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Effect Of Spatial Influence On Endophyte Diversity Within Alnus Rubra, Sebastian L. Singleton May 2017

Effect Of Spatial Influence On Endophyte Diversity Within Alnus Rubra, Sebastian L. Singleton

Student Research Symposium

Red alders (Alnus rubra) of the Pacific Northwest are characterized as actinorhizal dicotyledons; plants that possess that ability to form symbiotic relationships with endophytic organisms, which result in nitrogen-fixing nodules. In Alders of the order Fagales, such a symbiotic relationship with Frankia bacteria allows these plants to play crucial environmental roles as pioneer species able to colonize and enrich nutrient-deficient soils. This ability has a major impact on ecological succession by enabling other species to establish. Although inoculation with frankia bacteria is known to increase symbiotic nitrogen fixation capabilities of actinorhizal plants, whether they could confer the same benefit to …


A Four Year Study Of The Effects Of Substrate Depth On The Survival Of Different Plant Species In Portland, Or, Arjun Viray May 2017

A Four Year Study Of The Effects Of Substrate Depth On The Survival Of Different Plant Species In Portland, Or, Arjun Viray

Student Research Symposium

The changes in green roof plant species composition was observed after a four year time period. Twelve plots were planted in either native or non-native species at two different substrate depths according to a 2 by 2 factorial design. The list of original species from installation was used to identify which species survived over time in their respective plots. After four years, 9 out of 12 native species and 13 out of 14 species survived. The high survival of 26 original species must be compared to the colonization of 68 new species. With minimal maintenance, new species colonized plots. Extensive …


The Importance Of Urban Habitat Connectivity And Influence On Native Avian Species And Community Science, Kristen S. Gulick May 2017

The Importance Of Urban Habitat Connectivity And Influence On Native Avian Species And Community Science, Kristen S. Gulick

Student Research Symposium

In what ways do small-scale urban backyards contribute to local bird abundance and biodiversity? In what ways might these yards serve as an ‘extension’ of neighboring native forest areas? This project investigates the contribution that a group of backyards, certified through the Backyard Habitat Certification Program, have in the suburb of Hillsdale, Oregon, which is adjacent to the natural area of Keller Woodland. Backyard owners functioning as citizen or community scientists assisted with conducting residential bird point-counts once a week in each backyard and the natural area. Counts were done for a total of 8 weeks during nesting season to …


Gas Transfer Velocities In Small Forested Ponds, Meredith A. Holgerson, Emily R. Farr, Peter A. Raymond May 2017

Gas Transfer Velocities In Small Forested Ponds, Meredith A. Holgerson, Emily R. Farr, Peter A. Raymond

Environmental Science and Management Faculty Publications and Presentations

Inland waters actively exchange gases with the atmosphere, and the gas exchange rate informs system biogeochemistry, ecology, and global carbon budgets. Gas exchange in medium- to large-sized lakes is largely regulated by wind; yet less is known about processes regulating gas transfer in small ponds where wind speeds are low. In this study, we determined the gas transfer velocity, k600, in four small ( < 250 m2 ) ponds by using a propane ( C3H8 ) gas injection. When estimated across 12 h periods, the average k600 ranged from 0.19 to 0.72 m d-1 across …


Environmental Dna (Edna) Detects The Invasive Crayfishes Orconectes Rusticus And Pacifastacus Leniusculus In Large Lakes Of North America, Eric R. Larson, Mark A. Renshaw, Crysta Gantz, John Umek, Sudeep Chandra, David M. Lodge, Scott P. Egan May 2017

Environmental Dna (Edna) Detects The Invasive Crayfishes Orconectes Rusticus And Pacifastacus Leniusculus In Large Lakes Of North America, Eric R. Larson, Mark A. Renshaw, Crysta Gantz, John Umek, Sudeep Chandra, David M. Lodge, Scott P. Egan

Environmental Science and Management Faculty Publications and Presentations

We report results of a study that made reciprocal comparisons of environmental DNA (eDNA) assays for two major invasive crayfishes between their disparate invasive ranges in North America. Specifically, we tested for range expansions of the signal crayfish Pacifastacus leniusculus (Dana, 1852) into the Laurentian Great Lakes region known to be invaded by the rusty crayfish Orconectes rusticus (Girard, 1852), as well as for the invasion of O. rusticus into large lakes of California and Nevada, US known to be invaded by P. leniusculus. We compared eDNA detections to historic localities for O. rusticus within the Great Lakes, and to …


Assembly 2017, Portland State University Art And Social Practice Apr 2017

Assembly 2017, Portland State University Art And Social Practice

Assembly

Assembly 2017 took place in 3 locations connected to the Columbia River Slough


Power Dynamics And Environmental Resource Flows In The Network Society: Water Bottling And Policy Development In The Columbia Gorge, Cody Shotola-Schiewe Mar 2017

Power Dynamics And Environmental Resource Flows In The Network Society: Water Bottling And Policy Development In The Columbia Gorge, Cody Shotola-Schiewe

University Honors Theses

This research explores the sociopolitical development of resource rights policy and environmental resource flows in the network society. The specific interaction studied is centered on a disputed proposal by Nestlé Waters North America to the City of Cascade Locks, on the Oregon side of the Columbia River, which would allow Nestlé to build a water bottling plant accessing the culturally and environmentally significant Oxbow Springs. The primary question guiding this research is: In the case of the developing policy concerning water rights in the County of Hood River, what are the identifiable power dynamics between civil society actors, private interests, …


Urban Ecology & Conservation Symposium 2017: 15th Annual (Abstracts), Urban Ecosystem Research Consortium Of Portland/Vancouver Feb 2017

Urban Ecology & Conservation Symposium 2017: 15th Annual (Abstracts), Urban Ecosystem Research Consortium Of Portland/Vancouver

Urban Ecosystem Research Consortium of Portland/Vancouver

The UERC is a consortium of people from various universities and colleges, state and federal agencies, local governments, non-profit organizations and independent professionals interested in supporting urban ecosystem research and creating an information-sharing network of people that collect and use ecological data in the Portland/Vancouver area.

UERC Mission Statement:

To advance the state of the science of urban ecosystems and improve our understanding of them, with a focus on the Portland/Vancouver metropolitan region, by fostering communication and collaboration among researchers, managers and citizens at academic institutions, public agencies, local governments, non-profit organizations, and other interested groups.

The principal organizers span …


Improving Trip Generation Methods For Livable Communities, Kelly J. Clifton, Nico Larco, Kristina Marie Currans, Jael Wettach-Glosser Feb 2017

Improving Trip Generation Methods For Livable Communities, Kelly J. Clifton, Nico Larco, Kristina Marie Currans, Jael Wettach-Glosser

TREC Final Reports

Recent efforts to improve trip generation data available for transportation impact analysis of new development include the collection of multimodal trip generation data, development of models that account for the built environment, and new recommendations for practice. Building on a long line of research on transportation and built environment, many studies have identified important features of the surrounding built environment that most impact trip rates and mode shares, building on a long line of research on transportation and the built environment. Despite these improvements in data and methods, less attention is placed on identifying the conditions of the site itself …


Passive Warming Reduces Stress And Shifts Reproductive Effort In The Antarctic Moss, Polytrichastrum Alpinum, Erin E. Shortlidge, Sarah M. Eppley, Hans Kohler, Todd N. Rosenstiel, Gustavo E. Zúñiga, Angélica Casanova-Katny Jan 2017

Passive Warming Reduces Stress And Shifts Reproductive Effort In The Antarctic Moss, Polytrichastrum Alpinum, Erin E. Shortlidge, Sarah M. Eppley, Hans Kohler, Todd N. Rosenstiel, Gustavo E. Zúñiga, Angélica Casanova-Katny

Biology Faculty Publications and Presentations

Background and Aims: The Western Antarctic Peninsula is one of the most rapidly warming regions on Earth, and many biotic communities inhabiting this dynamic region are responding to these well-documented climatic shifts. Yet some of the most prevalent organisms of terrestrial Antarctica, the mosses, and their responses to warming have been relatively overlooked and understudied. In this research, the impacts of 6 years of passive warming were investigated using open top chambers (OTCs), on moss communities of Fildes Peninsula, King George Island, Antarctica.

Methods: The effects of experimental passive warming on the morphology, sexual reproductive effort and stress physiology of …


Unmanned Aerial Vehicle Based Structure From Motion Biomass Inventory Estimates, Emily Jane Bedell Dec 2016

Unmanned Aerial Vehicle Based Structure From Motion Biomass Inventory Estimates, Emily Jane Bedell

Dissertations and Theses

Riparian vegetation restoration efforts demand cost effective, accurate, and replicable impact assessments. In this thesis a method is presented using an Unmanned Aerial Vehicle (UAV) equipped with a GoPro digital camera to collect photogrammetric data of a 2.02-acre riparian restoration. A three-dimensional point cloud was created from the photos using Structure from Motion (SfM) techniques. The point cloud was analyzed and compared to traditional, ground-based monitoring techniques. Ground truth data collected using the status-quo approach was collected on 6.3% of the study site and averaged across the entire site to report stem heights in stems/acre in three height classes, 0-3 …


Winds Of Change? Exploring Climate Change-Driven Migration And Related Impacts In The Pacific Northwest, Lara Whitely Binder, Jason R. Jurjevich Dec 2016

Winds Of Change? Exploring Climate Change-Driven Migration And Related Impacts In The Pacific Northwest, Lara Whitely Binder, Jason R. Jurjevich

Publications, Reports and Presentations

Climate change is expected to have significant impacts on the Pacific Northwest’s communities, economy, and natural systems. These impacts – which include reductions in summer water supply, the potential for more winter flooding and forest fires, threats to public health, and damage to coastal infrastructure due to sea level rise – will require changes in how communities evaluate, manage, and mitigate environmental risks.

Despite these challenges, some have suggested that the region may be relatively well off compared to other areas of the U.S. and the world. This has led to growing speculation by the media, bloggers, and the public …


Adaptions: Mindful Living In The New Millenium (Full Issue) Nov 2016

Adaptions: Mindful Living In The New Millenium (Full Issue)

PSU McNair Scholars Online Journal

No abstract provided.


Enso Controls Interannual Fire Activity In Southeast Australia, Michela Mariani, Michael-Shawn Fletcher, Andrés Holz, Petter Nyman Oct 2016

Enso Controls Interannual Fire Activity In Southeast Australia, Michela Mariani, Michael-Shawn Fletcher, Andrés Holz, Petter Nyman

Geography Faculty Publications and Presentations

El Niño–Southern Oscillation (ENSO) is the main mode controlling the variability in the ocean-atmosphere system in the South Pacific. While the ENSO influence on rainfall regimes in the South Pacific is well documented, its role in driving spatiotemporal trends in fire activity in this region has not been rigorously investigated. This is particularly the case for the highly flammable and densely populated southeast Australian sector, where ENSO is a major control over climatic variability. Here we conduct the first region-wide analysis of how ENSO controls fire activity in southeast Australia. We identify a significant relationship between ENSO and both fire …


Use Of Water Indices Derived From Landsat Oli Imagery And Gis To Estimate The Hydrologic Connectivity Of Wetlands In The Tualatin River National Wildlife Refuge, Debra Sue Blackmore Aug 2016

Use Of Water Indices Derived From Landsat Oli Imagery And Gis To Estimate The Hydrologic Connectivity Of Wetlands In The Tualatin River National Wildlife Refuge, Debra Sue Blackmore

Dissertations and Theses

This study compared two remote sensing water indices: the Normalized Difference Water Index (NDWI) and the Modified NDWI (MNDWI). Both indices were calculated using publically-available data from the Landsat 8 Operational Land Imager (OLI). The research goal was to determine whether the indices are effective in locating open water and measuring surface soil moisture. To demonstrate the application of water indices, analysis was conducted for freshwater wetlands in the Tualatin River Basin in northwestern Oregon to estimate hydrologic connectivity and hydrological permanence between these wetlands and nearby water bodies. Remote sensing techniques have been used to study wetlands in recent …


Watershed Response To Climate Change And Fire-Burns In The Upper Umatilla River Basin Using The Precipitation Runoff Modeling System, Kimberly Crystal Yazzie Aug 2016

Watershed Response To Climate Change And Fire-Burns In The Upper Umatilla River Basin Using The Precipitation Runoff Modeling System, Kimberly Crystal Yazzie

Dissertations and Theses

This study provides an analysis of watershed response to climate change and forest fire impacts, to better understand the hydrologic budget and inform water management decisions for present and future needs. The study site is 2,365 km2, located in the upper Umatilla River Basin (URB) in northeastern Oregon. The Precipitation Runoff Modeling System, a distributed-parameter, physical-process watershed model, was used in this study. Model calibration yielded a Nash Sutcliffe Model Efficiency of 0.73 for both calibration (1995-2010) and validation (2010-2014) of daily streamflow. Ten Global Climate Models using Coupled Model Intercomparison Project Phase 5 experiments with Representative Concentration …


Aspirational Planning: A Statistical Model Of Hawthorne Bridge And Tilikum Crossing Bicycle Ride Counts, Robert Mccullough, Ramon Cabauatan, Jacob Gellman Jun 2016

Aspirational Planning: A Statistical Model Of Hawthorne Bridge And Tilikum Crossing Bicycle Ride Counts, Robert Mccullough, Ramon Cabauatan, Jacob Gellman

Hatfield Graduate Journal of Public Affairs

Portland city planners have routinely planned for an increase in bicycle commutership and a decrease in automobile commutership. This paper discusses the latest data on Portland car and bicycle use. Portland and Multnomah County are observing an increase in single occupancy vehicle commuters, car ownership, and gasoline consumption. Bicycle use in Portland is found to have followed a logistic curve pattern since the early 1990s. The authors present an ordinary least squares model to explain bicycle ridership on the Hawthorne Bridge and the recently constructed Tilikum Crossing. When controlling for other factors such as weather and daylight, the Tilikum Crossing …


Disseminating The Sustainable City Year Program (Scyp) Education Model, Nico Larco, Marc Schlossberg Apr 2016

Disseminating The Sustainable City Year Program (Scyp) Education Model, Nico Larco, Marc Schlossberg

TREC Final Reports

The University of Oregon has developed a catalytic learning model that simultaneously meets the needs of both the next generation’s transportation workforce and cities looking for innovative and catalytic ways to advance a new era of transportation goals. Named the Sustainable City Year Program (SCYP), the model links local community priorities (as expressed through local plans and city council goals) with courses from a range of disciplines at a nearby university. The UO program engages 500+ multidisciplinary students annually in providing 60,000+ hours of work to city-identified projects using the existing administrative systems of both universities and local communities.

This …


Growing Stem Education On The Playground: A Case Study Of The Factors That Influence Teachers’ Use Of School Gardens, Megan Poole Mar 2016

Growing Stem Education On The Playground: A Case Study Of The Factors That Influence Teachers’ Use Of School Gardens, Megan Poole

Dissertations and Theses

School gardens can have a profound, positive influence on a student's academic achievement, social skills, and attitudinal orientation. Despite these clear benefits, the use of school gardens as an instructional medium is not as prevalent as would be expected. There are several types of obstacles that can prevent teachers from using school gardens, including facets of time, support, and knowledge-based challenges. This multiple case study employs a mixed methods design to uncover factors that influence primary school teachers' decisions to utilize a school garden in their STEM curriculum. The goals of this study were to determine the types of benefits …


Learning Through Nature: A Study Of A Next Generation Science Standards Based Teacher Workshop That Blends Outdoor Learning Experiences With Formal Science, Ashley Fanning Mar 2016

Learning Through Nature: A Study Of A Next Generation Science Standards Based Teacher Workshop That Blends Outdoor Learning Experiences With Formal Science, Ashley Fanning

Dissertations and Theses

Many teachers lack the confidence and knowledge to transition their classroom science lessons to an outdoor setting. Very few teacher professional development (PD) programs focus on improving teachers' self-efficacy and pedagogical content knowledge (PCK) that is needed to enhance their science curriculum with outdoor lessons. This study examined an exception: The Connect2Science workshops, which provided elementary teachers the opportunity to experience nature-based science lessons. My research question for this study is: In what ways does a professional development workshop focused around the Next Generation Science Standards influence teachers': a) self-efficacy in teaching science outdoors and b) science pedagogical content knowledge? …


Faculty Senate Monthly Packet March 2016, Portland State University Faculty Senate Mar 2016

Faculty Senate Monthly Packet March 2016, Portland State University Faculty Senate

Faculty Senate Monthly Packets

The March 2016 Monthly packet includes the February agenda and appendices and the Faculty Senate minutes and attachments from the meeting held February 2016.


Ecosystem Services In Managing Residential Landscapes: Priorities, Value Dimensions, And Cross-Regional Patterns, Kelli L. Larson, Jennifer L. Morse, Peter M. Groffman, Neil D. Bettez, Tara Trammell Mar 2016

Ecosystem Services In Managing Residential Landscapes: Priorities, Value Dimensions, And Cross-Regional Patterns, Kelli L. Larson, Jennifer L. Morse, Peter M. Groffman, Neil D. Bettez, Tara Trammell

Environmental Science and Management Faculty Publications and Presentations

Although ecosystem services have been intensively examined in certain domains (e.g., forests and wetlands), little research has assessed ecosystem services for the most dominant landscape type in urban ecosystems—namely, residential yards. In this paper, we report findings of a cross-site survey of homeowners in six U.S. cities to 1) examine how residents subjectively value various ecosystem services, 2) explore distinctive dimensions of those values, and 3) test the urban homogenization hypothesis. This hypothesis posits that urbanization leads to similarities in the social-ecological dynamics across cities in diverse biomes. By extension, the thesis suggests that residents’ ecosystem service priorities for residential …


Mechanisms Of Methane Transport Through Populus Trichocarpa, Ellynne Marie Kutschera, M. A. K. Khalil, Andrew Rice, Todd Rosenstiel Mar 2016

Mechanisms Of Methane Transport Through Populus Trichocarpa, Ellynne Marie Kutschera, M. A. K. Khalil, Andrew Rice, Todd Rosenstiel

Physics Faculty Publications and Presentations

Although the dynamics of methane (CH4) emission from croplands and wetlands have been fairly well investigated, the contribution of trees to global CH4 emission and the mechanisms of tree transport are relatively unknown. CH4 emissions from the common wetland tree species Populus trichocarpa (black cottonwood) native to the Pacific Northwest were measured under hydroponic conditions in order to separate plant transport mechanisms from the influence of soil processes. Roots were exposed to CH4 enriched water and canopy emissions of CH4 were measured. The average flux for 34 trials (at temperatures ranging from 17 to 25 °C) was 2.8 ± 2.2 …


Urban Ecology & Conservation Symposium 2016: 14th Annual (Abstracts), Urban Ecosystem Research Consortium Of Portland/Vancouver Feb 2016

Urban Ecology & Conservation Symposium 2016: 14th Annual (Abstracts), Urban Ecosystem Research Consortium Of Portland/Vancouver

Urban Ecosystem Research Consortium of Portland/Vancouver

The UERC is a consortium of people from various universities and colleges, state and federal agencies, local governments, non-profit organizations and independent professionals interested in supporting urban ecosystem research and creating an information-sharing network of people that collect and use ecological data in the Portland/Vancouver area.

UERC Mission Statement:

To advance the state of the science of urban ecosystems and improve our understanding of them, with a focus on the Portland/Vancouver metropolitan region, by fostering communication and collaboration among researchers, managers and citizens at academic institutions, public agencies, local governments, non-profit organizations, and other interested groups.

The principal organizers span …


Creating Protected Areas On Public Lands: Is There Room For Additional Conservation?, Rodrigo A. Arriagada, Cristian M. Echeverria, Danisa E. Moya Feb 2016

Creating Protected Areas On Public Lands: Is There Room For Additional Conservation?, Rodrigo A. Arriagada, Cristian M. Echeverria, Danisa E. Moya

Forest Collaborative Research

Most evaluations of the effectiveness of PAs have relied on indirect estimates based on comparisons between protected and unprotected areas. Such methods can be biased when protection is not randomly assigned. We add to the growing literature on the impact of PAs by answering the following research questions: What is the impact of Chilean PAs on deforestation which occurred between 1986 and 2011? How do estimates of the impact of PAs vary when using only public land as control units? We show that the characteristics of the areas in which protected and unprotected lands are located differ significantly. To satisfactorily …


A Study On The Current State Of Contaminants Of Concern Research, With A Focus On Biosolids And Regulations, Maren Mariah Fulton Jan 2016

A Study On The Current State Of Contaminants Of Concern Research, With A Focus On Biosolids And Regulations, Maren Mariah Fulton

Civil and Environmental Engineering Master's Project Reports

Wastewater treatment plants are a major source of contaminants of emerging concern, as these facilities are the main receptors of these products via household, commercial, and industrial drains, and transport via stormwater runoff. Biosolids are composed of numerous constituents, with a number of environmentally persistent and potentially toxic contaminants of emerging concern identified as present in large concentrations. Research is needed to understand the transport and fate mechanisms of these compounds in biosolids. Additionally, this research is needed to determine a new priority framework to regulate CECs, both on the national level and regional levels. Wastewater treatment plant influent and …


Curriculum Change 2016-2017, Portland State University Jan 2016

Curriculum Change 2016-2017, Portland State University

Bulletin & Curriculum Change Documents

No abstract provided.


Climate And Bark Beetle Effects On Forest Productivity — Linking Dendroecology With Forest Landscape Modeling, Alec M. Kretchun, E. Louise Loudermilk, Robert M. Scheller, Matthew Hurteau, Soumaya Belmecher Jan 2016

Climate And Bark Beetle Effects On Forest Productivity — Linking Dendroecology With Forest Landscape Modeling, Alec M. Kretchun, E. Louise Loudermilk, Robert M. Scheller, Matthew Hurteau, Soumaya Belmecher

Environmental Science and Management Faculty Publications and Presentations

In forested systems throughout the world, climate influences tree growth and aboveground net primary productivity (ANPP). The effects of extreme climate events (i.e., drought) on ANPP can be compounded by biotic factors (e.g., insect outbreaks). Understanding the contribution of each of these influences on growth requires information at multiple spatial scales and is essential for understanding regional forest response to changing climate. The mixed conifer forests of the Lake Tahoe Basin, California and Nevada, provide an opportunity to analyze biotic and abiotic influences on ANPP. Our objective was to evaluate the influence of moisture stress (climatic water deficit, CWD) and …


Adverse Effects Of Mercury And Some Management Options To Reduce Dental Amalgam Waste, Marta Szabatin Jan 2016

Adverse Effects Of Mercury And Some Management Options To Reduce Dental Amalgam Waste, Marta Szabatin

University Honors Theses

Mercury is a persistent, toxic pollutant and at elevated levels can cause serious environmental harm to aquatic life, wildlife, and humans. Mercury from anthropogenic sources continues to be a significant risk to human health causing regulatory agencies to address this issue. The purpose of this study is to review the sources, forms and adverse effects of mercury, and identify the tools regulating mercury-containing dental waste management, and the advantages and disadvantages of various management practices that help to minimize mercury releases into municipal sewage system and into waterbodies. Dental facilities are significant mercury dischargers to wastewater treatment facilities and dental …


Following The Flat Hat: What Leads People To National Park Service Interpretive Careers?, Avarie Fitzgerald Jan 2016

Following The Flat Hat: What Leads People To National Park Service Interpretive Careers?, Avarie Fitzgerald

University Honors Theses

National Park Service interpreters around the United States are dedicated to connecting people to their parks and historical sites. While these interpretive rangers have an important mission of preserving the landscape and stories of our nation’s most treasured places, a gap in the research of significant life experiences and environmental education professions exists in understanding the motivations behind following a career in the park service. Through semi-structured phenomenological interviews, the significant life experiences of interpretive park rangers were investigated as to their degree of influence on their choice of career. The findings indicate that quality time spent outdoors, family involvement, …