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• 1. [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

• 2. [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

• 3. [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