Physical Sciences and Mathematics Commons^™

Archetypes Of Community Wildfire Exposure From National Forests Of The Western Us, Cody Evers, Alan A. Ager, Max Nielsen-Pincus, Palaiologos Palaiologou, Ken Bunzel

Environmental Science and Management Faculty Publications and Presentations

Risk management typologies and their resulting archetypes can structure the many social and biophysical drivers of community wildfire risk into a set number of strategies to build community resilience. Existing typologies omit key factors that determine the scale and mechanism by which exposure from large wildfires occur. These factors are particularly important for land managing agencies like the US Forest Service, which must weigh community wildfire exposure against other management priorities. We analyze community wildfire exposure from national forests by associating conditions that affect exposure in the areas where wildfires ignite to conditions where exposure likely occurs. Linking source and …

Patterns And Drivers Of Recent Disturbances Across The Temperate Forest Biome, Andreas Sommerfeld, Cornelius Senf, Brian Buma, Anthony W. D'Amato, Tiphaine Despres, Ignacio Díaz-Hormazábal, Shawn Fraver, Lee E. Frelich, Alvaro G. Gutiérrez, Sarah J. Hart, Brian J. Harvey, Hong S. He, Tomáš Hlásny, Andrés Holz, Multiple Additional Authors

Geography Faculty Publications and Presentations

Increasing evidence indicates that forest disturbances are changing in response to global change, yet local variability in disturbance remains high. We quantified this considerable variability and analyzed whether recent disturbance episodes around the globe were consistently driven by climate, and if human influence modulates patterns of forest disturbance. We combined remote sensing data on recent (2001–2014) disturbances with in-depth local information for 50 protected landscapes and their surroundings across the temperate biome. Disturbance patterns are highly variable, and shaped by variation in disturbance agents and traits of prevailing tree species. However, high disturbance activity is consistently linked to warmer and …

Sources Of Contaminated Flood Sediments In A Rural–Urban Catchment: Johnson Creek, Oregon, Heejun Chang, Deonie Allen, Jennifer L. Morse, Janardan Mainali

Geography Faculty Publications and Presentations

This study investigated the delivery of contaminated sediments to the channel network by urban drainage systems in Johnson Creek in Oregon, USA. Concentrations of five heavy metal concentrations measured in 136 samples collected from 37 stormwater outfalls and 99 bed sampling points were analysed. While concentrations of zinc, cadmium and lead increased with distance downstream in Johnson Creek, this was not the case for chromium and copper. Zinc, copper, and cadmium concentrations in outfalls were significantly higher than those in the stream bed, indicating that stormwater runoff is responsible for delivering contaminated sediments to Johnson Creek. Zinc concentrations in outfalls …

Ecosystem Services And U.S. Stormwater Planning: An Approach For Improving Urban Stormwater Decisions, Todd K. Bendor, Vivek Shandas, Brian Miles, Kenneth Belt, Lydia Olander

Urban Studies and Planning Faculty Publications and Presentations

Green stormwater infrastructure (GI) is gaining traction as a viable complement to traditional “gray” infrastructure in cities across the United States. As cities struggle with decisions to replace deteriorating stormwater infrastructure in the face of looming issues such as population growth and climate change, GI may offer a costeffective, efficient, and sustainable approach. However, decision makers confront challenges when integrating GI within city plans, including uncertainties around GI capacity and maintenance, resistance to collaboration across city governance, increasingly inflexible financing, accounting practices that do not incorporate the multiple values of GI, and difficulties in incorporating ecological infrastructure into stormwater management. …

Removal Efficiencies, Uptake Mechanisms And Competitive Effects Of Copper And Zinc In Various Stormwater Filter Media, Emily Heleva-Ponaski

Dissertations and Theses

Polluted stormwater, if not treated, can compromise water quality throughout our hydrologic cycle, adversely affecting aquatic ecosystems. Common stormwater pollutants, copper and zinc, have been identified as primary toxicants in multiple freshwater and marine environments. For small-scale generators, stormwater management can be cumbersome and implementation of common BMPs impractical thus catch basins are popular though not the most environmentally conscious and sustainable option. This study aims to characterize the potential of a mobile media filter operation for the treatment and on-site recycling of catch basin stormwater. The removal capacities of various commercially available filter media (e.g. a common perlite; Earthlite™, …

Ecology And Population Dynamics Of Salmonids In The Columbia River: Response Of Fishes To Anthropogenic Change In A Large Riverscape, Timothy Sean Elder

Dissertations and Theses

Freshwater ecosystems and the species that reside therein are disproportionately imperiled compared to terrestrial systems. Over the past 150 years, the Columbia River basin in the western United States has gone from one of the most productive and abundant salmon watersheds in the world, to having just a small fraction of its former salmon abundance. The cause of declines in salmon productivity and abundance are related to overlapping and confounding stressors including changes in large-scale climatic patterns and anthropogenic alterations within and adjacent to the Columbia River. Four main anthropogenic stressors have been identified as the leading causes of salmonid …

Are Government Incentives Effective For Avoided Deforestation In The Tropical Andean Forest?, Pablo Cuenca, Juan Robalino, Rodrigo A. Arriagada, Cristian M. Echeverria

Forest Collaborative Research

In order to ensure the provision of goods and services from forests, many governments have promoted less-traditional conservation initiatives such as programs of payments for ecosystem services called, more broadly, direct payments for conservation. The Socio Bosque Program (SBP) is a governmental program in Ecuador that directly provides economic incentives to rural families and local and indigenous communities who have voluntarily agreed to comply with some conservation activities. An impact evaluation method (matching) was used to assess the impact of the SBP between 2008 and 2014. This study revealed that on average, the SBP reduced deforestation by 1.5% in those …

Public Perceptions Of Mountain Lake Fisheries Management In National Parks, Ariana M. Chiapella, Max Nielsen-Pincus, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

The legacy of fish stocking in mountain lake ecosystems has left behind a challenge for land managers around the globe. In the US and Canada, historically fishless mountain lakes have been stocked with trout for over a century. These non-native trout have cascading ecosystem effects, and can accumulate atmospherically deposited contaminants. While the negative impacts of stocking in these ecosystems have become increasingly apparent, wilderness fishing has garnered cultural value in the angling community. As a result, public lands managers are left with conflicting priorities. National park managers across the western US are actively trying to reconcile the cultural and …

Ideals, Big Varieties, And Dynamic Networks, Ian H. Dinwoodie

Mathematics and Statistics Faculty Publications and Presentations

The advantage of using algebraic geometry over enumeration for describing sets related to attractors in large dynamic networks from biology is advocated. Examples illustrate the gains.

Gps Constraints On Deformation In Northern Central America From 1999 To 2017, Part 1 – Time-Dependent Modelling Of Large Regional Earthquakes And Their Post-Seismic Effects, A. Ellis, Charles Demets, P. Briole, Beatriz Cosenza, Omar Flores, Shannon Graham, Marco Guzmán-Speziale, Douglas Hernandez, Vladimir Kostoglodov, Peter Lafemina, Neal Lord, Cécile Lasserre, Hélène Lyon-Caen, Manuel Rodriguez Maradiaga, Robert Mccaffrey, Enrique Molina, Jeffrey Rivera, Robert Rogers, Alejandra Staller

Geology Faculty Publications and Presentations

We use continuous and campaign measurements from 215 GPS sites in northern Central America and southern Mexico to estimate coseismic and afterslip solutions for the 2009 Mw = 7.3 Swan Islands fault strike-slip earthquake and the 2012 Mw = 7.3 El Salvador and Mw = 7.4 Guatemala thrust-faulting earthquakes on the Middle America trench. Our simultaneous, time-dependent inversion of more than 350 000 daily GPS site positions gives the first jointly consistent estimates of the coseismic slips for all three earthquakes, their combined time-dependent post-seismic effects and secular station velocities corrected for both the coseismic and post-seismic deformation. Our geodetic …

Decadal Topographic Change In The Mcmurdo Dry Valleys Of Antarctica: Thermokarst Subsidence, Glacier Thinning, And Transfer Of Water Storage From The Cryosphere To The Hydrosphere, J. S. Levy, Andrew G. Fountain, M. K. Obryk, J. Telling, Craig Glennie, M. Gooseff, David J. Van Horn

Geology Faculty Publications and Presentations

Recent local-scale observations of glaciers, streams, and soil surfaces in the McMurdo Dry Valleys of Antarctica (MDV) have documented evidence for rapid ice loss, glacial thinning, and ground surface subsidence associated with melting of ground ice. To evaluate the extent,magnitude, and location of decadal-scale landscape change in the MDV, we collected airborne lidar elevation data in 2014–2015 and compared these data to a 2001–2002 airborne lidar campaign. This regional assessment of elevation change spans the recent acceleration of warming and melting observed by long-term meteorological and ecosystem response experiments, allowing us to assess the response of MDV surfaces to warming …

Gps Constraints On Deformation In Northern Central America From 1999 To 2017, Part 1 – Time-Dependent Modelling Of Large Regional Earthquakes And Their Post-Seismic Effects, A. Ellis, Charles Demets, P. Briole, Beatriz Cosenza, Omar Flores, Shannon E. Graham, Robert Mccaffrey, Multiple Additional Authors

Geology Faculty Publications and Presentations

We use continuous and campaign measurements from 215 GPS sites in northern Central America and southern Mexico to estimate coseismic and afterslip solutions for the 2009 M_w = 7.3 Swan Islands fault strike-slip earthquake and the 2012 M_w = 7.3 El Salvador and M_w = 7.4 Guatemala thrust-faulting earthquakes on the Middle America trench. Our simultaneous, time-dependent inversion of more than 350 000 daily GPS site positions gives the first jointly consistent estimates of the coseismic slips for all three earthquakes, their combined time-dependent post-seismic effects and secular station velocities corrected for both the coseismic and post-seismic …

Using Strong Laser Fields To Produce Antihydrogen Ions, Christopher Michael Keating

Dissertations and Theses

We provide estimates of both cross section and rate for the stimulated attachment of a second positron into the (1s^{2 1}S^e) state of the H+ ion using Ohmura and Ohmura's (1960 Phys. Rev. 118 154) effective range theory, Reiss's strong field approximation (1980 Phys. Rev. A 22, 1786), and the principle of detailed balancing. Our motivation for producing H+ ion include its potential to be used as an intermediate state in bringing antihydrogen to ultra-cold (sub-mK) temperatures required for a variety of studies, which include both spectroscopy and the probing of the gravitational interaction of …

Assessing Spatiotemporal Stream Temperature Trends And Drivers Through Integrated Longitudinal Thermal Profiling And Stationary Data Logger Methodology On The Upper Chehalis River, Wa, Whitney Vonada

Dissertations and Theses

This study encompasses 25 kilometers of the Chehalis River in Washington, USA that currently has sections under a Total Maximum Daily Load (TMDL) plan for stream temperature impairments that exceed 18°C, a regulatory standard set at the time of the listing to protect salmonid spawning, rearing, and migration. Using information integrated from stationary data loggers (n=22) that collected stream temperature information from August 4-September 10, 2017, and longitudinal thermal profiling performed on July 29-30, August 4-5, and September 9-10, 2017, this study aimed to quantify the spatial distribution of stream temperature, evaluate relative consistencies of the riverine thermal regime over …

Supercanonical Probability Distributions, John D. Ramshaw

Physics Faculty Publications and Presentations

The canonical probability distribution describes a system in thermal equilibrium with an infinite heat bath. When the bath is finite the distribution is modified. These modifications can be derived by truncating a Taylor-series expansion of the entropy of the heat bath, but their form depends on the expansion parameter chosen. We consider two such expansions, which yield supercanonical (i.e., higher-order canonical) distributions of exponential and power-law form. The latter is identical in form to the "Tsallis distribution," which is therefore a valid asymptotic approximation for an arbitrary finite heat bath, but bears no intrinsic relation to Tsallis entropy.

Removing Dams, Constructing Science: Watershed Restoration Through A Socio-Eco-Technical Systems Lens, Zbigniew Jakub Grabowski

Dissertations and Theses

Ecological conservation and restoration in the anthropocene must struggle with overlapping drivers of biodiversity and cultural loss; ruptures of the ecological environment mirror ruptures of human relationships with nature. And yet technology cannot remove humans from nature; technological and infrastructural reconfigurations of nature create new vulnerabilities and risks for humans and ecosystems alike. How can conservation and restoration science productively grapple with complex infrastructure systems and decision-making processes as biophysical and social drivers of ecosystem change?

Using dam removals in the USA and in the Mid Columbia River region of the Pacific Northwest, this dissertation develops a conceptual framework for …

Thiophene-Based Molecular Sensors Towards The Selective Detection Of Mercury(Ii) And Other Metals, Austin Kazuo Shigemoto

Dissertations and Theses

This work describes several thiophene-based molecular sensors and various modifications aimed to improve and understand the photophysical and supramolecular properties, such as the association constant (K_a) and selectivity, towards the development of a selective mercury(II) sensor. From the first generation of sensors containing pyridine and thiophene groups, it was determined that thiophene can offer good selectivity for mercury(II) against other transition metal ions, and provide a ratiometric absorption and fluorescent response. The projects following this focused on improving the K_a of the first generation of sensors through several different strategies. Substitution of thiophene for dibenzothiophene was …

Twelve Questions For The Participatory Modeling Community, Rebecca Jordan, Steven Gray, Moira Zellner, Pierre D. Glynn, Alexey Voinov, Beatrice Hedelin, Eleanor J. Sterling, Kirsten Leong, Laura Schmitt Olabisi, Klaus Hubacek, Pierre Bommel, Todd K. Bendor, Antoine J. Jetter, Bethany Laursen, Alison Singer, Philippe J. Giabbanelli, Nagesh Kolagani, Laura Basco Carrera, Karen Jenni, Christina Prell, National Socio-Environmental Synthesis Center Participatory Modeling Pursuit Working Group

Engineering and Technology Management Faculty Publications and Presentations

Participatory modeling engages the implicit and explicit knowledge of stakeholders to create formalized and shared representations of reality and has evolved into a field of study as well as a practice. Participatory modeling researchers and practitioners who focus specifically on environmental resources met at the National Socio-Environmental Synthesis Center (SESYNC) in Annapolis, Maryland, over the course of 2 years to discuss the state of the field and future directions for participatory modeling. What follows is a description of 12 overarching groups of questions that could guide future inquiry.

Rock Glaciers Of The Contiguous United States: Spatial Distribution, Cryospheric Context, And Riparian Vegetation, Gunnar Forrest Johnson

Dissertations and Theses

Continental-scale inventories of glaciers are available, but no analogous rock glacier inventories exist. We present the Portland State University Rock Glacier Inventory (n = 10,343) for the contiguous United States, then compare it to an existing inventory of contiguous United States glaciers (n = 853), identifying geographic and climatic factors affecting the spatial distributions observed. At least one rock glacier is identified in each of the 11 westernmost states, but nearly 90% are found in just five; Colorado (n = 3889), Idaho (n = 1723), Montana (n = 1780), Utah (n = 834), and Wyoming (n = 849). Glaciers are …

Using Wetlands To Prevent The Surface Accumulation Of Aphanizomenon Flos-Aquae From Upper Klamath Lake, Arick Christopher Rouhe

Dissertations and Theses

The ability to regulate buoyancy (sinking and floating) using cellular gas vesicles is a unique characteristic that allows many common bloom-forming cyanobacteria to accumulate at water surfaces and dominate systems. Typical control and management strategies include nutrient manipulation and phosphorus reduction, which are effective but do not reduce the advantage of buoyancy control. Since buoyancy control is based upon a mechanism that is driven by photosynthesis along with environmental conditions that trigger vesicle formation and ion exchange, buoyancy regulation can be influenced by manipulating extracellular conditions. In this study I manipulated extracellular conditions using wetland water and additions of potassium, …

Psu University Services Building Leed Eb Materials Audit Report, Christa Mcdermott, Emily Murkland, Bryan Nguyen, Tay Stone, Rushada Wimer

Campus Sustainability Office Publications, Reports and Presentations

This report provides Portland State University’s (PSU) Campus Sustainability Office (CSO), with an objective third party LEED O+M Materials Assessment of PSU’s University Services Building (USB). The data collected for this audit provides CSO with insight into the building’s current waste composition and diversion rate. Additionally, it identifies opportunities to reduce the amount of recoverable materials ending up in the landfill stream. Community Environmental Services (CES) conducted material audits for 100% of USB’s landfill-bound, commingled recycling, and compost streams during a 24-hour period. While, audited construction and demolition (C&D) materials were generated over the course of a week.

Entanglement Entropy, Dualities, And Deconfinement In Gauge Theories, Mohamed M. Anber, Benjamin J. Kolligs

Portland Institute for Computational Science Publications

Computing the entanglement entropy in confining gauge theories is often accompanied by puzzles and ambiguities. In this work we show that compactifying the theory on a small circle S ^1/L evades these difficulties. In particular, we study Yang-Mills theory on R³×S ^1/L with double-trace deformations or adjoint fermions and hold it at temperatures near the deconfinement transition. This theory is dual to a multi-component (electric-magnetic) Coulomb gas that can be mapped either to an XY-spin model with Z_p symmetry-preserving perturbations or dual Sine-Gordon model. The entanglement entropy of the dual SineGordon model exhibits an extremum at the …

Tools And Methods In Participatory Modeling: Selecting The Right Tool For The Job, Alexey Voinov, Karen Jenni, Steven Gray, Nagesh Kolagani, Pierre D. Glynn, Pierre Bommel, Christina Prell, Moira Zellner, Michael Paolisso, Rebecca Jordan, Eleanor J. Sterling, Laura Schmitt Olabisi, Philippe J. Giabbanelli, Zhanli Sun, Christophe Le Page, Sondoss Elsawah, Todd K. Bendor, Klaus Hubacek, Bethany Laursen, Antoine J. Jetter, Laura Basco-Carrera, Alison Singer, Laura Young, Jessica Brunacini, Alex Smajgl

Engineering and Technology Management Faculty Publications and Presentations

Various tools and methods are used in participatory modelling, at different stages of the process and for different purposes. The diversity of tools and methods can create challenges for stakeholders and modelers when selecting the ones most appropriate for their projects. We offer a systematic overview, assessment, and categorization of methods to assist modelers and stakeholders with their choices and decisions. Most available literature provides little justification or information on the reasons for the use of particular methods or tools in a given study. In most of the cases, it seems that the prior experience and skills of the modelers …

Structural Instability And Dynamic Emission Fluctuations In Zinc Oxide Random Lasers, Zachariah Peterson, Robert Campbell Word, Rolf Könenkamp

Physics Faculty Publications and Presentations

We report experimental results on the structural stability of optically pumped zinc oxide random lasers. We find that the lasing threshold is not entirely stable and depends on the accumulated light exposure received in pulsed optical pumping. We show that exposure levels below ∼1.5 kJ/cm2 improve the lasing efficiency and lower the lasing threshold. Beyond that value, however, lasing efficiency and threshold begin to degrade. Electron microscopy shows that the degradation is accompanied by morphological changes characteristic of melting. These changes become visible at an exposure of ∼0.7 kJ/cm2. We suggest that the melting is initially localized within nanometer areas …

Special Issue On Climate Change And Land Conservation And Restoration: Advances In Economics Methods And Policies For Adaptation And Mitigation, Sarah Cline, Sahan T.M. Dissanayake

Economics Faculty Publications and Presentations

Climate change will likely impact the ecosystem services and biodiversity generated from conserved land. Land conservation can also play a significant role in achieving cost-effective mitigation of greenhouse gas emissions. In this special issue we feature seven papers from the 2017 NAREA Workshop, “Climate Change and Land Conservation and Restoration: Advances in Economics Methods and Policies for Adaptation and Mitigation.” The articles include papers furthering the methodological frontier; portfolio optimization, dynamic rangeland stocking, and global timber harvest models, and those highlighting innovative applications; climate smart agricultural practices in Nigeria and Vietnam, welfare impacts on birding, and carbon and albedo pricing.

Connection And Curvature In Crystals With Non-Constant Dislocation Density, Marek Z. Elźanowski, Gareth P. Parry

Mathematics and Statistics Faculty Publications and Presentations

Given a smooth defective solid crystalline structure defined by linearly independent ‘lattice’ vector fields, the Burgers vector construction characterizes some aspect of the ‘defectiveness’ of the crystal by virtue of its interpretation in terms of the closure failure of appropriately defined paths in the material and this construction partly determines the distribution of dislocations in the crystal. In the case that the topology of the body manifold M is trivial (e.g., a smooth crystal defined on an open set in R2), it would seem at first glance that there is no corresponding construction that leads to the notion of a …

Electron Backscatter Diffraction (Ebsd) Study Of Seven Heavily Metamorphosed Chondrites: Deformation Systematics And Variations In Pre-Shock Temperature And Post-Shock Annealing, Alexander M. Ruzicka, Richard C. Hugo

Geology Faculty Publications and Presentations

We used electron backscatter diffraction (EBSD) methods to study the crystallography of olivine and other minerals in seven heavily metamorphosed (petrographic type 6 or 6/7) but variably shocked ordinary chondrites from the H (Kernouvé, Portales Valley), L (Leedey, Bruderheim, Morrow County, Park) and LL (Miller Range (MIL) 99301) groups. MIL 99301 contains a large clast that was analyzed separately. Mesoscale (EBSD) data support and extend inferences based on microscale (TEM) observations and provide good evidence that chondrites were shock-deformed at different temperatures and were variably annealed (sintered) after deformation. Various EBSD deformation intensity metrics adequately and quantitatively represent olivine deformation …

Dynamics Of Magma Recharge And Mixing At Mount Hood Volcano, Oregon -- Insights From Enclave-Bearing Lavas, Molly Kathryn Ellowitz

Dissertations and Theses

Magma recharge events and subsequent mixing processes are understood to precede volcanic eruptions. Textural evidence of intrusion of hot, mafic magma into a cooler, rheologically locked silicic magma is commonplace. Solidified "blobs" of injected magma, called enclaves, are evidence of magma mixing, but the petrological and mechanical conditions during their formation are debated. Mount Hood, Oregon consistently erupts andesite bearing compositionally similar enclaves. These enclaves are evidence of mingling and mixing of two magmas. However, due to the compositional similarity between enclave and host lava (e.g. ~1-5 wt.% difference in SiO₂), it is unclear whether the preserved enclaves …

Effectiveness Of Pollinator Enhancements In Portland Community Orchards, Jess Alan Tyler

Dissertations and Theses

In urban areas, residential and community gardens are potential floral resources for pollinators. Pollinator "friendly" gardens are a popular way to support this ecosystem service, but the pollinator plant list recommendations lack empirical evidence to show which plants are most attractive to potential pollinators. This project used a community science survey based on a morpho-species protocol to monitor five community orchards in Portland, Oregon during six months of the growing season in 2017. Overall, orchards with higher floral species richness supported higher richness and abundance of pollinators, but the pollinator communities were not significantly different among the orchard sites. Orchard …

A New Functional-Logic Compiler For Curry: Sprite, Sergio Antoy, Andy Jost

Computer Science Faculty Publications and Presentations

We introduce a new native code compiler for Curry codenamed Sprite. Sprite is based on the Fair Scheme, a compilation strategy that provides instructions for transforming declarative, non-deterministic programs of a certain class into imperative, deterministic code. We outline salient features of Sprite, discuss its implementation of Curry programs, and present benchmarking results. Sprite is the first-to-date operationally complete implementation of Curry. Preliminary results show that ensuring this property does not incur a significant penalty.