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Environmental Sciences

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Portland State University

2015

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Engineering A Healthier Watershed: Middle School Students Use Engineering Design To Lessen The Impact Of Their Campus' Impervious Surfaces On Their Local Watershed, Elizabeth Claire Gardner Dec 2015

Engineering A Healthier Watershed: Middle School Students Use Engineering Design To Lessen The Impact Of Their Campus' Impervious Surfaces On Their Local Watershed, Elizabeth Claire Gardner

Dissertations and Theses

It is important that students understand not only how their local watershed functions, but also how it is being impacted by impervious surfaces. Additionally, students need experience exploring the scientific and engineering practices that are necessary for a strong STEM background. With this knowledge students can be empowered to tackle this real and local problem using engineering design, a powerful practice gaining momentum and clarity through its prominence in the recent Framework for K-12 Science Education. Twenty classes of suburban sixth-graders participated in a new five-week Watershed Engineering Design Unit taught by their regular science teachers. Students engaged in scientific …


Next-Generation Scientists Get A Taste Of Their Future Careers, Patrick M. Edwards, Linda A. George, Matthew Mctammany Dec 2015

Next-Generation Scientists Get A Taste Of Their Future Careers, Patrick M. Edwards, Linda A. George, Matthew Mctammany

Environmental Science and Management Faculty Publications and Presentations

Article provides an overview of the middle and high school poster session that took place during the 2014 Joint Aquatic Sciences Meeting (JASM) in Portland, Oregon. The poster session provided the students with opportunity to participate in the research process and prepare their posters.


Integrating Freight Into Livable Communities, Kristine M. Williams, Alexandria Carroll Dec 2015

Integrating Freight Into Livable Communities, Kristine M. Williams, Alexandria Carroll

TREC Final Reports

Where livability is a goal of the planning process, freight runs the risk of not being considered except as an afterthought or as something to be excluded. Yet, freight is an integral part of local economic development. Because economic prosperity is a key characteristic of livable communities, freight must be incorporated into the planning process. This study explores the relationship between freight and livability through a comprehensive literature review and case study research. The final report includes a menu of strategies and case study perspectives that highlight the importance of transportation and land use integration, interagency coordination, and context-sensitivity in …


Stressors And Strategies For Managing Urban Water Scarcity: Perspectives From The Field, Vivek Shandas, Rosa Lehman, Kelli L. Larson, Jeremy Bunn, Heejun Chang Dec 2015

Stressors And Strategies For Managing Urban Water Scarcity: Perspectives From The Field, Vivek Shandas, Rosa Lehman, Kelli L. Larson, Jeremy Bunn, Heejun Chang

Urban Studies and Planning Faculty Publications and Presentations

Largely because water resource planning in the U.S. has been separated from land-use planning, opportunities for explicitly linking planning policies to water availability remain unexamined. The pressing need for better coordination between land-use planning and water management is amplified by changes in the global climate, which will place even greater importance on managing water supplies and demands than in the past. By surveying land and water managers in two urbanizing regions of the western United States—Portland, Oregon and Phoenix Arizona—we assessed the extent to which their perspectives regarding municipal water resource management align or differ. We specifically focus on characterizing …


The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2015, David J. Lauten, Kathleen A. Castelein, J. Daniel Farrar, Adam A. Kotaich, Eleanor P. Gaines Dec 2015

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2015, David J. Lauten, Kathleen A. Castelein, J. Daniel Farrar, Adam A. Kotaich, Eleanor P. Gaines

Institute for Natural Resources Publications

We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast from 3 April – 11 September 2015. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North and South Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River HRA and adjacent lands, and Floras Lake. Our objectives in 2015 were to: 1) estimate the size of the adult Snowy Plover population along the Oregon coast, 2) locate plover nests, 3) determine …


Evaluation Of Large‑Scale Meteorological Patterns Associated With Temperature Extremes In The Narccap Regional Climate Model Simulations, Paul C. Loikith, Duane E. Waliser, Huikyo Lee, J. David Neelin, Benjamin Lintner, Seth Mcginnis, Linda Mears, Jinwon Kim Dec 2015

Evaluation Of Large‑Scale Meteorological Patterns Associated With Temperature Extremes In The Narccap Regional Climate Model Simulations, Paul C. Loikith, Duane E. Waliser, Huikyo Lee, J. David Neelin, Benjamin Lintner, Seth Mcginnis, Linda Mears, Jinwon Kim

Geography Faculty Publications and Presentations

Large-scale meteorological patterns (LSMPs) associated with temperature extremes are evaluated in a suite of regional climate model (RCM) simulations contributing to the North American Regional Climate Change Assessment Program. LSMPs are characterized through composites of surface air temperature, sea level pressure, and 500 hPa geopotential height anomalies concurrent with extreme temperature days. Six of the seventeen RCM simulations are driven by boundary conditions from reanalysis while the other eleven are driven by one of four global climate models (GCMs). Four illustrative case studies are analyzed in detail. Model fidelity in LSMP spatial representation is high for cold winter extremes near …


Utilizing Humidity And Temperature Data To Advance Monitoring And Prediction Of Meteorological Drought, Ali Behrangi, Paul C. Loikith, Eric J. Fetzer, Hai M. Nguyen, Stephanie L. Granger Nov 2015

Utilizing Humidity And Temperature Data To Advance Monitoring And Prediction Of Meteorological Drought, Ali Behrangi, Paul C. Loikith, Eric J. Fetzer, Hai M. Nguyen, Stephanie L. Granger

Geography Faculty Publications and Presentations

The fraction of land area over the Continental United States experiencing extreme hot and dry conditions has been increasing over the past several decades, consistent with expectation from anthropogenic climate change. A clear concurrent change in precipitation, however, has not been confirmed. Vapor pressure deficit (VPD), combining temperature and humidity, is utilized here as an indicator of the background atmospheric conditions associated with meteorological drought. Furthermore, atmospheric conditions associated with warm season drought events are assessed by partitioning associated VPD anomalies into the temperature and humidity components. This approach suggests that the concurrence of anomalously high temperature and low humidity …


Dreissenid Mussel Research Priorities Workshop, Mark D. Sytsma, Stephen Phillips, Timothy D. Counihan Nov 2015

Dreissenid Mussel Research Priorities Workshop, Mark D. Sytsma, Stephen Phillips, Timothy D. Counihan

Center for Lakes and Reservoirs Publications and Presentations

Currently, dreissenid mussels have yet to be detected in the northwestern part of the United States and western Canada. Infestation of one of the jurisdictions within the mussel-free Pacific Northwest would likely have significant economic, soci­etal and environmental implications for the entire region. Understanding the biology and environmental tolerances of dreissenid mussels, and effectiveness of various man­agement strategies, is key to prevention.

On November 4-5, 2015, the Aquatic Bioinvasion Research and Policy Institute and the Center for Lakes and Reservoirs at Portland State University, the US Geological Survey, and the Pacific States Marine Fisheries Commission, convened a Dreissenid Mussel Research …


Gc/Ms Analysis Of Some Extractives From Eichhornia Crassipes, Héctor A. Fileto-Pérez, O. Miriam Rutiaga-Quiñones, Mark D. Sytsma, Isabelle M. Lorne, Wentai Luo, James F. Pankow, José G. Rutiaga-Quiñones Nov 2015

Gc/Ms Analysis Of Some Extractives From Eichhornia Crassipes, Héctor A. Fileto-Pérez, O. Miriam Rutiaga-Quiñones, Mark D. Sytsma, Isabelle M. Lorne, Wentai Luo, James F. Pankow, José G. Rutiaga-Quiñones

Environmental Science and Management Faculty Publications and Presentations

Eichhornia crassipes (water hyacinth) is an invasive weed that causes serious issues for rivers, lakes, and other reservoirs around the world, although it can be an excellent source for bioactive compounds such as phytosterols and some steroids found in many plants. In this study, water hyacinth samples from both Durango and Distrito Federal in Mexico were collected. Ascendant extracts (cyclohexane, hexane, acetone, and methanol) from their leaves, stems, and roots were analyzed. Using boron trifluoride (similar to 10% [similar to 1.3 M] in 1-butanol), all extracts were derivatized. Twenty-four derivatized samples were analyzed using a gas chromatography-mass spectrometry (GC/MS) method. …


Increased Taxonomic And Functional Similarity Does Not Increase The Trophic Similarity Of Communities, Thomas K. Pool, Julien Cucherousset, Stéphanie Boulêtreau, Sébastien Villéger, Angela L. Strecker, Gaël Grenouillet Nov 2015

Increased Taxonomic And Functional Similarity Does Not Increase The Trophic Similarity Of Communities, Thomas K. Pool, Julien Cucherousset, Stéphanie Boulêtreau, Sébastien Villéger, Angela L. Strecker, Gaël Grenouillet

Environmental Science and Management Faculty Publications and Presentations

Aim: Despite a long-standing research interest in the association between the biodiversity (i.e. taxonomic and functional composition) and trophic structure of communities, our understanding of the relationship remains limited. Community assembly theory predicts that niche partitioning will result in communities with a diverse array of functional traits, which in turn may facilitate a correspondingly diverse array of trophic interactions that define the trophic niche of those communities. The aim of our study is to test this prediction.

Methods: We built a database composed of functional traits and stable isotope values (δ13C and δ15N) for …


Convergence Of Microclimate In Residential Landscapes Across Diverse Cities In The United States, Sharon J. Hall, J Learned, Benjamin Ruddell, Kelli L. Larson, Jeannine Cavender-Bares, Neil D. Bettez, Peter M. Groffman, J. Morgan Grove, James B. Heffernan, Sarah E. Hobbie, Kristen Larson, Jennifer L. Morse, Christopher Neill, Kristen C. Nelson, Jarlath O'Neil-Dunne, Laura A. Ogden, Diane E. Pataki, William D. Pearse, Colin Polsky, Rinku Roy Chowdhury, Meredith K. Steele, Tara Trammell Oct 2015

Convergence Of Microclimate In Residential Landscapes Across Diverse Cities In The United States, Sharon J. Hall, J Learned, Benjamin Ruddell, Kelli L. Larson, Jeannine Cavender-Bares, Neil D. Bettez, Peter M. Groffman, J. Morgan Grove, James B. Heffernan, Sarah E. Hobbie, Kristen Larson, Jennifer L. Morse, Christopher Neill, Kristen C. Nelson, Jarlath O'Neil-Dunne, Laura A. Ogden, Diane E. Pataki, William D. Pearse, Colin Polsky, Rinku Roy Chowdhury, Meredith K. Steele, Tara Trammell

Environmental Science and Management Faculty Publications and Presentations

Context The urban heat island (UHI) is a welldocumented pattern of warming in cities relative to rural areas. Most UHI research utilizes remote sensing methods at large scales, or climate sensors in single cities surrounded by standardized land cover. Relatively few studies have explored continental-scale climatic patterns within common urban microenvironments such as residential landscapes that may affect human comfort.

Objectives We tested the urban homogenization hypothesis which states that structure and function in cities exhibit ecological ‘‘sameness’’ across diverse regions relative to the native ecosystems they replaced.

Methods We deployed portable micrometeorological sensors to compare air temperature and humidity …


Ozone Reaction With Interior Building Materials: Influence Of Diurnal Ozone Variation, Temperature And Humidity, Donghyun Rim, Elliott T. Gall, Randy L. Maddalena, William W. Nazaroff Oct 2015

Ozone Reaction With Interior Building Materials: Influence Of Diurnal Ozone Variation, Temperature And Humidity, Donghyun Rim, Elliott T. Gall, Randy L. Maddalena, William W. Nazaroff

Mechanical and Materials Engineering Faculty Publications and Presentations

Elevated tropospheric ozone concentrations are associated with increased morbidity and mortality. Indoor ozone chemistry affects human exposure to ozone and reaction products that also may adversely affect health and comfort. Reactive uptake of ozone has been characterized for many building materials; however, scant information is available on how diurnal variation of ambient ozone influences ozone reaction with indoor surfaces. The primary objective of this study is to investigate ozone-surface reactions in response to a diurnally varying ozone exposure for three common building materials: ceiling tile, painted drywall, and carpet tile. A secondary objective is to examine the effects of air …


Does Gender Matter? Human Elephant Conflict In Sri Lanka: A Gendered Analysis Of Human Elephant Conflict And Natural Resource Management In A Rural Sri Lankan Village, Katherine Eileen Griffin Sep 2015

Does Gender Matter? Human Elephant Conflict In Sri Lanka: A Gendered Analysis Of Human Elephant Conflict And Natural Resource Management In A Rural Sri Lankan Village, Katherine Eileen Griffin

Dissertations and Theses

This study is a gendered analysis of natural resource management at the local scale of a poor rural Sri Lankan village in a conservation buffer zone. This village experiences destruction of forests and human elephant conflict. The objective of this study is to gain an in-depth knowledge of residents' use and understandings of environmental resources, and to investigate if gender helps shape these factors. This study relies on a social sustainability conceptual framework. It tracks participation of local women and men in natural resource management, and in conservation within and outside of the Bibile community. Local nongovernmental organizations focus on …


Diurnal And Seasonal Variations Of No, No2 And Pm2.5 Mass As A Function Of Traffic Volumes Alongside An Urban Arterial, Christine M. Kendrick, Peter Koonce, Linda A. George Sep 2015

Diurnal And Seasonal Variations Of No, No2 And Pm2.5 Mass As A Function Of Traffic Volumes Alongside An Urban Arterial, Christine M. Kendrick, Peter Koonce, Linda A. George

Environmental Science and Management Faculty Publications and Presentations

Urban arterial corridors are landscapes that give rise to short and long-term exposures to transportation-related pollution. With high traffic volumes and a wide mix of road users, urban arterial environments are important targets for improved exposure assessment to traffic-related pollution. A common method to estimate exposure is to use traffic volumes as a proxy. The study presented here analyzes a unique yearlong dataset of simultaneous roadside air quality and traffic observations for a U.S. arterial to assess the reliability of using traffic volumes as a proxy for traffic-related exposure. Results show how the relationships of traffic volumes with NO and …


Climate-Suitable Planting As A Strategy For Maintaining Forest Productivity And Functional Diversity, Matthew Joshua Duveneck, Robert M. Scheller Sep 2015

Climate-Suitable Planting As A Strategy For Maintaining Forest Productivity And Functional Diversity, Matthew Joshua Duveneck, Robert M. Scheller

Environmental Science and Management Faculty Publications and Presentations

Within the time frame of the longevity of tree species, climate change will change faster than the ability of natural tree migration. Migration lags may result in reduced productivity and reduced diversity in forests under current management and climate change. We evaluated the efficacy of planting climate-suitable tree species (CSP), those tree species with current or historic distributions immediately south of a focal landscape, to maintain or increase aboveground biomass, productivity, and species and functional diversity. We modeled forest change with the LANDIS-II forest simulation model for 100 years (2000–2100) at a 2-ha cell resolution and five-year time steps within …


A Geospatial Tool For Wetland Prioritization At The Watershed Scale, Debra Sue Blackmore, Heejun Chang Sep 2015

A Geospatial Tool For Wetland Prioritization At The Watershed Scale, Debra Sue Blackmore, Heejun Chang

Institute for Natural Resources Publications

There is an increasing demand for assessing ecosystem functions for freshwater wetlands, especially when comparing or prioritizing among wetlands at the watershed scale. We estimated the relative potential of selected ecosystem functions for freshwater wetlands within a watershed using widely available geospatial data. We developed four functions to estimate 1) flood storage, 2) late season flow, 3) sediment retention and 4) temperature control in four pilot watersheds in Oregon (Tualatin, Coquille, Upper Grande Ronde and Sprague). These watersheds are geographically separated from each other representing diverse ecoregion environments. Spatial analysis and geographic information system (GIS) were designed for maximum re-use, …


Portland’S Food Economy: Trends And Contributions, Jamaal Green, Greg Schrock, Jenny H. Liu Aug 2015

Portland’S Food Economy: Trends And Contributions, Jamaal Green, Greg Schrock, Jenny H. Liu

Institute for Sustainable Solutions Publications and Presentations

The primary goal of this report is to document the scope, growth, and contribution of the food economy to the city of Portland and the region. Specifically, this report addresses the following research questions:

  • What is the "food economy," and how is it defined?
  • What is the size of Portland’s food economy, and how has it changed in recent years?
  • How is the food economy distributed spatially within the city and the region? How is this changing?
  • What kind of employment opportunities does Portland’s food economy offer? How do they compare to the broader economy?
  • Who works in Portland’s food …


Historical And Existing Vascular And Bryophyte Flora, Former Blue Heron Paper Mill, Willamette Falls, Oregon City, Oregon, John A. Christy, Philip Gaddis Aug 2015

Historical And Existing Vascular And Bryophyte Flora, Former Blue Heron Paper Mill, Willamette Falls, Oregon City, Oregon, John A. Christy, Philip Gaddis

Institute for Natural Resources Publications

Willamette Falls has long been a focus of botanical interest, but industrial development at the site has limited public access for over a century. The closure of the Blue Heron paper mill on the south bank of the river, and proposed redevelopment of the site, has given planners an opportunity to revisit this part of the falls and identify its current flora. As part of the preconstruction planning process for public access to the falls, Metro contracted John Christy to document the historical and existing vascular flora on the site, and Philip Gaddis joined us to document the bryophyte flora. …


Empirical Evidence For The Scale Dependence Of Biotic Interactions, Jonathan Belmaker, Phoebe Zarnetske, Sara Zonneveld, Sydne Record, Angela L. Strecker, Lydia Beaudrot Jul 2015

Empirical Evidence For The Scale Dependence Of Biotic Interactions, Jonathan Belmaker, Phoebe Zarnetske, Sara Zonneveld, Sydne Record, Angela L. Strecker, Lydia Beaudrot

Environmental Science and Management Faculty Publications and Presentations

Aim: Although it is recognized that ecological patterns are scale dependent, the exact scales over which specific ecological processes operate are still a matter of controversy. In particular, understanding the scales over which biotic interactions operate is critical for predicting changes in species distributions in the face of the ongoing biodiversity crisis. It has been hypothesized that biotic interactions operate predominately at fine grains, yet this conjecture has received relatively little empirical scrutiny. We use US woodpeckers as a model system to assess the relative importance of biotic interactions, environmental suitability and geographic proximity to other intraspecific occurrence sites, …


Rock Creek Restoration Macroinvertebrate Monitoring Report, Daniel Bedell Jul 2015

Rock Creek Restoration Macroinvertebrate Monitoring Report, Daniel Bedell

Environmental Science and Management Professional Master's Project Reports

Stream restoration is widely used to rebuild habitat for native fisheries, but it is not well understood how current habitat reconstruction practices affect biological diversity. Citizen Science programs have potential to provide supplemental macroinvertebrate data for effectiveness monitoring of reach-scale restoration projects but variability in training, experience and collection methods can make interpretation difficult. The Clackamas Water Environment Services Watershed Health Education Program (WHEP) is an example of a Citizen Science-based program actively collecting biological data from restored streams. The purpose of this project was to use WHEP student-collected data to detect benthic macroinvertebrate community responses to stream restoration practices. …


Investigations Of The Air-Water Interface: A Structural Analysis Of Metallic Surface Films And Aquatic Surface Films By Comparative Microscopy, Randall William Smith Jun 2015

Investigations Of The Air-Water Interface: A Structural Analysis Of Metallic Surface Films And Aquatic Surface Films By Comparative Microscopy, Randall William Smith

Dissertations and Theses

The air-water interface is an important natural boundary layer that has been neglected as an area of environmental field research. This study establishes that comparative microscopy can be an effective environmental method, and establishes that the term metallic surface films, is a more accurate descriptor than iron oxide surface films. This research shows that surface films are complex, often with layered structure, serve as habitat for significant biota, and act as a point of mineralization to several transition metal elements including manganese, iron, copper, nickel and zinc. This study demonstrates that surface films form under several conditions and can have …


Localized Ecological And Educational Effects Of Environmental Service-Learning In Portland, Oregon, Steven Matthew Braun Jun 2015

Localized Ecological And Educational Effects Of Environmental Service-Learning In Portland, Oregon, Steven Matthew Braun

Dissertations and Theses

Environmental service-learning is an intentional educational experience(s) wherein learners engage in meaningful activities designed to serve the environment. Environmental service-learning activities vary according to their learning and service goals and include ecomanagement, persuasion, legal action, economic action and political action. The purpose of this mixed methods research was to explore the ecological and educational impacts of grades 6-12 environmental education, with special attention to environmental service-learning throughout Portland, Oregon.

Ecological impacts considered restoration and conservation outcomes of several environmental service-learning programs including plant communities, soils, litter removal and trail maintenance. Educational outcomes considered aspects of environmental literacy including locus of …


Oregon Invasive Species Council Review, Robyn Draheim, Rob Fiegener, Lisa Gaines Jun 2015

Oregon Invasive Species Council Review, Robyn Draheim, Rob Fiegener, Lisa Gaines

Center for Lakes and Reservoirs Publications and Presentations

The Oregon Invasive Species Council (OISC – “Council” is also used in this report) was established by the Oregon Legislature in 2001 [ORS 570.750, formerly 561.687]. In partnership with a broad group of state, federal and local agencies, non-profit organizations, industry representatives and individuals, the Council created and maintains the means for citizens to report sightings of invasive species and a process by which this information is forwarded to appropriate agencies; works to increase citizen engagement and awareness of invasive issues; conducts educational meetings and conferences; and, administers a trust account for funding eradication and educational projects.

In 2014, the …


Herbicide Resistance: Challenges For Farmers And Implications For The Environment, George Frisvold, David E. Ervin Jun 2015

Herbicide Resistance: Challenges For Farmers And Implications For The Environment, George Frisvold, David E. Ervin

Economics Faculty Publications and Presentations

Genetically modified, herbicide resistant (HR) crops offer not only improved weed control, but also the potential to reduce soil erosion and fossil fuel use and to allow substitution toward less toxic or persistent herbicides. The widespread adoption of HR crops, however, has reduced the diversity of weed control tactics and increased ecological selection pressure for weeds resistant to dominant herbicides. This has led to a dramatic rise of HR weeds in many cropping systems. Resistant weeds threaten the sustainability of HR crops, pose environmental risks from alternative weed control practices, are altering public and private R&D programs, and necessitate new …


Experiential Knowledge And Interdisciplinary Approaches To Address Herbicide Resistance: Insights From Theory And Practice, David Shaw, David E. Ervin Jun 2015

Experiential Knowledge And Interdisciplinary Approaches To Address Herbicide Resistance: Insights From Theory And Practice, David Shaw, David E. Ervin

Economics Faculty Publications and Presentations

The exponential increase in herbicide resistant weeds around the globe poses a “wicked problem” that resists solutions developed from disciplinary science (Ervin and Jussaume; Shaw). Traditonal voluntary education and technical assistance approaches have failed to stem the advance of resistance. Scholars and practitioners recognize that improved understanding of human behavior leading to more resistant weeds must provide the foundation of knowledge for innovating more effective approaches. Principles to negotiate progress on wicked problems stress interdisciplinary approaches that integrate frontier social and natural science concepts with stakeholder experiences to discover novel approaches (Sayer et al). Standard templates to address the problem …


Type And Timing Of Stream Flow Changes In Urbanizing Watersheds In The Eastern U.S., Kristina G. Hopkins, Nathaniel B. Morse, Daniel J. Bain, Neil D. Bettez, Nancy B. Grimm, Jennifer L. Morse, Monica M. Palta Jun 2015

Type And Timing Of Stream Flow Changes In Urbanizing Watersheds In The Eastern U.S., Kristina G. Hopkins, Nathaniel B. Morse, Daniel J. Bain, Neil D. Bettez, Nancy B. Grimm, Jennifer L. Morse, Monica M. Palta

Environmental Science and Management Faculty Publications and Presentations

Linking the type and timing of hydrologic changes with patterns of urban growth is essential to identifying the underlying mechanisms that drive declines in urban aquatic ecosystems. In six urbanizing watersheds surrounding three U.S. cities (Baltimore, MD, Boston, MA, and Pittsburgh, PA), we reconstructed the history of development patterns since 1900 and assessed the magnitude and timing of stream flow changes during watershed development. Development reconstructions indicated that the majority of watershed development occurred during a period of peak population growth, typically between 1950 and 1970. Stream flow records indicated significant increases in annual frequency of high-flow events in all …


The Erosion Of Coastal Sediment And Regeneration Of Rhizophora Mangle Following Anthropogenic Disturbance On Turneffe Atoll, Belize, Heather Lyn Hayden May 2015

The Erosion Of Coastal Sediment And Regeneration Of Rhizophora Mangle Following Anthropogenic Disturbance On Turneffe Atoll, Belize, Heather Lyn Hayden

Dissertations and Theses

As communities and managers become aware of the long-term impacts of mangrove loss, estimated at 1-2% per year, interest in sediment erosion and mangrove rehabilitation has increased substantially. In this thesis project I 1) examine erosion rates within coastal fringing Rhizophora mangle ecosystems following mangrove clearing and compare these rates to accretion rates in intact mangroves; and 2) investigate the abiotic factors influencing mangrove seedling survival and regeneration of naturally colonizing R. mangle, in historic mangrove habitat after anthropogenic clearing.

Differences in erosion were compared between patches of open-coast intact and anthropogenically cleared R. mangle to quantify the sediment trapping …


The Response Of Zooplankton Communities In Montane Lakes Of Different Fish Stocking Histories To Atmospheric Nitrogen Deposition Simulations, Jeffrey Thomas Brittain May 2015

The Response Of Zooplankton Communities In Montane Lakes Of Different Fish Stocking Histories To Atmospheric Nitrogen Deposition Simulations, Jeffrey Thomas Brittain

Dissertations and Theses

Freshwater ecosystems are subject to a wide variety of stressors, which can have complex interactions and result in ecological surprises. Non-native fish introductions have drastically reduced the number of naturally fishless lakes and have resulted in cascading food web repercussions in aquatic and terrestrial habitats. Additional anthropogenic influences that result from increases in global airborne emissions also threaten wildlife habitat. Atmospheric nitrogen deposition has been recognized as an anthropogenic contributor to acidification and eutrophication of wilderness ecosystems. Planktonic communities have shown declines in response to predation and shifts in composition as a result of nutrient inputs and acidification, both of …


Effects Of Selective Logging And Roads On Instream Fine Sediments And Macroinvertebrate Assemblages In The Clackamas Basin, Oregon, Paula Elizabeth Hood May 2015

Effects Of Selective Logging And Roads On Instream Fine Sediments And Macroinvertebrate Assemblages In The Clackamas Basin, Oregon, Paula Elizabeth Hood

Dissertations and Theses

Logging and associated skid trails, haul routes, and roads can have significant impacts on the magnitude and timing of sediments in streams in forested watersheds. Loss of vegetation, soil compaction, use of heavy logging equipment, and alteration of natural hydrologic patterns within the watershed can increase landslide rates, create erosion, and generate fine sediments. Selective logging, also called thinning, is a logging practice that leaves some trees within sale units unharvested. The ecological impacts of thinning on stream ecosystems are not fully understood and need further study. My hypothesis was that macroinvertebrate assemblages would be different in streams in non-reference …


Academic Incoherence: The State Of Sustainability Literature Today, Anthony Philip Stine May 2015

Academic Incoherence: The State Of Sustainability Literature Today, Anthony Philip Stine

Student Research Symposium

The traditional tools associated with researching and presenting findings in contemporary sustainability literature include very little representation on moral forms of discourse. In the context of social sustainability this is problematic due to the inherently normative nature of the discourse. A citation analysis reveals very little representation of Christian moral environmental claims in the sustainability literature today despite growing concern amongst Christians for the state of the environment today.