoration And Placemaking In A Rust Belt City, Mia Compton-Engle

Geography Undergraduate Senior Theses

In 1969, the Cuyahoga River in Cleveland, Ohio caught fire from industrial pollution. Media narratives reframed the river fire as a symbol of environmental degradation, discursively transforming the Cuyahoga River from a place of industrial sacrifice to a place deserving ecological stewardship. Consequently, the river fire catalyzed the modern American environmental movement and local urban river restoration, materially transforming the Cuyahoga River from a place of industrial waste to a place of natural beauty and socioeconomic opportunity. Thus, urban river restoration presents an opportunity for novel placemaking: a local microcosm of the global turn towards urban sustainability. However, there is …

Prosocial Behaviors As A Protective Factor Against Suicide Risk: An Ecological Momentary Assessment Approach, Bradley A. Brown

USF Tampa Graduate Theses and Dissertations

Suicidal ideation (SI) fluctuates substantially over short timescales, and the Interpersonal Theory of Suicide proposes that suicidal thinking emerges through dynamic interpersonal states involving perceived burdensomeness (PB), thwarted belongingness (TB), and hopelessness regarding these interpersonal states (IH). Although ecological momentary assessment (EMA) research has demonstrated that these risk factors fluctuate meaningfully within individuals and are associated with short-term changes in SI, comparatively little research has examined interpersonal processes that may attenuate suicide risk in real time. Prosocial behavior — voluntary actions intended to benefit others — may represent one such process, yet no known EMA study has examined whether prosocial …

The Relationship Between The Environment And Pollution With Surgical Outcomes And Disparities, Wendelyn Marie Oslock

ETDs from 2020-2029

Air pollution exposure has been linked to many surgically managed diseases and adverse health events that occur in the postoperative period. Despite this, the impact of air pollution on postoperative recovery is poorly understood. This knowledge gap may be one of the underlying mechanisms for persistent disparities in surgical outcomes. Previous studies have found racial and economic disparities in air pollution exposure. These same communities have been shown to experience worse surgical outcomes. The goal of this thesis is to explore if exposure to air pollution impacts surgical outcomes and determine if disparities in socioeconomic factors impact this relationship. The …

The Impact Of The Covid-19 Pandemic On Obstetric Access In Rural And Urban Areas In The United States, Sandali Chandradasa

Walden Dissertations and Doctoral Studies

No abstract provided.

Stories From The Pantanal: Documentary Filmmaking And Conservation In A Changing Wetland Landscape, Tobin Yates

Environmental Studies Senior Theses

This thesis pairs a short documentary film, Umbigo do Pantanal, with a written component examining conservation in Brazil's Pantanal wetland. Six days of fieldwork in Mato Grosso in September 2025 centered on Sandro Sebastião Godofredo, a multi-generational Pantaneiro rancher whose 130,000-hectare property is transitioning from intensive cattle operations toward ecosystem-based conservation and ecotourism. Sandro's account, drawn from interviews recorded on his ranch and along the São Lourenço River, anchors a broader argument about the limits of single-species conservation models in the Pantanal. The dominant jaguar-focused approach concentrates ecotourism revenue in a small portion of the wetland while pushing the costs …

Rethinking Functional Groupings In Basketball Wings Through Ecological Trait Frameworks, Dhruv Mehrotra

Theses and Dissertations

This paper starts with a review about Plant Functional Types and then goes deeper into the conceptual foundations of Plant Functional Types (PFT's) with detailed discussion of global trait spectra such as the leaf economics spectrum and the fast-slow continuum. Using concepts like response and effect traits, the review then talks about how a trait based ecological framework can provide a more robust guideline to classify plants. The review then talks about how players in basketball have been classified in the past along with some of the newer typologies. The review starts to draw some parallels between the ecological framework …

Photocatalytic Advanced Oxidative Processes (Aop) As A Promising Agricultural Runoff Treatment Solution For The California Central Valley, Briana Miller

Master's Projects and Capstones

Pesticide pollution in the California Central Valley (CV) is a major concern for aquatic toxicity. This research will determine if photocatalytic advanced oxidation processes (AOP), an emerging water treatment technology, could be implemented within the CV to degrade pesticides. A case study, literature review, comparative analysis, and policy analysis were conducted to identify pesticides of concern within the CV, if photocatalytic AOP can degrade those pesticides, how photocatalytic AOP compares to current technologies, and regulatory challenges with implementing photocatalytic AOP. Between 2019 and 2023, the top 30 most applied pesticides were identified, with 12 chemicals identified as aquatic toxicants, seven …

Structure And Diversity Of Play Behavior In Juvenile Belding's Ground Squirrels, Paul O'Driscoll Ii

Master's Theses

Play behavior is ubiquitous among juvenile mammals and can promote motor, social, and cognitive development, providing multiple adaptive benefits to young animals in some cases. The structure of play can be linked to the benefits it confers on individuals. I evaluated the structure of play in juvenile Belding’s ground squirrels (Urocitellus beldingi), a species for which multiple adaptive benefits of play have been identified. I compared juvenile play in U. beldingi to adult sexual and aggressive behavior to determine and classify similarities between juvenile play and adult behavior. I evaluated diversity in the behaviors expressed during play interactions and diversity …

Rainbow Promises, Uneven Promises: Framing Lgbtqia+ Educational Policy And Possibility In Education, Gerardo Lorenzo-Saucedo

Dissertations

Despite the expansion of LGBTQIA+ inclusive policies in K-12 education, disparities in students’ experiences with safety and belonging persist. This qualitative case study examines how such policies are interpreted and enacted within a high school and district in Southern California, and how these processes shape LGBTQIA+ students’ experiences.

Guided by ecological systems theory, queer theory, and multiple streams theory, this study conceptualizes policy implementation as a dynamic and socially constructed process influenced by power, ideology, and institutional context. Data were collected through interviews, document and artifact analysis, and observations, with analysis that used a multi-phased coding procedure.

Findings revealed that …

Investigating Changes In The Stable Isotopic Composition Of Juniperus Osteosperma Over 34,000 Years Of Climatic Shifts, Lisa S. Garcia

Biology ETDs

Isotopic compositions of plants from the past provides empirical evidence for paleoclimatic shifts and plants physiologically response. This study used Neotoma paleomiddens (fossilized debris piles) collected from Death Valley National Park, which contained preserved abundant plant materials. These middens range from modern to >35,000 years and capture different climatic events in Earth history. Employing Juniperus osteosperma (Utah Juniper) leaves found in middens, I investigated variation in carbon and nitrogen stable isotopic composition. To help interpret paleomidden results, we used modern field and herbaria samples of Juniperus from a spatial gradient stretching across their geographic range. Results showed δ ¹³C …

Assessment Of Local Ecological Knowledge, Oyster Predation, And Habitat Function To Improve Management Of Nearshore Habitats, Cynthia Evelyn Marie Lupton

Theses and Dissertations

Coastal ecosystems along the northern Gulf of Mexico are ecologically and economically vital yet increasingly threatened by environmental change, habitat degradation, and knowledge gaps that complicate restoration and management efforts. This dissertation integrates social and ecological approaches to improve understanding of predator dynamics, stakeholder perceptions, and habitat function related to nearshore habitats. Thereby, providing information that can inform adaptive management and restoration in the region through addressing three overarching objectives: 1) evaluate stakeholder perceptions of oyster (Crassostrea virginica) predation and management practices; 2) quantify environmental and habitat factors influencing oyster drill (Stramonita haemastoma complex) abundance; and, 3) assess the influence …