Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Environmental Monitoring

2019

Portland State University

Keyword
Publication
Publication Type

Articles 1 - 12 of 12

Full-Text Articles in Physical Sciences and Mathematics

Effects Of Environmentally Relevant Concentrations Of Microplastic Fibers On Pacific Mole Crab (Emerita Analoga) Mortality And Reproduction, Dorothy Horn, Elise F. Granek, Clare Steele Dec 2019

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 Nov 2019

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 Oct 2019

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 Oct 2019

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 Jul 2019

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 Jun 2019

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 Apr 2019

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 Apr 2019

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 Apr 2019

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 Apr 2019

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 Mar 2019

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 …


Improved Drought Resilience Through Continuous Water Service Monitoring And Specialized Institutions—A Longitudinal Analysis Of Water Service Delivery Across Motorized Boreholes In Northern Kenya, Nick Turman-Bryant, Corey L. Nagel, Lauren Stover, Christian Muragijimana, Evan A. Thomas Jan 2019

Improved Drought Resilience Through Continuous Water Service Monitoring And Specialized Institutions—A Longitudinal Analysis Of Water Service Delivery Across Motorized Boreholes In Northern Kenya, Nick Turman-Bryant, Corey L. Nagel, Lauren Stover, Christian Muragijimana, Evan A. Thomas

Systems Science Faculty Publications and Presentations

Increasing frequency and severity of drought is driving increased use of groundwater resources in arid regions of Northern Kenya, where approximately 2.5 million people depend on groundwater for personal use, livestock, and limited irrigation. As part of a broader effort to provide more sustainable water, sanitation, and hygiene services in the region, we have collected data related to site functionality and use for approximately 120 motorized boreholes across five counties. Using a multilevel model to account for geospatial and temporal clustering, we found that borehole sites, which counties had identified as strategic assets during drought, ran on average about 1.31 …