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• 1. [Article] Residential Solar Photovoltaics: A Financial Decision Support Tool for Northwestern Oregon

  This paper describes the benefits of the utilization of solar photovoltaics (PV) in northwestern Oregon and describes a newly developed interactive financial decision support model created for residential ...

  Citation × Citation Citation Abstract Copy Title: Residential Solar Photovoltaics: A Financial Decision Support Tool for Northwestern Oregon Author: Brand, Marius, Easton, John, Sairafi, Badr, Sughi, Hithem, Jan, Fahad Year: 2008 This paper describes the benefits of the utilization of solar photovoltaics (PV) in northwestern Oregon and describes a newly developed interactive financial decision support model created for residential PV installation in northwestern Oregon. Advantages of this model over existing standards include fewer assumptions made regarding locality-specific circumstances, including utility rate increase forecasts, local incentive and tax credit information, region specific electricity generation efficiencies, and the provision of unique inputs and outputs such as user-defined financing options and variable sensitivity analysis. Title: Residential Solar Photovoltaics: A Financial Decision Support Tool for Northwestern Oregon Author: Brand, Marius, Easton, John, Sairafi, Badr, Sughi, Hithem, Jan, Fahad Year: 2008 This paper describes the benefits of the utilization of solar photovoltaics (PV) in northwestern Oregon and describes a newly developed interactive financial decision support model created for residential PV installation in northwestern Oregon. Advantages of this model over existing standards include fewer assumptions made regarding locality-specific circumstances, including utility rate increase forecasts, local incentive and tax credit information, region specific electricity generation efficiencies, and the provision of unique inputs and outputs such as user-defined financing options and variable sensitivity analysis. Close

• 2. [Article] Indicators of the Metroscape: Self-Sufficiency

  Overview of annual median income and self-sufficiency standards for various household types in 2014, for several Oregon counties in Northwestern Oregon.

  Citation × Citation Citation Abstract Copy Title: Indicators of the Metroscape: Self-Sufficiency Author: Institute of Portland Metropolitan Studies Year: 2015 Overview of annual median income and self-sufficiency standards for various household types in 2014, for several Oregon counties in Northwestern Oregon. Title: Indicators of the Metroscape: Self-Sufficiency Author: Institute of Portland Metropolitan Studies Year: 2015 Overview of annual median income and self-sufficiency standards for various household types in 2014, for several Oregon counties in Northwestern Oregon. Close

• 3. [Article] Stratigraphic relationships of the Tillamook Volcanics and the Cowlitz Formation in the upper Nehalem River-Wolf Creek area, northwestern Oregon

  The upper Nehalem River-Wolf Creek area is located on the northeastern flank of the Tillamook Highlands in the northern Oregon Coast Range. Three rock stratigraphic units underlie the thesis area, and ...

  Citation × Citation Citation Abstract Copy Title: Stratigraphic relationships of the Tillamook Volcanics and the Cowlitz Formation in the upper Nehalem River-Wolf Creek area, northwestern Oregon Author: Jackson, Michael Keith Year: 1983 The upper Nehalem River-Wolf Creek area is located on the northeastern flank of the Tillamook Highlands in the northern Oregon Coast Range. Three rock stratigraphic units underlie the thesis area, and these units range from late Eocene to Oligocene in age. Title: Stratigraphic relationships of the Tillamook Volcanics and the Cowlitz Formation in the upper Nehalem River-Wolf Creek area, northwestern Oregon Author: Jackson, Michael Keith Year: 1983 The upper Nehalem River-Wolf Creek area is located on the northeastern flank of the Tillamook Highlands in the northern Oregon Coast Range. Three rock stratigraphic units underlie the thesis area, and these units range from late Eocene to Oligocene in age. Close

• 4. [Article] A stratigraphic and geochemical investigation of ferruginous bauxite deposits in the Salem Hills, Marion County, Oregon

  Pacific Northwest ferruginous bauxite deposits have formed in four main areas of northwestern Oregon and southwestern Washington by laterization of flows of the Columbia River Basalt Group (CRBG). The ...

  Citation × Citation Citation Abstract Copy Title: A stratigraphic and geochemical investigation of ferruginous bauxite deposits in the Salem Hills, Marion County, Oregon Author: Hoffman, Charles William Year: 1981 Pacific Northwest ferruginous bauxite deposits have formed in four main areas of northwestern Oregon and southwestern Washington by laterization of flows of the Columbia River Basalt Group (CRBG). The deposits, averaging 36.3% Al2O3 , 31.8% Fe2O3 , and 5.9% Sio2, generally occur near the surface of hilltops in gently rolling areas. Two very different views have been advanced regarding the setting in which the deposits have formed. The first hypothesis calls for a blanket-type laterization by erosion of much of the original deposit upon uplift and dissection of the area. Title: A stratigraphic and geochemical investigation of ferruginous bauxite deposits in the Salem Hills, Marion County, Oregon Author: Hoffman, Charles William Year: 1981 Pacific Northwest ferruginous bauxite deposits have formed in four main areas of northwestern Oregon and southwestern Washington by laterization of flows of the Columbia River Basalt Group (CRBG). The deposits, averaging 36.3% Al2O3 , 31.8% Fe2O3 , and 5.9% Sio2, generally occur near the surface of hilltops in gently rolling areas. Two very different views have been advanced regarding the setting in which the deposits have formed. The first hypothesis calls for a blanket-type laterization by erosion of much of the original deposit upon uplift and dissection of the area. Close

• 5. [Article] Scappoose School District Population and Enrollment Forecasts, 2006-07 to 2020-21

  The Scappoose School District (SSD) in northwestern Oregon serves the City of Scappoose and the southeastern portion of Columbia County, as well as the extreme northwestern portion of Multnomah County ...

  Citation × Citation Citation Abstract Copy Title: Scappoose School District Population and Enrollment Forecasts, 2006-07 to 2020-21 Author: Portland State University. Population Research Center, Rynerson, Charles, Siu, Vivian Year: 2006 The Scappoose School District (SSD) in northwestern Oregon serves the City of Scappoose and the southeastern portion of Columbia County, as well as the extreme northwestern portion of Multnomah County and a small piece of Washington County. The area served by the District has experienced population growth in recent years, but overall school enrollment losses in two of the past five years have negated the gains in the other three years. This report presents the results of a forecast conducted by the Portland State University Population Research Center (PRC) indicating that SSD enrollment will increase during the next fifteen years, with relatively slow growth in the first five years and faster growth during the 2010 to 2020 period. PRC’s methodology links enrollment trends with the area’s population dynamics. Population and housing are closely related to access to jobs. In the context of expected employment, population, and housing growth, enrollment is likely to increase at all grade levels. Title: Scappoose School District Population and Enrollment Forecasts, 2006-07 to 2020-21 Author: Portland State University. Population Research Center, Rynerson, Charles, Siu, Vivian Year: 2006 The Scappoose School District (SSD) in northwestern Oregon serves the City of Scappoose and the southeastern portion of Columbia County, as well as the extreme northwestern portion of Multnomah County and a small piece of Washington County. The area served by the District has experienced population growth in recent years, but overall school enrollment losses in two of the past five years have negated the gains in the other three years. This report presents the results of a forecast conducted by the Portland State University Population Research Center (PRC) indicating that SSD enrollment will increase during the next fifteen years, with relatively slow growth in the first five years and faster growth during the 2010 to 2020 period. PRC’s methodology links enrollment trends with the area’s population dynamics. Population and housing are closely related to access to jobs. In the context of expected employment, population, and housing growth, enrollment is likely to increase at all grade levels. Close

• 6. [Article] The Making of Seaside’s “Indian Place”: Contested and Enduring Native Spaces on the Nineteenth Century Oregon Coast

  During the mid nineteenth century, non-Native settlement and activities disrupted and changed historic Chinook and Clatsop communities at the mouth of the Columbia River. Indian Place in what would be ...

  Citation × Citation Citation Abstract Copy Title: The Making of Seaside’s “Indian Place”: Contested and Enduring Native Spaces on the Nineteenth Century Oregon Coast Author: Deur, Douglas Year: 2016 During the mid nineteenth century, non-Native settlement and activities disrupted and changed historic Chinook and Clatsop communities at the mouth of the Columbia River. Indian Place in what would be Seaside, Oregon, became home to a number of displaced peoples and an enclave where “the living gathered with the remains of the dead,” for “modest protection from the apocalyptic changes that so radically disrupted tribal lands, lives, and worldviews.” Douglas Deur documents tribal migration to the Indian Place during the late nineteenth and early twentieth centuries and calls attention to many of its significant early residents. Transitional communities such as Indian Place, Deur attests, “defined the nineteenth- and early-twentieth-century Native experience in northwestern Oregon and beyond.” While the Indian Place no longer exists, it remains an “important [conduit] for tribal cultural knowledge, values, and practices that endure today.” Title: The Making of Seaside’s “Indian Place”: Contested and Enduring Native Spaces on the Nineteenth Century Oregon Coast Author: Deur, Douglas Year: 2016 During the mid nineteenth century, non-Native settlement and activities disrupted and changed historic Chinook and Clatsop communities at the mouth of the Columbia River. Indian Place in what would be Seaside, Oregon, became home to a number of displaced peoples and an enclave where “the living gathered with the remains of the dead,” for “modest protection from the apocalyptic changes that so radically disrupted tribal lands, lives, and worldviews.” Douglas Deur documents tribal migration to the Indian Place during the late nineteenth and early twentieth centuries and calls attention to many of its significant early residents. Transitional communities such as Indian Place, Deur attests, “defined the nineteenth- and early-twentieth-century Native experience in northwestern Oregon and beyond.” While the Indian Place no longer exists, it remains an “important [conduit] for tribal cultural knowledge, values, and practices that endure today.” Close

• 7. [Article] Geophysical and geochemical analyses of selected Miocene coastal basalt features, Clatsop County, Oregon

  The proximity of Miocene Columbia River basalts to the "locally-erupted" coastal Miocene basalts in northwestern Oregon, and the compelling similarities between the two groups, suggest that the coastal ...

  Citation × Citation Citation Abstract Copy Title: Geophysical and geochemical analyses of selected Miocene coastal basalt features, Clatsop County, Oregon Author: Pfaff, Virginia Josette Year: 1980 The proximity of Miocene Columbia River basalts to the "locally-erupted" coastal Miocene basalts in northwestern Oregon, and the compelling similarities between the two groups, suggest that the coastal basalts, rather than being locally erupted, may be the westward extension of plateau basalts derived from eastern Oregon and Washington. The local-origin hypothesis is based largely on the interpretation of coastal dikes and sills as representing vent areas; however, a complex mechanism, as yet unsatisfactorily defined, would be required to cause the eruption of virtually identical magmas simultaneously from source areas 500 km apart. This study, therefore, has investigated the coastal basalt intrusions both laterally and vertically. Geochemical and paleomagnetic analysis was used to determine the occurrence and distribution of basalt units; gravity surveys enabled an examination of the subsurface extensions of basalt intrusions in sedimentary rocks. Title: Geophysical and geochemical analyses of selected Miocene coastal basalt features, Clatsop County, Oregon Author: Pfaff, Virginia Josette Year: 1980 The proximity of Miocene Columbia River basalts to the "locally-erupted" coastal Miocene basalts in northwestern Oregon, and the compelling similarities between the two groups, suggest that the coastal basalts, rather than being locally erupted, may be the westward extension of plateau basalts derived from eastern Oregon and Washington. The local-origin hypothesis is based largely on the interpretation of coastal dikes and sills as representing vent areas; however, a complex mechanism, as yet unsatisfactorily defined, would be required to cause the eruption of virtually identical magmas simultaneously from source areas 500 km apart. This study, therefore, has investigated the coastal basalt intrusions both laterally and vertically. Geochemical and paleomagnetic analysis was used to determine the occurrence and distribution of basalt units; gravity surveys enabled an examination of the subsurface extensions of basalt intrusions in sedimentary rocks. Close

• 8. [Article] Long Trails Project: Identifying Opportunities, Solving Problems, and Exploring Implementation

  This document presents the final report of the Long Trails Project, a partnership with the Oregon Parks Department and USP 549: Regional Planning and Metropolitan Growth Management, a course offered to ...

  Citation × Citation Citation Abstract Copy Title: Long Trails Project: Identifying Opportunities, Solving Problems, and Exploring Implementation Author: Portland State University Year: 2012 This document presents the final report of the Long Trails Project, a partnership with the Oregon Parks Department and USP 549: Regional Planning and Metropolitan Growth Management, a course offered to graduate planning students in the Toulan School of Urban Studies and Planning at Portland State University. It is divided into 5 sections: (1.) History of Long Trails and Regional Trail Networks (2.) Long Trails in Northwestern Oregon (3.) The Demand for Long Trails-based Recreation (4.) Long Trails and Community Economic Development (5.) Long Trails Implementation. This technical report is edited by Dr. Ethan Seltzer Title: Long Trails Project: Identifying Opportunities, Solving Problems, and Exploring Implementation Author: Portland State University Year: 2012 This document presents the final report of the Long Trails Project, a partnership with the Oregon Parks Department and USP 549: Regional Planning and Metropolitan Growth Management, a course offered to graduate planning students in the Toulan School of Urban Studies and Planning at Portland State University. It is divided into 5 sections: (1.) History of Long Trails and Regional Trail Networks (2.) Long Trails in Northwestern Oregon (3.) The Demand for Long Trails-based Recreation (4.) Long Trails and Community Economic Development (5.) Long Trails Implementation. This technical report is edited by Dr. Ethan Seltzer Close

• 9. [Article] Geochemical Evolution of Ferruginous Bauxite Deposits in Northwestern Oregon and Southwestern Washington

  Ferruginous bauxite deposits developed from flows of the Columbia River Basalt Group in northwestern Oregon and southwestern Washington. Samples of the iron pisolite and the gibbsite nodular zones from ...

  Citation × Citation Citation Abstract Copy Title: Geochemical Evolution of Ferruginous Bauxite Deposits in Northwestern Oregon and Southwestern Washington Author: Fassio, Joseph Michael Year: 1990 Ferruginous bauxite deposits developed from flows of the Columbia River Basalt Group in northwestern Oregon and southwestern Washington. Samples of the iron pisolite and the gibbsite nodular zones from the upper portion of the weathering profile of drill core from Columbia County, Oregon and Cowlitz County, Washington, were analyzed by instrumental neutron activation. The mineralogy was determined using Xray diffraction and Mossbauer spectroscopy. The gibbsite nodular zone is above the clay-rich saprolite or relic basalt zone. The nodules contain relic vesicles and well preserved relic plagioclase microlites. Gibbsite occurs with poorly crystalline goethite and hematite in the gibbsite nodular zone. Clays are absent in this part of the profile . The iron pisolite zone is at the top of the profile above the gibbsite nodular zone. Both maghemite and goethite pisolites occur in the lower part of the zone while maghemite pisolites are dominant in the upper part of the pisolite zone. The parent flow is the Frenchman Springs Member of the Wanapum Basalt for the Columbia County profile and the Pomona Member of the Saddle Mountains Basalt for the Cowlitz County profile. Distribution of the major, minor and trace elements through the profile shows three distinct sympathetic patterns consisting of lanthanide elements and Na; As, Sbi Th, Hf, and Ta; and transition metals Fe, Ti, V, and Cr. Ratios between the high-field strength elements Ta and Hf are nearly constant through the profile, and Hf appears to be the least mobile elements of the elements analyzed in the profile. Ratios of other elements were calculated against Hf, based on the assumption that it has remained largely immobile during weathering, to show element enrichment and depletion in the profile independent of mass-volume changes. Transition metals and Al show a progressive depletion through the upper gibbsite nodular and iron pisolite zone due to leaching in the profile. Lanthanide elements (except Ce), As, and Sb show an obvious enrichment in the iron pisolite zone relative to the gibbsite nodular zone. Volume reduction during weathering was calculated based on the immobility of Hf. In the gibbsite nodular zone, the volume reduction calculated for bulk samples is greater than for gibbsite nodule separates suggesting that a greater volume reduction occurred the matrix material surrounding the nodules. Ratios between gibbsite nodules and parent basalt of the immobile elements Hf, Ta, Fe, Ti, Th and Cr suggest that the nodules, where the relic textures are preserved, have undergone volume reduction. Based on the immobility of Hf, the gibbsite nodules lost approximately 40% of the original volume. The volume factors based on the immobility of Hf show that the pisolite zone experienced a greater volume reduction than the gibbsite nodular zone. Absolute gains and losses relative to the parent basalt show the following relative order of depletion: Na > La > Eu > Sm > Co > Mn > Ce > Sc > Ta > V > Cr > Lu > Th > Fe > Ga > Al. The lesser mobility of Ce and Lu relative to other lanthanide elements suggests fractionation of lanthanide elements in the bauxite profile. Aluminum is both enriched and depleted at different depths in the gibbsite nodular zone suggesting that Al is mobilized from the matrix and possibly the pisolite zone into Al enriched gibbsite nodules. Volume reduction and destruction of relic textures in the pisolite zone is accompanied by small-scale mobilization of Th, Cr, Fe, Hf, Ga, Sc, and Ta during the formation of iron pisolites. Formation of the iron pisolite zone above the gibbsite nodular zone may indicate a change in climate from a heavy year round to a seasonal rainfall pattern. Title: Geochemical Evolution of Ferruginous Bauxite Deposits in Northwestern Oregon and Southwestern Washington Author: Fassio, Joseph Michael Year: 1990 Ferruginous bauxite deposits developed from flows of the Columbia River Basalt Group in northwestern Oregon and southwestern Washington. Samples of the iron pisolite and the gibbsite nodular zones from the upper portion of the weathering profile of drill core from Columbia County, Oregon and Cowlitz County, Washington, were analyzed by instrumental neutron activation. The mineralogy was determined using Xray diffraction and Mossbauer spectroscopy. The gibbsite nodular zone is above the clay-rich saprolite or relic basalt zone. The nodules contain relic vesicles and well preserved relic plagioclase microlites. Gibbsite occurs with poorly crystalline goethite and hematite in the gibbsite nodular zone. Clays are absent in this part of the profile . The iron pisolite zone is at the top of the profile above the gibbsite nodular zone. Both maghemite and goethite pisolites occur in the lower part of the zone while maghemite pisolites are dominant in the upper part of the pisolite zone. The parent flow is the Frenchman Springs Member of the Wanapum Basalt for the Columbia County profile and the Pomona Member of the Saddle Mountains Basalt for the Cowlitz County profile. Distribution of the major, minor and trace elements through the profile shows three distinct sympathetic patterns consisting of lanthanide elements and Na; As, Sbi Th, Hf, and Ta; and transition metals Fe, Ti, V, and Cr. Ratios between the high-field strength elements Ta and Hf are nearly constant through the profile, and Hf appears to be the least mobile elements of the elements analyzed in the profile. Ratios of other elements were calculated against Hf, based on the assumption that it has remained largely immobile during weathering, to show element enrichment and depletion in the profile independent of mass-volume changes. Transition metals and Al show a progressive depletion through the upper gibbsite nodular and iron pisolite zone due to leaching in the profile. Lanthanide elements (except Ce), As, and Sb show an obvious enrichment in the iron pisolite zone relative to the gibbsite nodular zone. Volume reduction during weathering was calculated based on the immobility of Hf. In the gibbsite nodular zone, the volume reduction calculated for bulk samples is greater than for gibbsite nodule separates suggesting that a greater volume reduction occurred the matrix material surrounding the nodules. Ratios between gibbsite nodules and parent basalt of the immobile elements Hf, Ta, Fe, Ti, Th and Cr suggest that the nodules, where the relic textures are preserved, have undergone volume reduction. Based on the immobility of Hf, the gibbsite nodules lost approximately 40% of the original volume. The volume factors based on the immobility of Hf show that the pisolite zone experienced a greater volume reduction than the gibbsite nodular zone. Absolute gains and losses relative to the parent basalt show the following relative order of depletion: Na > La > Eu > Sm > Co > Mn > Ce > Sc > Ta > V > Cr > Lu > Th > Fe > Ga > Al. The lesser mobility of Ce and Lu relative to other lanthanide elements suggests fractionation of lanthanide elements in the bauxite profile. Aluminum is both enriched and depleted at different depths in the gibbsite nodular zone suggesting that Al is mobilized from the matrix and possibly the pisolite zone into Al enriched gibbsite nodules. Volume reduction and destruction of relic textures in the pisolite zone is accompanied by small-scale mobilization of Th, Cr, Fe, Hf, Ga, Sc, and Ta during the formation of iron pisolites. Formation of the iron pisolite zone above the gibbsite nodular zone may indicate a change in climate from a heavy year round to a seasonal rainfall pattern. Close

• 10. [Article] Winter Precipitation Intensity and ENSO/PDO Variability in the Willamette Valley of Oregon

  There is growing concern about the effects of inter-annual climatic variability, such as the El-Niño Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO), on regional hydrology and water ...

  Citation × Citation Citation Abstract Copy Title: Winter Precipitation Intensity and ENSO/PDO Variability in the Willamette Valley of Oregon Author: Praskievicz, Sarah, Chang, Heejun Year: 2009 There is growing concern about the effects of inter-annual climatic variability, such as the El-Niño Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO), on regional hydrology and water resources. We analyzed patterns of wintertime precipitation intensity, using both simple intensity and number of heavy precipitation days per year, for eight stations in northwestern Oregon’s Willamette Valley for the period 1972–2006, and examined the separate and combined influence of ENSO and PDO on precipitation intensity. The analysis was accomplished using Kendall’s tau and analysis of variance (ANOVA) to determine differences in precipitation intensity among combinations of positive and negative ENSO and PDO phases. The results suggest that the relation between ENSO phase and precipitation intensity is negative in November and positive in April, while the relation between PDO and intensity is negative and strongest in January and March. These varying seasonal associations with ENSO/PDO phase may be related to the Willamette Valley’s location in the transitional zone between positive and negative El Niño response and to the moderating effects of out-of-phase ENSO/PDO. This seasonal variability of heavy rainfall has implications for the quantity and quality of regional water resources. Title: Winter Precipitation Intensity and ENSO/PDO Variability in the Willamette Valley of Oregon Author: Praskievicz, Sarah, Chang, Heejun Year: 2009 There is growing concern about the effects of inter-annual climatic variability, such as the El-Niño Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO), on regional hydrology and water resources. We analyzed patterns of wintertime precipitation intensity, using both simple intensity and number of heavy precipitation days per year, for eight stations in northwestern Oregon’s Willamette Valley for the period 1972–2006, and examined the separate and combined influence of ENSO and PDO on precipitation intensity. The analysis was accomplished using Kendall’s tau and analysis of variance (ANOVA) to determine differences in precipitation intensity among combinations of positive and negative ENSO and PDO phases. The results suggest that the relation between ENSO phase and precipitation intensity is negative in November and positive in April, while the relation between PDO and intensity is negative and strongest in January and March. These varying seasonal associations with ENSO/PDO phase may be related to the Willamette Valley’s location in the transitional zone between positive and negative El Niño response and to the moderating effects of out-of-phase ENSO/PDO. This seasonal variability of heavy rainfall has implications for the quantity and quality of regional water resources. Close

• 11. [Article] Use of Water Indices Derived from Landsat OLI Imagery and GIS to Estimate the Hydrologic Connectivity of Wetlands in the Tualatin River National Wildlife Refuge

  This study compared two remote sensing water indices: the Normalized Difference Water Index (NDWI) and the Modified NDWI (MNDWI). Both indices were calculated using publically-available data from the Landsat ...

  Citation × Citation Citation Abstract Copy Title: Use of Water Indices Derived from Landsat OLI Imagery and GIS to Estimate the Hydrologic Connectivity of Wetlands in the Tualatin River National Wildlife Refuge Author: Blackmore, Debra Sue Year: 2016 This study compared two remote sensing water indices: the Normalized Difference Water Index (NDWI) and the Modified NDWI (MNDWI). Both indices were calculated using publically-available data from the Landsat 8 Operational Land Imager (OLI). The research goal was to determine whether the indices are effective in locating open water and measuring surface soil moisture. To demonstrate the application of water indices, analysis was conducted for freshwater wetlands in the Tualatin River Basin in northwestern Oregon to estimate hydrologic connectivity and hydrological permanence between these wetlands and nearby water bodies. Remote sensing techniques have been used to study wetlands in recent decades; however, scientific studies have rarely addressed hydrologic connectivity and hydrologic permanence, in spite of the documented importance of these properties. Research steps were designed to be straightforward for easy repeatability: 1) locate sample sites, 2) predict wetness with water indices, 3) estimate wetness with soil samples from the field, 4) validate the index predictions against the soil samples from the field, and 5) in the demonstration step, estimate hydrologic connectivity and hydrological permanence. Results indicate that both indices predicted the presence of large, open water features with clarity; that dry conditions were predicted by MNDWI with more subtle differentiation; and that NDWI results seem more sensitive to sites with vegetation. Use of this low-cost method to discover patterns of surface moisture in the landscape could directly improve the ability to manage wetland environments. Title: Use of Water Indices Derived from Landsat OLI Imagery and GIS to Estimate the Hydrologic Connectivity of Wetlands in the Tualatin River National Wildlife Refuge Author: Blackmore, Debra Sue Year: 2016 This study compared two remote sensing water indices: the Normalized Difference Water Index (NDWI) and the Modified NDWI (MNDWI). Both indices were calculated using publically-available data from the Landsat 8 Operational Land Imager (OLI). The research goal was to determine whether the indices are effective in locating open water and measuring surface soil moisture. To demonstrate the application of water indices, analysis was conducted for freshwater wetlands in the Tualatin River Basin in northwestern Oregon to estimate hydrologic connectivity and hydrological permanence between these wetlands and nearby water bodies. Remote sensing techniques have been used to study wetlands in recent decades; however, scientific studies have rarely addressed hydrologic connectivity and hydrologic permanence, in spite of the documented importance of these properties. Research steps were designed to be straightforward for easy repeatability: 1) locate sample sites, 2) predict wetness with water indices, 3) estimate wetness with soil samples from the field, 4) validate the index predictions against the soil samples from the field, and 5) in the demonstration step, estimate hydrologic connectivity and hydrological permanence. Results indicate that both indices predicted the presence of large, open water features with clarity; that dry conditions were predicted by MNDWI with more subtle differentiation; and that NDWI results seem more sensitive to sites with vegetation. Use of this low-cost method to discover patterns of surface moisture in the landscape could directly improve the ability to manage wetland environments. Close

• 12. [Article] The stratigraphy of the Scappoose formation, the Astoria formation, and the Columbia River basalt group in northwestern Columbia County, Oregon

  The study area is located in northwestern Columbia County, and covers an area of approximately 70 square kilometers. The purpose of the study was to investigate the possible correlation of the Scappoose ...

  Citation × Citation Citation Abstract Copy Title: The stratigraphy of the Scappoose formation, the Astoria formation, and the Columbia River basalt group in northwestern Columbia County, Oregon Author: Ketrenos, Nancy Tompkins Year: 1986 The study area is located in northwestern Columbia County, and covers an area of approximately 70 square kilometers. The purpose of the study was to investigate the possible correlation of the Scappoose and Astoria Formations and determine their stratigraphic relationship to the Columbia River Basalt Group through mapping, geochemistry and petrography. Title: The stratigraphy of the Scappoose formation, the Astoria formation, and the Columbia River basalt group in northwestern Columbia County, Oregon Author: Ketrenos, Nancy Tompkins Year: 1986 The study area is located in northwestern Columbia County, and covers an area of approximately 70 square kilometers. The purpose of the study was to investigate the possible correlation of the Scappoose and Astoria Formations and determine their stratigraphic relationship to the Columbia River Basalt Group through mapping, geochemistry and petrography. Close

• 13. [Article] Scenario Development and Analysis of Freshwater Ecosystem Services under Land Cover and Climate Change in the Tualatin and Yamhill River Basins, Oregon

  Humans make decisions within ecosystems to enhance their well-being, but choices can lead to unintended consequences. The ecosystem services (ES) approach supports decision-making that considers all environmental ...

  Citation × Citation Citation Abstract Copy Title: Scenario Development and Analysis of Freshwater Ecosystem Services under Land Cover and Climate Change in the Tualatin and Yamhill River Basins, Oregon Author: Hoyer, Robert Wesley Year: 2013 Humans make decisions within ecosystems to enhance their well-being, but choices can lead to unintended consequences. The ecosystem services (ES) approach supports decision-making that considers all environmental goods and services. Many challenges remain in the implementation of the ES approach like how specific ES vary through space and time. We address this research problem using the Tualatin and Yamhill river basins in northwestern Oregon as a study area. Freshwater ES are quantified and mapped with the spatially-explicit ES modeling tool, Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST). In chapter II, we develop a simple urban land cover change modeling approach with selected stakeholder input. The products of this analysis are used in part to answer the question of how the freshwater ES of water yield, nutrient retention, and sediment retention will change in the future, and how their distribution potentially will change? In chapter III, these ES are modeled in InVEST using the land cover scenarios and three downscaled global climate models. The base period is 1981 to 2010 and the future period is 2036 to 2065. The models are calibrated to empirical estimates, and display different sensitivities to inputs. Water yield increases with higher rainfall but decreases with the highest temperature scenario. Nutrient export and retention estimates are positively correlated. In the Tualatin basin, more urban lands generally lead to increases in nutrient exports and retention. The effect is reversed in the Yamhill basin from much larger agricultural exports. Sediment exports and retention increase with higher winter rainfall but are negatively spatially correlated due to topographic effects. Simulation of a landscape scale installation of riparian buffers leads to decreases in exports and increases in retention. The distribution of the provision of freshwater ES remains unchanged throughout the scenarios. With few parameters in each InVEST model, all display a high degree of sensitivity. Parameterization is subject to high uncertainty even with calibrated values. We discuss the assumptions and limitations of InVEST's freshwater models. The spatially explicit nature of InVEST is its main advantage. This work coupled with other analyses in the study area can facilitate the identification of tradeoffs amongst ES leading to better ecosystem management. Title: Scenario Development and Analysis of Freshwater Ecosystem Services under Land Cover and Climate Change in the Tualatin and Yamhill River Basins, Oregon Author: Hoyer, Robert Wesley Year: 2013 Humans make decisions within ecosystems to enhance their well-being, but choices can lead to unintended consequences. The ecosystem services (ES) approach supports decision-making that considers all environmental goods and services. Many challenges remain in the implementation of the ES approach like how specific ES vary through space and time. We address this research problem using the Tualatin and Yamhill river basins in northwestern Oregon as a study area. Freshwater ES are quantified and mapped with the spatially-explicit ES modeling tool, Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST). In chapter II, we develop a simple urban land cover change modeling approach with selected stakeholder input. The products of this analysis are used in part to answer the question of how the freshwater ES of water yield, nutrient retention, and sediment retention will change in the future, and how their distribution potentially will change? In chapter III, these ES are modeled in InVEST using the land cover scenarios and three downscaled global climate models. The base period is 1981 to 2010 and the future period is 2036 to 2065. The models are calibrated to empirical estimates, and display different sensitivities to inputs. Water yield increases with higher rainfall but decreases with the highest temperature scenario. Nutrient export and retention estimates are positively correlated. In the Tualatin basin, more urban lands generally lead to increases in nutrient exports and retention. The effect is reversed in the Yamhill basin from much larger agricultural exports. Sediment exports and retention increase with higher winter rainfall but are negatively spatially correlated due to topographic effects. Simulation of a landscape scale installation of riparian buffers leads to decreases in exports and increases in retention. The distribution of the provision of freshwater ES remains unchanged throughout the scenarios. With few parameters in each InVEST model, all display a high degree of sensitivity. Parameterization is subject to high uncertainty even with calibrated values. We discuss the assumptions and limitations of InVEST's freshwater models. The spatially explicit nature of InVEST is its main advantage. This work coupled with other analyses in the study area can facilitate the identification of tradeoffs amongst ES leading to better ecosystem management. Close

• 14. [Article] Reservoir Evolution Following the Removal of Marmot Dam on the Sandy River, Oregon

  The October 2007 removal of Marmot Dam, a 14.3-m-tall dam on the Sandy River in northwestern Oregon storing approximately 730,000 m3 of impounded sediment, provided an opportunity to study short- and long-term ...

  Citation × Citation Citation Abstract Copy Title: Reservoir Evolution Following the Removal of Marmot Dam on the Sandy River, Oregon Author: Keith, Mackenzie Karli Year: 2012 The October 2007 removal of Marmot Dam, a 14.3-m-tall dam on the Sandy River in northwestern Oregon storing approximately 730,000 m3 of impounded sediment, provided an opportunity to study short- and long-term geomorphic effects of dam removal. Monitoring reservoir morphology during the two years following dam decommissioning yields a timeline of reservoir channel change. Comparison of a pre-dam survey in 1911 with post-removal surveys provides a basis from which to gage the Reservoir Reach evolution in the context of pre-dam conditions. Analyses of time-lapse photography, topographic surveys, and repeat LiDAR data sets provide detailed spatial and temporal documentation of a release of sediment from the reservoir following dam removal. The majority of morphologic changes to the reservoir largely took place during the first few days and weeks following removal. Channel incision and widening, along with gradient changes through the Reservoir Reach, exhibit diminishing changes with time. Channel incision rates of up to 13 m/hr and widening rates of up to 26 m/hr occurred within the first 24 hours following breaching of the coffer dam. Although channel position through the Reservoir Reach has remained relatively stable due to valley confinement, its width increased substantially. The channel reached an average width of 45 m within two weeks of breaching, but then erosion rates slowed and the channel width reached about 70 to 80 m after one and two years, respectively. Diminishing volumes of evacuated sediment were measured over time through quantitative analysis of survey datasets. About 15 percent of the initial impounded sediment was eroded from the Reservoir Reach within 60 hours of breaching; after one and two years, 50 and 58 percent was eroded, respectively. Grain-size analysis of terraces cut into reservoir fill following dam removal show that bed material coarsened over time at fixed elevations and vertically downward as the channel incised. Overall, these findings indicate valley morphology and local in-channel bedrock topography controlled the spatial distribution of sediment within the reservoir reach while variability in river discharge determined the timing of episodic sediment release. Changes within the Reservoir Reach shortly after dam removal and subsequent evolution over the two years following removal are likely attributable to 1) the timing and intensity of flow events, 2) the longitudinal and stratigraphic spatial variations in deposit grain-size distributions initially and over time, and 3) the pre-dam topography and existing valley morphology. Title: Reservoir Evolution Following the Removal of Marmot Dam on the Sandy River, Oregon Author: Keith, Mackenzie Karli Year: 2012 The October 2007 removal of Marmot Dam, a 14.3-m-tall dam on the Sandy River in northwestern Oregon storing approximately 730,000 m3 of impounded sediment, provided an opportunity to study short- and long-term geomorphic effects of dam removal. Monitoring reservoir morphology during the two years following dam decommissioning yields a timeline of reservoir channel change. Comparison of a pre-dam survey in 1911 with post-removal surveys provides a basis from which to gage the Reservoir Reach evolution in the context of pre-dam conditions. Analyses of time-lapse photography, topographic surveys, and repeat LiDAR data sets provide detailed spatial and temporal documentation of a release of sediment from the reservoir following dam removal. The majority of morphologic changes to the reservoir largely took place during the first few days and weeks following removal. Channel incision and widening, along with gradient changes through the Reservoir Reach, exhibit diminishing changes with time. Channel incision rates of up to 13 m/hr and widening rates of up to 26 m/hr occurred within the first 24 hours following breaching of the coffer dam. Although channel position through the Reservoir Reach has remained relatively stable due to valley confinement, its width increased substantially. The channel reached an average width of 45 m within two weeks of breaching, but then erosion rates slowed and the channel width reached about 70 to 80 m after one and two years, respectively. Diminishing volumes of evacuated sediment were measured over time through quantitative analysis of survey datasets. About 15 percent of the initial impounded sediment was eroded from the Reservoir Reach within 60 hours of breaching; after one and two years, 50 and 58 percent was eroded, respectively. Grain-size analysis of terraces cut into reservoir fill following dam removal show that bed material coarsened over time at fixed elevations and vertically downward as the channel incised. Overall, these findings indicate valley morphology and local in-channel bedrock topography controlled the spatial distribution of sediment within the reservoir reach while variability in river discharge determined the timing of episodic sediment release. Changes within the Reservoir Reach shortly after dam removal and subsequent evolution over the two years following removal are likely attributable to 1) the timing and intensity of flow events, 2) the longitudinal and stratigraphic spatial variations in deposit grain-size distributions initially and over time, and 3) the pre-dam topography and existing valley morphology. Close

• 15. [Article] Preliminary investigation for underground storage of pipeline gas in the Bruer and Flora pools, Mist gas field, Columbia County, Oregon

  Northwest Natural Gas Canpany has proposed to convert the Bruer and Flora pools of the Mist Gas Field in west-central Columbia County, Northwestern Oregon, to pipeline gas storage reservoirs. Conversion ...

  Citation × Citation Citation Abstract Copy Title: Preliminary investigation for underground storage of pipeline gas in the Bruer and Flora pools, Mist gas field, Columbia County, Oregon Author: Townley, Paul Joseph Year: 1985 Northwest Natural Gas Canpany has proposed to convert the Bruer and Flora pools of the Mist Gas Field in west-central Columbia County, Northwestern Oregon, to pipeline gas storage reservoirs. Conversion to underground storage of pipeline gas in these depleted gas reservoirs would be the first in the Pacific Northwest. The Bruer and Flora Pools are fault trapped within the Cowlitz Formation. The shales overlying the Cowlitz Formation create a local seal for these gas reservoirs. X-ray diffraction and density log measurements suggest that the clay in these shales is primarily composed of smectite, which provides an excellent caprock seal. The reservoir rock of the Bruer and Flora Pools is the arkosic Cl ark and Wilson Sand. An average weighted grain density for the sand is 2.65 g/cm3. The abundance of potassium feldspar in the sand, hence K40, creates a background gamma radiation for the sand roughly equal to that of the shale, making the sand and shale virtually indistinguishable on the gamma ray log. Bottan Hole Temperatures (BHT), which were recorded on open hole logs, indicate the Bruer Pool is 7°C (20°F) wanner than the Flora Pool, even though the Flora Pool is deeper. This temperature anomaly may be the result of equipment variation. A calibrated temperature survey would remove any discrepancies. A comparison of the thermal gradient determined in a previous study of the Oregon Coast Range and a gradient determined using BHT, suggest that BHT provide a good approximation of formation temperature. Utilizing the formation water analysis determined from four different wells in the Mist Gas Field, average total dissolved solids was found to be 24, 444 mg/l. Of the four analyses, the sample from Well CC#6 R/D2 is considered to be the most representative of the Bruer and Flora fools formation waters. Analysis of the four samples using the Palmer System suggests that the formation water of the Cowlitz Formation is in the early stages of sea water diagenasis. Formation water resistivity (Rw) was determined using a chemical and spontaneous potential analysis. Rw derived using chemical analysis averaged 0.175 ohm-meters and is considered the ITDst precise. Water saturation determined using the Archie saturation equation averaged 47.5% and ranged from 26.4 to 80.0% for the zone 814-836 meters (2670-2742 feet) in CC#10. These results are similar to those determined by the Thermal Time Decay (TDT) log. Title: Preliminary investigation for underground storage of pipeline gas in the Bruer and Flora pools, Mist gas field, Columbia County, Oregon Author: Townley, Paul Joseph Year: 1985 Northwest Natural Gas Canpany has proposed to convert the Bruer and Flora pools of the Mist Gas Field in west-central Columbia County, Northwestern Oregon, to pipeline gas storage reservoirs. Conversion to underground storage of pipeline gas in these depleted gas reservoirs would be the first in the Pacific Northwest. The Bruer and Flora Pools are fault trapped within the Cowlitz Formation. The shales overlying the Cowlitz Formation create a local seal for these gas reservoirs. X-ray diffraction and density log measurements suggest that the clay in these shales is primarily composed of smectite, which provides an excellent caprock seal. The reservoir rock of the Bruer and Flora Pools is the arkosic Cl ark and Wilson Sand. An average weighted grain density for the sand is 2.65 g/cm3. The abundance of potassium feldspar in the sand, hence K40, creates a background gamma radiation for the sand roughly equal to that of the shale, making the sand and shale virtually indistinguishable on the gamma ray log. Bottan Hole Temperatures (BHT), which were recorded on open hole logs, indicate the Bruer Pool is 7°C (20°F) wanner than the Flora Pool, even though the Flora Pool is deeper. This temperature anomaly may be the result of equipment variation. A calibrated temperature survey would remove any discrepancies. A comparison of the thermal gradient determined in a previous study of the Oregon Coast Range and a gradient determined using BHT, suggest that BHT provide a good approximation of formation temperature. Utilizing the formation water analysis determined from four different wells in the Mist Gas Field, average total dissolved solids was found to be 24, 444 mg/l. Of the four analyses, the sample from Well CC#6 R/D2 is considered to be the most representative of the Bruer and Flora fools formation waters. Analysis of the four samples using the Palmer System suggests that the formation water of the Cowlitz Formation is in the early stages of sea water diagenasis. Formation water resistivity (Rw) was determined using a chemical and spontaneous potential analysis. Rw derived using chemical analysis averaged 0.175 ohm-meters and is considered the ITDst precise. Water saturation determined using the Archie saturation equation averaged 47.5% and ranged from 26.4 to 80.0% for the zone 814-836 meters (2670-2742 feet) in CC#10. These results are similar to those determined by the Thermal Time Decay (TDT) log. Close

• 16. [Article] Bioenergy Harvest, Climate Change, and Forest Carbon in the Oregon Coast Range

  Forests provide important ecological, economic and social services, and recent interest has emerged in the potential for using residue from timber harvest as a source of renewable woody bioenergy. The ...

  Citation × Citation Citation Abstract Copy Title: Bioenergy Harvest, Climate Change, and Forest Carbon in the Oregon Coast Range Author: Creutzburg, Megan K., Scheller, Robert M., Lucash, Melissa S., Evers, Louisa B., LeDuc, Stephen D., Johnson, Mark G. Year: 2016 Forests provide important ecological, economic and social services, and recent interest has emerged in the potential for using residue from timber harvest as a source of renewable woody bioenergy. The long-term consequences of such intensive harvest are unclear, particularly as forests face novel climatic conditions over the next century. We used a simulation model to project the long-term effects of management and climate change on above- and below ground carbon storage in a watershed in northwestern Oregon. The multi-ownership watershed has a diverse range of current management practices, including little-to-no harvesting on federal lands, short-rotation clear-cutting on industrial land, and a mix of practices on private non-industrial land. We simulated multiple management scenarios, varying the rate and intensity of harvest, combined with projections of climate change. Our simulations project a wide range of total ecosystem carbon storage with varying harvest rate, ranging from a 45% increase to a 16% decrease compared to current levels. Increasing the intensity of harvest for bioenergy caused an additional 2-3% decrease in ecosystem carbon relative to conventional harvest practices. Soil carbon was relatively insensitive to harvest rotation and intensity, and accumulated slowly regardless of harvest regime. Climate change reduced carbon accumulation in soil and detrital pools due to increasing heterotrophic respiration, and had variable effects on total ecosystem carbon, ranging from a 5% decrease to a 2% increase depending on management scenario. Overall, we conclude that current levels of ecosystem carbon storage are maintained in part due to substantial portions of the landscape (federal and some private lands) remaining unharvested or lightly managed. Increasing the intensity of harvest for bioenergy on currently harvested land, however, led to a small reduction in the ability of forests to store carbon. Climate change is unlikely to substantially alter carbon storage in these forests, absent shifts in disturbance regimes. Title: Bioenergy Harvest, Climate Change, and Forest Carbon in the Oregon Coast Range Author: Creutzburg, Megan K., Scheller, Robert M., Lucash, Melissa S., Evers, Louisa B., LeDuc, Stephen D., Johnson, Mark G. Year: 2016 Forests provide important ecological, economic and social services, and recent interest has emerged in the potential for using residue from timber harvest as a source of renewable woody bioenergy. The long-term consequences of such intensive harvest are unclear, particularly as forests face novel climatic conditions over the next century. We used a simulation model to project the long-term effects of management and climate change on above- and below ground carbon storage in a watershed in northwestern Oregon. The multi-ownership watershed has a diverse range of current management practices, including little-to-no harvesting on federal lands, short-rotation clear-cutting on industrial land, and a mix of practices on private non-industrial land. We simulated multiple management scenarios, varying the rate and intensity of harvest, combined with projections of climate change. Our simulations project a wide range of total ecosystem carbon storage with varying harvest rate, ranging from a 45% increase to a 16% decrease compared to current levels. Increasing the intensity of harvest for bioenergy caused an additional 2-3% decrease in ecosystem carbon relative to conventional harvest practices. Soil carbon was relatively insensitive to harvest rotation and intensity, and accumulated slowly regardless of harvest regime. Climate change reduced carbon accumulation in soil and detrital pools due to increasing heterotrophic respiration, and had variable effects on total ecosystem carbon, ranging from a 5% decrease to a 2% increase depending on management scenario. Overall, we conclude that current levels of ecosystem carbon storage are maintained in part due to substantial portions of the landscape (federal and some private lands) remaining unharvested or lightly managed. Increasing the intensity of harvest for bioenergy on currently harvested land, however, led to a small reduction in the ability of forests to store carbon. Climate change is unlikely to substantially alter carbon storage in these forests, absent shifts in disturbance regimes. Close

• 17. [Article] Long-term Responses of Phalaris arundinacea and Columbia River Bottomland Vegetation to Managed Flooding

  I sought to determine the effect of managed flooding on Phalaris arundinacea L. and other plant species distributions in a large wetland complex, Smith and Bybee Wetlands (SBW), in northwestern Oregon. ...

  Citation × Citation Citation Abstract Copy Title: Long-term Responses of Phalaris arundinacea and Columbia River Bottomland Vegetation to Managed Flooding Author: Farrelly, Tina Schantz Year: 2012 I sought to determine the effect of managed flooding on Phalaris arundinacea L. and other plant species distributions in a large wetland complex, Smith and Bybee Wetlands (SBW), in northwestern Oregon. Altered hydrology has reduced historically high spring flow and prematurely initiated the historic summer drying period at SBW. This alteration has increased the coverage of invasive plants (e.g., P. arundinacea) causing a decrease in native plant cover and thus degrading ecological functions. SBW managers installed a water control structure (WCS) between SBW and the Columbia Slough/River system to impound winter rainfall and thus approximate the ecological benefits that natural flooding provided as well as reduce the abundance of P. arundinacea. Prior researchers conducted intensive vegetation and hydrological monitoring in 2003 (during the season immediately before WCS installation) and 2004. I conducted similar analysis in the fifth and sixth years, 2008 and 2009, following establishment of the WCS. Both study years, I determined percent cover of all vegetation on transects established in 2003. The results, including 2004, as well as 2008 and 2009 showed a reduced cover of P. arundinacea in areas experiencing at least 0.6 meters of inundation and an increased cover of native plant communities when compared to the 2003 baseline data. Native Carex aperta Boott. cover increased 7-fold from 0.3% to 2.3%; Polygonum species cover increased from 20.0% to 52.6%; and Salix lucida Muhl. ssp. lasiandra (Benth.) E. Murray cover increased from 10.9% to 15.5% cover. P. arundinacea declined by over one-third from 44.4% to 28.1% cover following water management. Since hydrology management began, the native Polygonum species community replaced P. arundinacea as the dominant species in the emergent zone. The results of this study refined the suggested depth of inundation needed to reduce P. arundinacea cover in such lake-wetland complexes as SBW from 0.85 meters (based on 2004 study results) to 0.6 meters. Shannon Diversity decreased following water management. The findings of this study demonstrated that water management can enhance native bottomland communities, especially those comprised of obligate wetland species, and reduce P. arundinacea cover in areas experiencing at least 0.6 meters of inundation. Title: Long-term Responses of Phalaris arundinacea and Columbia River Bottomland Vegetation to Managed Flooding Author: Farrelly, Tina Schantz Year: 2012 I sought to determine the effect of managed flooding on Phalaris arundinacea L. and other plant species distributions in a large wetland complex, Smith and Bybee Wetlands (SBW), in northwestern Oregon. Altered hydrology has reduced historically high spring flow and prematurely initiated the historic summer drying period at SBW. This alteration has increased the coverage of invasive plants (e.g., P. arundinacea) causing a decrease in native plant cover and thus degrading ecological functions. SBW managers installed a water control structure (WCS) between SBW and the Columbia Slough/River system to impound winter rainfall and thus approximate the ecological benefits that natural flooding provided as well as reduce the abundance of P. arundinacea. Prior researchers conducted intensive vegetation and hydrological monitoring in 2003 (during the season immediately before WCS installation) and 2004. I conducted similar analysis in the fifth and sixth years, 2008 and 2009, following establishment of the WCS. Both study years, I determined percent cover of all vegetation on transects established in 2003. The results, including 2004, as well as 2008 and 2009 showed a reduced cover of P. arundinacea in areas experiencing at least 0.6 meters of inundation and an increased cover of native plant communities when compared to the 2003 baseline data. Native Carex aperta Boott. cover increased 7-fold from 0.3% to 2.3%; Polygonum species cover increased from 20.0% to 52.6%; and Salix lucida Muhl. ssp. lasiandra (Benth.) E. Murray cover increased from 10.9% to 15.5% cover. P. arundinacea declined by over one-third from 44.4% to 28.1% cover following water management. Since hydrology management began, the native Polygonum species community replaced P. arundinacea as the dominant species in the emergent zone. The results of this study refined the suggested depth of inundation needed to reduce P. arundinacea cover in such lake-wetland complexes as SBW from 0.85 meters (based on 2004 study results) to 0.6 meters. Shannon Diversity decreased following water management. The findings of this study demonstrated that water management can enhance native bottomland communities, especially those comprised of obligate wetland species, and reduce P. arundinacea cover in areas experiencing at least 0.6 meters of inundation. Close

• 18. [Article] Field Mapping Investigation and Geochemical Analysis of Volcanic Units within the Dinner Creek Tuff Eruptive Center, Malheur County, Eastern Oregon

  The Dinner Creek Tuff is a mid-Miocene rhyolitic to dacitic ignimbrite, consisting of four cooling units with 40Ar/39Ar ages 16--15 Ma. Previous geologists have suspected that the source of the tuff is ...

  Citation × Citation Citation Abstract Copy Title: Field Mapping Investigation and Geochemical Analysis of Volcanic Units within the Dinner Creek Tuff Eruptive Center, Malheur County, Eastern Oregon Author: Cruz, Matthew Year: 2017 The Dinner Creek Tuff is a mid-Miocene rhyolitic to dacitic ignimbrite, consisting of four cooling units with 40Ar/39Ar ages 16--15 Ma. Previous geologists have suspected that the source of the tuff is located in northwestern Malheur County, eastern Oregon. This broad area is called the Dinner Creek Tuff Eruptive Center. This thesis summarizes field work, XRF/ICP-MS geochemistry, thin section petrography, and SEM feldspar analysis from the summers of 2015 and 2016. The main purpose of this study is to identify sources for the Dinner Creek Tuff units within the Dinner Creek Tuff Eruptive Center. The secondary purpose is to map lave flows that pre-date and post-date the Dinner Creek Tuff, and correlate them with regionally extensive volcanic units. Two volcanic centers related to the Dinner Creek Tuff were identified. The southern volcanic center, centered at Castle Rock, is a caldera and source of the Dinner Creek Tuff unit 1 (DIT1). Rheomorphic, densely welded DIT1 is over 300 m thick along the east side of Castle Rock. The northwestern margin of the caldera has been uplifted along faults, showing vertically foliated tuff dikes and associated mega-breccia deposits. Up to 200 m of incipiently welded tuffs, and fluvial volcanoclastic sediments were deposited on the caldera floor, which has been uplifted due to resurgence and regional extension, creating the complex structural relationships between the volcanic units. The northern volcanic center is located at Ironside Mountain, where densely welded rheomorphic Dinner Creek Tuff unit 2 (DIT2) is exposed in outcrops over 600 m thick. The top of the DIT2 consists of glassy, moderately welded tuff. Sources for the DIT2 are tuff dikes along the south and western flanks of Ironside Mountain. The thick deposits of DIT2 at Ironside Mountain indicate that the mountain is an uplifted caldera, herein named the Ironside Mountain caldera. Uplift may have been due to resurgence, but it is most likely due to normal faulting along the Border Fault, a major regional normal fault that strikes across the northern margin of the caldera. Pre-Dinner Creek Tuff lava flows occur throughout the study area, and can be correlated with the Strawberry Volcanics and the Basalt of Malheur Gorge. A distinct lava flow, herein called the Ring Butte trachy-basalt occurs within the center of the study area, and is distinct from regional lava flows. Following the eruptions of the Dinner Creek Tuff units 1 & 2, aphyric basaltic-andesite and icelandite intrude into, and overlie the intra-caldera tuffs and caldera floor sediments at both calderas. These aphyric lavas are similar in appearance and stratigraphic position with the regionally extensive Hunter Creek basalt. Porphyritic olivine basalt overlies the aphyric Hunter Creek basalt at the Castle Rock caldera. This porphyritic lava is similar in appearance and major/trace element geochemistry to the regional Tim's Peak basalt. Title: Field Mapping Investigation and Geochemical Analysis of Volcanic Units within the Dinner Creek Tuff Eruptive Center, Malheur County, Eastern Oregon Author: Cruz, Matthew Year: 2017 The Dinner Creek Tuff is a mid-Miocene rhyolitic to dacitic ignimbrite, consisting of four cooling units with 40Ar/39Ar ages 16--15 Ma. Previous geologists have suspected that the source of the tuff is located in northwestern Malheur County, eastern Oregon. This broad area is called the Dinner Creek Tuff Eruptive Center. This thesis summarizes field work, XRF/ICP-MS geochemistry, thin section petrography, and SEM feldspar analysis from the summers of 2015 and 2016. The main purpose of this study is to identify sources for the Dinner Creek Tuff units within the Dinner Creek Tuff Eruptive Center. The secondary purpose is to map lave flows that pre-date and post-date the Dinner Creek Tuff, and correlate them with regionally extensive volcanic units. Two volcanic centers related to the Dinner Creek Tuff were identified. The southern volcanic center, centered at Castle Rock, is a caldera and source of the Dinner Creek Tuff unit 1 (DIT1). Rheomorphic, densely welded DIT1 is over 300 m thick along the east side of Castle Rock. The northwestern margin of the caldera has been uplifted along faults, showing vertically foliated tuff dikes and associated mega-breccia deposits. Up to 200 m of incipiently welded tuffs, and fluvial volcanoclastic sediments were deposited on the caldera floor, which has been uplifted due to resurgence and regional extension, creating the complex structural relationships between the volcanic units. The northern volcanic center is located at Ironside Mountain, where densely welded rheomorphic Dinner Creek Tuff unit 2 (DIT2) is exposed in outcrops over 600 m thick. The top of the DIT2 consists of glassy, moderately welded tuff. Sources for the DIT2 are tuff dikes along the south and western flanks of Ironside Mountain. The thick deposits of DIT2 at Ironside Mountain indicate that the mountain is an uplifted caldera, herein named the Ironside Mountain caldera. Uplift may have been due to resurgence, but it is most likely due to normal faulting along the Border Fault, a major regional normal fault that strikes across the northern margin of the caldera. Pre-Dinner Creek Tuff lava flows occur throughout the study area, and can be correlated with the Strawberry Volcanics and the Basalt of Malheur Gorge. A distinct lava flow, herein called the Ring Butte trachy-basalt occurs within the center of the study area, and is distinct from regional lava flows. Following the eruptions of the Dinner Creek Tuff units 1 & 2, aphyric basaltic-andesite and icelandite intrude into, and overlie the intra-caldera tuffs and caldera floor sediments at both calderas. These aphyric lavas are similar in appearance and stratigraphic position with the regionally extensive Hunter Creek basalt. Porphyritic olivine basalt overlies the aphyric Hunter Creek basalt at the Castle Rock caldera. This porphyritic lava is similar in appearance and major/trace element geochemistry to the regional Tim's Peak basalt. Close

• 19. [Article] A comparative study of the Northwestern Syntax Screening Test data

  The purpose of this study was to compare NSST data (Lee, 1969, 1971) with data obtained in Portland, Oregon for children 4.0-4.11 years of age. The questions this study sought to answer were: 1) Is there ...

  Citation × Citation Citation Abstract Copy Title: A comparative study of the Northwestern Syntax Screening Test data Author: Moore, Sharon Ann Year: 1985 The purpose of this study was to compare NSST data (Lee, 1969, 1971) with data obtained in Portland, Oregon for children 4.0-4.11 years of age. The questions this study sought to answer were: 1) Is there a significant difference between the expressive and receptive scores obtained by Lee, (1969, 1971) and the scores obtained in Portland, Oregon? 2) What are the means, standard deviations and percentiles of the NSST scores of a select group of four-year-old children in Portland, Oregon? Title: A comparative study of the Northwestern Syntax Screening Test data Author: Moore, Sharon Ann Year: 1985 The purpose of this study was to compare NSST data (Lee, 1969, 1971) with data obtained in Portland, Oregon for children 4.0-4.11 years of age. The questions this study sought to answer were: 1) Is there a significant difference between the expressive and receptive scores obtained by Lee, (1969, 1971) and the scores obtained in Portland, Oregon? 2) What are the means, standard deviations and percentiles of the NSST scores of a select group of four-year-old children in Portland, Oregon? Close

• 20. [Article] A population study of three iris (iridaceae) species native to the Siskiyou Mountains in southwestern Oregon and adjacent California

  The series Californicae is a natural grouping of Iris species native to Oregon, Washington and California. Natural and experimental hybridization is characteristic of the series which has led to confusing ...

  Citation × Citation Citation Abstract Copy Title: A population study of three iris (iridaceae) species native to the Siskiyou Mountains in southwestern Oregon and adjacent California Author: Wilson, Carol Anne Year: 1983 The series Californicae is a natural grouping of Iris species native to Oregon, Washington and California. Natural and experimental hybridization is characteristic of the series which has led to confusing taxonomies for some species. Populations of species belonging to this series and found on the northwestern slopes of the Siskiyou Mountains cf southwestern Oregon and adjacent California were investigated. Methods used were numerical classification techniques for morphological characters including both discriminant and K-means cluster analyses and a chemotaxonomi c analysis of flavonoid pigments using thin layer chromatography. Title: A population study of three iris (iridaceae) species native to the Siskiyou Mountains in southwestern Oregon and adjacent California Author: Wilson, Carol Anne Year: 1983 The series Californicae is a natural grouping of Iris species native to Oregon, Washington and California. Natural and experimental hybridization is characteristic of the series which has led to confusing taxonomies for some species. Populations of species belonging to this series and found on the northwestern slopes of the Siskiyou Mountains cf southwestern Oregon and adjacent California were investigated. Methods used were numerical classification techniques for morphological characters including both discriminant and K-means cluster analyses and a chemotaxonomi c analysis of flavonoid pigments using thin layer chromatography. Close

• 21. [Article] Oregon Natural Areas Plan

  The rich diversity of ecosystems and native plants and animals is one of Oregon's most distinctive and valued qualities. Our state contains rain forests, dry forests, oak woodlands, alpine meadows, prairies, ...

  Citation × Citation Citation Abstract Copy Title: Oregon Natural Areas Plan Author: Oregon Natural Heritage Advisory Council Year: 2010 The rich diversity of ecosystems and native plants and animals is one of Oregon's most distinctive and valued qualities. Our state contains rain forests, dry forests, oak woodlands, alpine meadows, prairies, deserts, marshes, estuaries, dunes, rocky headlands, lakes and streams. There are a number of reasons it is so diverse. First are the extremes of climate, with rainfall ranging from over 200 inches a year along Oregon’s north coast, to less than 7 inches a year in the Alvord Desert, and temperatures from the very mild banana belt along the coast near the California border to the extremes of the high alpine areas of the Wallowa Mountains. Secondly, Oregon is diverse geographically and geologically, having ancient serpentine landscapes in the Siskiyou Mountains and recent volcanics in the Cascades and the deepest gorge in North America at Hells Canyon. Lastly, Oregon is a floristic crossroads, with arctic boreal species finding their southern limit, Rocky Mountain species common in northeastern Oregon, Great Basin species in southeastern Oregon, and California coastal and Sierra species in the southwest, all mixing with native northwestern taxa to create a wide array of habitats. Title: Oregon Natural Areas Plan Author: Oregon Natural Heritage Advisory Council Year: 2010 The rich diversity of ecosystems and native plants and animals is one of Oregon's most distinctive and valued qualities. Our state contains rain forests, dry forests, oak woodlands, alpine meadows, prairies, deserts, marshes, estuaries, dunes, rocky headlands, lakes and streams. There are a number of reasons it is so diverse. First are the extremes of climate, with rainfall ranging from over 200 inches a year along Oregon’s north coast, to less than 7 inches a year in the Alvord Desert, and temperatures from the very mild banana belt along the coast near the California border to the extremes of the high alpine areas of the Wallowa Mountains. Secondly, Oregon is diverse geographically and geologically, having ancient serpentine landscapes in the Siskiyou Mountains and recent volcanics in the Cascades and the deepest gorge in North America at Hells Canyon. Lastly, Oregon is a floristic crossroads, with arctic boreal species finding their southern limit, Rocky Mountain species common in northeastern Oregon, Great Basin species in southeastern Oregon, and California coastal and Sierra species in the southwest, all mixing with native northwestern taxa to create a wide array of habitats. Close

• 22. [Article] The Burden of Oregon History: The Historian as Prophet

  In the latter part of his public career, after a lifetime of studying and thinking about the region and its people, Dodds began to write about “the tragedy of the lack of tragedy” in the lives of Pacific ...

  Citation × Citation Citation Abstract Copy Title: The Burden of Oregon History: The Historian as Prophet Author: Rosenberg, John P. Year: 2005 In the latter part of his public career, after a lifetime of studying and thinking about the region and its people, Dodds began to write about “the tragedy of the lack of tragedy” in the lives of Pacific Northwesterners. Life had been relatively easy and perhaps “too successful” for the region’s citizens, “especially if one were a Caucasian,” wrote Gordon Dodds in the epilogue to his 1986 regional history, The American Northwest: A History of Oregon and Washington. Pacific Northwesterners had mastered their few difficulties with relative ease and their undemanding past may have left them unprepared for the adversities that lay ahead. Whatever vague foreboding Dodds may have sensed when he wrote those words in the mid-1980s, the adversity he alluded to was not long in appearing. With the passage of the property tax limitation Measure 5 in Oregon in 1991, whatever fragile regional consensus existed regarding the public funding of education and social welfare programs came crashing down. The passage some 15 years later of Measure 37, which essentially dismantled Oregon’s nationally acclaimed land-use planning system, completed the apparent sea change in regional self-understanding. Whatever reputation Oregon had previously enjoyed as a bastion of environmental commitment and liberal sentiment was now defunct. A brave new world of libertarian values and minimal government intrusion (or support) was ready to greet any new arrivals. While the changes in political sentiment in Oregon reflected the rise of conservative values nationally, they seemed especially pronounced here given the state’s prior reputation. All this, of course, begs the question of whether or not, given these apparently great changes in Oregonians’ social and political self-understanding, the past in any sense could have served as prelude to someone who wanted to trace a vague outline of the future before it was thrust upon us in its present form. Were the seeds of Oregon’s current dilemma buried in its past? Could an alert and curious historian who knew where to look have predicted the current state of affairs, in which every session of the legislature, for example, pits proponents of public education against supporters of social welfare programs for an every-shrinking revenue pie? What happened to the Oregon that, despite its eccentricities and contradictions, many of us knew and loved before 1991? And was its rapid demise predictable? Title: The Burden of Oregon History: The Historian as Prophet Author: Rosenberg, John P. Year: 2005 In the latter part of his public career, after a lifetime of studying and thinking about the region and its people, Dodds began to write about “the tragedy of the lack of tragedy” in the lives of Pacific Northwesterners. Life had been relatively easy and perhaps “too successful” for the region’s citizens, “especially if one were a Caucasian,” wrote Gordon Dodds in the epilogue to his 1986 regional history, The American Northwest: A History of Oregon and Washington. Pacific Northwesterners had mastered their few difficulties with relative ease and their undemanding past may have left them unprepared for the adversities that lay ahead. Whatever vague foreboding Dodds may have sensed when he wrote those words in the mid-1980s, the adversity he alluded to was not long in appearing. With the passage of the property tax limitation Measure 5 in Oregon in 1991, whatever fragile regional consensus existed regarding the public funding of education and social welfare programs came crashing down. The passage some 15 years later of Measure 37, which essentially dismantled Oregon’s nationally acclaimed land-use planning system, completed the apparent sea change in regional self-understanding. Whatever reputation Oregon had previously enjoyed as a bastion of environmental commitment and liberal sentiment was now defunct. A brave new world of libertarian values and minimal government intrusion (or support) was ready to greet any new arrivals. While the changes in political sentiment in Oregon reflected the rise of conservative values nationally, they seemed especially pronounced here given the state’s prior reputation. All this, of course, begs the question of whether or not, given these apparently great changes in Oregonians’ social and political self-understanding, the past in any sense could have served as prelude to someone who wanted to trace a vague outline of the future before it was thrust upon us in its present form. Were the seeds of Oregon’s current dilemma buried in its past? Could an alert and curious historian who knew where to look have predicted the current state of affairs, in which every session of the legislature, for example, pits proponents of public education against supporters of social welfare programs for an every-shrinking revenue pie? What happened to the Oregon that, despite its eccentricities and contradictions, many of us knew and loved before 1991? And was its rapid demise predictable? Close

• 23. [Article] Biostratigraphy of the type Weberg Member, Snowshoe Formation, Grant County, Oregon

  Thirty three species of ammonites are recorded from the composite type section of the Weberg Member of the Snowshoe Formation in the Suplee area, Grant County, Oregon. Holcophylloceras burkei, Euhoploceras ...

  Citation × Citation Citation Abstract Copy Title: Biostratigraphy of the type Weberg Member, Snowshoe Formation, Grant County, Oregon Author: Taylor, David G. Year: 1977 Thirty three species of ammonites are recorded from the composite type section of the Weberg Member of the Snowshoe Formation in the Suplee area, Grant County, Oregon. Holcophylloceras burkei, Euhoploceras westi, E. tubereulosum and Strigoceras taylori are described as new, while four new species belonging to the genera Sonninia [?], Bradfordia, Pseudotoites and Witchellia are not formally named. Three ammonite zonules characterize the ammonite sequence of the type Weberg composite section. The sequence correlates with parts of the standard lower and middle Bajocian (Jurassic) of northwestern Europe. In addition, four associations (paleo-communities) of benthic mega invertebrates, the Gervillia, Protocardia, Isocyprina and Bositra buahii associations are delineated. The type Weberg composite section is a record of a local marine transgression westward onto an island system. The section also represents sedimentation over an irregular pre-Snowshoe topographic high, and indicates a progressive change from proximal to distal source of pre-Snowshoe sediments, from high to low energy conditions, and perhaps a slight deepening of the ocean bottom. Ammonites are rare in the lower division of the Weberg Member, locally present in fine sandy limestones of the lower part of the upper division, abundant and most diverse in silt-rich, clay-poor limestones of the upper part of the upper division, and locally abundant in mudstones of the Warm Springs Member. Recurrent associations of certain ammonite species, strong correlation of the associations with lithofacies and biofacies, and pervasive faunal differences of ammonites between facies indicate in general that the distributional patterns of the ammonites reflect spatial life-habitats. The spotty yet widespread geographic occurrence of several ammonite species suggest they had undergone extensive planktic dispersal, thus ocean currents probably played an important role in their distributional patterns. Title: Biostratigraphy of the type Weberg Member, Snowshoe Formation, Grant County, Oregon Author: Taylor, David G. Year: 1977 Thirty three species of ammonites are recorded from the composite type section of the Weberg Member of the Snowshoe Formation in the Suplee area, Grant County, Oregon. Holcophylloceras burkei, Euhoploceras westi, E. tubereulosum and Strigoceras taylori are described as new, while four new species belonging to the genera Sonninia [?], Bradfordia, Pseudotoites and Witchellia are not formally named. Three ammonite zonules characterize the ammonite sequence of the type Weberg composite section. The sequence correlates with parts of the standard lower and middle Bajocian (Jurassic) of northwestern Europe. In addition, four associations (paleo-communities) of benthic mega invertebrates, the Gervillia, Protocardia, Isocyprina and Bositra buahii associations are delineated. The type Weberg composite section is a record of a local marine transgression westward onto an island system. The section also represents sedimentation over an irregular pre-Snowshoe topographic high, and indicates a progressive change from proximal to distal source of pre-Snowshoe sediments, from high to low energy conditions, and perhaps a slight deepening of the ocean bottom. Ammonites are rare in the lower division of the Weberg Member, locally present in fine sandy limestones of the lower part of the upper division, abundant and most diverse in silt-rich, clay-poor limestones of the upper part of the upper division, and locally abundant in mudstones of the Warm Springs Member. Recurrent associations of certain ammonite species, strong correlation of the associations with lithofacies and biofacies, and pervasive faunal differences of ammonites between facies indicate in general that the distributional patterns of the ammonites reflect spatial life-habitats. The spotty yet widespread geographic occurrence of several ammonite species suggest they had undergone extensive planktic dispersal, thus ocean currents probably played an important role in their distributional patterns. Close

• 24. [Article] Hydrogeologic Investigation of the Klamath Marsh, Klamath County, Oregon

  Klamath Marsh is a wetland complex that lies in the rain shadow of the Cascade Range in the Williamson River sub-basin of the Klamath Basin. The marsh lies directly east of Crater Lake in an area inundated ...

  Citation × Citation Citation Abstract Copy Title: Hydrogeologic Investigation of the Klamath Marsh, Klamath County, Oregon Author: Melady, Jason Michael Year: 2002 Klamath Marsh is a wetland complex that lies in the rain shadow of the Cascade Range in the Williamson River sub-basin of the Klamath Basin. The marsh lies directly east of Crater Lake in an area inundated by pyroclastic-flow and -fall deposits from the Holocene eruptions of Mount Mazama. The physical characteristics of rocks of Pleistocene versus Pliocene age combined with NNW -striking fault systems divide the Williamson River basin into two distinct hydrogeologic regimes. The northwestern regime includes the east slope of the Cascades and consists of at least 150 m of interbedded sand, gravel, and stacks (15 to 45 m) of thin (3-5 m) and vesiculated basalt lava flows. Mean annual precipitation ranges from 150 cm near the crest of the Cascades to 50 cm near Klamath Marsh. Moderate to high yield (100 to 4000 gpm) water wells, springs and flowing wells suggest high permeability and ground water potential. The southeastern regime is underlain by Pliocene pyroclastic flows (∼ 40 m) and lava flows (>30 m). Mean annual precipitation ranges from 70 cm in the highlands to 50 cm in the lowlands. Low-yield (20-100 gpm) water wells and perched unconfined aquifers in Holocene pumice deposits suggest low permeability and low ground water potential in areas underlain by the pyroclastic flows. Volumetric analysis of inflows and outflows in Klamath Marsh for 2000 indicates approximately 86% of inflow is from groundwater and 14% from surface water, with nearly 200 x 10⁶ m³ of water removed by evapotranspiration Title: Hydrogeologic Investigation of the Klamath Marsh, Klamath County, Oregon Author: Melady, Jason Michael Year: 2002 Klamath Marsh is a wetland complex that lies in the rain shadow of the Cascade Range in the Williamson River sub-basin of the Klamath Basin. The marsh lies directly east of Crater Lake in an area inundated by pyroclastic-flow and -fall deposits from the Holocene eruptions of Mount Mazama. The physical characteristics of rocks of Pleistocene versus Pliocene age combined with NNW -striking fault systems divide the Williamson River basin into two distinct hydrogeologic regimes. The northwestern regime includes the east slope of the Cascades and consists of at least 150 m of interbedded sand, gravel, and stacks (15 to 45 m) of thin (3-5 m) and vesiculated basalt lava flows. Mean annual precipitation ranges from 150 cm near the crest of the Cascades to 50 cm near Klamath Marsh. Moderate to high yield (100 to 4000 gpm) water wells, springs and flowing wells suggest high permeability and ground water potential. The southeastern regime is underlain by Pliocene pyroclastic flows (∼ 40 m) and lava flows (>30 m). Mean annual precipitation ranges from 70 cm in the highlands to 50 cm in the lowlands. Low-yield (20-100 gpm) water wells and perched unconfined aquifers in Holocene pumice deposits suggest low permeability and low ground water potential in areas underlain by the pyroclastic flows. Volumetric analysis of inflows and outflows in Klamath Marsh for 2000 indicates approximately 86% of inflow is from groundwater and 14% from surface water, with nearly 200 x 10⁶ m³ of water removed by evapotranspiration Close

• 25. [Article] Phylogeography of Two Species of the Genus Apochthonius Chamberlin, 1929, in the Pacific Northwest (Arachnida, Pseudoscorpiones)

  I used mitochondrial COI sequence data from forty one individuals to investigate phylogenetic relationships among populations of two morphologically similar species of the pseudoscorpion genus Apochthonius, ...

  Citation × Citation Citation Abstract Copy Title: Phylogeography of Two Species of the Genus Apochthonius Chamberlin, 1929, in the Pacific Northwest (Arachnida, Pseudoscorpiones) Author: Welch, Brandi Lynn Year: 2016 I used mitochondrial COI sequence data from forty one individuals to investigate phylogenetic relationships among populations of two morphologically similar species of the pseudoscorpion genus Apochthonius, A. minimus and A. occidentalis, in western Washington, Oregon, and northern California. My goal was to assess whether genetic structure in the two species was congruent with geography. Many plant and animal species in the Pacific Northwestern United States have shown patterns of genetic differentiation that follow both north-south and east-west trends, indicating that geologic and climatic events in the past separated populations to the extent that they became genetically differentiated. A distinct geographic pattern emerged within A. occidentalis, with at least one northern and two southern populations. A clade containing all A. minimus sequences was recovered. However, this clade falls within the larger clade of A. occidentalis, rendering A. occidentalis paraphyletic. Furthermore, the A. minimus sequences showed north-south geographic structuring within the clade. Population genetic analyses were performed based on geographic location within the Pacific Northwest. I found high genetic differentiation coupled with low gene flow between most populations, with the exception of the Portland and North Coast Range populations. These data suggest the presence of more than two species of Apochthonius in the Pacific Northwest. Title: Phylogeography of Two Species of the Genus Apochthonius Chamberlin, 1929, in the Pacific Northwest (Arachnida, Pseudoscorpiones) Author: Welch, Brandi Lynn Year: 2016 I used mitochondrial COI sequence data from forty one individuals to investigate phylogenetic relationships among populations of two morphologically similar species of the pseudoscorpion genus Apochthonius, A. minimus and A. occidentalis, in western Washington, Oregon, and northern California. My goal was to assess whether genetic structure in the two species was congruent with geography. Many plant and animal species in the Pacific Northwestern United States have shown patterns of genetic differentiation that follow both north-south and east-west trends, indicating that geologic and climatic events in the past separated populations to the extent that they became genetically differentiated. A distinct geographic pattern emerged within A. occidentalis, with at least one northern and two southern populations. A clade containing all A. minimus sequences was recovered. However, this clade falls within the larger clade of A. occidentalis, rendering A. occidentalis paraphyletic. Furthermore, the A. minimus sequences showed north-south geographic structuring within the clade. Population genetic analyses were performed based on geographic location within the Pacific Northwest. I found high genetic differentiation coupled with low gene flow between most populations, with the exception of the Portland and North Coast Range populations. These data suggest the presence of more than two species of Apochthonius in the Pacific Northwest. Close

• 26. [Article] Dreissenid Mussel Research Priorities Workshop

  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 ...

  Citation × Citation Citation Abstract Copy Title: Dreissenid Mussel Research Priorities Workshop Author: Sytsma, Mark D., Phillips, Stephen, Counihan, Timothy D. Year: 2015 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 Priorities Workshop funded by the Great Northern Landscape Conservation Cooperative. The purpose of the workshop was to review dreissenid research priorities in the 2010 Quagga-Zebra Mussel Action Plan for Western U.S. Waters, reassess those priorities, incorporate new information and emerging trends, and develop priorities to strategically focus research efforts on zebra and quagga mussels in the Pacific Northwest and ensure that future research is focused on the highest priorities. It is important to note that there is some repetition among dreissenid research priority categories (e.g., prevention, detection, control, monitoring, and biology). Workshop participants with research experience in dreissenid mussel biology and management were identified by a literature review. State and federal agency managers were also invited to the workshop to ensure relevancy and practicality of the work­shop outcomes. A total of 28 experts (see sidebar) in mussel biology, ecology, and management attended the workshop. Title: Dreissenid Mussel Research Priorities Workshop Author: Sytsma, Mark D., Phillips, Stephen, Counihan, Timothy D. Year: 2015 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 Priorities Workshop funded by the Great Northern Landscape Conservation Cooperative. The purpose of the workshop was to review dreissenid research priorities in the 2010 Quagga-Zebra Mussel Action Plan for Western U.S. Waters, reassess those priorities, incorporate new information and emerging trends, and develop priorities to strategically focus research efforts on zebra and quagga mussels in the Pacific Northwest and ensure that future research is focused on the highest priorities. It is important to note that there is some repetition among dreissenid research priority categories (e.g., prevention, detection, control, monitoring, and biology). Workshop participants with research experience in dreissenid mussel biology and management were identified by a literature review. State and federal agency managers were also invited to the workshop to ensure relevancy and practicality of the work­shop outcomes. A total of 28 experts (see sidebar) in mussel biology, ecology, and management attended the workshop. Close

• 27. [Article] Assessing Habitat Requirements of Pond-Breeding Amphibians in a Highly Urbanized Landscape:Implications for Management

  Management of urban aquatic habitats for native wildlife, such as amphibians, is an important contemporary goal for many municipalities. However, our understanding of how local and landscape characteristics ...

  Citation × Citation Citation Abstract Copy Title: Assessing Habitat Requirements of Pond-Breeding Amphibians in a Highly Urbanized Landscape:Implications for Management Author: Guderyahn, Laura B., Smithers, Ashley P., Mims, Meryl C. Year: 2016 Management of urban aquatic habitats for native wildlife, such as amphibians, is an important contemporary goal for many municipalities. However, our understanding of how local and landscape characteristics of urban aquatic habitat promote or inhibit amphibian occupancy and recruitment is limited. In this study, we examined amphibian community composition and occurrence patterns in ponds, wetlands, and swales of Gresham, Oregon. We collected occurrence data for five native amphibians: northwestern salamander (Ambystoma gracile), long-toed salamander (A. macrodactylum), Pacific chorus frog (Pseudacris regilla), northern red-legged frog (Rana aurora aurora), and rough-skinned newt (Taricha granulosa) as well as one non-native amphibian, the American bullfrog (Lithobates catesbeianus). One hundred sites were surveyed from 2007 to 2013. Local and landscape attributes were characterized for each site, and potential drivers of species occupancy were evaluated using a combination of multivariate approaches and generalized linear models. In general, percent impervious surface and distance to nearest forest patch, both associated with urbanization, were negatively correlated with site occupancy for all species. Non-native vegetation was also negatively associated with occupancy of three species (long-toed salamanders, Pacific chorus frogs, and northern red-legged frogs). In contrast, occupancy was positively correlated with pond depth and hydroperiod length for all species. We found evidence of two distinct groups of co-occurring amphibian species driven by habitat depth and hydroperiod. Finally, we report results of threshold analyses that examined species-specific habitat associations. This study describes urban habitat associations of a native amphibian community, identifies factors with positive, negative or mixed relationships with amphibian species, and is an important step in informing the management of urban aquatic habitat to promote persistence of native amphibians. Title: Assessing Habitat Requirements of Pond-Breeding Amphibians in a Highly Urbanized Landscape:Implications for Management Author: Guderyahn, Laura B., Smithers, Ashley P., Mims, Meryl C. Year: 2016 Management of urban aquatic habitats for native wildlife, such as amphibians, is an important contemporary goal for many municipalities. However, our understanding of how local and landscape characteristics of urban aquatic habitat promote or inhibit amphibian occupancy and recruitment is limited. In this study, we examined amphibian community composition and occurrence patterns in ponds, wetlands, and swales of Gresham, Oregon. We collected occurrence data for five native amphibians: northwestern salamander (Ambystoma gracile), long-toed salamander (A. macrodactylum), Pacific chorus frog (Pseudacris regilla), northern red-legged frog (Rana aurora aurora), and rough-skinned newt (Taricha granulosa) as well as one non-native amphibian, the American bullfrog (Lithobates catesbeianus). One hundred sites were surveyed from 2007 to 2013. Local and landscape attributes were characterized for each site, and potential drivers of species occupancy were evaluated using a combination of multivariate approaches and generalized linear models. In general, percent impervious surface and distance to nearest forest patch, both associated with urbanization, were negatively correlated with site occupancy for all species. Non-native vegetation was also negatively associated with occupancy of three species (long-toed salamanders, Pacific chorus frogs, and northern red-legged frogs). In contrast, occupancy was positively correlated with pond depth and hydroperiod length for all species. We found evidence of two distinct groups of co-occurring amphibian species driven by habitat depth and hydroperiod. Finally, we report results of threshold analyses that examined species-specific habitat associations. This study describes urban habitat associations of a native amphibian community, identifies factors with positive, negative or mixed relationships with amphibian species, and is an important step in informing the management of urban aquatic habitat to promote persistence of native amphibians. Close

• 28. [Article] CHANCE: a probabilistic model for electrical energy planning

  The energy resource planning process for electric utilities in the Northwestern United States is unique because the region relies upon a mix of hydro and thermal resources. Consequently, methods used to ...

  Citation × Citation Citation Abstract Copy Title: CHANCE: a probabilistic model for electrical energy planning Author: Wakeland, Wayne William Year: 1977 The energy resource planning process for electric utilities in the Northwestern United States is unique because the region relies upon a mix of hydro and thermal resources. Consequently, methods used to study predominantly thermal or predominantly hydro systems are not applicable. Methods are needed to determine if a particular configuration of resources will be adequate to meet future energy load, taking into account various sources of uncertainty. A literature survey of presently available methods is described, and one method is studied in some detail. A new method for analyzing systems that rely upon a mix of hydro and thermal resources is then described. The primary contributors to uncertainty in a hydro/thermal electricity supply system are: (1) uncertain rainfall and snowfall, which results in uncertain availability of hydro energy; (2) the uncertain arrival times of planned nuclear and coal plants; (3) uncertain capacity factors for thermal plants; and (4) the uncertain amount of energy that customers will require in future years. The new model, called CHANCE, characterizes each of these uncertain phenomena with a probability density function. Mathematical convolution and an algorithm developed by the author are then used to determine the probability density function for the energy margin--the difference between supply and demand. Measures of the "energy adequacy" of the supply system are then computed from the energy margin probability density function. A computer program was designed so that the conceptual model can be easily applied to any desired electrical supply system. Once an appropriate set of input assumptions h2ve been determined, they are easily entered into the computer via a question and answer sequence and stored for future use. The computer program then computes the energy adequacy of the system. The user can then change assumptions and/or resource schedules via a question and answer sequence, and recompute the energy adequacy. The computer then prepares a report showing how the alternative assumptions and/or schedules compare. CHANCE has been applied to Pacific Power and Light Company, Portland, Oregon. At the present time, about half of their energy is generated by hydro plants and the other half is generated by coal plants. Only a small fraction is generated by nuclear plants. All planned additional generation is either coal-fired or nuclear-fired. The results of applying CHANCE indicate that planned resources are not likely to be adequate to meet the needs in the early 1980's. Several evaluation exercises have also been carried out. First, CHANCE was calibrated against other electrical energy planning models used by Pacific Power and Light. Next, the sensitivity of the CHANCE model to changes in input assumptions was measured. As was anticipated, the model is highly sensitive to the assumed energy load forecast, to the assumed potential delays in the arrival of resources, and to the assumed thermal plant capacity factors. Thus, more research in these areas is warranted. Research that might lead to improvements in the CHANCE model is then outlined, and final conclusions are drawn. The final conclusions are that the CHANCE model: (1) is valid relative to the outlined scope, (2) is quite versatile and flexible, and (3) fulfills an important need in electrical energy planning. Title: CHANCE: a probabilistic model for electrical energy planning Author: Wakeland, Wayne William Year: 1977 The energy resource planning process for electric utilities in the Northwestern United States is unique because the region relies upon a mix of hydro and thermal resources. Consequently, methods used to study predominantly thermal or predominantly hydro systems are not applicable. Methods are needed to determine if a particular configuration of resources will be adequate to meet future energy load, taking into account various sources of uncertainty. A literature survey of presently available methods is described, and one method is studied in some detail. A new method for analyzing systems that rely upon a mix of hydro and thermal resources is then described. The primary contributors to uncertainty in a hydro/thermal electricity supply system are: (1) uncertain rainfall and snowfall, which results in uncertain availability of hydro energy; (2) the uncertain arrival times of planned nuclear and coal plants; (3) uncertain capacity factors for thermal plants; and (4) the uncertain amount of energy that customers will require in future years. The new model, called CHANCE, characterizes each of these uncertain phenomena with a probability density function. Mathematical convolution and an algorithm developed by the author are then used to determine the probability density function for the energy margin--the difference between supply and demand. Measures of the "energy adequacy" of the supply system are then computed from the energy margin probability density function. A computer program was designed so that the conceptual model can be easily applied to any desired electrical supply system. Once an appropriate set of input assumptions h2ve been determined, they are easily entered into the computer via a question and answer sequence and stored for future use. The computer program then computes the energy adequacy of the system. The user can then change assumptions and/or resource schedules via a question and answer sequence, and recompute the energy adequacy. The computer then prepares a report showing how the alternative assumptions and/or schedules compare. CHANCE has been applied to Pacific Power and Light Company, Portland, Oregon. At the present time, about half of their energy is generated by hydro plants and the other half is generated by coal plants. Only a small fraction is generated by nuclear plants. All planned additional generation is either coal-fired or nuclear-fired. The results of applying CHANCE indicate that planned resources are not likely to be adequate to meet the needs in the early 1980's. Several evaluation exercises have also been carried out. First, CHANCE was calibrated against other electrical energy planning models used by Pacific Power and Light. Next, the sensitivity of the CHANCE model to changes in input assumptions was measured. As was anticipated, the model is highly sensitive to the assumed energy load forecast, to the assumed potential delays in the arrival of resources, and to the assumed thermal plant capacity factors. Thus, more research in these areas is warranted. Research that might lead to improvements in the CHANCE model is then outlined, and final conclusions are drawn. The final conclusions are that the CHANCE model: (1) is valid relative to the outlined scope, (2) is quite versatile and flexible, and (3) fulfills an important need in electrical energy planning. Close

• 29. [Article] Children's drama available for the elementary school children of Portland, Oregon

  This thesis was an endeavor to find the drama available for the elementary children of Portland, Oregon. In deciding what drama was for children two different forms were first researched. Children’s theatre ...

  Citation × Citation Citation Abstract Copy Title: Children's drama available for the elementary school children of Portland, Oregon Author: Gender, Margaret Othus Year: 1967 This thesis was an endeavor to find the drama available for the elementary children of Portland, Oregon. In deciding what drama was for children two different forms were first researched. Children’s theatre done by adults such as in community services, educational programs and professional and commercial theatres were studied. Drama by children, referred to as the less formalized drama, creative dramatics was also investigated. To further examine the background of children’s theatre in the United States, various children’s theatres around the country were studied including the University Children’s Theatre at Northwestern under the direction of Winifred Ward and Goodman Memorial Children’s Theatre in Chicago under the direction of Charlotte Chorpenning. With the advent of the educational field into children’s theatre culminating with the Children’s Theatre Conference the movement became wide spread throughout the United States. A great deal has been done to spark children’s drama not only in the viewing of children’s plays in production but affording children actual participation in creative drama workshops and children’s productions. More and more community theatres, commercial groups and universities are doing children’s drama throughout the nation. In an effort to find what was being offered to the Portland children in drama, the Portland Public Grade Schools were first approached. With the help of the Language Arts Supervisor five areas of drama for children were researched through reading and interviews. Although the Portland Public Grade Schools have no drama courses instructed by specific drama teachers they do encourage drama to be correlated into the classroom program and taught in “in service” courses for their teachers. The “model school program” has drama as a definite course and the Portland schools offer a summer school which has a creative drama course available to the elementary school children. The University of Portland, a Catholic university in Portland, has achieved the most definite progress in the Portland area in children’s theatre. They not only produce children’s plays during the school year but offer creative drama and playwriting in their course of study. Under the instruction and production of Mrs. Catherine Roberts for the last six years they are striving to bring children’s theatre to the Portland children and their teachers. Portland does offer some excellent theatre for children in the community. The Portland Junior League, a service group, has nationally been involved throughout the years with their children’s play productions by their groups for the school children of their communities. Now, after turning their productions over to Portland University they still maintain a very worthwhile program of puppetry for the school children of Portland. Portland Junior Civic Theatre, one of the oldest children’s theatre groups in Portland, not only produces children’s productions by children but conducts a children’s drama school throughout the year. The Portland Park Bureau also takes an active part particularly during the summer in children’s drama and training. The newest to Portland is the Playmaker’s Group, relatively young but eager in its endeavor for the children of the area. Their efforts include both productions and schooling on a creative drama promise, with improvisational plays by the adult Playmaker casts. Children’s theatre in Portland is developing but has faced many problems and has many more to surmount. The progress of the active workers in this movement show hope for the future for the children of Portland. The appendix of the thesis is devoted to several programs involved with the teaching of drama. First is a course in creative drama offered to college students in the colleges and universities having such courses in their curriculum. A creative drama course correlated with the regular classroom subjects in the Portland Grade School Curriculum is also included. Last, a summer school plan for community theatre is shown. All the arts combine in the theatre, decor, the dance, impersonation, effective speech, the song, pantomime, the projection of personality, the art of suppressing self and even ill will, for the unity of effort. Hundreds of other arts could be listed including the art of living together and the art of creative imagination. That is why the play can never be omitted from child education. Title: Children's drama available for the elementary school children of Portland, Oregon Author: Gender, Margaret Othus Year: 1967 This thesis was an endeavor to find the drama available for the elementary children of Portland, Oregon. In deciding what drama was for children two different forms were first researched. Children’s theatre done by adults such as in community services, educational programs and professional and commercial theatres were studied. Drama by children, referred to as the less formalized drama, creative dramatics was also investigated. To further examine the background of children’s theatre in the United States, various children’s theatres around the country were studied including the University Children’s Theatre at Northwestern under the direction of Winifred Ward and Goodman Memorial Children’s Theatre in Chicago under the direction of Charlotte Chorpenning. With the advent of the educational field into children’s theatre culminating with the Children’s Theatre Conference the movement became wide spread throughout the United States. A great deal has been done to spark children’s drama not only in the viewing of children’s plays in production but affording children actual participation in creative drama workshops and children’s productions. More and more community theatres, commercial groups and universities are doing children’s drama throughout the nation. In an effort to find what was being offered to the Portland children in drama, the Portland Public Grade Schools were first approached. With the help of the Language Arts Supervisor five areas of drama for children were researched through reading and interviews. Although the Portland Public Grade Schools have no drama courses instructed by specific drama teachers they do encourage drama to be correlated into the classroom program and taught in “in service” courses for their teachers. The “model school program” has drama as a definite course and the Portland schools offer a summer school which has a creative drama course available to the elementary school children. The University of Portland, a Catholic university in Portland, has achieved the most definite progress in the Portland area in children’s theatre. They not only produce children’s plays during the school year but offer creative drama and playwriting in their course of study. Under the instruction and production of Mrs. Catherine Roberts for the last six years they are striving to bring children’s theatre to the Portland children and their teachers. Portland does offer some excellent theatre for children in the community. The Portland Junior League, a service group, has nationally been involved throughout the years with their children’s play productions by their groups for the school children of their communities. Now, after turning their productions over to Portland University they still maintain a very worthwhile program of puppetry for the school children of Portland. Portland Junior Civic Theatre, one of the oldest children’s theatre groups in Portland, not only produces children’s productions by children but conducts a children’s drama school throughout the year. The Portland Park Bureau also takes an active part particularly during the summer in children’s drama and training. The newest to Portland is the Playmaker’s Group, relatively young but eager in its endeavor for the children of the area. Their efforts include both productions and schooling on a creative drama promise, with improvisational plays by the adult Playmaker casts. Children’s theatre in Portland is developing but has faced many problems and has many more to surmount. The progress of the active workers in this movement show hope for the future for the children of Portland. The appendix of the thesis is devoted to several programs involved with the teaching of drama. First is a course in creative drama offered to college students in the colleges and universities having such courses in their curriculum. A creative drama course correlated with the regular classroom subjects in the Portland Grade School Curriculum is also included. Last, a summer school plan for community theatre is shown. All the arts combine in the theatre, decor, the dance, impersonation, effective speech, the song, pantomime, the projection of personality, the art of suppressing self and even ill will, for the unity of effort. Hundreds of other arts could be listed including the art of living together and the art of creative imagination. That is why the play can never be omitted from child education. Close

• 30. [Article] Investigating the Potential of Land Use Modifications to Mitigate the Respiratory Health Impacts of NO2: A Case Study in the Portland-Vancouver Metropolitan Area

  The health impacts of urban air pollution are a growing concern in our rapidly urbanizing world. Urban air pollutants show high intra-urban spatial variability linked to urban land use and land cover (LULC). ...

  Citation × Citation Citation Abstract Copy Title: Investigating the Potential of Land Use Modifications to Mitigate the Respiratory Health Impacts of NO2: A Case Study in the Portland-Vancouver Metropolitan Area Author: Rao, Meenakshi Year: 2016 The health impacts of urban air pollution are a growing concern in our rapidly urbanizing world. Urban air pollutants show high intra-urban spatial variability linked to urban land use and land cover (LULC). This correlation of air pollutants with LULC is widely recognized; LULC data is an integral input into a wide range of models, especially land use regression models developed by epidemiologists to study the impact of air pollution on human health. Given the demonstrated links between LULC and urban air pollution, and between urban air pollution and health, an interesting question arises: what is the potential of LULC modifications to mitigate the health impacts of urban air pollution? In this dissertation we assess the potential of LULC modifications to mitigate the health impacts of NO2, a respiratory irritant and strong marker for combustion-related air pollution, in the Portland-Vancouver metropolitan area in northwestern USA. We begin by measuring summer and winter NO2 in the area using a spatially dense network of passive NO2 samplers. We next develop an annual average model for NO2 based on the observational data, using random forest -- for the first time in the realm of urban air pollution -- to disentangle the effects of highly correlated LULC variables on ambient NO2 concentrations. We apply this random forest (LURF) model to a 200m spatial grid covering the study area, and use this 200m LURF model to quantify the effect of different urban land use categories on ambient concentrations of NO2. Using the changes in ambient NO2 concentrations resulting from land use modifications as input to BenMAP (a health benefits assessment tool form the US EPA), we assess the NO2-related health impact associated with each land use category and its modifications. We demonstrate how the LURF model can be used to assess the respiratory health benefits of competing land use modifications, including city-wide and local-scale mitigation strategies based on modifying tree canopy and vehicle miles traveled (VMT). Planting trees is a common land cover modification strategy undertaken by cities to reduce air pollution. Statistical models such as LUR and LURF demonstrate a correlation between tree cover and reduced air pollution, but they cannot demonstrate causation. Hence, we run the atmospheric chemistry and transport model CMAQ to examine to what extent the dry deposition mechanism can explain the reduction of NO2 which statistical models associate with tree canopy. Results from our research indicate that even though the Portland-Vancouver area is in compliance with the US EPA NO2 standards, ambient concentrations of NO2 still create an annual health burden of at least $40 million USD. Our model suggests that NO2 associated with high intensity development and VMT may be creating an annual health burden of $7 million and $3.3 million USD respectively. Existing tree canopy, on the other hand, is associated with an annual health benefit of $1.4 million USD. LULC modifications can mitigate some fraction of this health burden. A 2% increase in tree canopy across the study area may reduce incidence rates of asthma exacerbation by as much as 7%. We also find that increasing tree canopy is a more effective strategy than reducing VMT in terms of mitigating the health burden of NO2. CMAQ indicates that the amount of NO2 removed by dry deposition is an order of magnitude smaller than that predicted by our statistical model. About one-third of the difference can be explained by the lower NO2 values predicted by CMAQ, and one-third may be attributable to parameterization of stomatal uptake. Title: Investigating the Potential of Land Use Modifications to Mitigate the Respiratory Health Impacts of NO2: A Case Study in the Portland-Vancouver Metropolitan Area Author: Rao, Meenakshi Year: 2016 The health impacts of urban air pollution are a growing concern in our rapidly urbanizing world. Urban air pollutants show high intra-urban spatial variability linked to urban land use and land cover (LULC). This correlation of air pollutants with LULC is widely recognized; LULC data is an integral input into a wide range of models, especially land use regression models developed by epidemiologists to study the impact of air pollution on human health. Given the demonstrated links between LULC and urban air pollution, and between urban air pollution and health, an interesting question arises: what is the potential of LULC modifications to mitigate the health impacts of urban air pollution? In this dissertation we assess the potential of LULC modifications to mitigate the health impacts of NO2, a respiratory irritant and strong marker for combustion-related air pollution, in the Portland-Vancouver metropolitan area in northwestern USA. We begin by measuring summer and winter NO2 in the area using a spatially dense network of passive NO2 samplers. We next develop an annual average model for NO2 based on the observational data, using random forest -- for the first time in the realm of urban air pollution -- to disentangle the effects of highly correlated LULC variables on ambient NO2 concentrations. We apply this random forest (LURF) model to a 200m spatial grid covering the study area, and use this 200m LURF model to quantify the effect of different urban land use categories on ambient concentrations of NO2. Using the changes in ambient NO2 concentrations resulting from land use modifications as input to BenMAP (a health benefits assessment tool form the US EPA), we assess the NO2-related health impact associated with each land use category and its modifications. We demonstrate how the LURF model can be used to assess the respiratory health benefits of competing land use modifications, including city-wide and local-scale mitigation strategies based on modifying tree canopy and vehicle miles traveled (VMT). Planting trees is a common land cover modification strategy undertaken by cities to reduce air pollution. Statistical models such as LUR and LURF demonstrate a correlation between tree cover and reduced air pollution, but they cannot demonstrate causation. Hence, we run the atmospheric chemistry and transport model CMAQ to examine to what extent the dry deposition mechanism can explain the reduction of NO2 which statistical models associate with tree canopy. Results from our research indicate that even though the Portland-Vancouver area is in compliance with the US EPA NO2 standards, ambient concentrations of NO2 still create an annual health burden of at least $40 million USD. Our model suggests that NO2 associated with high intensity development and VMT may be creating an annual health burden of $7 million and $3.3 million USD respectively. Existing tree canopy, on the other hand, is associated with an annual health benefit of $1.4 million USD. LULC modifications can mitigate some fraction of this health burden. A 2% increase in tree canopy across the study area may reduce incidence rates of asthma exacerbation by as much as 7%. We also find that increasing tree canopy is a more effective strategy than reducing VMT in terms of mitigating the health burden of NO2. CMAQ indicates that the amount of NO2 removed by dry deposition is an order of magnitude smaller than that predicted by our statistical model. About one-third of the difference can be explained by the lower NO2 values predicted by CMAQ, and one-third may be attributable to parameterization of stomatal uptake. Close