Physical Sciences and Mathematics Commons^™

Microplastics Presence In Rhizophora Mangle Roots Throughout Fishponds And Open Coasts In Moloka'i, Hawaii, Mia Hackett

University Honors Theses

Microplastics (MP) are an emerging global contaminant that has drawn the attention of many researchers in the last few decades due to their growing environmental threats. Pieces of plastic smaller than 5 mm, they are specifically a high cause for concern in marine environments as their small size allows them to flow from inland into the ocean. Through this movement, MPs have been found in all marine ecosystems and ingested by hundreds of marine species often mistaking them for food. Labeled as one of the most threatened ecosystems, mangrove forests are already a large sink for a variety of contaminants …

Management Plan For The Western Painted Turtle At The Sandy River Delta In Troutdale, Oregon, Emma Scott

Environmental Science and Management Professional Master's Project Reports

This management plan has been prepared for the Lower Columbia Estuary Partnership and is intended to provide guidance for the improvement and protection of western painted turtle (Chrysemys picta bellii) habitat at the Sandy River Delta in Troutdale, Oregon. The Sandy River Delta is a 1500-acre natural area situated where the Columbia and Sandy Rivers meet. Its dynamic floodplain habitat supports a diverse assemblage of species, including the western painted turtle, an Oregon Conservation Strategy Species. A small, unknown number of western painted turtles utilize the wetland habitats of the Sandy River Delta, and the frequency in observations …

Data From: The Geography Of Glaciers And Perennial Snowfields In The American West, Andrew G. Fountain, Bryce Glenn, Hassan J. Basagic

Geology Faculty Datasets

A comprehensive mid-20th century inventory of glaciers and perennial snowfields (G&PS) was compiled for the American West, west of the 100° meridian. The inventory was derived from U.S. Geological Survey 1:24,000 topographic maps based on aerial photographs acquired during 35 years,1955–1990.

An Economical And Repeatable Method For Mapping Shade Cast On Water Channels, Eric M. Nielsen

Institute for Natural Resources Publications

The motivation of this work is to provide insights toward determining a viable strategy for statewide monitoring of riparian vegetation condition, with particular focus on developing a repeatable, costeffective method for assessment of progress toward achieving temperature-based water quality standards mandated by the federal Clean Water Act. A reliable monitoring strategy could in turn support a datadriven prioritization and assessment framework to increase the efficiency, effectiveness and accountability of riparian restoration efforts. In this project we developed and tested a method for mapping shade cast on water channels by riparian vegetation using optical imagery sources that are affordable and regularly …

Detection And Quantification Of Arsenic Pollution With A Moss Bio-Indicator And Icp-Ms, Erin R. Bowey

University Honors Theses

Heavy metal pollution is a recognized concern with an established source of anthropogenic activity, which is ever-increasing. While work has been done to make the monitoring of some metals more accessible, resourceful, and efficient with the use of epiphytic moss as a bio-indicator, this method has not been optimized for the detection of arsenic. Previously used analytical instrumentation has not proven sensitive enough to reliably detect arsenic, creating a gap in the monitoring process. However, inductively coupled plasma mass spectrometry (ICP-MS) is proposed as the solution to fill this gap. Its potential for low limits of detection and quantification express …

Spatial And Temporal Variations Of Microplastic Concentrations In Portland's Freshwater Ecosystems, Rebecca Talbot, Elise F. Granek, Heejun Chang, Rosemary Wood, Susanne Brander

Geography Faculty Publications and Presentations

While microplastics are a pollutant of growing concern in various environmental compartments, less is known regarding the sources and delivery pathways of microplastics in urban rivers. We investigated the relationship between microplastic concentrations and various spatiotemporal factors (e.g., land use, arterial road length, water velocity, precipitation) in two watersheds along an urban-rural gradient in the Portland metropolitan area. Samples were collected in August, September, and February and were analyzed for total microplastic count and type. Nonparametric statistics were used to evaluate potential relationships with the explanatory variables, derived at both the subwatershed and near stream scales. In August, microplastic concentrations …

Extreme Winds Alter Influence Of Fuels And Topography On Megafire Burn Severity In Seasonal Temperate Rainforests Under Record Fuel Aridity, Cody Evers, Andres Holz, Sebastian Upton Busby, Max Nielsen-Pincus

Environmental Science and Management Faculty Publications and Presentations

Nearly 0.8 million hectares of land were burned in the North American Pacific Northwest (PNW) over two weeks under record-breaking fuel aridity and winds during the extraordinary 2020 fire season, representing a rare example of megafires in forests west of the Cascade Mountains. We quantified the relative influence of weather, vegetation, and topography on patterns of high burn severity (>75% tree mortality) among five synchronous megafires in the western Cascade Mountains. Despite the conventional wisdom in climate-limited fire regimes that regional drivers (e.g., extreme aridity, and synoptic winds) overwhelm local controls on vegetation mortality patterns (e.g., vegetation structure and …

Estimating Transport Of Diesel Particulate Emissions In The Portland Metro Using Lagrangian-Based Dispersion Modeling, Andrew Mckinley Rogers

Environmental Science and Management Professional Master's Project Reports

Air pollution from diesel combustion is a well-known and serious problem which adversely impacts human and environmental health throughout the world. One of the primary pollutants of concern from diesel combustion are the solid particles formed as a byproduct of the incomplete combustion of the diesel, also known as diesel particulate matter. As a result of the ubiquitous use of diesel-fired engines in urban environments, understanding the transport of diesel particulate matter from the exhaust is paramount in assessing human exposure to this toxic pollutant. Air dispersion modeling is one method to study how diesel particulate matter is transported and …

Carli Creek Regional Water Quality Project: Assessing Water Quality Improvement At An Urban Stormwater Constructed Wetland, Christopher L. Desiderati

Environmental Science and Management Professional Master's Project Reports

Stormwater management is an ongoing challenge in the United States and the world at-large. As state and municipal agencies grapple with conflicting interests like encouraging land development, complying with permits to control stormwater discharges, “urban stream syndrome” effects, and charges to steward natural resources for the long-term, some agencies may turn to constructed wetlands (CWs) as aesthetically pleasing and functional natural analogs for attenuating pollution delivered by stormwater runoff to rivers and streams. Constructed wetlands retain pollutants via common physical, physicochemical, and biological principles such as settling, adsorption, or plant and algae uptake. The efficacy of constructed wetlands for pollutant …

Identifying And Prioritizing Urban And Commercial Stormwater Concerns: City Of Grants Pass, Oregon, Amie Nicole Siedlecki

Environmental Science and Management Professional Master's Project Reports

For many communities, drinking water comes from surface water sources, or source water, such as rivers and creeks. Within the city of Grants Pass, Oregon, this is the case. The Rogue River, which spans 215 miles, beginning near Crater Lake and emptying into the ocean at Gold Beach, is Grants Pass' Rogue River, in relation to drinking water, is rarely an issue for the City of Grants Pass' Public Works Department, the potential contaminant sources (PCS) from the urban, commercial, and industrial geographical areas of Grants Pass is a concern. In order to deploy treatment processes that are capable of …

Closed Canopies Crowd Out Bats: Planning Artificial Gap Creation, Alana Simmons

Environmental Science and Management Professional Master's Project Reports

Managed even-aged forest stands often lack small to medium-sized canopy gaps that help to increase habitat diversity and, in turn, wildlife diversity. A large body of literature suggests that this habitat diversity is especially important for bat communities and that bat activity and diversity can be depressed in closed canopy, even-aged stands. Open- and edge-adapted bats have evolved specific wing morphologies and echolocation call structures that make them reliant upon forest gaps as energy efficient foraging grounds in otherwise structurally cluttered forests. Artificial gap creation projects that increase habitat diversity have been implemented to benefit ungulates, and a similar approach …

Data From: Drivers Of Zooplankton Community Composition In A Novel Ecosystem: Hawai’I Mangroves As A Case Study, Casey L. Lewis, Elise F. Granek

Environmental Science and Management Datasets

Management of established non-native plants is challenging because removal is expensive and can produce negative consequences, yet establishment can create novel ecosystems. Red mangrove propagules were introduced to Moloka'i, Hawai’i in 1902 to mitigate the effects of soil erosion and have since spread along the coast and to adjacent islands creating novel habitat. We compared zooplankton communities between novel mangrove and historical non-mangrove habitat both within fishponds and along open coastline to examine environmental factors, including mangrove presence, affecting zooplankton community composition.

Community composition patterns were driven by lunar cycle and site characteristics, including fishpond structure, mangrove and open coast …

A Community Of Fear: Emotion And The Hydro-Social Cycle In East Porterville, California, Michael Egge, Idowu Ajibade

Geography Faculty Publications and Presentations

Broader governance challenges driving water insecurity globally are well documented in the literature, however the power-laden relationships and emotions that shape water access at the household and community levels are yet to be fully investigated, especially in the context of water consolidation projects. In this article, we examine the role of emotions in mediating access to water and in the production of resource struggles among marginalized communities, existing outside of conventional regulatory frameworks. We bring together two relational approaches – the hydro-social cycle and emotional political ecology – to examine water insecurity and how it manifests in the historically disadvantaged …

An Examination Of Limiting Factors Of Chrysemys Picta Bellii (Western Painted Turtles) In The Lower Willamette River Basin, Oregon, James P. Holley

Environmental Science and Management Professional Master's Project Reports

Oregon’s two native freshwater turtle species, Chrysemys picta bellii (Western painted turtle) and Actinemys marmorata (Northwestern pond turtle), have seen significantly reduced population sizes since the founding of Portland in 1845, with estimates of up to 90% for A. marmorata. This project examined turtle nesting activity at 25 sites across a range of turtle populations and habitats around the Lower Willamette River Basin. All discovered turtle nesting activity was found in areas of high solar exposure. We found 93% of over 400 nest attempts to have been depredated across the 25 sites, well above most other reported rates. At …

Data From: Forest Density Intensifies The Importance Of Snowpack To Growth In Water-Limited Pine Forests, Kelly E. Gleason, John B. Bradford, Anthony W. D’Amato, Shawn Fraver, Brian J. Palik, Michael A. Battaglia

Environmental Science and Management Datasets

Research Study
Warming climate and resulting declines in seasonal snowpack have been associated with drought stress and tree mortality in seasonally snow-covered watersheds worldwide. Meanwhile, increasing forest density has further exacerbated drought stress due to intensified tree-tree competition. Using a uniquely detailed dataset of population-level forest growth (n=2495 sampled trees), we examined how inter-annual variability in growth relates to snow volume across a range of forest densities (e.g., competitive environments) in sites spanning a broad aridity gradient across the United States. Forest growth was positively related to snowpack in water-limited forests located at low latitude, and this relationship was intensified …

Collecting Plant Phenology Data In Imperiled Oregon White Oak Ecosystems: Analysis And Recommendations For Metro, Kirsten Wright

Environmental Science and Management Professional Master's Project Reports

Imperiled Oregon white oak ecosystems are a regional conservation priority due to the rich biodiversity they support, including rare and endemic species such as Oregon state-listed endangered pale larkspur (Delphinium leucophaeum). Previously dominant in the Pacific Northwest, upland prairie and oak woodlands are now under significant threat, with only 2% remaining in the Willamette Valley in small fragments.

Over the past 150 years, conversion to agriculture, urban development and fire suppression have dramatically reduced and degraded Oregon white oak habitat. Climate change has now emerged as an additional threat, causing observable shifts in plant phenology. In fragile oak …

Daily Stream Samples Reveal Highly Complex Pesticide Occurrence And Potential Toxicity To Aquatic Life, Julia E. Norman, Barbara J. Mahler, Lisa H. Nowell, Peter C. Van Metre, Mark W. Sandstrom, Mark A. Corbin, Yaorong Qian, James F. Pankow, Wentai Luo, Nicholas B. Fitzgerald, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

Transient, acutely toxic concentrations of pesticides in streams can go undetected by fixed-interval sampling programs. Here we compare temporal patterns in occurrence of current-use pesticides in daily composite samples to those in weekly composite and weekly discrete samples of surface water from 14 small stream sites. Samples were collected over 10–14 weeks at 7 stream sites in each of the Midwestern and Southeastern United States. Samples were analyzed for over 200 pesticides and degradates by direct aqueous injection liquid chromatography with tandem mass spectrometry. Nearly 2 and 3 times as many unique pesticides were detected in daily samples as in …

Examining The Complex Relationship Between Innovation And Regulation Through A Survey Of Wastewater Utility Managers, Luke Sherman, Alida Cantor, Anita Milman, Michael Kiparsky

Geography Faculty Publications and Presentations

Despite pressures to increase performance and decrease costs, innovation has been slow to emerge in the municipal wastewater sector. The relationship between regulation and innovation in this sector is a particularly interesting aspect of this conundrum, given the degree to which public utility decision-making is influenced by regulation. Using a national survey, this paper examines US wastewater utility managers’ perceptions of how regulation influences the adoption of new technologies. Recognizing that the relationship between innovation and regulation is complex, we develop the concept of regulation as multifaceted and examine three interrelated aspects of regulation: (1) regulatory requirements, (2) regulators and …

A Digital Archive Of Human Activity In The Mcmurdo Dry Valleys, Antarctica, Adrian Howkins, Stephen M. Chignell, Poppie Gullett, Andrew G. Fountain, Melissa Carrie Brett, Evelin Preciado

Geography Faculty Publications and Presentations

Over the last half century, the McMurdo Dry Valleys (MDV) of East Antarctica have become a globally important site for scientific research and environmental monitoring. Historical data can make important contributions to current research activities and environmental management in Antarctica but tend to be widely scattered and difficult to access. We address this need in the MDV by compiling over 5000 historical photographs, sketches, maps, oral interviews, publications, and other archival resources into an online digital archive. The data have been digitized and georeferenced using a standardized metadata structure, which enables intuitive searches and data discovery via an online interface. …

Effects Of Environmentally Relevant Concentrations Of Microplastic Fibers On Pacific Mole Crab (Emerita Analoga) Mortality And Reproduction, Dorothy Horn, Elise F. Granek, Clare Steele

Environmental Science and Management Faculty Publications and Presentations

Microplastics are ubiquitous in marine systems; however, knowledge of the effects of these particles on marine fauna is limited. Ocean-borne plastic debris accumulates in littoral ecosystems worldwide, and invertebrate infauna inhabiting these systems can ingest small plastic particles and fibers, mistaking them for food. We examined the effect of microplastic fibers on physiological and reproductive outcomes in a nearshore organism by exposing Pacific mole crabs (Emerita analoga) to environmentally relevant concentrations of microsized polypropylene rope fibers. We compared adult gravid female crab mortality, reproductive success, and embryonic developmental rates between microfiber-exposed and control crabs. Pacific mole crabs exposed to polypropylene …

Microplastic Concentrations In Two Oregon Bivalve Species: Spatial, Temporal, And Species Variability, Britta Baechler, Elise F. Granek, Matthew V. Hunter, Kathleen E. Conn

Environmental Science and Management Faculty Publications and Presentations

Microplastics are an ecological stressor with implications for ecosystem and human health when present in seafood. We quantified microplastic types, concentrations, anatomical burdens, geographic distribution, and temporal differences in Pacific oysters (Crassostrea gigas) and Pacific razor clams (Siliqua patula) from 15 Oregon coast, U.S.A. sites. Microplastics were present in organisms from all sites. On average, whole oysters and razor clams contained 10.95 ± 0.77 and 8.84 ± 0.45 microplastic pieces per individual, or 0.35 ± 0.04 pieces g⁻¹ tissue and 0.16 ± 0.02 pieces g⁻¹ tissue, respectively. Contamination was quantified but not subtracted. Over …

Traditional Knowledge Of Fire Use By The Confederated Tribes Of Warm Springs In The Eastside Cascades Of Oregon, Michelle M. Steen-Adams, Susan Charnley, Rebecca Mclain, Mark D. O. Adams, Kendra L. Wendel

Institute for Sustainable Solutions Publications and Presentations

We examined traditional knowledge of fire use by the Ichishikin (Sahaptin), Kitsht Wasco (Wasco), and Numu (Northern Paiute) peoples (now Confederated Tribes of Warm Springs, CTWS) in the eastside Cascades of Oregon to generate insights for restoring conifer forest landscapes and enhancing culturally-valued resources. We examined qualitative and geospatial data derived from oral history interviews, participatory GIS focus groups, archival records, and historical forest surveys to characterize cultural fire regimes (CFRs) –an element of historical fire regimes– of moist mixed conifer (MMC), dry mixed conifer (DMC), and shrub-grassland (SG) zones. Our ethnohistorical evidence indicated a pronounced cultural fire regime in …

Watershed Assessment Of Tryon Creek Of Oregon, Danielle Goodrich

Environmental Science and Management Professional Master's Project Reports

As the Tryon Creek Watershed Council (TCWC) continues to grow its organization, it is important to focus their efforts on lasting changes that most positively affect the watershed. The TCWC plays a community-appointed role as the binding element of agency and stakeholder partnerships throughout the Tryon Creek watershed by providing communication and cooperation. The watershed assessment aims to provide a compilation of existing data as well as an identification of data gaps and recommendations for future cooperative management of the watershed. Developing an understanding of the processes that shape the watershed can shed light on the status of measurable ecosystem …

Data From: Microplastic Concentrations In Two Oregon Bivalve Species: Spatial, Temporal, And Species Variability, Britta Baechler, Elise F. Granek, Matthew V. Hunter, Kathleen E. Conn

Environmental Science and Management Datasets

Microplastics are an ecological stressor with implications for ecosystem and human health when present in seafood. We quantified microplastic types, concentrations, anatomical burdens, geographic distribution, and temporal differences in Pacific oysters (Crassostrea gigas) and Pacific razor clams (Siliqua patula) from 15 Oregon coast, U.S.A. sites. Organisms were chemically digested and visually analyzed for microplastics, and material type was determined using Fourier Transform Infrared Spectroscopy. Microplastics were present in organisms from all sites. On average, whole oysters and razor clams contained 10.95 ± 0.77 and 8.84 ± 0.45 microplastic pieces per individual, or 0.35 ± 0.04 and …

Nutrients Mediate The Effects Of Temperature On Methylmercury Concentrations In Freshwater Zooplankton, Meredith P. Jordan, A. Robin Stewart, Collin A. Eagles-Smith, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

Methylmercury (MeHg) bioaccumulation in freshwater aquatic systems is impacted by anthropogenic stressors, including climate change and nutrient enrichment. The goal of this study was to determine how warmer water temperatures and excess nutrients would alter zooplankton communities and phytoplankton concentrations, and whether those changes would in turn increase or decrease MeHg concentrations in freshwater zooplankton. To test this, we employed a 2 × 2 factorialexperimental design with nutrient and temperature treatments. Mesocosms were filled with ambient water and plankton from Cottage Grove Reservoir, Oregon, U.S.A., a waterbody that has experienced decades of elevated MeHg concentrations and …

Performance Of Genetic Distance Metrics In Gravity And General Mixed Effects Models, Nathan B. Alexander, Crysta Gantz, Jane L. Remfert, Melanie A. Murphy

Environmental Science and Management Faculty Publications and Presentations

There are many causes for the genetic patterns that arise among populations across a landscape. Effective population size, natal site preference, geographic distance, or barriers to gene flow associated with landscape composition may work in opposition or in concert resulting in varying degrees of population differentiation. Here, we simulate 40 populations under 3 different ecological hypotheses of individual dispersal with random mating for 1500 generations, with scenarios: 1) dispersal and mating is dependent on habitat between populations, 2) dispersal and mating is dependent on individuals finding habitat similar to their natal habitat, and 3) dispersal and mating is dependent on …

Monitoring Lesser Known Harmful Algal Blooms On The Oregon Coast, Taylor Dodrill, Tawnya D. Peterson, Matthew Hunter, Micah Rogers

OHSU-PSU School of Public Health Annual Conference

Ocean warming has expanded the niche of harmful algal blooms (HABs), including HABs previously believed to pose little risk of shellfish contamination in the Pacific Northwest. Monitoring efforts in Washington and California have demonstrated that Dinophysis spp. is a HAB of emerging concern and has been linked to diarrhetic shellfish poisoning events. However, quantitative monitoring for Dinophysis spp. on the Oregon Coast has been limited. This analysis provides a preliminary characterization of risk that Dinophysis spp. poses to shellfish consumers in Oregon. Furthermore, we assess the predator-prey interaction between Dinophysis spp. and its prey, Mesodinium rubrum, to determine whether …

Process-Based Modeling Of The Dairy Mckay Watershed To Inform Monitoring For Agricultural Best Management Practices, Brittany Saeman

Environmental Science and Management Professional Master's Project Reports

The project described in this paper specifically looks at the influence of land management practices on water quality, specifically total phosphorus (TP) loads in the Dairy McKay Watershed (DMW). The project is being used to inform a water quality monitoring plan for the Oregon DEQ via outputs from a SWAT model. The DMW is known to have high TP levels that are linked to low dissolved oxygen levels in the Tualatin River. There is a total maximum daily load (TMDL) for the Tualatin River that specifies target TP levels coming out of the DMW, if these targets are met, the …

Analysis Of Toxic Pollutant Sources And Characteristics Contributing To Water Quality Impairments In The Willamette River Basin, Melinda Borgens

Environmental Science and Management Professional Master's Project Reports

Point and nonpoint sources contribute toxic pollutants to surface waters, degrading water quality and impairing aquatic and human life. As of 2012, 51 stream segments totaling approximately 6,000 kilometers (3,750 miles) in Oregon’s Willamette River Basin (the Basin) were listed as impaired on the Clean Water Act's (CWA) Section 303(d) list with 48 toxic pollutants. These toxic pollutants exceed the Oregon Department of Environmental Quality's (DEQ) state water quality standards, requiring Total Maximum Daily Loads (TMDLs) to restore water quality and protect beneficial uses. Identifying toxic pollutant point and nonpoint sources, and the total loads a waterbody receives, are critical …

Farmer Attitudes Toward Cooperative Approaches To Herbicide Resistance Management: A Common Pool Ecosystem Service Challenge, David E. Ervin, Elise H. Breshears, George B. Frisvold, Terrance M. Hurley, Katherine E. Dentzman, Jeffrey L. Gunsolus, Raymond A. Jussaume, Micheal D. K. Owen, Jason Norsworthy, Mustofa Mahmud Al Mamun, Wesley Everman

Environmental Science and Management Faculty Publications and Presentations

Dramatic growth in herbicide-resistant (HR) weeds in the United States threatens farm profitability and may undercut environmentally beneficial farming practices. When HR weeds move across farm boundaries due to ecological processes or human action, a common pool resource challenge emerges, requiring farmer cooperation to manage such weeds effectively. We investigate the scope for cooperative management using responses to a national survey on HR weed issues to test a recursive model of three preconditions for collective action: (1) concern about HR weeds migrating from nearby lands; (2) communication with neighbors about HR weeds; and (3) belief that cooperation is necessary for …