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• 91. [Article] Mammalian Community Recovery from Volcanic Eruptions in the Cenozoic of North America

  It is clear that ecosystems are devastated after a volcanic eruption coats the landscape with a layer of ash; however, the ecological recovery of mammalian communities after eruptions is poorly understood. ...

  Citation × Citation Citation Abstract Copy Title: Mammalian Community Recovery from Volcanic Eruptions in the Cenozoic of North America Author: Famoso, Nicholas Year: 2017 It is clear that ecosystems are devastated after a volcanic eruption coats the landscape with a layer of ash; however, the ecological recovery of mammalian communities after eruptions is poorly understood. Volcanic eruptions vary with magnitude and type and only a fraction of them have been analyzed for effects on mammalian communities. To better understand mammalian community recovery, I investigated three different lines of evidence. First, I created a new numeric metric for statistically analyzing reproductive strategies in mammals and tested the impact of diet and body size on reproductive strategies within a phylogenetic framework as proof of concept. The trend of lower reproductive rates and larger body size hold true for herbivores and omnivores, but different trajectories exist for carnivores. Second, I investigated how species richness, evenness, and similarity change across volcanic boundaries in the 1980 Mount St. Helens (MSH), Washington, and 1914-1917 Mount Lassen, California, eruptions. Richness and evenness remain unchanged in Lassen. MSH saw an immediate drop in richness followed by an increase over five years to pre-eruptive levels. Chord distance analysis suggests no long-term change in the Lassen fauna. The pre- and post-MSH fauna are different from one another. The post-eruptive fauna was more similar to neighboring regions. Lastly, I tested whether the Oligocene horse Miohippus demonstrated morphological changes across the volcanic Picture Gorge ignimbrite (PGI; 29.069 Ma) in the John Day Formation of Oregon. Variation in upper and lower teeth was first tested to define a single species in the assemblage. Length, width, and wear of teeth were compared across the PGI and there were no significant differences between pre- and post-PGI assemblages. It is clear from my results that larger eruptions tend to have a greater impact on mammalian community recovery than smaller eruptions, but ultimately, mammalian populations are robust and the presence of neighboring communities is important for recolonizing devastated areas. There are two supplemental files associated with this dissertation, a CSV file of raw data downloaded for Chapter III and an excel file of raw data and coefficient of variation calculations for Chapter IV. This dissertation includes both unpublished and co-authored material. Title: Mammalian Community Recovery from Volcanic Eruptions in the Cenozoic of North America Author: Famoso, Nicholas Year: 2017 It is clear that ecosystems are devastated after a volcanic eruption coats the landscape with a layer of ash; however, the ecological recovery of mammalian communities after eruptions is poorly understood. Volcanic eruptions vary with magnitude and type and only a fraction of them have been analyzed for effects on mammalian communities. To better understand mammalian community recovery, I investigated three different lines of evidence. First, I created a new numeric metric for statistically analyzing reproductive strategies in mammals and tested the impact of diet and body size on reproductive strategies within a phylogenetic framework as proof of concept. The trend of lower reproductive rates and larger body size hold true for herbivores and omnivores, but different trajectories exist for carnivores. Second, I investigated how species richness, evenness, and similarity change across volcanic boundaries in the 1980 Mount St. Helens (MSH), Washington, and 1914-1917 Mount Lassen, California, eruptions. Richness and evenness remain unchanged in Lassen. MSH saw an immediate drop in richness followed by an increase over five years to pre-eruptive levels. Chord distance analysis suggests no long-term change in the Lassen fauna. The pre- and post-MSH fauna are different from one another. The post-eruptive fauna was more similar to neighboring regions. Lastly, I tested whether the Oligocene horse Miohippus demonstrated morphological changes across the volcanic Picture Gorge ignimbrite (PGI; 29.069 Ma) in the John Day Formation of Oregon. Variation in upper and lower teeth was first tested to define a single species in the assemblage. Length, width, and wear of teeth were compared across the PGI and there were no significant differences between pre- and post-PGI assemblages. It is clear from my results that larger eruptions tend to have a greater impact on mammalian community recovery than smaller eruptions, but ultimately, mammalian populations are robust and the presence of neighboring communities is important for recolonizing devastated areas. There are two supplemental files associated with this dissertation, a CSV file of raw data downloaded for Chapter III and an excel file of raw data and coefficient of variation calculations for Chapter IV. This dissertation includes both unpublished and co-authored material. Close

• 92. [Article] Protecting Stream Ecosystem Health in the Face of Rapid Urbanization and Climate Change

  The ability to anticipate and evaluate the combined impacts of urbanization and climate change on streamflow regimes is critical to developing proactive strategies that protect aquatic ecosystems. I developed ...

  Citation × Citation Citation Abstract Copy Title: Protecting Stream Ecosystem Health in the Face of Rapid Urbanization and Climate Change Author: Wu, Hong Year: 2015 The ability to anticipate and evaluate the combined impacts of urbanization and climate change on streamflow regimes is critical to developing proactive strategies that protect aquatic ecosystems. I developed an interdisciplinary modeling framework to compare and contrast the effectiveness of integrated stormwater management, or its absence, with two regional growth patterns for maintaining streamflow regimes in the context of climate change. In three adjacent urbanizing watersheds in Oregon's Willamette Valley, I conducted a three-step sequence to: 1) simulate land use change under four future development scenarios with the agent-based model Envision; 2) model resultant hydrological change under the recent past and two future climate regimes using the Soil and Water Assessment Tool; and 3) assess scenario impacts on streamflow regimes using 10 ecologically significant flow metrics. I evaluated each scenario in each basin using a flow metric typology based on the magnitude of change in each metric and the degree to which such changes could be mitigated, i.e., insensitive, sensitive and manageable, and sensitive and resistant. My results demonstrated distinct signatures of urbanization and climate change on flow regimes. Urbanization and climate change in isolation led to significant flow alterations in all three basins. Urbanization consistently led to increases in flow regime flashiness and severity of extreme flow events, whereas climate change primarily caused a drying trend. Climate change tended to exacerbate the impacts of urbanization but also mitigated urban impacts on several metrics. The combined impacts of urbanization and climate change caused substantial changes to metric sensitivities, which further differed by basin and climate regime, highlighting the uncertainties of streamflow regime responses to development and the value of spatially explicit modeling that can reveal complex interactions between natural and human systems. Scenario comparisons demonstrated the importance of integrated stormwater management and, secondarily, compact regional growth. My findings reveal the need for regional flow-ecology research that substantiates the ecological significance of each flow metric, develops specific targets for manageable ones, and explores potential remedies for resistant ones. The interdisciplinary modeling framework shows promise as a transferable tool for local watershed management. This dissertation includes previously unpublished co-authored material. Title: Protecting Stream Ecosystem Health in the Face of Rapid Urbanization and Climate Change Author: Wu, Hong Year: 2015 The ability to anticipate and evaluate the combined impacts of urbanization and climate change on streamflow regimes is critical to developing proactive strategies that protect aquatic ecosystems. I developed an interdisciplinary modeling framework to compare and contrast the effectiveness of integrated stormwater management, or its absence, with two regional growth patterns for maintaining streamflow regimes in the context of climate change. In three adjacent urbanizing watersheds in Oregon's Willamette Valley, I conducted a three-step sequence to: 1) simulate land use change under four future development scenarios with the agent-based model Envision; 2) model resultant hydrological change under the recent past and two future climate regimes using the Soil and Water Assessment Tool; and 3) assess scenario impacts on streamflow regimes using 10 ecologically significant flow metrics. I evaluated each scenario in each basin using a flow metric typology based on the magnitude of change in each metric and the degree to which such changes could be mitigated, i.e., insensitive, sensitive and manageable, and sensitive and resistant. My results demonstrated distinct signatures of urbanization and climate change on flow regimes. Urbanization and climate change in isolation led to significant flow alterations in all three basins. Urbanization consistently led to increases in flow regime flashiness and severity of extreme flow events, whereas climate change primarily caused a drying trend. Climate change tended to exacerbate the impacts of urbanization but also mitigated urban impacts on several metrics. The combined impacts of urbanization and climate change caused substantial changes to metric sensitivities, which further differed by basin and climate regime, highlighting the uncertainties of streamflow regime responses to development and the value of spatially explicit modeling that can reveal complex interactions between natural and human systems. Scenario comparisons demonstrated the importance of integrated stormwater management and, secondarily, compact regional growth. My findings reveal the need for regional flow-ecology research that substantiates the ecological significance of each flow metric, develops specific targets for manageable ones, and explores potential remedies for resistant ones. The interdisciplinary modeling framework shows promise as a transferable tool for local watershed management. This dissertation includes previously unpublished co-authored material. Close

• 93. [Article] Assessing and Responding to Short-Term Rentals in Oregon: Enabling the Benefits of the Sharing Economy

  67 pages

  Citation × Citation Citation Abstract Copy Title: Assessing and Responding to Short-Term Rentals in Oregon: Enabling the Benefits of the Sharing Economy Author: DINATALE, SADIE Year: 2017 67 pages Title: Assessing and Responding to Short-Term Rentals in Oregon: Enabling the Benefits of the Sharing Economy Author: DINATALE, SADIE Year: 2017 67 pages Close

• 94. [Article] Essays on Income Inequality and the Environment

  This dissertation considers two of the most pressing concerns of the current time, income inequality and exposure to pollution, and provides evidence that these two concerns may in fact be causally linked. ...

  Citation × Citation Citation Abstract Copy Title: Essays on Income Inequality and the Environment Author: Voorheis, John Year: 2016 This dissertation considers two of the most pressing concerns of the current time, income inequality and exposure to pollution, and provides evidence that these two concerns may in fact be causally linked. In order to do this, I assemble novel datasets on income inequality and pollution exposure, and propose an strategy for causally identifying the effect of the former on the latter. In the first substantive chapter, I develop a new dataset on income inequality measured at the US state and metropolitan area level. I compare the trends in income inequality measured using different income definitions. In general, pre-tax, pre-transfer income inequality has increased in most states since 1980, but post-fiscal income inequality has seen slow or no growth since about 2000. I conduct inference on how income inequality has changed using a semi-parametric bootstrap method, and consider potential correlates with state-level income inequality. I find that de-unionization is perhaps the most important factor driving rising inequality. In the second substantive chapter, I leverage satellite-derived remote sensing data on ground-level concentrations for two important pollutants (NOx and PM2.5) to measure the distribution of pollution exposure. I propose a dashboard approach to measuring environmental inequality and environmental justice, proposing and applying several candidate measures to the satellite datasets. I find that environmental inequality has largely decreased since 1998, as has average exposure. I consider potential correlations between neighborhood demographics and the distribution of exposure, but find inconclusive results. In the third substantive chapter, I attempt to resolve this ambiguity by considering whether rising income inequality within metropolitan areas (the subject of the first chapter) might causally affect the distribution of exposure across people (the subject of the second). Using a simulated instrumental variables identification strategy designed to address potential endogeneity due to locational sorting, I find that income inequality decreases the average level of exposure, but increases environmental inequality. I argue this is consistent with the benefits of pollution reduction accruing to the most advantaged, and provide evidence that this may work through the political system: inequality increases the responsiveness of politicians to the environmental demands of the rich. Title: Essays on Income Inequality and the Environment Author: Voorheis, John Year: 2016 This dissertation considers two of the most pressing concerns of the current time, income inequality and exposure to pollution, and provides evidence that these two concerns may in fact be causally linked. In order to do this, I assemble novel datasets on income inequality and pollution exposure, and propose an strategy for causally identifying the effect of the former on the latter. In the first substantive chapter, I develop a new dataset on income inequality measured at the US state and metropolitan area level. I compare the trends in income inequality measured using different income definitions. In general, pre-tax, pre-transfer income inequality has increased in most states since 1980, but post-fiscal income inequality has seen slow or no growth since about 2000. I conduct inference on how income inequality has changed using a semi-parametric bootstrap method, and consider potential correlates with state-level income inequality. I find that de-unionization is perhaps the most important factor driving rising inequality. In the second substantive chapter, I leverage satellite-derived remote sensing data on ground-level concentrations for two important pollutants (NOx and PM2.5) to measure the distribution of pollution exposure. I propose a dashboard approach to measuring environmental inequality and environmental justice, proposing and applying several candidate measures to the satellite datasets. I find that environmental inequality has largely decreased since 1998, as has average exposure. I consider potential correlations between neighborhood demographics and the distribution of exposure, but find inconclusive results. In the third substantive chapter, I attempt to resolve this ambiguity by considering whether rising income inequality within metropolitan areas (the subject of the first chapter) might causally affect the distribution of exposure across people (the subject of the second). Using a simulated instrumental variables identification strategy designed to address potential endogeneity due to locational sorting, I find that income inequality decreases the average level of exposure, but increases environmental inequality. I argue this is consistent with the benefits of pollution reduction accruing to the most advantaged, and provide evidence that this may work through the political system: inequality increases the responsiveness of politicians to the environmental demands of the rich. Close

• 95. [Article] Essays on the Recreational Value of Avian Biodiversity

  This dissertation uses a convenience sample of members of eBird, a large citizen science project maintained by the Cornell University's Laboratory of Ornithology, to explore the value of avian biodiversity ...

  Citation × Citation Citation Abstract Copy Title: Essays on the Recreational Value of Avian Biodiversity Author: Kolstoe, Sonja Year: 2016 This dissertation uses a convenience sample of members of eBird, a large citizen science project maintained by the Cornell University's Laboratory of Ornithology, to explore the value of avian biodiversity to bird watchers. Panel data (i.e. longitudinal data) are highly desirable for preference estimation. Fortuitously, the diaries of birding excursions by eBird members provide a rich source of spatial data on trips taken, over time by the same individuals, to a variety of birding destinations. Origin and destination data can be combined with exogenous species prevalence information. These combined data sources permit estimation of utility-theoretic choice models that allow derivation of the marginal utilities of avian biodiversity measures as well as the marginal utility of net income (i.e. consumption of other goods and services). Ratios of these marginal utilities yield marginal willingness to pay (MWTP) estimates for numbers of bird species (or numbers of species of different types, in richer specifications). MWTP for levels of other attributes of birding destinations are also derived (e.g. ecosystem type, management regime, seasonal variations, a time trend).\\ The chapters are organized as follows: Chapter 2 is a stand-alone paper that demonstrates the feasibility of a travel-cost based random utility model with the eBird data. This chapter focuses on measuring the total number of bird species at each birding hotspot in Washington and Oregon states. This chapter does not differentiate among types of birders beyond using their recent birding activities in an analysis of habit formation or variety-seeking behavior. For this model, beyond past behavior, a representative consumer is postulated. Chapter 3 starts from the basic specifications identified in Chapter 2 and explores heterogeneous preferences among consumers as well as their preferences for species richness and for different categories of birds. This chapter explores whether different types of birds are relatively more attractive to different types of birders (for example, by gender or by age or by neighborhood characteristics and educational attainment). Chapter 4 is an extension of the work in Chapter 3 to explore how changing site attributes in the face of climate change effects birder welfare. This dissertation includes previously unpublished co-authored material. Title: Essays on the Recreational Value of Avian Biodiversity Author: Kolstoe, Sonja Year: 2016 This dissertation uses a convenience sample of members of eBird, a large citizen science project maintained by the Cornell University's Laboratory of Ornithology, to explore the value of avian biodiversity to bird watchers. Panel data (i.e. longitudinal data) are highly desirable for preference estimation. Fortuitously, the diaries of birding excursions by eBird members provide a rich source of spatial data on trips taken, over time by the same individuals, to a variety of birding destinations. Origin and destination data can be combined with exogenous species prevalence information. These combined data sources permit estimation of utility-theoretic choice models that allow derivation of the marginal utilities of avian biodiversity measures as well as the marginal utility of net income (i.e. consumption of other goods and services). Ratios of these marginal utilities yield marginal willingness to pay (MWTP) estimates for numbers of bird species (or numbers of species of different types, in richer specifications). MWTP for levels of other attributes of birding destinations are also derived (e.g. ecosystem type, management regime, seasonal variations, a time trend).\\ The chapters are organized as follows: Chapter 2 is a stand-alone paper that demonstrates the feasibility of a travel-cost based random utility model with the eBird data. This chapter focuses on measuring the total number of bird species at each birding hotspot in Washington and Oregon states. This chapter does not differentiate among types of birders beyond using their recent birding activities in an analysis of habit formation or variety-seeking behavior. For this model, beyond past behavior, a representative consumer is postulated. Chapter 3 starts from the basic specifications identified in Chapter 2 and explores heterogeneous preferences among consumers as well as their preferences for species richness and for different categories of birds. This chapter explores whether different types of birds are relatively more attractive to different types of birders (for example, by gender or by age or by neighborhood characteristics and educational attainment). Chapter 4 is an extension of the work in Chapter 3 to explore how changing site attributes in the face of climate change effects birder welfare. This dissertation includes previously unpublished co-authored material. Close

• 96. [Article] Oregon Compensatory Wetland Mitigation: Spatial and Temporal Patterns 2000-2016

  58 pages

  Citation × Citation Citation Abstract Copy Title: Oregon Compensatory Wetland Mitigation: Spatial and Temporal Patterns 2000-2016 Author: Lockwood, Ethan Year: 2017 58 pages Title: Oregon Compensatory Wetland Mitigation: Spatial and Temporal Patterns 2000-2016 Author: Lockwood, Ethan Year: 2017 58 pages Close

• 97. [Article] State Funding and Planning Mechanisms to Reduce Greenhouse Gas Emissions from the Transportation Sector

  38 pages

  Citation × Citation Citation Abstract Copy Title: State Funding and Planning Mechanisms to Reduce Greenhouse Gas Emissions from the Transportation Sector Author: Isbell, Rory Year: 2017, 2016 38 pages Title: State Funding and Planning Mechanisms to Reduce Greenhouse Gas Emissions from the Transportation Sector Author: Isbell, Rory Year: 2017, 2016 38 pages Close