Physical Sciences and Mathematics Commons^™

How Are Oregon's Rural Indigenous Communities Overcoming Water Access Issues?, Tyren John Thompson

Dissertations and Theses

This study investigates how water insecurity affects Indigenous communities in Grand Ronde, Warm Springs, and Umatilla, Oregon, through loss of clean drinking water, access to culturally significant foods, and exposure to pollution. Each community offers innovative solutions drawing on their Indigenous knowledge to overcome water supply challenges. Communities with more resources are better equipped to cope with water insecurity and environmental degradation.

Tiny Drifters Amidst Global Change: Examining Environmental Drivers, Trophic Impacts, And Management Strategies Of Estuarine Plankton Communities In The Anthropocene, Taylor Nicole Dodrill

Dissertations and Theses

Plankton productivity supports estuarine food webs, and has been tied to the success of fisheries, macroinvertebrates, and cultured shellfish yields. Climate change and alterations to nutrient loads are thought to be influencing plankton assemblages, with toxin-producing harmful algal blooms (HABs) on the rise and nutritional quality of plankton declining globally. These shifts in plankton communities may contribute to low biomass yields and toxin-based closures of important fisheries. The objectives of this dissertation are to identify environmental drivers, trophic impacts, and management strategies to understand and respond to changing estuarine plankton communities. To address these objectives, I used a combination of …

Modeling Leaf-Level Transpiration: Exploring The Consequences Of Assumed Saturated Vapor Pressure In Leaves, Danlyn L. Brennan

Dissertations and Theses

Understanding the dynamics of water transport through leaf intercellular airspaces (IAS) and its impact on transpiration is crucial for accurate predictions of plant water use and ecosystem response to changing climates. This study investigates the implications of assuming undersaturation of water vapor in the IAS for transpiration predictions and explores potential modifications to standard modeling approaches.

A dynamic 1D soil-plant-atmosphere continuum using a stomatal optimization model (SPAC-SOT) framework was used to simulate the response of tree species, P. edulis, to prolonged drought and varying environmental conditions. Comparisons between two model assumptions (saturated vs. undersaturated IAS) reveal notable differences in …

Wasted Space, Ryan Martyn

Dissertations and Theses

This paper performs a spatial analysis of Portland, Oregon, with a focus on identifying and utilizing "wasted space," such as parking lots and vacant land, as strategic opportunities to enhance the completeness of the city. The planning concept of a "complete neighborhood" is defined as a locality that offers residents access to all essential aspects of daily life within a convenient walking distance. This notion encompasses elements, such as walkability, accessibility to essential services and amenities, sustainability, and equity. The objective of this study is to provide a more precise definition of the planning concept of a complete neighborhood and …

The Influence Of Polystyrene Microplastics On Juvenile Steelhead Trout (Oncorhynchus Mykiss), Kaitlyn Marie Baker

Dissertations and Theses

Mass production of plastic within the past decade has led to over 100 billion tons of plastics being added to the world’s oceans through rivers and effluent disposal and decomposition. For marine environments, the sudden and constant growth of microplastics (plastics 1 µm to 5 mm in diameter), is of particular concern to top-predatory fish such as steelhead trout (Oncorhynchus mykiss), who passively or actively uptake microplastics while consuming prey. Previous research has demonstrated clear detrimental impacts of microplastic accumulation in bivalves, seabirds, and zebrafish, including decreased diet, reproduction rates, and metabolism, as well as increased rates of …

Community Adaptations To Wildfire Risk In Central Oregon, Usa: An Empirical Study Of Inclusionary Practices In Collaborative Wildfire Risk Mitigation, Liam Resener

Dissertations and Theses

Adverse impacts of wildfire in Western North America have become increasingly present through the 21^st century, driven by landscape changes imposed by colonists in the 19^th and 20^th centuries. Community adaptations to wildfire will be necessary through the 21^st century to restore landscapes and protect the safety and livelihoods of people who live in at-risk areas. Wildfire risk extends across countless environmental and social systems, and individuals have competing ideas about what constitutes that risk and how to best adapt to it. As resources are being allocated to community adaptations, important questions emerge about the values …

Exploring Nonprofit Views On Water Management And Conservation Strategies, Jillian Marie Farley

Dissertations and Theses

Valuing water resources presents a multitude of methodological and theoretical challenges, including economics, biodiversity, and cultural significance. Information is not readily available on the individuals working every day on water resource management and how they navigate such a complex topic. This project is designed to help all parties better understand the opinions of individuals working for nonprofit organizations and Watershed Councils in the State of Oregon about current methods of water resource conservation. The results reflect respondents’ personal views on the process and practices of valuing water and are designed to prompt deeper discussions between the organizations, communities, and policymakers. …

Race And Income As Predictors Of Trust In Flood Mitigation Strategies, Wendy Nathaly Sangucho Loachamin

Dissertations and Theses

Trust plays a central role in coastal flooding management because the support or opposition to costly mitigation strategies depends, in part, on how much stakeholders trust in the effectiveness of these strategies. Despite the importance of trust in the approval of flood mitigation strategies, trust is rarely measured. Furthermore, Environmental Justice (EJ) studies have consistently shown that BIPOC (Black, Indigenous and People of Color) and low-income communities are more vulnerable to environmental hazards. Therefore, if these communities are more exposed to flooding, we hypothesize they will have less trust in flood mitigation strategies to protect them; yet trust is understudied …

The Radical Relationality Of Complex Partnerships: Community-Member Experiences In Critical Community-Based Learning, Amie Riley

Dissertations and Theses

Through a radical relationality within the social-ecological systems that sustain us, critical community-based learning (CBL) in higher education offers a praxis for engaging the demanding pedagogical and community challenges we face. When CBL is implemented as both a critical and sustainability pedagogy, as a strategy for social change, the relationships created by CBL partnerships have the potential to generate transformational outcomes for all partnership agents. Using a critical complexity theoretical framework, a bricolage of complexity science and critical theory, this critical qualitative study sought to understand the systemic patterns and behaviors of a community-based learning partnership by elevating community-member voices. …

Drivers And Dynamics Of Phytoplankton Communities And Harmful Algal Blooms In Mountain Lakes, Lara Stephanie Jansen

Dissertations and Theses

Harmful cyanobacterial blooms (cyanoHABs) are a complex and widespread disturbance in freshwater water bodies, impacting water quality for wildlife and human populations. While cyanobacteria often bloom in warm lakes impacted by human development like agriculture, blooms are increasingly reported in cooler waters with limited development in the surrounding watershed. As much of cyanoHAB research has focused on lakes in highly developed watersheds, the understanding of factors leading to cyanobacteria dominance and blooms in the absence of major development remains limited. Mountain lakes can serve as ideal systems to study bloom-forming cyanobacteria in watersheds with minimal development. In addition, mountain lakes …

Phytoplankton Community As An Indicator Of Cyanobacteria Harmful Algal Blooms In High Mountain Lakes, Victoria Elizabeth Avalos

Dissertations and Theses

Cyanobacteria blooms are a growing issue worldwide and can be harmful to both aquatic life and human health. Warm temperatures, nutrient loading, stable water columns, and selective grazing of zooplankton and phytoplankton can contribute to cyanobacteria bloom formation. In this study, I characterized the algal communities and water quality differences in two physiographically similar lakes with relatively little human influences, Odell and Crescent Lakes, Oregon, to better understand potential contributing factors to cyanobacteria harmful algal bloom formation (cyanobacteria bloom) in Odell Lake.

There are three hypotheses in this study:

1. If there was a cyanobacteria bloom in Odell Lake, but not …

Impacts Of Floodplain Restoration On Water Temperature And Macroinvertebrates In Whychus Creek, Oregon, Wesley Nathan Noone

Dissertations and Theses

Stream restoration is a proposed climate adaptation tool, however, outcomes of floodplain restoration on stream temperature have been debated. Despite a growing number of studies that investigated water temperature in restored streams, few have quantified thermal heterogeneity in new habitat types created by restored hydrogeomorphic processes and the impact of thermal diversity on the aquatic macroinvertebrate community. In this study, I evaluated three hypotheses: 1) restoration increases habitat diversity, 2) habitat diversity increases water temperature heterogeneity, and 3) restored reaches have more diverse macroinvertebrate communities. I collected a total of 40 macroinvertebrate samples and characterized environmental conditions in three reaches …

Pakistan, India And The Indus River Basin, Muquadas Ilyas

Dissertations and Theses

Water is a fundamental need of all living things. The right to clean water is classified as a human right under United Nations Resolution 64/292.As such it is the responsibility of governments to ensure its citizens are not deprived of this essential resource. In doing so, effective water management is crucial to provide clean water that is accessible to everyone regardless of any challenges such as geographical constraints or political disputes. This thesis explores the water management efforts of Pakistan and India. These countries are facing a water crisis, whereby numerous citizens have died due to dehydration and diseases contracted …

Advancing The Accuracy Of Watershed Analysis Across Diverse Hydrometeorological And Geologic Regimes Via Classification And Analysis Of Gpm-Imerg Products, Jake M. Longenecker

Dissertations and Theses

The analysis and protection of watersheds, along with spring water resources, depend on the accurate identification of catchments. Building on previous research that correlated spring hydrographs with high-resolution, satellite-based Global Precipitation Measurement – Integrated Multi-satellitE Retrievals for GPM (GPM-IMERG) data, I improve the speed and accuracy of catchment identification and hydrodynamic characterization via an enhanced Empirically Constrained Hydrologic Operation (ECHO) algorithm. This research (1) establishes optimal parameter inputs for the algorithm to enable reliable identification of source point-locations, (2) removes human in-the-loop processing, and thus reduce potential operator bias, and (3) explores the potential for using a limited dataset of …