Digital Commons Network^™

Orthotrichum Lyellii As An Active Moss Biomonitor: Examining The Interplay Between Ambient Pm10, Bulk Deposition And Heavy Metals In An Urban Environment, Scott Bradley Kiel

Dissertations and Theses

The importance of monitoring and preventing pollution in the environment is a globally recognized issue. Of the criteria pollutants outlined by the United States Environmental Protection Agency, particulate matter is among these least understood in relation to toxicity and most wide-spread. Many governments have employed continuous air quality monitoring networks to track ambient levels of particulate matter, but are often too widespread to capture the heterogeneity of the urban environment, especially for heavy metal deposition. In Portland, OR, the epiphytic moss Orthotrichum lyellii was successfully used as a low-cost passive biomonitor to increase the spatial resolution of pollution around the …

Arbuscular Mycorrhizal Fungi Colonization Response To Dike Removal In The Salmon River Estuary, Elinore Webb

Dissertations and Theses

Arbuscular mycorrhizal fungi (AMF) form symbiotic relationships with wetland plants and are important to the restoration of coastal estuaries. The purpose of this study was to assess the presence and colonization of arbuscular mycorrhizal fungi in Distichlis spicata from three formerly diked areas of the Salmon River Estuary to determine an initial understanding of the mycorrhizal community in tidal wetlands post-restoration. AMF were present in all four sample areas and total colonization ranged on average 39-72%. The reference site had the lowest levels of total colonization, which is contrary to the findings of studies of younger wetland restorations. Most importantly, …

Modeling Postfire Effects On Snow Albedo And Forest Recovery Over A Chronosequence Of Burned Forests In The Triple Divide Region Of The Rocky Mountains, Anton J. Surunis

Dissertations and Theses

Wildfires impact snow albedo, forest cover, and forest structure and thus snow melt rate and snowpack supply for as long as 15 years following burn. These effects have not been quantified at fine spatial resolutions and long time periods at a watershed scale. I modeled the effects of postfire effects on snow albedo, snow-mass energy balance, and resulting snow-water equivalent (SWE) depth over a long-time scale and at a fine spatial resolution. Using a spatially and temporally distributed snow evolution model called SnowModel, I modeled postfire effects on snow albedo and forest structure over postfire recovery within 8 forest fires …

Efficiency In The Upper Deschutes Basin: Understanding The Hydrosocial Implications Of Irrigation Canal Piping, Rebecca Anderson

Dissertations and Theses

In response to water scarcity, irrigation efficiency projects aim to conserve water for in-stream flow and agricultural use. Piping irrigation canals is a common irrigation efficiency method which reduces the loss of incidental recharge, resulting in trade-offs within a hydrosocial system. Few studies have focused on the consequences of canal piping and none have integrated a critical analysis of the social factors involved in deciding what constitutes 'efficient' water use. This study seeks to fill this gap by combining natural and social science to give attention to the scales and perspectives involved in irrigation efficiency canal piping and the material …

"We've Created Cheap Energy Off The Backs Of Salmon": Dam Removal Politics And Alliances In The Lower Snake River Basin, Krista Harrington

Dissertations and Theses

Dams, once considered by many to be good for water development in the Western U.S., might not be a part of a climate resilient future. Dams have come under increasing scrutiny due to undesirable ecological implications. Although dam removal proposals are growingly popular in recent decades, they are controversial since they impact different stakeholders in different ways. In the Pacific Northwest, the Lower four Snake River dams have long been criticized for their negative impacts on salmon. In February 2021, US Congressman Mike Simpson (R-Idaho) proposed a comprehensive framework to deconstruct the Lower four Snake River dams as an attempt …

Mapping Ecosystem Service Flows Of Estuary Restoration Projects On The Oregon Coast To Identify Impacted Stakeholders, Shersten King Finley

Dissertations and Theses

The recent impetus for estuarine restoration has largely focused on resolving key ecological problems; however, less is known about how people might benefit or be impacted by restoration. By mapping benefits that flow from functional salt marshes and estuarine systems I examined how different social groups might be impacted by restoration based on race and class. In this study, I considered three ecosystem services (recreation, aesthetics, cultural/historical/spiritual) and where they might impact surrounding communities. In this paper I argue that stakeholder groups can be identified by mapping ecosystem service flow areas. I hypothesized that these three ecosystem services would have …

Transformative Ecoliteracy Development In Postsecondary Education: Cultivating Intentional Relationships Through Garden-Based Learning, Shevawn Armstrong

Dissertations and Theses

Education can play a critical role in empowering learners to address the global, complex, and interconnected sustainability problems humanity currently faces. Ecoliteracy, as an educational aim, may support the cultivation of values, attitudes, and skills required for the development of sustainability solutions and our collective ability to design regenerative ways of living. However, empirical research that explores and supports the development of ecoliteracy in adults is limited. This grounded theory action research study aimed to contribute to this body of knowledge. This study explored how adult ecoliteracy and practical gardening skills may be cultivated through an intentionally designed, holistic, garden-based …

The Connections Between Innovation, Culture, And Expertise In Water Infrastructure Organizations, Alice Brawley-Chesworth

Dissertations and Theses

Infrastructure organizations are notoriously conservative and resistant to change, even when faced with wicked problems that cannot be solved with the same thinking used in the past. In the water sector, this resistance to change has been linked to an industry culture that is based in a single, engineering-oriented knowledge system. Scholars have suggested that diversification of knowledge systems is necessary for implementation of innovations that will move the sector forward to solve wicked problems.

This research used a qualitative case study approach comparing two water sector organizations in Portland, Oregon. One organization included members who shared an engineering knowledge …

Stakeholder Participation And Influence At State Public Utility Commissions, Genevieve Theresa Kruse

Dissertations and Theses

Despite the international consensus that climate change is a problem, few substantive policies are being pushed forward at the national level to meet international greenhouse gas reduction commitments under the Paris Agreement. The most significant climate change policies are emerging at state public utility commissions (PUCs). While PUCs were traditionally structured to regulate utilities, state PUCs are now finding themselves at the hub for renewable energy, clean energy, and distributed energy policies. Despite the increase in renewable and clean energy policies at state PUCs, there is a noticeably small environmental and clean energy stakeholder presence at those PUC proceedings. A …

Mass Capacity Analysis Of Stormwater Control Measures Using Synthetic Stormwater With Silica, Organic And Hydrocarbon Constituents, Craig Michael Fairbaugh

Dissertations and Theses

Stormwater control measure (SCM) performance is well studied regarding solids removal; however, analysis of mass loading capacity, long-term performance, and maintenance demands are challenging due to the variability and multiple constituents inherent in urban stormwater. This research examines the long-term water quality performance and sediment mass capacity of two common SCMs: high rate biofiltration (HRBF) and conventional bioretention (BRT). Pollutant removal trials were conducted in a laboratory setting per the New Jersey Department of Environmental Protection (NJDEP) filtration protocol in two phases: the first using inorganic sediment per the NJDEP protocol, the second phase with the addition of organic sediment …

Coming To Know The Local Environment: Children's Experiences In Rautamai Gaunpalika, Nepal, Elsie Nicole Love

Dissertations and Theses

This qualitative research, conducted over three months from late monsoon season into early fall of 2018 with twenty-six children and thirteen adults, explores how children in the hills of Rautamai Gaunpalika, Province 1, Nepal come to know their local environment. Semi-structured interviews with children, their family members, and teachers, and participant observation with children as they worked and played in forests, fields, and streams, suggest that outside of school, children come to know their local environment in the following ways: through participation in and application of knowledge to subsistence practices; through collaborative learning and teaching in mixed-age groups; through relationships …

Temperature And Predator Effects On Green Crabs (Carcinus Maenas) And Their Distribution In South Slough National Estuarine Research Reserve, Elissa Connolly-Randazzo

Dissertations and Theses

The invasive green crab (Carcinus maenas) has increased in abundance and distribution among Oregon's estuaries. Its global success in establishing in new environments and tolerance for abiotic stressors, such as temperature, raises concern for C. maenas to negatively influence native crab species, especially given global climate change. To improve in predicting invasion impacts, this work analyzed the results from a controlled tank experiment at Portland State University and the field data on a population of C. maenas in South Slough National Estuarine Research Reserve (SSNERR). The aquarium experiment documented predation pressure on C. maenas across a range of …

Effects Of Green Crab (Carcinus Maenas) Across Variable Densities Of Eelgrass (Zostera Marina), Kimberly Alexis Brown

Dissertations and Theses

Eelgrass (Zostera marina) plays a critical role in estuarine ecosystem function by sustaining a variety of marine and freshwater species, but it's increasingly threatened by the aggressive non-native green crab (Carcinus maenas). The abundance of C. maenas is on the rise within the coastal environment of Oregon and it is imperative to know how these populations will affect the long-term health of Z. marina. C. maenas have been linked to declines in Z. marina coverage and shellfish abundance, but there has been no research on to what extent the density of Z. marina affects its …

The New Shiny Penny? Regenerative Agriculture Beliefs And Practices Among Portland's Urban Agriculturalists, Melia Ann Chase

Dissertations and Theses

Regenerative agriculture (RA) is a set of farming and land management practices intended to support or enhance soil health and carbon sequestration potential of soils while producing food, fiber, or other agricultural products. It has received broad acclaim from scholars, corporations, and governmental bodies as a potential means of sequestering carbon and mitigating climate change impacts. It has also received critique and pushback for its vague definition, shifting metrics, and lack of acknowledgement of the Indigenous practices underlying the modern suite of regenerative practices. The purpose of this research is to investigate the beliefs Portland, Oregon urban agricultural practitioners hold …

Heat, Wildfire And Energy Demand: An Examination Of Residential Buildings And Community Equity, Chrissi Argyro Antonopoulos

Dissertations and Theses

Extreme heat and wildfire events are becoming more prolific and exacerbated by climate change, carrying significant implications for environmental and social systems. Residential buildings play a central role in protecting people from heat and pollutant exposure during extreme weather events, but the level of protection varies dramatically depending on building energy efficiency and technology availability. Low-income and communities of color have higher energy burdens compared to affluent populations, and underserved communities often do not have financial resources for, or access to, advanced building technologies. This dissertation explores the impacts of extreme heat and wildfire on residential buildings, focused specifically on …

More Than Words: Articulating The Multisensory Experiences Of Protected Area Visitors In Southern Nevada, Sara Nicole Temme

Dissertations and Theses

The complex sensory experiences of visitors to U.S. protected areas are not well understood. Previous research investigates visitor activities, motivations, and the ways place attachment cultivates support for conservation activities and other pro-environmental behavior. However, it is unclear how protected area visitor sensory experiences contribute to these behaviors. This study aims to articulate the multisensory experiences of visitors to the Desert National Wildlife Refuge Complex and the Spring Mountains National Recreation Area in southern Nevada, U.S.A. Specifically, it demonstrates the complexity of these experiences as present, intertwined, and embodied in all visit phases: before, during, and after. Utilizing a mixed-method …

Sea Surface Temperatures And Vertical Wind Shear As Precursors To Tropical Cyclone Activity In The Caribbean And An Expanding Main Developing Region, Keneshia Hibbert

Dissertations and Theses

Sea surface temperatures and vertical wind shear are essential to tropical cyclone formation. TCs need warm SSTs and low shear for genesis. Increasing SSTs and VWS changes influence storm development. This work analyzes SST and VWS trends for the Caribbean, surrounding region, and the Atlantic hurricane main developing region from 1982 to 2020. Storm intensity increases significantly during this period. Annual and seasonal trends show regional SSTs in the MDR are warming annually (0.0219°C yr^-1) and per season (0.0280°C yr^-1). Simultaneously, VWS decreases during the late rainfall season at 0.0556m/s yr^-1 in the MDR and …

Data Fusion And Synergy Of Active And Passive Remote Sensing; An Application For Freeze Thaw Detections, Zahra Sharifnezhadazizi

Dissertations and Theses

There has been a recent evolvement in the field of remote sensing after increase of number satellites and sensors data which could be fused to produce new data and products. These efforts are mainly focused on using of simultaneous observations from different platforms with different spatial and temporal resolutions. The research dissertation aims to enhance the synergy use of active and passive microwave observations and examine the results in detection land freeze and thaw (FT) predictions. Freeze thaw cycles particularly in high-latitude regions have a crucial role in many applications such as agriculture, biogeochemical transitions, hydrology and ecosystem studies. The …

A Citizen-Science Approach For Urban Flood Risk Analysis Using Data Science And Machine Learning, Candace Agonafir

Dissertations and Theses

Street flooding is problematic in urban areas, where impervious surfaces, such as concrete, brick, and asphalt prevail, impeding the infiltration of water into the ground. During rain events, water ponds and rise to levels that cause considerable economic damage and physical harm. The main goal of this dissertation is to develop novel approaches toward the comprehension of urban flood risk using data science techniques on crowd-sourced data. This is accomplished by developing a series of data-driven models to identify flood factors of significance and localized areas of flood vulnerability in New York City (NYC). First, the infrastructural (catch basin clogs, …

Ecological Changes Of The Lower Niobrara River Valley And Lewis And Clark Lake Delta From Past To Present, Madalyn Christine Bollig

Dissertations and Theses

Over half of the world’s large river systems are impacted by dams. These may prevent sediment flow downstream, resulting in accumulation in the upstream reservoir. On the Missouri River, deltas and associated backwater-affected areas occur in nine locations across six reservoirs. One of these, the Lewis and Clark Lake delta-backwater, is influenced by sediment inputs from both the Missouri River and the Niobrara River. While the extension of the prograding delta into the reservoir has been well documented, there has been little research on upstream (backwater) effects of the delta on the lower Niobrara River. This study examined ecological changes …