Digital Commons Network^™

Mussel Squeeze: Dissolved Oxygen And Temperature Can “Squeeze” Zebra Mussels Out Of Invaded Reservoirs, Crysta Gantz, Rich Miller, Steve Wells, Mark D. Sytsma, Angela Strecker

Environmental Science and Management Faculty Publications and Presentations

Zebra mussels (Dreissena polymorpha) are an aquatic invasive species that cause extensive economic and ecological impacts and are a management priority in areas outside of their native range. Survivorship and distribution of zebra mussels within a waterbody are thought to be influenced by temperature and dissolved oxygen conditions, but detailed information to confirm the importance of these environmental controls is necessary to inform management efforts. We measured planktonic zebra mussel veliger density and adult survivorship in San Justo Reservoir in central California to determine distribution and timing of spawning in relation to temperature and dissolved oxygen throughout winter, spring, and …

Spatial Validation Of Agent-Based Models, Kristoffer Wikstrom, Hal T. Nelson

Public Administration Faculty Publications and Presentations

This paper adapts an existing techno–social agent-based model (ABM) in order to develop a new framework for spatially validating ABMs. The ABM simulates citizen opposition to locally unwanted land uses, using historical data from an energy infrastructure siting process in Southern California. Spatial theory, as well as the model’s design, suggest that adequate validation requires multiple tests rather than relying solely on a single test-statistic. A pattern-oriented modeling approach was employed that first mapped real and simulated citizen comments across the US Census tract. The suite of spatial tests included Global Moran’s I, complemented with bivariate correlations, as well as …

Climate Change Curricula In Alberta, Canada: An Intersectional Framing Analysis, Greg Lowan-Trudeau

Northwest Journal of Teacher Education

This article is comprised of a climate change-focused framing analysis of proposed revisions to Alberta, Canada’s K-6 curriculum as an ideologically motivated manifestation of curricular epistemicide. Eisner’s three curricula—the explicit, implicit, and null—and scholarship related to intersectional climate and environmental justice, education, and communication provide the theoretical framework. This inquiry concludes with a critical discussion of and possible alternatives to the revised curriculum with further consideration of the implications for those involved with similar endeavours in other jurisdictions across Canada and around the world.

Response Of Soil Respiration To Changes In Soil Temperature And Water Table Level In Drained And Restored Peatlands Of The Southeastern United States, E. E. Swails, K. Krauss, Marcelo Ardón, A. L. Peralta, A. M. Helton, Jennifer L. Morse, Multiple Additional Authors

Environmental Science and Management Faculty Publications and Presentations

Background

Extensive drainage of peatlands in the southeastern United States coastal plain for the purposes of agriculture and timber harvesting has led to large releases of soil carbon as carbon dioxide (CO2) due to enhanced peat decomposition. Growth in mechanisms that provide financial incentives for reducing emissions from land use and land-use change could increase funding for hydrological restoration that reduces peat CO2 emissions from these ecosystems. Measuring soil respiration and physical drivers across a range of site characteristics and land use histories is valuable for understanding how CO2 emissions from peat decomposition may respond to raising water table levels. …

The Consequential Role Of Aesthetics In Forest Fuels Reduction Propensities: Diverse Landowners’ Attitudes And Responses To Project Types, Risks, Costs, And Habitat Benefits, Robert G. Ribe, Max Nielsen-Pincus, Chris Enright, Bart R. Johnson, David Hulse

Environmental Science and Management Faculty Publications and Presentations

Private landowners in the southern Willamette Valley of Oregon, USA were surveyed. The survey queried probabilities of implementing specific fuels reduction projects in extensive areas of specific forest types on their property. The projects were described in relation to the beginning and target forest types, the actions required, costs, and long-term maintenance. Forest types were first rated for scenic beauty and informed levels of wildfire risk reduction, scarce habitat production, and associated property rights risks. Propensities to perform each fuels reduction project were then obtained. These were adversely affected by disbelief in heightened wildfire risks or climate change, higher project …

River Discharge Mediates Extent Of Phytoplankton And Harmful Algal Bloom Habitat In The Columbia River Estuary (Usa) During North Pacific Marine Heat Waves, Taylor N. Dodrill, Yangdong Pan, Tawnya D. Peterson

Environmental Science and Management Faculty Publications and Presentations

Marine heat waves (MHWs) have been associated with extensive harmful algal blooms (HABs) in the northeast Pacifc Ocean, but the degree to which these large-scale oceanographic events are mirrored in nearshore environments has not been well established. We compared phytoplankton assemblages in the Lower Columbia River Estuary (LCRE) during two Pacifc MHWs that took place in 2015 and 2019, with observations from 2017, a year with no MHW. These data were paired with environmental data from the summers of 2015–2019 to characterize differences in estuarine conditions during MHWs that promote phytoplankton assemblage transitions and identify HAB-conducive conditions. Bloom densities of …

Herbicide-Resistance In Turf Systems: Insights And Options For Managing Complexity, Jennifer H. Allen, David Ervin, George Frisvold, James T. Brosnan, James D. Mccurdy, Rebecca G. Bowling, Aaron J. Patton, Matthew T. Elmore, Travis W. Gannon, Lambert B. Mccarty, Multiple Additional Authors

Public Administration Faculty Publications and Presentations

Due to complex interactions between social and ecological systems, herbicide resistance has classic features of a “wicked problem.” Herbicide-resistant (HR) Poa annua poses a risk to sustainably managing U.S. turfgrass systems, but there is scant knowledge to guide its management. Six focus groups were conducted throughout the United States to gain understanding of socio-economic barriers to adopting herbicide-resistance management practices. Professionals from major turfgrass sectors (golf courses, sports fields, lawn care, and seed/sod production) were recruited as focus-group participants. Discussions emphasized challenges of the weed management of turfgrass systems as compared to agronomic crops. This included greater time constraints for …

Towards More Equitable And Climate Resilient Communities With Jola Ajibade, Jola Ajibade

PDXPLORES Podcast

In this episode of PDXPLORES, Professor Jola Ajibade discusses research examining how cascading social and environmental hazards might impact communities in the Portland metro region and what policymakers and community members can do to mitigate the risks and promote a more just, livable, and sustainable urban future.

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Warming Of The Willamette River, 1850–Present: The Effects Of Climate Change And Direct Human Interventions, Stefan Talke, David Jay, Heida Diefenderfer

Civil and Environmental Engineering Faculty Publications and Presentations

Using archival research methods, we found and combined data from multiple sources to produce a unique, 140 year record of daily water temperature (Tw) in the lower Willamette River, Oregon (1881–1890, 1941–present). Additional daily weather and river flow records from the 1850s onwards are used to develop and validate a statistical regression model of Tw for 1850–2020. The model simulates the time-lagged response of Tw to air temperature and river flow, and is calibrated for three distinct time periods: the late 19th, mid 20th, and early 21st centuries. Results show that Tw has trended upwards at ~1.1 °C …

Ecological Homogenization Of Oil Properties In The American Residential Macrosystem, Christopher D. Ryan, Peter M. Groffman, J. Morgan Grove, Sharon J. Hall, James B. Heffernan, Sarah E. Hobbie, Dexter H. Locke, Jennifer L. Morse, Rinku Roy Chowdhury, Tara Trammell, Multiple Additional Authors

Environmental Science and Management Faculty Publications and Presentations

The conversion of native ecosystems to residential ecosystems dominated by lawns has been a prevailing land-use change in the United States over the past 70 years. Similar development patterns and management of residential ecosystems cause many characteristics of residential ecosystems to be more similar to each other across broad continental gradients than that of former native ecosystems. For instance, similar lawn management by irrigation and fertilizer applications has the potential to influence soil carbon (C) and nitrogen (N) pools and processes. We evaluated the mean and variability of total soil C and N stocks, potential net N mineralization and nitrification, …

Predicting Springtime Herbicide Exposure Across Multiple Scales In Pacific Coastal Drainages (Oregon, Usa), Kaegan Michael Scully-Engelmeyer, Elise F. Granek

Environmental Science and Management Faculty Publications and Presentations

Identification of non-point sources of watershed pollution such as pesticide runoff is challenging due to spatial and temporal variation in landscape patterns of land use and environmental conditions. Regional case study monitoring investigations can document region-specific conditions and processes to inform managers about pesticide movement through watersheds. Additionally, modeling field-collected data within these contexts can be used to predict pesticide presence in un-sampled areas. During a 45 day period in the spring of 2019, we sampled sixteen coastal watersheds in Oregon, USA for current-use water-borne herbicides commonly used in forestland vegetation management. At 80 % of sampling locations, at least …

Forest Fire Effects On Landscape Snow Albedo Recovery And Decay, Max Gersh, Kelly E. Gleason, Anton Surunis

Environmental Science and Management Faculty Publications and Presentations

Surface snow albedo (SSA) darkens immediately following a forest fire, while landscape snow albedo (LSA) brightens as more of the snow-covered surface becomes visible under the charred canopy. The duration and variability of the post-fire snow albedo recovery process remain unknown beyond a few years following the fire. We evaluated the temporal variability of post-fire snow albedo recovery relative to burn severity across a chronosequence of eight burned forests burned from 2000 to 2019, using pre- and post-fire daily, seasonal, and annual landscape snow albedo data derived from the Moderate Resolution Imaging Spectroradiometer (MOD10A1). Post-fire annual LSA increased by 21% …

On Capturing Human Agency And Methodological Interdisciplinarity In Socio-Hydrology Research, David J. Yu, Melissa Haeffner, Hanseok Jeong, Saket Pande, Juliane Dame, Giuliano Di Baldassarre, Glenda Garcia-Santos, Leon Hermans, Rashata Muneepeerakul, Multiple Additional Authors

Environmental Science and Management Faculty Publications and Presentations

Socio-hydrology has expanded and been effective in exposing the hydrological community to ideas and approaches from other scientific disciplines, and social sciences in particular. Yet it still has much to explore regarding how to capture human agency and how to combine different methods and disciplinary views from both the hydrological and the social sciences to develop knowledge. A useful starting ground is noting that the complexity of human–water relations is due to interactions not only across spatial and temporal scales but also across different organizational levels of social systems. This calls for consideration of another analytical scale, the human organizational …

Understanding Water Security In Portland, Oregon: Using Newspapers As Tools For Science Communication And Education, Julian Roth

University Honors Theses

Water insecurity is faced by a large percentage of the global population, particularly in urban areas, which face greater and more complex needs for water resources. Better tools are needed to be able to recognize and communicate water security issues in a way that reinforces water systems, engages all stakeholders, and recognizes early warnings of environmental injustice. This research examines utilizing public newspaper articles to produce these tools. Using a case-study approach, this thesis explores newspaper articles about water from 2014-2020 in the urban center of Portland, Oregon, to understand local water security issues and to build a system of …

Equilibria: Sustainability And Eco-Awareness In Music Production, Ashley A. Kahl-Placek

University Honors Theses

Cross-disciplinary exploration between science and the arts is one tool to help solve some of the biggest issues facing humans. Climate change and loss of biodiversity can be represented via sound art and contemporary music composition. Wholistic eco-awareness and sustainability are possible when projects are based in unique species-inspired soundscapes, the cultivation of targeted, action-inspiring lyricism, and a sustainable navigation of the marketing and distribution pathways of the music industry. From the fall of 2021 to summer of 2022, field recordings of unique ecosystems were collected and combined with songwriting rooted in a love and hope for the future of …

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 …

Standardized Neon Organismal Data For Biodiversity Research, Daijiang Li, Sydne Record, Eric R. Sokol, Matthew E. Bitters, Melissa Y. Chen, Ruvi Jaimes, Matthew R. Helmus, Lara Jansen, Marta A. Jarzyna, Multiple Additional Authors

Environmental Science and Management Faculty Publications and Presentations

Understanding patterns and drivers of species distribution and abundance, and thus biodiversity, is a core goal of ecology. Despite advances in recent decades, research into these patterns and processes is currently limited by a lack of standardized, high-quality, empirical data that span large spatial scales and long time periods. The NEON fills this gap by providing freely available observational data that are generated during robust and consistent organismal sampling of several sentinel taxonomic groups within 81 sites distributed across the United States and will be collected for at least 30 years. The breadth and scope of these data provide a …

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, …

Drivers Of Spatiotemporal Eukaryote Plankton Distribution In A Trans-Basin Water Transfer Canal In China, Yuying Li, Faisal Hayat Khan, Jiamin Wu, Yun Zhang, Yeqing Jiang, Xiaonuo Chen, Yinlei Yao, Yangdong Pan, Xuemei Han

Environmental Science and Management Faculty Publications and Presentations

Planktonic eukaryotes are important components of aquatic ecosystems, and analyses of the whole eukaryotic planktonic community composition and function have far-reaching significance for water resource management. We aimed to understand the spatiotemporal variation and drivers of eukaryotic plankton distribution in the Middle Route Project of the South-to-North Water Diversion in Henan Province, China. Specifically, we examined planktonic assemblages and water quality at five stations along the canal and another one located before the dam in March, June, September, and December 2019. High-throughput sequencing revealed that the eukaryotic plankton community was primarily composed of 53 phyla, 200 genera, and 277 species, …

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 …

The Impact Of Human Activity On Coastal Zones With Elise Granek, Elise F. Granek

PDXPLORES Podcast

In this episode of PDXPLORES, Professor Elise Granek discusses the coastal zone- transition zones between land, sea, and atmosphere. These ecosystems provide vital ecological, cultural, and commercial benefits. Around the world, they are home to a vast number of species, support critical industries, and sustain the cultural heritage of the people who have called them home. As with all ecosystems, they are vulnerable. Given the intense human dependence on the continued viability of these coastal ecosystems, understanding the impact of human activity on the species that inhabit them is essential to identifying solutions to address the suite of impacts. What …

Using An Affinity Analysis To Identify Phytoplankton Associations, Weiju Zhu, Zhaojian Ding, Yangdong Pan, Quanxi Wang

Environmental Science and Management Faculty Publications and Presentations

Phytoplankton functional traits can represent particular environmental conditions in complex aquatic ecosystems. Categorizing phytoplankton species into functional groups is challenging and time-consuming, and requires high-level expertise in species autecology. In this study, we introduced an affinity analysis to aid the identification of candidate associations of phytoplankton from two data sets comprised of phytoplankton and environmental information. In the Huaihe River Basin with a drainage area of 270,000 km2 in China, samples were collected from 217 selected sites during the low-water period in May 2013; monthly samples were collected during 2006–2011 in a man-made pond, Dishui Lake. Our results indicated that …

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 …

Can Diatom Motility Indices Reflect Excess Fine Sediment Condition In Streams?, Christine L. Weilhoefer, Yangdong Pan

Environmental Science and Management Faculty Publications and Presentations

The diatom motility trait is widely used in bioassessment studies, however, there is no strong consensus as to what environmental conditions diatom motility reflects. We used random forest models to explore the behavior of several diatom-based motility indices and examined whether stronger diatom motility-environmental relationships could be developed by controlling for environmental factors that influence natural sediment loads and factors that co-occur with anthropogenic sediment loading. Across the study area, median values of most stressors were low; streambed fine sediments ranged from 0 to 100% (median: 6.7%) and total phosphorus concentrations ranged from 0 to 2587 µg L−1 (median: 17 …

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 …

"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 …

Ecosystem Connectivity For Livable Cities: A Connectivity Benefits Framework For Urban Planning, Carole Hardy, Catherine De Rivera, Leslie Bliss-Ketchum, Eric P. Butler, Sahan Dissanayake, Dorothy A. Horn, Ben Huffine, Amanda M. Temple, Michael Vermeulen, Hailey Wallace, Jennifer Michelle Karps

Environmental Science and Management Faculty Publications and Presentations

Urbanization disrupts landscapes and ecosystem functions, which poses threats to biodiversity, social systems, and human health, particularly among vulnerable populations. Urban land-use planners are faced with competing demands for housing, safety, transportation, and economic development and often lack tools to integrate these with protecting environmental functions. We identify three major barriers to integrating the benefits that flow with connected, functioning ecosystems into land-use planning. The lack of a shared language among planners and stakeholders poses a barrier to the restoration and preservation of ecological features. Methods of incorporating the benefits from connectivity are not standardized because values are not readily …

Understanding Ch4 Emissions From Compostables: An Exploration Of Local Ch4 Emissions From Landfilled Compostables And The Efficacy Of Emission Mitigation Via Anaerobic Biogas Digestion, Jordan-Yoosuf Aljbour

University Honors Theses

Methane (CH₄) is the second most abundant anthropogenic greenhouse gas within the atmosphere, comprising ~16% of the total anthropogenic greenhouse gas composition on Earth. It has an ~12-year lifetime relative to its eventual oxidation via reaction with tropospheric hydroxyl radicals (OH), and has a 100-year indirect global warming potential (GWP) approximately ranging between 28-36 [Environmental Protection Agency, 2021]. In recent years, the observed average global concentration of atmospheric CH₄ has increased by ~11.0% from 2020 (~15.3 ppb) to 2021 (~17.0 ppb) [Dlugokencky et al., 1994; National Oceanic and Atmospheric Administration, 2022]. With …