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Natural Resources and Conservation

Portland State University

Dissertations and Theses

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Articles 1 - 12 of 12

Full-Text Articles in Physical Sciences and Mathematics

The Impact Of Infrastructure On Habitat Connectivity For Wildlife, Leslie Lynne Bliss-Ketchum Mar 2019

The Impact Of Infrastructure On Habitat Connectivity For Wildlife, Leslie Lynne Bliss-Ketchum

Dissertations and Theses

While roads can present weak to complete barriers to wildlife, depending on the animal and traffic volume, mitigations such as under-crossings and green bridges on highways at least partially increase the permeability of the landscape to some of these species. The few studies evaluating the effectiveness of these structures for at least three years typically focused on a single species. Here, we monitored the crossing structure under Boeckman Road, in Wilsonville Oregon, for wildlife activity across summer seasons for ten years, since construction of the road and subsequent opening to traffic. This long-term multi-species dataset, which includes monitoring when the …


Removing Dams, Constructing Science: Watershed Restoration Through A Socio-Eco-Technical Systems Lens, Zbigniew Jakub Grabowski Aug 2018

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 …


Ecosystem Recovery In Estuarine Wetlands Of The Columbia River Estuary, Sarah Ann Kidd Jun 2017

Ecosystem Recovery In Estuarine Wetlands Of The Columbia River Estuary, Sarah Ann Kidd

Dissertations and Theses

In the restoration of tidal wetland ecosystems, potential drivers of plant community development range from biotic controls (e.g. plant competition, seed dispersal) to abiotic controls (e.g. tidal flooding, salinity levels). How these controls influence the success of tidal wetland restoration are only partly understood, but have important implications for wetland habitat recovery. Specifically, the extent to which the existing native and non-native seed banks in tidally reconnected wetlands interact with these controls is not clear, yet the potential success of passive restoration methods depends upon this understanding.

For a 54-year chronosequence of eleven tidal wetland restoration sites in the Lower …


Using Critical Physical Geography To Map The Unintended Consequences Of Conservation Management Programs, Melanie Malone Jun 2017

Using Critical Physical Geography To Map The Unintended Consequences Of Conservation Management Programs, Melanie Malone

Dissertations and Theses

A variety of conservation trends have gained and lost favor throughout the years in agriculture, with U.S. Farm Bills often influencing what conservation practices are implemented by farming communities throughout the U.S. This dissertation focuses on the unintended consequences of conservation management practices in the Fifteenmile Watershed of Wasco County, Oregon. Specifically, I seek to address how farmer enrollment in various conservation techniques, loosely defined as no-till agriculture, has affected soil and water quality through the increased use of herbicide, and subsequently rendered ecological and human health vulnerable. Using a critical physical geography framework, I address both the biophysical factors …


Relationships That Extend Beyond The Fence-Line: Private Landowner Attitudes And Interest In Conservation Easements, Ashley Lyn Vizek May 2016

Relationships That Extend Beyond The Fence-Line: Private Landowner Attitudes And Interest In Conservation Easements, Ashley Lyn Vizek

Dissertations and Theses

Private land conservation provides an opportunity to address problems of habitat fragmentation and biodiversity loss caused by an increase in the development and parcelization of private land. Conservation easements (CEs) are an innovative tool used by land trusts to protect significant natural qualities of private land in perpetuity, while also allowing the land to remain in private ownership. Traditionally, property represents an individualistic relationship, however, CEs redefine this relationship by seeking to maximize the overlap in private and public goods in property. In this study, I explore the relationship between the common good and private property through an analysis of …


Evaluation Of Phase Change Materials For Cooling In A Super-Insulated Passive House, Jeffrey Stephen Lauck Oct 2013

Evaluation Of Phase Change Materials For Cooling In A Super-Insulated Passive House, Jeffrey Stephen Lauck

Dissertations and Theses

Due to factors such as rising energy costs, diminishing resources, and climate change, the demand for high performance buildings is on the rise. As a result, several new building standards have emerged including the Passive House Standard, a rigorous energy-use standard based on a super-insulated and very tightly sealed building envelope. The standard requires that that air infiltration is less than or equal to 0.6 air changes per hour at a 50 Pascal pressure difference, annual heating energy is less than or equal to 15kWh/m2, and total annual source energy is less than or equal to 120 kWh/m2. A common …


Social-Ecological Dynamics Of Coral Reef Resource Use And Management, Sarah J. Freed Jul 2013

Social-Ecological Dynamics Of Coral Reef Resource Use And Management, Sarah J. Freed

Dissertations and Theses

This dissertation investigates social and ecological factors that facilitate effective management of coral reefs as social-ecological systems. Meta-analytical and field-based methods were employed to examine current management challenges and identify strategies that improve management effectiveness and coral reef health. A meta-analysis was used to evaluate biological indicators of reef health in relation to the types of fishing regulations in place (no-take areas, gear restriction areas, and periodic closures) and the actor groups (community-based, co-management, state, private) involved in management efforts for coral reef fisheries throughout the world. Other than enhancement of fish biomass within no-take areas that was significantly greater …


Preserving Nature Through Film: Wilderness Alps Of Stehekin And The North Cascades, 1956-1968, Nicolas Timothy Bergmann Jun 2013

Preserving Nature Through Film: Wilderness Alps Of Stehekin And The North Cascades, 1956-1968, Nicolas Timothy Bergmann

Dissertations and Theses

On March 22, 1958 David Brower's film Wilderness Alps of Stehekin premiered to an audience of conservationists in Seattle, Washington. Almost two years in the making, the thirty-one minute film advocated the preservation of nature in Washington's North Cascades through the creation of a national park. Over the next decade, Wilderness Alps of Stehekin became the most influential publicity tool in the struggle to preserve the North Cascades. Because of the region's geographic isolation, the film was the first time many people throughout the nation were exposed to the scenic grandeur of the area. Images of craggy peaks and colorful …


Development Of Dynamic Thermal Performance Metrics For Eco-Roof Systems, Seth Sinclair Moody Jan 2013

Development Of Dynamic Thermal Performance Metrics For Eco-Roof Systems, Seth Sinclair Moody

Dissertations and Theses

In order to obtain credit for an eco-roof in building energy load calculations the steady state and time-varying thermal properties (thermal mass with evapotranspiration) must be fully understood. The following study presents results of experimentation and modeling in an effort to develop dynamic thermal mass performance metrics for eco-roof systems. The work is focused on understanding the thermal parameters (foliage & soil) of an eco-roof, further validation of the EnergyPlus Green Roof Module and development of a standardized metric for assessing the time-varying thermal benefits of eco-roof systems that can be applied across building types and climate zones. Eco-roof foliage, …


The Role Of Habitat Restoration And Conservation In The Changing Socio-Economic Conditions Of Grant County, Oregon, Kristen Lauren Senkyr Mar 2012

The Role Of Habitat Restoration And Conservation In The Changing Socio-Economic Conditions Of Grant County, Oregon, Kristen Lauren Senkyr

Dissertations and Theses

Habitat restoration has socio-economic as well as biophysical impacts. In Grant County, Oregon a recent influx of funding and technical resources for habitat restoration has led to focused monitoring efforts there to better understand the impacts. This study explores how local land use and land management practices are changing in Grant County as a result of restoration and other drivers. In-depth interviews were conducted with 17 landowners, land managers, and long time residents to document the change they have observed and identify how they are adapting. The results suggest that many interconnected social, economic, and ecological changes have taken place …


Vegetation, Environmental Characteristics, And Their Relationships: Variation Within The Annually Flooded Riparian Zones Of The John Day River Basin, Oregon, Samuel J. Hartsfield Feb 2009

Vegetation, Environmental Characteristics, And Their Relationships: Variation Within The Annually Flooded Riparian Zones Of The John Day River Basin, Oregon, Samuel J. Hartsfield

Dissertations and Theses

I hypothesized that vegetation and physical environmental characteristics would differ between the upper and lower extents of the annually flooded riparian zone on the John Day River, and that relationships between species and environmental variables would display differences between these two zones. Vegetation, environmental variables, and relationships between them were assessed for the entire annually flooded riparian zone, and for the proposed upper and lower zones. Data were collected from 60 one-square-meter quadrats: 30 in each the upper and lower zones. Sites were randomly selected and located so that flood duration was roughly equal at all sites within each zone. …


The Resurrection Of A River: The Umatilla And Its Salmon, Christopher Ward Shelley Mar 2002

The Resurrection Of A River: The Umatilla And Its Salmon, Christopher Ward Shelley

Dissertations and Theses

Until the 1990s, salmon had been extinct from the Umatilla River for over 70 years. The struggle to bring salmon back to this river is a compelling story that exemplifies some of the new relationships in Columbia River Basin salmon management.

The Umatilla River and the disappearance of its salmon was a local issue. Irrigation interests had used the river so thoroughly it ceased to flow during the late summer and fall months-precisely when salmon needed it for migration. The Confederated Tribes of the Umatilla Indian Reservation saw decided that they would change that: they would figure out a way …