Physical Sciences and Mathematics Commons^™

The Cultivation Of Ulva Lactuca In Jambiani, Zanzibar: A Case Study, Jazmine R. Compton

Anthós

This case study explores the feasibility of Ulva lactuca cultivation in Jambiani, Zanzibar, Tanzania. The seaweed farming industry in Zanzibar is facing challenges related to climate change that have resulted in increased rates of crop failure and decreased production. Cultivation of the green algae Ulva lactuca has been suggested as a potential solution due to its tolerance to extreme environmental conditions. In collaboration with Marine Cultures, this project has tested different cultivation methods typically used for red algae (Rhodophyta) species. Experimental plots of Ulva lactuca were established in Jambiani, Zanzibar using the floating line and off- bottom methods. At the …

Remediating History – A Review Of Restoration For Creeks Polluted From Historical Mining Sites, With The Red Boy Mine As A Primary Case Study, Kara Atiyeh

University Honors Theses

I conducted a literature review to examine the key aspects of restoring watersheds affected by pollution from historical mining. This review is then applied to a case study discussion of the Red Boy Mine and Clear Creek remediation project in Granite, Oregon. The goal of this discussion is to explore how an analysis of site conditions along with current literature on management practices can help guide these projects. Thousands of abandoned hard rock mines remain throughout the country, and many pose serious environmental health effects. Heavy metals like cadmium, nickel, and copper are brought to the surface from mining activity, …

Matching The Scales Of Planning And Environmental Risk: An Evaluation Of Community Wildfire Protection Plans In The Western Us, Matthew Hamilton, Cody Evers, Max Nielsen-Pincus, Alan Ager

Environmental Science and Management Faculty Publications and Presentations

Theory predicts that effective environmental governance requires that the scales of management account for the scales of environmental processes. A good example is community wildfire protection planning. Plan boundaries that are too narrowly defined may miss sources of wildfire risk originating at larger geographic scales whereas boundaries that are too broadly defined dilute resources. Although the concept of scale (mis)matches is widely discussed in literature on risk mitigation as well as environmental governance more generally, rarely has the concept been rigorously quantified. We introduce methods to address this limitation, and we apply our approach to assess scale matching among Community …

Beavers Beyond Boundaries: Perceptions Of Beaver-Related Restoration, Matthew V. Guziejka

Student Research Symposium

The study "Beavers Beyond Boundaries: Perceptions of Beaver-Related Restoration" conducted by Matt Guziejka and Heejun Chang from the WISE Lab, Department of Geography at Portland State University, delves into the social, cultural, and environmental dimensions of Beaver-Related Restoration (BRR) within the urban setting of the Tualatin River watershed. Utilizing a voluntary survey with 187 participants across three urban watershed sites, the research aimed to analyze community perceptions concerning beavers and their impact on the environment, particularly in relation to their proximity to watercourses. Findings indicate that proximity significantly affects attitudes towards beavers, with those living closer to watercourses demonstrating more …

Extreme Precipitation Climatology Of The Contiguous U.S., Amy M. Johnson

Student Research Symposium

Extreme precipitation can cause flooding, landslides, loss of life and assets. Across the Contiguous United States (CONUS), concurrent to global warming, many communities have experienced increases in the amount of rain falling during the most extreme precipitation events and climate models project further increases for most of the CONUS. There is a need to comprehensively study the extreme precipitation climatology across the CONUS to understand what is within the observed range of extreme precipitation and the weather that drives it. Modern Era Retrospective analysis for Research and Applications 2 (MERRA-2) atmospheric reanalysis data for the period of 1980-2023 is used …

The Influence Of Soil Composition On Stormwater Retention And Runoff In Green Roofs At Portland State, Manuel Edrozo, Lily Green, Mitchell Mcdonald, Nicholas Olmos

Student Research Symposium

The purpose of this study is to determine what soil composition is best for green roofs at Portland State; we aim to compare the current soil to the original substrate, to measure which composition retains the most water, and which filters out the most pollutants in stormwater runoff. Five different soil compositions were tested — original, current, layered mixed, solid mixed, and potting soils — and 1,000mL of high and low intensity rainfall (in/hr) was simulated for each of the mixtures. Water was allowed to filter through the soils for a predetermined time (10min for a high application rate and …

Recovery Of Black Carbon Concentrations In Burned Forests, Monica V. Zapata Villegas, Kelly E. Gleason

Student Research Symposium

Forest fires shed light absorbing particles (LAP), such as black carbon and burned woody debris, into snowpacks, darkening snow surface albedo, and advancing snowmelt timing and snow disappearance patterns for decades following fire. Although the role of LAPs in seasonal snow has been extensively studied in recent years, the spatiotemporal variability of LAPs and contributions to snowmelt relative to years since fire and burn severity is still unknown. In the Triple Divide region of western Wyoming, the headwaters of the Colorado, Columbia, and Missouri rivers, we quantified the spatiotemporal variability of forest fire effects on snow albedo, using geochemical analysis …

Multiscale Variability Of Heavy Metals In A Western U.S. Snowpack, Kelsey Hefner

Student Research Symposium

Natural and anthropogenically sourced particulates are deposited from the atmosphere to landscapes via dry and wet deposition, making frozen winter snowpack a natural archive of atmospheric elemental composition. Wildfires in the Western United States are increasing in extent, duration, and severity, especially in alpine regions. Severe fires remove forest canopy and can impact how atmospheric elements are dispersed and stored across snow-dominated watersheds. We evaluated Al, V, Cr, Mn, Ni, Cu, As, Zn, Se, Mo, Cd, and Pb concentrations in 394 winter snow core samples. We collected samples in 2019 and 2020 from a chronosequence of eight forests that burned …

Wildland Urban Interface Growth And Development Potentials In Deschutes County, Samantha Hall

Student Research Symposium

Policy can and has been used as a tool to reduce the risk communities experience from natural hazards by limiting development in areas most vulnerable. How and where development occurs directly influences the amount of risk a community experiences from natural hazards like hurricanes, earthquakes, flash floods, and wildfire among others. Development patterns that contribute to increased wildfire risk mostly occur within the wildland urban interface, a land use type where development is at the fringes or intercept of wildland areas and is more flammable due to surrounding vegetation, slope, local climate, and other factors. For this research, Deschutes County …

Method Validation Of Metals In Environmental Soil Samples, Sofia Deangelis, Nana Nguyen

Student Research Symposium

Vehicles are a major source of metal accumulation in terrestrial environments. Green infrastructure, such as bioswales, has been implemented as a way to mitigate this damage. However, there is a limited understanding of the processes that occur in these bioswales as few go back after implementation to identify areas in the bioswale with accumulation of pollutants. Inductively coupled mass spectrometry (ICP-MS) has the potential to be used in this type of study due to the machine’s high sensitivity and selectivity. However complications can arise while using the ICP-MS to characterize complex environmental samples. This study seeks to optimize microwave assisted …

Community Responses To Us Regional Clean Hydrogen Hubs, Bethani Turley

Student Research Symposium

In 2023, the Bipartisan Infrastructure Law designated 7 billion dollars to fund regional hydrogen hubs across the US with the goal of kickstarting a utility scale hydrogen economy for the US electric grid. A promising technology in the renewable energy transition, hydrogen can be made from a multitude of energy sources, often designated by colors: green hydrogen is made from solar and wind, pink hydrogen from nuclear, and blue hydrogen from natural gas. This presentation examines this new hydrogen economy through the case study of the Appalachian Regional Clean Hydrogen Hub (ARCH2). ARCH2 is a blue hydrogen hub proposal by …

Learning To Teach About Climate Justice And Social Justice In Science Methods, Mindy J. Chappell

Northwest Journal of Teacher Education

In November, the Editors of NWJTE sat down for a conversation with Dr. Mindy J. Chappell, a Science Teacher Educator in the College of Education at Portland State University. Dr. Chappell’s passions include developing teachers who are prepared to disrupt normative science ideologies and provide young people with science instruction that encourages and empowers them to be leaders in their communities. She engages in arts-based educational science research through the methodology of Ethnodance (a term she coined). She places young people and their lived experiences at the heart of her work.

Feminist Political Ecology In The Classroom, Ella J. Yeigh

Northwest Journal of Teacher Education

As the effects of climate change are being felt more frequently, discussions on how to combat such a massive issue are increasingly prevalent. Finding solutions to the climate crisis requires an understanding of how mainstream economic systems have led to the climate crisis and using these same principles to get out of the climate crisis is misguided. Economic actions have inherent value biases that have real political effects. Feminist Political Ecology (FPE) as a theoretical model presents a better understanding of how values that are inherent in economic models such as reliance on efficiency, markets, and continual economic growth have …

Non-Native Rhizophora Mangle As Sinks For Coastal Contamination On Moloka’I, Hawai’I, Geoffrey Szafranski, Elise F. Granek, Michelle L. Hladik, Mia Hackett

Environmental Science and Management Faculty Publications and Presentations

Coastal mangrove forests provide a suite of environmental services, including sequestration of anthropogenic contamination. Yet, research lags on the environmental fate and potential human health risks of mangrove-sequestered contaminants in the context of mangrove removal for development and range shifts due to climate change. To address this, we conducted a study on Moloka'i, Hawai'i, comparing microplastic and pesticide contamination in coastal compartments both at areas modified by non-native red mangroves (Rhizophora mangle) and unmodified, open coastline. Sediment, porewater, and mangrove plant tissues were collected to quantify microplastic and pesticide concentrations across ecosystem type. Average microplastics were similar between …

Supply Is Not Limulus: Research Review Of Horseshoe Crab Conservation In The Face Of Intense Pharmaceutical Demand, Zoya Galeev

University Honors Theses

Horseshoe crabs are being used by the pharmaceutical industry to conduct endotoxin tests using LAL derived from the organism’s blood to ensure safe medical practice. Their annual collection and bleeding, while not always leading to mortality, affects horseshoe crab behavior and health. This research seeks to understand how the American horseshoe crab, L. polyphemus, is being used by pharmaceutical agencies and the implications that their harvesting has on the industry and the conservation of the species. Studies were collected from the past decade across two databases, Web of Science (WOS) and PubMed, to assess present conservation techniques to reduce …

Rising Water Temperature In Rivers: Ecological Impacts And Future Resilience, Matthew F. Johnson, Lindsey K. Albertson, Adam C. Algar, Stephen J. Dugdale, Patrick Edwards, Judy England, Christopher Gibbins, Multiple Additional Authors

Environmental Science and Management Faculty Publications and Presentations

Rising water temperatures in rivers due to climate change are already having observable impacts on river ecosystems. Warming water has both direct and indirect impacts on aquatic life, and further aggravates pervasive issues such as eutrophication, pollution, and the spread of disease. Animals can survive higher temperatures through physiological and/or genetic acclimation, behavioral and phenological change, and range shifts to more suitable locations. As such, those animals that are adapted to cool-water regions typically found in high altitudes and latitudes where there are fewer dispersal opportunities are most at risk of future extinction. However, sub-lethal impacts on animal physiology and …

Where The Rubber Meets The Road: Emerging Environmental Impacts Of Tire Wear Particles And Their Chemical Cocktails, Paul M. Mayer, Kelly D. Moran, Susanne Brander, Stacey L. Harper, Manuel Garcia-Jaramillo, Elise F. Granek, Multiple Additional Authors

Environmental Science and Management Faculty Publications and Presentations

About 3 billion new tires are produced each year and about 800 million tires become waste annually. Global dependence upon tires produced from natural rubber and petroleum-based compounds represents a persistent and complex environmental problem with only partial and often-times, ineffective solutions. Tire emissions may be in the form of whole tires, tire particles, and chemical compounds, each of which is transported through various atmospheric, terrestrial, and aquatic routes in the natural and built environments. Production and use of tires generates multiple heavy metals, plastics, PAH's, and other compounds that can be toxic alone or as chemical cocktails. Used tires …

Reconnecting A Stream Channel To Its Floodplain: Implications For Benthic Diatoms And Macroinvertebrate Trophic Structure, Patrick M. Edwards, Nicole C. Popp, Yangdong Pan, Christine L. Weilhoefer, Aspen Peterman, Lauren Mork, Matthew F. Johnson, Megan Colley, Multiple Additional Authors

Environmental Science and Management Faculty Publications and Presentations

Streams systems draining upland landscapes provide valuable ecosystem services, but they are vulnerable to incision and channelization caused by anthropogenic disturbance. Restoring a degraded stream to its pre-disturbance condition by reconnecting the channel to its historical floodplain aims to recover lost hydro-morphological processes and functions. Seeking evidence to indicate whether that aim is met in practice, we examined diatoms and the stream macroinvertebrate trophic structures in three reaches of Whychus Creek, Oregon, United States. Two reaches were reconnected to their pre-disturbance floodplains in 2012 and 2016. The third, control reach, was not restored and was selected to represent the degraded …

Editorial: Innovating A New Knowledge Base For Water Justice Studies: Hydrosocial, Sociohydrology, And Beyond, Melissa Haeffner, Jenia Mukherjee, Rebecca Lave, Jamie Linton, John Ndiritu, Raul Pacheco-Vega, Maria Ruska, Margreet Zwarteveen

Environmental Science and Management Faculty Publications and Presentations

Creating a new knowledge base that centers water justice (Zwarteveen and Boelens, 2014; Sultana, 2018; Wölfle-Hazard, 2022) in hydrosocial and sociohydrology studies involves a broader discussion about why justice matters, how to work toward this goal, and what the implications for research praxis are. The articles in this Research Topic approach different angles of water justice: as law (Fernández and Alba), a social movement (Dame et al.), practice (Pool et al.; Reeves and Bonney), cases of injustice (Caretta et al.), and theory (Krueger and Alba). From this Research Topic, we find that the interrelated concepts of naturecultures and care can …

Watershed, Lake, And Food Web Factors Influence Diazotrophic Cyanobacteria In Mountain Lakes, Lara Jansen, Daniel Sobota, Yangdong Pan, Angela Strecker

Environmental Science and Management Faculty Publications and Presentations

Cyanobacterial blooms can occur in freshwater ecosystems largely isolated from development and not experiencing extensive cultural eutrophication. For example, remote mountain lakes can experience intense blooms of diazotrophic (nitrogen-fixing) cyanobacteria caused by factors acting at different spatial and temporal scales. In this study, we examined how cross-scale interactions among watershed, lake, and food web characteristics influence diazotrophic cyanobacteria biovolume in mountain lakes. We quantified diazotrophic cyanobacteria biovolume, zooplankton abundance, and physico-chemical variables for 29 lakes in the Cascade Mountains of Oregon, USA, in summer 2019. Watershed characteristics were compiled from historical datasets available for the region. Diazotrophic cyanobacteria biovolume ranged …

Juvenile Dungeness Face High Predation Risk From Green Crabs Across Increased Temperatures At Different Salinities, Trever Gelling

Environmental Science and Management Undergraduate Departmental Honors Theses

Marine heatwaves, altered precipitation regimes, and other changing climate conditions are altering the abiotic conditions of Oregon’s estuaries. Furthermore, warmer water temperatures are correlated with the range expansion and population growth of the invasive and broadly tolerant Carcinus maenas, the green crab, in Oregon. Metacarcinus magister, Dungeness crab, one of Oregon’s most valuable fishery species, is also facing these climate stressors, and their young that recruit to estuaries overlap with C. maenas adults. Therefore, we wanted to determine impacts of C. maenas on young-of-the-year (YOTY) M. magister and the roles of salinity, temperature, and predator size in mediating these impacts. …

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 …

The Effects Of Salt Marsh Restoration On The Hydrology Of Salt Marsh Channels, Isis Kontas

University Honors Theses

Salt marshes produce many ecosystem services, from water purification to protection from hurricanes. Despite their benefits, salt marshes have been impacted negatively by human activities. There are many salt marsh restoration projects that intend to bring back all ecological functions and services. Quantifiable measurements are needed to evaluate the effectiveness of such restoration efforts. Earlier work by Reagan Thomas demonstrated what happens to the hydrology of salt marsh channels when they are adjacent to restored salt marshes. This study builds on Thomas’ work and uses the sinuosity of channels as a quantitative, representative metric of salt marsh hydrology restoration effectiveness. …

How Beavers (Castor Canadensis) Affect Habitat Availability For Two Native Oregon Turtles: Actinemys Marmorata And Chrysemys Picta Bellii, Rodé Krige

University Honors Theses

Oregon is home to two native freshwater turtle species: the northwestern pond turtle and the western painted turtle. Both turtles are Oregon conservation strategy species with a status rating of sensitive, indicating declining populations. Oregon’s decline in these turtle’s populations is thought to be predominantly due to loss and degradation of habitat that results from development and urbanization. Beavers’ ability to dam streams and create ponds may be creating habitat usable by turtles, but the relationship is under-studied. This study assessed water temperature, basking habitat, and overall turtle habitat suitability at beaver-dammed and control ponds in Portland, Oregon. Average basking …

Coastal Wetland Restoration Through The Lens Of Odum's Theory Of Ecosystem Development, Friedrich W. Keppeler, Annette S. Engel, Linda M. Hooper-Bùi, Paola C. López-Duarte, Charles W. Martin, Jill A. Olin, Katelyn J. Lamb, Michael J. Polito, Nancy N. Rabalais, Multiple Additional Authors

Environmental Science and Management Faculty Publications and Presentations

Advancing ecological restoration assessments requires a more detailed consideration of species interactions and ecosystem processes. Most restoration projects rely on a few metrics not always directly linked with ecological theory. Here, we used Odum's theory of ecosystem development to assess and compare the ecosystem structure and services of created marshes (4–6 years old) with preexisting, reference marshes in a brackish water region of the Mississippi River Delta. We built ecosystem models for created and reference marshes that integrated large datasets of stomach contents, stable isotopes, and taxa abundances. Despite strong resemblance in community structure, created marshes were at an earlier …

Evidence Of Transboundary Movement Of Chemicals From Mexico To The U.S. In Tijuana River Estuary Sediments, Flannery Mclamb, Kesten Bozinovic, Zuying Feng, Damian Shea, Miguel F. Vasquez, Chris Stransky, Richard M. Gersberg, Goran Bozinovic, Multiple Additional Authors

Center for Life in Extreme Environments Publications

The Tijuana River Estuary (TRE) has been a public health hazard and point of contention between the United States and Mexico for decades, with sources of pollution on both sides of the border. The goal of our study is to determine the presence and dynamics of chemical contamination in the TRE. We sampled sediment from four TRE locations in the U.S. during stable dry conditions and immediately after a wet weather period. Organic chemicals were initially screened with non-targeted analysis using gas chromatography high-resolution mass spectrometry (GC/HRMS) that tentatively identified 6978 chemicals in the NIST 20 database. These tentative identifications …

When Communities Face Drinking Water Crises, Bottled Water Is A 'Temporary' Solution That Often Lasts Years--And Worsens Inequality, Daniel Jaffee

Sociology Faculty Publications and Presentations

As a sociologist, I study the social and environmental effects of the rapid growth of bottled-water consumption in the U.S. and beyond, and how it is linked to distrust of public tap water. In my new book, “Unbottled,” one chapter examines how these dynamics played out in Flint. As its example shows, communities can end up relying on bottled water – often at great expense – for years after a crisis.

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 …