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Articles 121 - 150 of 154

Full-Text Articles in Natural Resources Management and Policy

Interview With Jim Labbe, Portland Audubon Society, 2011, Jim Labbe Mar 2011

Interview With Jim Labbe, Portland Audubon Society, 2011, Jim Labbe

All Sustainability History Project Oral Histories

Interview of Jim Labbe by Tony Smith on March 11th, 2011.

The interview index is available for download.


Foliar Nutrient Concentrations Related To Soil Sources Across A Range Of Sites In The Northeastern United States, Melissa S. Lucash, Ruth D. Yanai, Joel D. Blum, B. B. Park Jan 2011

Foliar Nutrient Concentrations Related To Soil Sources Across A Range Of Sites In The Northeastern United States, Melissa S. Lucash, Ruth D. Yanai, Joel D. Blum, B. B. Park

Environmental Science and Management Faculty Publications and Presentations

Understanding the supply of nutrients from various soil sources and the sensitivity of tree species to soil nutrient availability is critical for predicting the effects of declines in base cations due to acid rain and forest harvesting on forest health and productivity. We collected soil samples from 19 sites in the northeastern United States, chemically analyzed them using a sequential extraction procedure, and compared them to the chemical composition of foliage of the dominant tree species. Concentrations of Ca and Mg in foliage were correlated with exchangeable Ca and Mg concentrations in the upper mineral soil; for most tree species …


The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2010, David J. Lauten, Kathleen J. Castelein, J. Daniel Farrar, Adam A. Kotaich, Eleanor P. Gaines Dec 2010

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2010, David J. Lauten, Kathleen J. Castelein, J. Daniel Farrar, Adam A. Kotaich, Eleanor P. Gaines

Institute for Natural Resources Publications

From 8 April – 27 September 2010 we monitored the distribution, abundance and productivity of the federally Threatened Western Snowy Plover (Charadrius alexandrinus nivosus) along the Oregon coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Beach, New River, and Floras Lake. Our objectives for the Oregon coastal population in 2010 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) continue selective use of mini-exclosures (MEs) to protect nests …


Interview With Michael Burri, Us Forest Service, 2010 (Audio), Michael Burri May 2010

Interview With Michael Burri, Us Forest Service, 2010 (Audio), Michael Burri

All Sustainability History Project Oral Histories

Interview of Michael Burri by Jeff Pullen-Sayles at Sandy, Oregon on May 9th, 2010.

The interview index is available for download.


The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2009, David J. Lauten, Kathleen J. Castelein, J. Daniel Farrar, Hendrik G. Herlyn, Eleanor P. Gaines Dec 2009

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2009, David J. Lauten, Kathleen J. Castelein, J. Daniel Farrar, Hendrik G. Herlyn, Eleanor P. Gaines

Institute for Natural Resources Publications

From 3 April – 23 September 2009 we monitored the distribution, abundance and productivity of the federally Threatened Western Snowy Plover (Charadrius alexandrinus nivosus) along the Oregon coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Beach, New River, and Floras Lake. Our objectives for the Oregon coastal population in 2009 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) continue selective use of mini-exclosures (MEs) to protect nests …


Similarity Of Nutrient Uptake And Root Dimensions Of Engelmann Spruce And Subalpine Fir At Two Contrasting Sites In Colorado, Melissa S. Lucash, Ruth D. Yanai, Karis J. Mcfarlane, Sarah E. Kulpa, Dustin M. Wood Oct 2009

Similarity Of Nutrient Uptake And Root Dimensions Of Engelmann Spruce And Subalpine Fir At Two Contrasting Sites In Colorado, Melissa S. Lucash, Ruth D. Yanai, Karis J. Mcfarlane, Sarah E. Kulpa, Dustin M. Wood

Environmental Science and Management Faculty Publications and Presentations

Nutrient uptake capacity is an important parameter in modeling nutrient uptake by plants. Researchers commonly assume that uptake capacity measured for a species can be used across sites. We tested this assumption by measuring the nutrient uptake capacity of intact roots of Engelmann spruce (Picea engelmanni Parry) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) at Loch Vale Watershed and Fraser Experimental Forest in the Rocky Mountains of central Colorado. Roots still attached to the tree were exposed to one of three concentrations of nutrient solutions for time periods ranging from 1 to 96h, and solutions were analyzed for ammonium, …


Effects Of Tide Gate Replacement On Water Temperature In A Freshwater Slough In The Columbia River Estuary, Sara Ennis Oct 2009

Effects Of Tide Gate Replacement On Water Temperature In A Freshwater Slough In The Columbia River Estuary, Sara Ennis

Environmental Science and Management Professional Master's Project Reports

Dramatic declines in salmon populations in the Pacific Northwest have brought new attention to the importance of estuarine rearing habitats. Levees and tide gates used to convert estuarine wetlands into farmland have reduced available habitat by more than half of historical levels. Recent efforts to restore estuarine habitats include tide gate replacement, though this method has been poorly studied. As a key indicator of salmon habitat suitability, temperature was used to evaluate the effects of tide gate replacement in a tidally influenced freshwater slough in the Lower Columbia River estuary. Three tide gates in the largest slough on Tenasillahe Island …


Interview With Steve Cohen, Planning & Sustainable Development, 2009 (Audio), Steve Cohen Jul 2009

Interview With Steve Cohen, Planning & Sustainable Development, 2009 (Audio), Steve Cohen

All Sustainability History Project Oral Histories

Interview of Steve Cohen by Chris Stephens at Ecotrust Building, Portland, Oregon on July 28th, 2009.

The interview index is available for download.


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 Mckee Preserve Management Options At Bandon Dunes Golf Resort, Ashley Marie Edwards Jan 2009

The Mckee Preserve Management Options At Bandon Dunes Golf Resort, Ashley Marie Edwards

Environmental Science and Management Professional Master's Project Reports

The McKee Preserve is a new conservation area at Bandon Dunes Golf Resort, located on the southern Oregon coast. The Preserve is 250 acres in size and is made up of 13 different natural resource communities. One important resource is silvery phacelia (Phacelia argentea), which is a state threatened plant species and is a species of concern federally. The goal of this project was to perform plant inventories for silvery phacelia and kinnikinnick that will be used to establish a functional management plan for the Preserve. Other resources of interest to the Preserve have been included in the …


Downspout Disconnection Suitability And Incentives Analysis For The City Of Gresham, Oregon, Brian C. Fletcher Jan 2009

Downspout Disconnection Suitability And Incentives Analysis For The City Of Gresham, Oregon, Brian C. Fletcher

Environmental Science and Management Professional Master's Project Reports

The City of Gresham is developing a Downspout Disconnection Program, which encourages homeowners to disconnect their roof downspouts from the storm sewer system and divert the stormwater onto their lawn or rain garden. Downspout disconnection is being evaluated for its effectiveness to help the city meet stormwater discharge requirements in their NPDES-MS4 permit from Oregon DEQ. This study reviewed current Natural Resources Conservation Service (NRCS) soil data and developed a suitability map showing High, Medium and Low suitability zones for on-site stormwater management. To validate the map, 55 soil textural classes and 11 infiltration rates were determined at residences throughout …


Report On Wintering Western Snowy Plovers At Coos Bay North Spit And Impacts To Plovers From The North Jetty Repair Project, Winter 2009, David J. Lauten, Kathleen J. Castelein, Eleanor P. Gaines Jan 2009

Report On Wintering Western Snowy Plovers At Coos Bay North Spit And Impacts To Plovers From The North Jetty Repair Project, Winter 2009, David J. Lauten, Kathleen J. Castelein, Eleanor P. Gaines

Institute for Natural Resources Publications

The Western Snowy Plover (Charadrius alexandrinus nivosus) breeds along the coast of the Pacific Ocean in California, Oregon, and Washington and at alkaline lakes in the interior of the western United States (Page et al. 1991). Loss of habitat, predation pressures, and disturbance have caused the decline of the coastal population of Snowy Plovers and led to the listing of the Pacific Coast Population of Western Snowy Plovers as Threatened on March 5, 1993 (U.S. Fish and Wildlife Service 1993). Oregon Western Snowy Plovers are known to winter along the coast of Oregon as well as migrate to …


The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2008, David J. Lauten, Kathleen J. Castelein, David C. Bailey, Travis Lewis, Eleanor P. Gaines Dec 2008

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2008, David J. Lauten, Kathleen J. Castelein, David C. Bailey, Travis Lewis, Eleanor P. Gaines

Institute for Natural Resources Publications

From 1 April – 24 September 2008, we monitored the distribution, abundance and productivity of the federally Threatened Western Snowy Plover (Charadrius alexandrinus nivosus) along the Oregon coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Beach, and New River. Our objectives for the Oregon coastal population in 2008 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) continue selected use of miniexclosures (MEs) to protect nests from predators …


Nutrient Uptake By Intact And Disturbed Roots Of Loblolly Pine Seedlings, Melissa S. Lucash, Ruth D. Yanai, J. Devereux Joslin Jan 2008

Nutrient Uptake By Intact And Disturbed Roots Of Loblolly Pine Seedlings, Melissa S. Lucash, Ruth D. Yanai, J. Devereux Joslin

Environmental Science and Management Faculty Publications and Presentations

Most measurements of nutrient uptake use either hydroponic systems or soil-grown roots that have been disturbed by excavation. The first objective of this study was to test how root excavation affects nitrate uptake. Rates of NO3− uptake by mycorrhizal loblolly pine (Pinus taeda L.) seedlings were measured in intact sand-filled columns, hydroponics, and disturbed sand-filled columns. Total nitrate uptake in intact sand-filled columns was higher than in disturbed columns, indicating that disturbance lowers uptake. Transferring plants from the sand-filled columns to hydroponics had little effect on NO3− uptake beyond delaying uptake for an hour. The second objective of this study …


The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2007, David J. Lauten, Kathleen J. Castelein, Raya Pruner, Marvin Friel, Eleanor P. Gaines Dec 2007

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2007, David J. Lauten, Kathleen J. Castelein, Raya Pruner, Marvin Friel, Eleanor P. Gaines

Institute for Natural Resources Publications

From 3 April – 21 September 2007, we monitored the distribution, abundance and productivity of the federally Threatened Western Snowy Plover (Charadrius alexandrinus nivosus) along the Oregon coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Beach, and New River. Our objectives for the Oregon coastal population in 2007 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) continue selected use of mini-exclosures (MEs) to protect nests from predators …


Estimating Nutrient Uptake By Mature Tree Roots Under Field Conditions: Challenges And Opportunities, Melissa S. Lucash, Dave M. Eissenstat, J. Devereux Joslin, Karis J. Mcfarlane, Ruth D. Yanai Jan 2007

Estimating Nutrient Uptake By Mature Tree Roots Under Field Conditions: Challenges And Opportunities, Melissa S. Lucash, Dave M. Eissenstat, J. Devereux Joslin, Karis J. Mcfarlane, Ruth D. Yanai

Environmental Science and Management Faculty Publications and Presentations

Nutrient uptake by roots of mature trees is difficult to measure accurately under field conditions using existing methods. In this review, we discuss current techniques for measuring uptake at the root surface including excised roots, isotopic tracers, autoradiography, depletion, and lysimeters. Although these methods have provided many insights, each has drawbacks. Estimates of uptake are affected by the sampling scheme, experimental conditions, whether roots are excised or not, concentrations of ions, and the rate of efflux of ions. Microbes and mycorrhizas can also affect estimates of uptake. A greater focus on methods development is critical to advancing our understanding of …


Bridges And Barriers To Developing And Conducting Interdisciplinary Graduate-Student Team Research, Max Nielsen-Pincus, Wayde Cameron Morse, Jo Ellen Force, J. D. Wulfhorst Jan 2007

Bridges And Barriers To Developing And Conducting Interdisciplinary Graduate-Student Team Research, Max Nielsen-Pincus, Wayde Cameron Morse, Jo Ellen Force, J. D. Wulfhorst

Environmental Science and Management Faculty Publications and Presentations

Understanding complex socio-environmental problems requires specialists from multiple disciplines to integrate research efforts. Programs such as the National Science Foundation’s Integrative Graduate Education and Research Traineeship facilitate integrated research efforts and change the way academic institutions train future leaders and scientists. The University of Idaho and the Tropical Agricultural Research and Higher Education Center in Costa Rica collaborate on a joint research program focusing on biodiversity conservation and sustainable production in fragmented landscapes. We first present a spectrum of integration ranging from disciplinary to transdisciplinary across seven aspects of the research process. We then describe our experiences and lessons learned …


The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2006, David J. Lauten, Kathleen J. Castelein, Susan Weston, Krista Eucken, Eleanor P. Gaines Dec 2006

The Distribution And Reproductive Success Of The Western Snowy Plover Along The Oregon Coast - 2006, David J. Lauten, Kathleen J. Castelein, Susan Weston, Krista Eucken, Eleanor P. Gaines

Institute for Natural Resources Publications

Part of the Oregon Bidiversity Information Center Report


Koll Center Wetlands Natural Resources Maintenance Management Plan, Meredith Clayton Oct 2006

Koll Center Wetlands Natural Resources Maintenance Management Plan, Meredith Clayton

Environmental Science and Management Professional Master's Project Reports

The intention of this plan is to provide a vision and guidelines for maintaining and improving the ecological health of Koll Center Wetlands in the short and long term. Although the plan will change over time, the goal is to quantify natural resource needs spatially, temporally, and economically.

Koll Center Wetlands is part of the Greenway/Fanno Creek/Koll Center Wetlands Park complex. The nearly 13 acre park is dominated by aquatic habitats that attract a wide variety of wildlife, particularly birds. The park grounds are not easily traversed and experience limited human use, but there are many viewpoints from which the …


Estuarine Habitat Mitigation In Oregon: Policy Review, Analysis, And Recommended Improvements, Anna Buckley Apr 2006

Estuarine Habitat Mitigation In Oregon: Policy Review, Analysis, And Recommended Improvements, Anna Buckley

Environmental Science and Management Professional Master's Project Reports

The report is organized in the following manner. After the introductory chapter (Chapter 1), Chapter Two describes Oregon's current estuarine policy and related state and federal policies. Chapter Three provides an inventory of recent permitted impacts and associated estuarine resource replacement. Chapter Four consists of a brief summary of the status of estuarine ecology and restoration/mitigation, with knowledge gaps identified. Chapter Five discusses wetland functional assessment tools and options for compensatory mitigation. This chapter begins with a description of the tidal Hydrogeomorphic (HGM) assessment method, how it compares to the estuarine resource replacement rules' relative values table, and the utility …


Ecological Science And Sustainability For The 21st Century, Margaret A. Palmer, Emily S. Bernhardt, Elizabeth A. Chornesky, Scott L. Collins, Andrew P. Dobson, Clifford S. Duke, Barry D. Gold, Robert B. Jacobson, Sharon E. Kingsland, Rhonda H. Kranz, Michael J. Mappin, M. Luisa Martinez, Florenza Micheli, Jennifer L. Morse, Michael L. Pace, Mercedes Pascual, Stephen S. Palumbi, Oj Reichman, Alan R. Townsend, Monica G. Turner Feb 2005

Ecological Science And Sustainability For The 21st Century, Margaret A. Palmer, Emily S. Bernhardt, Elizabeth A. Chornesky, Scott L. Collins, Andrew P. Dobson, Clifford S. Duke, Barry D. Gold, Robert B. Jacobson, Sharon E. Kingsland, Rhonda H. Kranz, Michael J. Mappin, M. Luisa Martinez, Florenza Micheli, Jennifer L. Morse, Michael L. Pace, Mercedes Pascual, Stephen S. Palumbi, Oj Reichman, Alan R. Townsend, Monica G. Turner

Environmental Science and Management Faculty Publications and Presentations

Ecological science has contributed greatly to our understanding of the natural world and the impact of humans on that world. Now, we need to refocus the discipline towards research that ensures a future in which natural systems and the humans they include coexist on a more sustainable planet. Acknowledging that managed ecosystems and intensive exploitation of resources define our future, ecologists must play a greatly expanded role in communicating their research and influencing policy and decisions that affect the environment. To accomplish this, they will have to forge partnerships at scales and in forms they have not traditionally used. These …


Temporal Variation In Nutrient Uptake Capacity By Intact Roots Of Mature Loblolly Pine, Melissa S. Lucash, J. Devereux Joslin, Ruth D. Yanai Jan 2005

Temporal Variation In Nutrient Uptake Capacity By Intact Roots Of Mature Loblolly Pine, Melissa S. Lucash, J. Devereux Joslin, Ruth D. Yanai

Environmental Science and Management Faculty Publications and Presentations

Nutrient uptake is generally thought to exhibit a simple seasonal pattern, but few studies have measured temporal variation of nutrient uptake capacity in mature trees. We measured net uptake capacity of K, NH+ 4, NO 3 −, Mg and Ca across a range of solution concentrations by roots of mature loblolly pine at Calhoun Experimental Forest in October 2001, July 2001, and April 2002. Uptake capacity was generally lowest in July; rates in October were similar to those in April. Across a range of concentrations, antecedent nutrient solution concentrations affected the temporal patterns in uptake in July but not in …


Environmental Gradients, Community Boundaries, And Disturbance The Darlingtonia Fens Of Southwestern Oregon, Deborah A. Tolman Jan 2004

Environmental Gradients, Community Boundaries, And Disturbance The Darlingtonia Fens Of Southwestern Oregon, Deborah A. Tolman

Dissertations and Theses

The Darlingtonia fens, found on serpentine soils in southern Oregon, are distinct communities that frequently undergo dramatic changes in size and shape in response to a wide array of environmental factors. Since few systems demonstrate a balance among high water tables, shallow soils, the presence of heavy metals, and limited nutrients, conservative efforts have been made to preserve them. This dissertation investigates the role of fire on nutrient cycling and succession in three separate fens, each a different time since fire. I specifically analyze the spatial distributions of soil properties, the physical and ecological characteristics of ecotones between Jeffrey pine …


Watershed Data Organization And Project Prioritization, Joshua Darling Apr 2003

Watershed Data Organization And Project Prioritization, Joshua Darling

Environmental Science and Management Professional Master's Project Reports

The Oregon Coastal Salmon Restoration Initiative (OCSRI) (1197) is the first of several documents that have come to be known as the Oregon Plan for Salmon and watersheds (OPSW). The OCSRI indicates that protection and restoration of salmonid stocks and improvement in water quality are the main roles for state agencies within the Oregon Plan (EO09-01: 1(b)). The Oregon Plan specifies particular actions that state agencies must take to aid in salmon recovery and also directs the Governors Watershed Enhancement Board (GWEB) to help create and organize watershed councils responsible for assessing conditions and determining priorities for watershed health. A …


Urbanization And Its Relationship To Water Quality Within The Bronson Creek Watershed, Jason Cristopher Creech Apr 2003

Urbanization And Its Relationship To Water Quality Within The Bronson Creek Watershed, Jason Cristopher Creech

Environmental Science and Management Professional Master's Project Reports

A watershed analysis project was undertaken to investigate the impact of urbanization on the water quality with Bronson Creek; a small urban stream in the metropolitan area of Portland, Oregon. Total Maximum Daily Loads (TMDLs) have been established for several water quality parameters within the watershed.

Water quality data were collected at nine sampling along Bronson Creek by Clean Water Services, a local public utility charged with storm water management and water quality protection duties. Only seven water quality parameters were included in the analysis; they were 1) temperature, 2) total phosphorous, 3) ortho-phosphate, 4) ammonia, 5) total nitrogen, 6) …


Watershed Solutions: Collaborative Problem Solving For States And Communities, National Policy Consensus Center Jan 2002

Watershed Solutions: Collaborative Problem Solving For States And Communities, National Policy Consensus Center

National Policy Consensus Center Publications and Reports

In July 2002, the National Policy Consensus Center (NPCC) hosted a colloquium for people involved in watershed collaborations, academics, and other experts from government and non-profit organizations. Its aim was to identify lessons learned from successful watershed initiatives, and to develop recommendations for governors and other state officials on ways to enhance the use and effectiveness of watershed partnerships. This report is an outgrowth of that conference.

Studies on watershed collaborations are beginning to identify what makes them successful and what some of the barriers are to greater success. For example, contrary to the fears of some observers, successful collaborations …


The Impact Of Fine Sediment On Stream Macroinvertebrates In Urban And Rural Oregon Streams, Raymond S. Hoy Jan 2001

The Impact Of Fine Sediment On Stream Macroinvertebrates In Urban And Rural Oregon Streams, Raymond S. Hoy

Dissertations and Theses

Urbanization, often characterized by high impervious surface area, can result in excessive inputs of fine sediments into urban streams. Excessive fine sediments can blanket the stream bed filling the interstitial space in the substratum, which may have adverse effects on stream biota. A field survey was conducted in Oregon urban and non-urban basins to investigate the relationship between fine sediments and stream macroinvertebrates. Physical, chemical, and biological data were collected from 59 stream sites in two urban and two rural streams. The stream sites fulfilled a continuous sediment gradient, which ranged from a low of 2% of fine sediment in …


Survey Of Aquatic Plants In Corps Of Engineers Reservoirs, Kimberly D. Walker, Mark D. Sytsma Jan 2000

Survey Of Aquatic Plants In Corps Of Engineers Reservoirs, Kimberly D. Walker, Mark D. Sytsma

Center for Lakes and Reservoirs Publications and Presentations

A survey of aquatic plants in a selected Corps of Engineers reservoirs in Oregon was conducted. Cottage Grove, Dorena, Fern Ridge, Dexter and Willow Creek Reservoirs contained abundant aquatic plants. Potamogeton pectinatus and Potamogeton epihydrous were the most common native plant species. Myriophyllum aquaticum and Potamogeton crispus were the most widespread nonnative plants. Species richness in the reservoirs was correlated with trophic status and basin morphology. Shallow reservoirs that included extensive areas of nutrient-rich sediments that were historic flood plain soils supported the greatest biomass and number of species. Mesotrophic reservoirs had lower species diversity. Oligotrophic reservoirs with steep basin …


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 Jan 1999

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 …


Mechanisms Of Pentachlorophenol Induced Charge Transport In Lipid Membranes, William Charles Brown Jan 1996

Mechanisms Of Pentachlorophenol Induced Charge Transport In Lipid Membranes, William Charles Brown

Dissertations and Theses

Pentachlorophenol (PCP) is one of the prominent environmental pollutant that has penetrated into food chain and is present in humans. Health concerns have been raised since daily intake of PCP by the US population is estimated to be 16-19 µg. PCP facilitates dissipation of electrochemical potential gradients of hydrogen ions across energy transducing membranes, which are the energy sources for the conversion of adenosine diphosphate into adenosine triphosphate. Closely linked to these dissipative effects is the development of electrical conductivity in lipid membranes, induced by the presence of PCP. Three modes of PCP - induced membrane electrical conductivity were theoretically …