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Zoonotic Disease Emergence : A Study Of Host-Pathogen-Ecosystem Dynamics, Laurie Jeanne Dizney

Dissertations and Theses

A growing body of work demonstrates that loss of biodiversity negatively impacts ecosystem functions. One function, or service, that biodiverse ecosystems provide is suppression of zoonotic diseases, which are defined as diseases carried by wildlife hosts that can spill over into human populations. Ebola, SARS, West Nile virus, Hantavirus, Avian Influenza and Lyme disease are just a few of the recently emerging zoonotic diseases. Disease suppression has been shown for Lyme disease by the dilution effect, whereby increasing species diversity decreases disease prevalence in the host populations. But does a dilution effect apply to other disease systems? To test this …

"Sustainable Development": Critical Concepts In Geography, Tyler Vick

Geography Masters Research Papers

This paper reviews significant geographic contributions to academic literature in the arenas of conservation, environmental thought, and "sustainable development", in order to understand why geographers have not been more central contributors to the sustainable development movement. A review of geographic literature reveals no lack of understanding on the "sustainable development" concept. However, the disciplines' contributions are lacking in numbers relative to published articles and in developing research and practical methods for directly benefiting the "sustainable development" movement. In fact, only a handful of geographers have made multiple literary contributions on the topic of "sustainable development."

The discipline of geography is …

Habitat And Distribution Of The Ruffed Lemur, "Varecia", North Of The Bay Of Antongil In Northeastern Madagascar, Evon R. Hekkala, Marius Rakotondratsima, Natalie Vasey

Anthropology Faculty Publications and Presentations

Here we present information on the conservation status of ruffed lemurs (Varecia) north of the Bay of Antongil in northeastern Madagascar. Two contiguous protected areas were recently established that traverse this region via blocks of forest connected by narrow forest corridors: the Masoala National Park, which expands further to the east, and the Makira Protected Area, which expands further to the west and northwest. The two extant ruffed lemurs, Varecia variegata and V. rubra, overlapped in this region historically and, on rare occasions, hybridized. As such, land north of the Bay of Antongil is a critical part …

Urban Ecology & Conservation Symposium 2006: 4th Annual -- Fostering Science And Nature In The City (Abstracts), Urban Ecosystem Research Consortium

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 …

Woodland Amphibian Distribution In Parks And Greenspaces Of The Portland, Oregon Metropolitan Area: A Multiple Scale Investigation, Laura A. Roberts

Dissertations and Theses

Loss of biodiversity due to habitat fragmentation is worldwide problem. With growing human populations and increasing urbanization, it is a necessity to conduct studies on wildlife occurring in urban areas. Currently there is a deficit of research investigating woodland amphibians in urban environments. My objectives were to describe amphibian species richness and abundance in the Portland, Oregon, Metropolitan region, and relate patterns of variation to variables at three increasingly large spatial scales: 1) local microenvironmental (i.e. amphibian/substrate interaction), (2) macrohabitat/patch (i.e. park or greenspace), and 3) landscape (surrounding parks and greenspaces). Environmental variables occurring within the three spatial scales were …

Urban Ecology & Conservation Symposium 2003: 1st Annual -- Sharing Data, Making Connections (Abstracts), Urban Ecosystem Research Consortium

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 …

Low-Income Homeownership In Portland's Albina Community: A Comparative Analysis Of Housing Quality In Market-Rate And Subsidized Houses, Carolyn Emily Collopy

Dissertations and Theses

The purpose of this study was to detem1ine which of these two options, market-rate or subsidized, offer higher quality affordable housing to low and moderate-level income households. Through field observation and GIS analysis, the study compared the structural, block, neighborhood amenity, crime, and proximity to CBD characteristics of affordable market-rate and subsidized houses in Portland's Albina Community. The study samples were approximately 100 houses per sample; market-rate houses consisted of houses that sold during 2000 for $125,000 or less, and subsidized houses were selected from housing created by three local non-profit development agencies.

General characteristics of the two samples revealed …

The Impacts Of The Introduced European Green Crab, Carcinus Maenas, On Selected Bivalves And Meiofaunal Communities, Zasha A. Bassett

Dissertations and Theses

This thesis examines the potential impact of the invasive green crab, Carcinus maenas, in Yaquina Bay, Oregon. I sampled the current extent of crab colonization in the intertidal zone of Yaquina Bay using a standardized trapping regimen in selected intertidal sites in August and September 1999. I also evaluated the potential impacts of C. maenas on the commercially important bivalve, Crassotrea gigas. Carcinus' preferred size ranges of C. gigas and other species were experimentally determined. Additionally, Carcinus species preference for C. gigas was examined in relation to two common bivalves, Mytilus trossolus and Macoma nasuta. Experiments were …

Multiple Source Pools And Dispersal Barriers For Galápagos Plant Species Distribution, J. Alan Yeakley, John F. Weishampel

Environmental Science and Management Faculty Publications and Presentations

We reexamined geographic factors explaining the number of plant species on islands in the Galápagos Archipelago. We hypothesized that plant species richness (S) was related to the number of source pools and that plant species dispersal preferentially followed direct, oceanic pathways. To test different dispersal pathways from multiple source pools, the total number of islands within a given dispersal radius (i) was posed as the sum of the number of line-of-sight islands (C_i) and of the number of islands without line-of sight connection (B_i). In partial regression analyses, controlling for nearest island area (A₂) …

Variability In Winter Mass Balance Of Northern Hemisphere Glaciers And Relations With Atmospheric Circulation, Gregory J. Mccabe, Andrew G. Fountain, Mark Dyurgerov

Geography Faculty Publications and Presentations

An analysis of variability in the winter mass balance (WMB) of 22 glaciers in the Northern Hemisphere indicates two primary modes of variability that explain 46% of the variability among all glaciers. The first mode of variability characterizes WMB variability in Northern and Central Europe and the second mode primarily represents WMB variability in northwestern North America, but also is related to variability in WMB of one glacier in Europe and one in Central Asia. These two modes of WMB variability are explained by variations in mesoscale atmospheric circulation which are driving forces of variations in surface temperature and precipitation. …

The Effects Of Urbanization And Human Disturbance Upon Plant Community Structure And Bird Species Richness, Diversity, And Abundance In A Natural Forested Area (Forest Park) In Portland, Oregon, Nancy Ellen Broshot

Dissertations and Theses

The effects of urbanization and continual human disturbance on the plant and avian communities of Forest Park and forested lands surrounding Portland, Oregon, were studied. I examined characteristics of plant and avian communities at 25 sites, 24 which were in Forest Park and surrounding areas and one which was in the Ancient Forest Preserve (old-growth stand) northwest of Forest Park. Data were analyzed using multiple regression, ANOV A, and Bonferonni/Dunn. Seven variables were selected representing different urbanization gradients. An additional covariable coded for the old-growth stand, allowing it to be used as a control.

Many tree variables, especially those related …

Gene Expression In Two Cyanobacteria, Freshwater Synechococcus Sp. Pcc 7942 And Oceanic Synechococcus Sp. Wh 7803, In Response To Ammonium, Nitrate Or Iron, Abbas Sadeghi

Dissertations and Theses

The transcriptional response of freshwater Synechococcus sp. PCC 7942 and oceanic Synechococcus sp. WH 7803 to ammonium, nitrate or iron was studied in single or multiple factor limited cultures. Both strains showed maximum production of NiR mRNA when grown in nitrate-containing media. When grown in ammonium-containing medium, they did not show any signal for NiR mRNA synthesis. The influence on the transcription of NiR mRNA by iron as sole limiting nutrient was also evaluated. Iron increased the NiR mRNA whether or not the positive effect of nitrate was already present. The hybridization signal of mRNA for the large subunit of …

Enculturing Nature, William Lloyd Cornett

Dissertations and Theses

Human activity is embedded within a myriad of seldom-acknowledged ecological relationships. Anthropology and ecology, two holistic disciplines concerned with these activities, struggle with the topic of human/nature relationships because both are grounded within larger western discourses separating human behaviors from those of the natural world. This thesis examines the histories of anthropology and ecology in the 20th Century, and the effect these disciplines have had upon the formulation of contemporary urban worldviews that are based upon the separation of humans from nature.

An Ecology Problem Book, Marc Mangel, Paul Switzer, Sarah M. Eppley

Biology Faculty Publications and Presentations

This problem book has many objectives:

• To get you to think about the course each night: do not wait until the last minute to begin working on the problems.
• To get you to deal with data. Statistics courses that you take in the future will be more meaningful once you understand the kinds of data that arise in ecological studies.
• To get you to be more comfortable with theoretical and quantitative methods. Not every ecologist uses those methods, but one should not be put off by them.
• To familiarize you with material as it appears in the professional literature.

Ecology, Wilderness Selection, And The Salmonhuckleberry Roadless Area, Jason Scot Barker

Dissertations and Theses

In the 1970s, the Forest Service used ecology in the process that led to the SalmonHuckleberry roadless area in the Mount Hood National Forest becoming a Congressionally designated Wilderness in 1984. This case study of the history of SalmonHuckleberry roadless area confirms the criticism made by environmentalists that noncommercial forest values have received much less priority than commercial uses in forest planning during the late 1960s and 1970s. This study of the area also reveals that the Forest Service's planning process was fundamentally flawed because Forest Service planners often lacked scientific data to support management decisions and downplayed the sigificnace …

The Periphyton Community Of A Second Order Subalpine Stream Following Salmon Carcass Decomposition, Jonathan Micheal Honea

Dissertations and Theses

To protect and manage Pacific Northwest salmonid stocks, sound management programs must be developed that incorporate knowledge of the ecological processes critical to their survival. One such process is the nutrient dynamic in headwater spawning streams. It is essential that we understand the trophic relationships among the spawners, the I to 3 year-old juveniles, the invertebrates, and the primary producers in these streams.

The hypothesis that I tested is that photoautotrophic production increases due to the decomposition of salmon carcasses. Increased primary production would stimulate the production of invertebrates which are an important food resource of juvenile salmonid species. The …

The Summit Vegetation Of Saddle Mountain, Oregon Coast Range, Charles Thomas Carlson

Dissertations and Theses

Saddle Mountain (1000 m) is the highest peak in the Northern Oregon Coast Range. Meadows are found to occur at and near the summit of the mountain which contain abundant wildflowers. Although the majority of these meadow species have been collected and identified in the past no formal study has been done to classify them into communities. The purpose of this study is to examine the character and origin of the plant communities located at or near the summit of Saddle Mountain. Data were collected on 4 study sites during the Summer of 1996 and analysis of the data lead …

Eco-Industrial Parks: A Case Study And Analysis Of Economic, Environmental, Technical, And Regulatory Issues, Sheila A. Martin, Keith A. Weitz, Robert A. Cushman, Aarti Sharma, Richard C. Lindrooth, Stephen R. Moran

Institute of Metropolitan Studies Publications

Despite a growing interest in and awareness of applications of industrial ecology (IE), such as eco-industrial parks (EIPs), little information is available about the potential economic and environmental benefits of EIPs, the process for successful EIP development, the important regulatory issues surrounding EIPs, or the technologies needed to support them. This report contains the results of a body of research intended to investigate and support the development of EIPs—communities of companies modeled after industrial ecosystems. EIPs can exist within defined boundaries and broader industrial ecosystems in a region. These communities consciously collaborate to enhance their economic performance through improved environmental …

Clinging To Life: Varecia Variegata Rubra And The Masoala Coastal Forests, Natalie Vasey

Anthropology Faculty Publications and Presentations

The article describes the authors field study from October 1993 to February 1995 in Madagascar, surveying coastal and riverine forests, villages, and watersheds, studying the ecology and behavior of Varecia varuegata rubra, the red ruffed lemur, and Lemur fulvus albifrons, the white fronted lemur.

Phytoplankton In Mt. St. Helens Lakes, Washington, Cynthia Fay Baker

Dissertations and Theses

Phytoplankton communities in fifteen lakes in the Mt. St. Helens area were surveyed to assess the abundance and species present. Eleven of the lakes were inside the blast zone of the 1980 eruption and four were located outside the blast zone as a comparison. The hypothesis is that lakes will cluster together based on the algal species present and that some algae will be correlated with certain environmental conditions. A cluster analysis was performed to determine if the lakes would group together based on algal abundance. There did not appear to be any distinct clustering among the study lakes, but …

Metropolitan Greenspaces: Master Plan, Metro (Or.)

Metro Collection

No abstract provided.

William A. Rockie: Seventy Years A Geographer In The West, John D. Rockie

Occasional Papers in Geography

Occasional Paper in Geography Publication No. 5

At the time of William A. Rockie's death in 1981 he was in the process of preparing a monograph for the 'Occasional Papers in Geography' series at Portland State University. The monograph was to recount his long career as a professional geographer. He had started in the late 1970's writing his recollections in a random fashion. After Rockie's death several people from the Geography Department at Portland State University discussed the unfinished work with Rockie's son, John, who agreed to assume responsibility for organizing what Rockie had written and expand on it as …

The Dynamics Of The Columbia River Estuarine Ecosystem: Volume I And Volume Ii, Creddp, Charles A. Simenstad, David A. Jay, C. David Mcintire, Willa Nehlsen, Christopher R. Sherwood, Lawrence F. Small

Civil and Environmental Engineering Faculty Publications and Presentations

Integrates results from the CREDDP studies into a comprehensive synthesis. Includes physical setting and processes; relationships between physical and biological processes and among functional groups of organisms; species, biomass and productivity per habitat type per region. Approximately 360 pages per volume.

Circulatory Processes In The Columbia River Estuary, David A. Jay

Civil and Environmental Engineering Faculty Publications and Presentations

Covers tidal circulation, density distribution, vertical mixing, salt transport, and low-frequency flow processes, with contributions to estuarine circulation theory.

Fringe Area Growth In Metropolitan Portland: An Analysis Of Space-Time Variations In Residential Housing And Land Conversion, 1970-1980, Sheku Gibril Kamara

Dissertations and Theses

Urban ecological problems have hitherto been addressed using one of two major approaches. The first has a social impetus directed at ethnic, economic and family characteristics and their relationships with the spatial distribution of urban residential housing. The second approach emphasizes the influence of the physical environment and the services available to subareas. The sociological method has had much more attention in modeling applications than the physical analytic technique. This study adopts the physical approach with a focus that is emphatic on infrastructural factors and land attributes, and their influence on the differential rates of fringe area residential growth in …

A Biogeographical Study Of Currently Identified Oregon Pseudoscorpions With An Emphasis On Western Oregon Forms, Ellen M. Benedict

Dissertations and Theses

The biogeography of the 50 currently identified Oregon species is reported from analyses of data from 2220 Berlese samples collected in a stratified, extensive sampling procedure, and from collection data on several hundred specimens from major private and public collections of pseudoscorpions. Individual species accounts including maps and data relating to geographical and seasonal distribution and habitats are provided, distributional areas and habitat types are categorized, dispersal mechanisms including examples of phoresy are presented and an illustrated key to Oregon species is given.

The Effects Of Urban-Rural Life Histories Of The Aged On Urban Adaptation, Michael R. Deshane

Dissertations and Theses

Among the major interests of students of urbanism and urbanization in the United States have been the understanding and explication of differences between urban and rural segments of American society. Coupled with this has been an attempt to theoretically delineate the effects of these differences on the social psychological adjustment of urban and rural inhabitants. The culmination of this work in sociology is to be found in Wirth's (1938) essay "Urbanism as a Way of Life." Wirth identified three major differences between urban and rural lifestyles which have been the impetus for considerable research and controversy. The three major differences …

Thermal Ecology And Movement In The Leopard Lizard, Gambelia Wislizeni, Baird And Girard, Marvin Lynn Abts

Dissertations and Theses

Thermal ecology and movement of the Leopard Lizard, G. wistizeniwere studied at Frog Spring, adjacent to the Alvord Desert, and at various locations throughout the Alvord Basin. Seasonal activity is known to occur from early May to mid-October, but abundance. gradually decreases after late July. During favorable late spring, and summer weather lizards exhibit a bimodal pattern of diel activity with some activity occurring at all hours of the day between 0600 and 1800 H. At other times activity was unimodal. Emergence was apparently largely temperature dependent and did not occur until sand temperature approximated 21°C. Retreat appeared to …

Rain: Appropriate Technology, Recycling, Video, Community, Energy, Wind, Solar, Land Use, Energy Conserving Lifestyles, Eco-Net

RAIN: Journal of Appropriate Technology

Volume 2, Number 4

Inside: Eating High and Lightly; Mega-Paper Tigers; The Great Recycling Race

RAIN began in October 1974 as a publication of ECO-NET, an environmental education network funded by the Hill Foundation and an Environmental Education grant. Its office was based in the Environmental Education Center at Portland State University. With a focus on the Pacific Northwest, particularly Oregon, RAIN originally described itself as a “bulletin board” with an “emphasis on environmental/energy related and communications kinds of information” and interested in “the evolutionary possibilities of inter-disciplinary connections.”

Interactions In The Frequencies Of Electric Organ Discharge By Eigenmannia Virescens (Sternopygidae, Pisces) During Social Behavior, Philip Gaddis

Dissertations and Theses

The extent to which individuals of Eigenmannia virescens modulate their electric organ discharge frequencies to accommodate the frequencies of others of the same species during social interactions was investigated. Recordings of the fish's discharge frequencies, taken with Tektronix 3L5 and 5L4N spectrum analyzers, showed that, although movements of up to 60 Hz in a day may be made, the frequency movements would be made more or less synchronously by all fish in the group. An apparent preference for, and a tendency of the fish to follow one another in frequency, at frequency ratios of 2:3 (a musical fifth), 3:4 (fourth), …