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Environmental Science and Management Faculty Publications and Presentations

Series

2020

Articles 1 - 12 of 12

Full-Text Articles in Physical Sciences and Mathematics

From Forests To Fish: Mercury In Mountain Lake Food Webs Influenced By Factors At Multiple Scales, Ariana M. Chiapella, Collin A. Eagles-Smith, Angela L. Strecker Dec 2020

From Forests To Fish: Mercury In Mountain Lake Food Webs Influenced By Factors At Multiple Scales, Ariana M. Chiapella, Collin A. Eagles-Smith, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

Mountain lakes, while seemingly pristine, have been subjected to historical fish stocking practices and exposure to atmospherically deposited contaminants like mercury. Mercury bioaccumulation in these ecosystems varies widely due to strong environmental gradients, and there are complex, hierarchical factors that affect mercury transport and loading, methylmercury production, and food web biomagnification. We sought to assess how representative variables associated with watershed, lake, and food web-scale processes—specifically, catchment tree cover, lake benthic primary production, and fish diet, respectively—are associated with mercury concentrations in mountain lake fish. Mean fish mercury concentrations varied threefold between lakes, with nearshore tree cover and fish diet …


Projected Impact Of Mid-21st Century Climate Change On Wildfire Hazard In A Major Urban Watershed Outside Portland, Oregon Usa, Andy Mcevoy, Max Nielsen-Pincus, Andres Holz, Arielle J. Catalano, Kelly E. Gleason Dec 2020

Projected Impact Of Mid-21st Century Climate Change On Wildfire Hazard In A Major Urban Watershed Outside Portland, Oregon Usa, Andy Mcevoy, Max Nielsen-Pincus, Andres Holz, Arielle J. Catalano, Kelly E. Gleason

Environmental Science and Management Faculty Publications and Presentations

Characterizing wildfire regimes where wildfires are uncommon is challenged by a lack of empirical information. Moreover, climate change is projected to lead to increasingly frequent wildfires and additional annual area burned in forests historically characterized by long fire return intervals. Western Oregon and Washington, USA (westside) have experienced few large wildfires (fires greater than 100 hectares) the past century and are characterized to infrequent large fires with return intervals greater than 500 years. We evaluated impacts of climate change on wildfire hazard in a major urban watershed outside Portland, OR, USA. We simulated wildfire occurrence and fire regime characteristics under …


Microplastic Prevalence In Four Oregon Rivers Along A Rural To Urban Gradient Applying A Cost-Effective Validation Technique, Amy Valine, Ashley Peterson, Dorothy Horn, Kaegan M. Scully‐Engelmeyer, Elise F. Granek May 2020

Microplastic Prevalence In Four Oregon Rivers Along A Rural To Urban Gradient Applying A Cost-Effective Validation Technique, Amy Valine, Ashley Peterson, Dorothy Horn, Kaegan M. Scully‐Engelmeyer, Elise F. Granek

Environmental Science and Management Faculty Publications and Presentations

Microplastics are ubiquitous in our environment and are found in rivers, streams, oceans, and even tap water. Riverine microplastics are relatively understudied compared to those in marine ecosystems. In Oregon, we sampled eight sites along four freshwater rivers spanning rural to urban areas to quantify microplastics. Plankton tow samples from sites along the Columbia, Willamette, Deschutes, and Rogue Rivers were analyzed using traditional light microscopy for initial microplastic counts. Application of Nile Red dye to validate microplastics improved microplastic identification, particularly for particles (Wilcox Test; p‐value=0.001). Nile Red‐corrected microfiber abundance was correlated with human population within five kilometers of the …


Fatty Acid Stable Isotopes Add Clarity, But Also Complexity, To Tracing Energy Pathways In Aquatic Food Webs, Ariana M. Chiapella, Martin J. Kainz, Angela L. Strecker Feb 2020

Fatty Acid Stable Isotopes Add Clarity, But Also Complexity, To Tracing Energy Pathways In Aquatic Food Webs, Ariana M. Chiapella, Martin J. Kainz, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

Tracing the flow of dietary energy sources, especially in systems with a high degree of omnivory, is an ongoing challenge in ecology. In aquatic systems, one of the persistent challenges is in differentiating between autochthonous and allochthonous energy sources to top consumers. Bulk carbon stable isotope values of aquatic and terrestrial prey often overlap, making it difficult to delineate dietary energy pathways in food webs with high allochthonous prey subsidies, such as in many northern temperate waterbodies. We conducted a feeding experiment to explore how fatty acid stable isotopes may overcome the challenge of partitioning autochthonous and allochthonous energy pathways …


Centering Equity In Oregon’S 100 Year Water Vision: A Student-Led Policy Paper Prepared By The Oregon Water Stories Team At Portland State University, Clare T. Mcclellan, Sadie Boyers, Victoria Cali De Leon, Tony Cole, Laura Cowley-Martinson, Shersten Finley, Dustin Lanker, Julia Seydel, Aakash Nath Upraity, Janet Cowal, Melissa Haeffner Jan 2020

Centering Equity In Oregon’S 100 Year Water Vision: A Student-Led Policy Paper Prepared By The Oregon Water Stories Team At Portland State University, Clare T. Mcclellan, Sadie Boyers, Victoria Cali De Leon, Tony Cole, Laura Cowley-Martinson, Shersten Finley, Dustin Lanker, Julia Seydel, Aakash Nath Upraity, Janet Cowal, Melissa Haeffner

Environmental Science and Management Faculty Publications and Presentations

The purpose of this report is to provide evidence for the need to further intentionally incorporate equity into Oregon’s 100 Year Water Vision. Four case studies contextualize this need and highlight the variety of water issues throughout the state, supported by linguistic analyses of local newspapers. As Oregon policy-makers are responsible for ensuring working water systems for all Oregonians, we also suggest implementable criteria for the evaluation of equity in water issues and decision-making. This student-led and interdisciplinary report comes from the Haeffner-Cowal Oregon Water Stories research lab at Portland State University.


Microplastics In Aquatic Organisms: Improving Understanding And Identifying Research Directions For The Next Decade, Elise F. Granek, Susanne Brander, E. B. Holland Jan 2020

Microplastics In Aquatic Organisms: Improving Understanding And Identifying Research Directions For The Next Decade, Elise F. Granek, Susanne Brander, E. B. Holland

Environmental Science and Management Faculty Publications and Presentations

The study of environmental microplastics has increased over the past decade, with hundreds of new studies and resultant papers on the presence, fate, and sources of microplastics in marine and freshwater systems (Fig. 1). Despite the explosion of interest in the topic and in comparison to the research on the presence of microplastics in marine or fresh waters, there have been notably fewer studies on the extent to which these debris items are ingested by aquatic organisms and far fewer on the potential consequences, or response to their presence in organismal guts, tissues, and food webs. Even less research has …


Fire And Land Cover Change In The Palouse Prairie–Forest Ecotone, Washington And Idaho, Usa, Penelope Morgan, Emily K. Heyerdahl, Eva K. Strand, Stephen C. Bunting, James P. Riser Ii, John T. Abatzoglou, Max Nielsen-Pincus, Mara Johnson Jan 2020

Fire And Land Cover Change In The Palouse Prairie–Forest Ecotone, Washington And Idaho, Usa, Penelope Morgan, Emily K. Heyerdahl, Eva K. Strand, Stephen C. Bunting, James P. Riser Ii, John T. Abatzoglou, Max Nielsen-Pincus, Mara Johnson

Environmental Science and Management Faculty Publications and Presentations

Background: Prairie–forest ecotones are ecologically important for biodiversity and ecological processes. While these ecotones cover small areas, their sharp gradients in land cover promote rich ecological interaction and high conservation value. Our objective was to understand how historical and current fire occurrences and human development influenced the Palouse Prairie–forest ecotone. We used General Land Office survey field notes about the occurrence of bearing trees to locate historical (1870s to 1880s) prairie, pine savanna, and forest at the eastern edge of the bioregion. We combined LANDFIRE Existing Vegetation classes to contrast historical land cover with current land cover. We reconstructed …


Potential Greenhouse Gas Reductions From Natural Climate Solutions In Oregon, Usa, Rose A. Graves, Ryan D. Haugo, Andres Holz, Max Nielsen-Pincus, Aaron Jones, Bryce Kellogg, Cathy Macdonald, Kenneth Popper, Micheal Schindel Jan 2020

Potential Greenhouse Gas Reductions From Natural Climate Solutions In Oregon, Usa, Rose A. Graves, Ryan D. Haugo, Andres Holz, Max Nielsen-Pincus, Aaron Jones, Bryce Kellogg, Cathy Macdonald, Kenneth Popper, Micheal Schindel

Environmental Science and Management Faculty Publications and Presentations

Increasing concentrations of greenhouse gases (GHGs) are causing global climate change and decreasing the stability of the climate system. Long-term solutions to climate change will require reduction in GHG emissions as well as the removal of large quantities of GHGs from the atmosphere. Natural climate solutions (NCS), i.e., changes in land management, ecosystem restoration, and avoided conversion of habitats, have substantial potential to meet global and national greenhouse gas (GHG) reduction targets and contribute to the global drawdown of GHGs. However, the relative role of NCS to contribute to GHG reduction at subnational scales is not well known. We examined …


Using Diatoms To Assess River Restoration: A Pilot Study In Whychus Creek, Oregon, Usa, Patrick M. Edwards, Yangdong Pan, Lauren Mork, Colin R. Thorne Jan 2020

Using Diatoms To Assess River Restoration: A Pilot Study In Whychus Creek, Oregon, Usa, Patrick M. Edwards, Yangdong Pan, Lauren Mork, Colin R. Thorne

Environmental Science and Management Faculty Publications and Presentations

A primary goal of river restoration is to reestablish lost ecological functions. Yet the impact of restoration on diatom assemblages and algal biomass in a stream is rarely addressed in the scientific literature reporting the outcomes of restoration projects aimed at improving riverine habitat. To investigate the potential for using benthic diatoms as indicators of the benefits to habitat associated with river restoration, we conducted a pilot diatom study in Whychus Creek, a headwater tributary of the Deschutes River in Oregon, USA. As part of a work study project for college students, we collected periphyton samples in a restored reach, …


Microplastic Exposure By Razor Clam Recreational Harvester-Consumers Along A Sparsely Populated Coastline, Britta Baechler, Scott J. Mazzone, Elise F. Granek, Max Nielsen-Pincus, Susanne Brander Jan 2020

Microplastic Exposure By Razor Clam Recreational Harvester-Consumers Along A Sparsely Populated Coastline, Britta Baechler, Scott J. Mazzone, Elise F. Granek, Max Nielsen-Pincus, Susanne Brander

Environmental Science and Management Faculty Publications and Presentations

Microplastics (MPs) are anthropogenic contaminants found in coastal and marine environments worldwide. Pacific razor clams (Siliqua patula), important for local indigenous culture, economy, gastronomy and food security along the United States West Coast, are subjected to myriad environmental stressors including predation, storm events, disease, toxins, and MPs. This study aimed to determine MP burdens in Olympic Coast, Washington Pacific razor clams and estimate annual MP exposure of recreational razor clam harvester-consumers from eating this species. We quantified suspected MP burdens in Pacific razor clams collected from eight tribal, recreational, and commercial harvest areas on the Olympic Coast in April 2018. …


Assessment Of Multi-Stressors On Compositional Turnover Of Diatom, Invertebrate And Fish Assemblages Along An Urban Gradient In Pacific Northwest Streams (Usa), Ian Waite, Yangdong Pan, Patrick M. Edwards Jan 2020

Assessment Of Multi-Stressors On Compositional Turnover Of Diatom, Invertebrate And Fish Assemblages Along An Urban Gradient In Pacific Northwest Streams (Usa), Ian Waite, Yangdong Pan, Patrick M. Edwards

Environmental Science and Management Faculty Publications and Presentations

This study is part of the regional stream-quality assessment (RSQA) conducted by the U.S. Geological Survey (USGS) National Water Quality Assessment (NAWQA) project. The purpose of this study is to examine small streams along land-use and stressor gradients at the regional scale and to evaluate the relative importance of instream stressors on diatom, macroinvertebrate, and fish assemblages. In 2015, the RSQA project assessed stream quality in 82 wadeable streams that were selected along an urban land-use gradient in the Pacific Northwest Region (PNW) of the United States. This study evaluates the effects of four major categories of measured instream stressors …


Food Waste Knowledge, Attitudes, And Behavioral Intentions Among University Students, Manar Arica Alattar, James Delaney, Jennifer L. Morse, Max Nielsen-Pincus Jan 2020

Food Waste Knowledge, Attitudes, And Behavioral Intentions Among University Students, Manar Arica Alattar, James Delaney, Jennifer L. Morse, Max Nielsen-Pincus

Environmental Science and Management Faculty Publications and Presentations

After policy change, educational programming has been cited as one of the most powerful tools for improving food systems and decreasing food waste. University students represent a population in which emerging habits, skills, and identity may be targeted easily and changed through on-campus educational programming. To understand how to best implement programming on impacts of food, food waste, and related issues, the factors that underlie students’ behaviors related to food waste must be understood. We analyzed factors that influence food waste–related behaviors within a university student population to understand the potential for improving targeted, school-based food waste diversion programming. Four …