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• 21. [Article] Using advanced spreadsheet features for agricultural GIS applications

  A GIS analysis procedure was developed to explore relationships between imagery, yield data, soil information, and other assessments of a field or orchard. A set of conversion utilities, a spreadsheet, ...

  Citation × Citation Citation Abstract Copy Title: Using advanced spreadsheet features for agricultural GIS applications Author: Halbleib, Michael D. A GIS analysis procedure was developed to explore relationships between imagery, yield data, soil information, and other assessments of a field or orchard. A set of conversion utilities, a spreadsheet, and an inexpensive shape file viewer were used to manipulate, plot, and display data. Specific features described include procedures used to: 1) display automated yield monitoring and aerial imagery data as surface maps for visual analysis, 2) generate maps from gridded soil sampling schemes that display either the collected soil data values or management information derived from further manipulation of the sample values, 3) evaluate relationships among data layers such as yield monitor, imagery, and soil data, 4) conduct an upper boundary line evaluation of potential yield-limiting factors. The analysis process is demonstrated on wheat, meadowfoam, and hazelnut data, from crops grown in Oregon. Title: Using advanced spreadsheet features for agricultural GIS applications Author: Halbleib, Michael D. A GIS analysis procedure was developed to explore relationships between imagery, yield data, soil information, and other assessments of a field or orchard. A set of conversion utilities, a spreadsheet, and an inexpensive shape file viewer were used to manipulate, plot, and display data. Specific features described include procedures used to: 1) display automated yield monitoring and aerial imagery data as surface maps for visual analysis, 2) generate maps from gridded soil sampling schemes that display either the collected soil data values or management information derived from further manipulation of the sample values, 3) evaluate relationships among data layers such as yield monitor, imagery, and soil data, 4) conduct an upper boundary line evaluation of potential yield-limiting factors. The analysis process is demonstrated on wheat, meadowfoam, and hazelnut data, from crops grown in Oregon. Close

• 22. [Article] Distribution and prediction of Swiss needle cast of Douglas-fir in coastal Oregon

  This study was directed to improve our understanding of the ecology of Swiss needle cast (SNC) of Douglas-fir, a disease that produces extensive damage to forests and plantation in the coastal region of ...

  Citation × Citation Citation Abstract Copy Title: Distribution and prediction of Swiss needle cast of Douglas-fir in coastal Oregon Author: Rosso, Pablo H. This study was directed to improve our understanding of the ecology of Swiss needle cast (SNC) of Douglas-fir, a disease that produces extensive damage to forests and plantation in the coastal region of Oregon and Washington. A disease prediction model for the coastal area of Oregon was built by establishing the relationship between the distribution of disease severity and the environment. Currently available methods of determining the distribution of SNC were analyzed, and the possibility of mapping the disease using Landsat TM satellite images was explored. Two types of regression approaches were used to study the relationship between disease severity and climate, topography, soil and forest stand characteristics. Although both types provided useful information and insight, the multiple regression approach was chosen over the regression tree analysis to build the model, due to its capacity to produce a continuous prediction response. Fog occurrence, precipitation, temperature, elevation and slope aspect, were the variables that contributed to explain most of the disease severity variability. Findings agree with and formalize our previous understanding of the ecology of SNC: cool and wet conditions in summer appear to increase disease severity. When the model was applied to past climate conditions, retrospective predictions suggest that changes in climate in the last two decades could help to explain the observed recent regional increase in SNC disease severity. The resulting model was used to construct a disease prediction map. This map showed an accuracy equivalent to the currently available SNC aerial survey. The prediction model, however, is able to produce a continuous prediction surface, more suitable for testing and appropriate for assisting in disease management and research. A strong relationship between mature stand canopy defoliation and the Landsat TM indices greenness and brightness, indicates that it is possible to use satellite imagery to map SNC. In contrast, young stands showed high variability, most likely due to the relatively high proportion of exposed understory vegetation. The possibility of mapping stand defoliation is of great importance because this symptom can be directly linked to tree growth and forest productivity. Satellite imagery can be used in future and in retrospective disease mapping. Title: Distribution and prediction of Swiss needle cast of Douglas-fir in coastal Oregon Author: Rosso, Pablo H. This study was directed to improve our understanding of the ecology of Swiss needle cast (SNC) of Douglas-fir, a disease that produces extensive damage to forests and plantation in the coastal region of Oregon and Washington. A disease prediction model for the coastal area of Oregon was built by establishing the relationship between the distribution of disease severity and the environment. Currently available methods of determining the distribution of SNC were analyzed, and the possibility of mapping the disease using Landsat TM satellite images was explored. Two types of regression approaches were used to study the relationship between disease severity and climate, topography, soil and forest stand characteristics. Although both types provided useful information and insight, the multiple regression approach was chosen over the regression tree analysis to build the model, due to its capacity to produce a continuous prediction response. Fog occurrence, precipitation, temperature, elevation and slope aspect, were the variables that contributed to explain most of the disease severity variability. Findings agree with and formalize our previous understanding of the ecology of SNC: cool and wet conditions in summer appear to increase disease severity. When the model was applied to past climate conditions, retrospective predictions suggest that changes in climate in the last two decades could help to explain the observed recent regional increase in SNC disease severity. The resulting model was used to construct a disease prediction map. This map showed an accuracy equivalent to the currently available SNC aerial survey. The prediction model, however, is able to produce a continuous prediction surface, more suitable for testing and appropriate for assisting in disease management and research. A strong relationship between mature stand canopy defoliation and the Landsat TM indices greenness and brightness, indicates that it is possible to use satellite imagery to map SNC. In contrast, young stands showed high variability, most likely due to the relatively high proportion of exposed understory vegetation. The possibility of mapping stand defoliation is of great importance because this symptom can be directly linked to tree growth and forest productivity. Satellite imagery can be used in future and in retrospective disease mapping. Close

• 23. [Article] Women's voices : the emergence of female identity in Bleak House and Little Dorrit

  Dedicated to recording, portraying, and indicting the social inequities that he witnessed in nineteenth century Victorian England, one of Charles Dickens' many concerns was the roles assigned to women ...

  Citation × Citation Citation Abstract Copy Title: Women's voices : the emergence of female identity in Bleak House and Little Dorrit Author: Van Ras, Tamara L. Dedicated to recording, portraying, and indicting the social inequities that he witnessed in nineteenth century Victorian England, one of Charles Dickens' many concerns was the roles assigned to women both in the public and private spheres. The purpose of this thesis is to examine the narratives of Amy Dorrit and Miss Wade in Dickens' Little Dorrit and Esther Summerson in Bleak House to explore the ways in which each woman conforms to, subverts, or rejects her socially prescribed roles as she seeks to create her own identity while simultaneously complying to the duties and roles assigned her. This study focuses on the oral and written narratives of these women exploring their words, stories, and symbolic imagery. It also contextualizes their narratives while answering the critical question: How does individual identity emerge amid rigorously circumscribed social roles? Title: Women's voices : the emergence of female identity in Bleak House and Little Dorrit Author: Van Ras, Tamara L. Dedicated to recording, portraying, and indicting the social inequities that he witnessed in nineteenth century Victorian England, one of Charles Dickens' many concerns was the roles assigned to women both in the public and private spheres. The purpose of this thesis is to examine the narratives of Amy Dorrit and Miss Wade in Dickens' Little Dorrit and Esther Summerson in Bleak House to explore the ways in which each woman conforms to, subverts, or rejects her socially prescribed roles as she seeks to create her own identity while simultaneously complying to the duties and roles assigned her. This study focuses on the oral and written narratives of these women exploring their words, stories, and symbolic imagery. It also contextualizes their narratives while answering the critical question: How does individual identity emerge amid rigorously circumscribed social roles? Close

• 24. [Article] Improving Projections of Tidal Marsh Persistence under Climate Change with Remote Sensing and Site-Specific Data

  Tidal marshes are dynamic ecosystems that are threatened by climate change and sea-level rise. To characterize baseline condition and historic climate sensitivities, and improve projections into the future, ...

  Citation × Citation Citation Abstract Copy Title: Improving Projections of Tidal Marsh Persistence under Climate Change with Remote Sensing and Site-Specific Data Author: Buffington, Kevin John Tidal marshes are dynamic ecosystems that are threatened by climate change and sea-level rise. To characterize baseline condition and historic climate sensitivities, and improve projections into the future, new methods are required that integrate data from the field and remote sensing platforms. Marsh elevation response models can be calibrated with site-specific data to determine the vulnerability of a marsh to sea-level rise and help guide management decisions. Elevation models are sensitive to initial elevation, the rate of accretion, and aboveground biomass. The overarching goal of this dissertation was to develop techniques to improve these important model inputs and evaluate the range of spatial and temporal variation. Light detection and ranging (lidar) is an invaluable tool for collecting elevation data, however dense vegetation prevents the accurate measurement of the tidal marsh surface. In Chapter 2, I describe the development of a technique to calibrate lidar digital elevation models with survey elevation data using readily available multispectral aerial imagery from the National Agricultural Inventory Program (NAIP). Using survey elevation data across 17 Pacific Coast tidal marshes, I demonstrated the utility of the Lidar Elevation Adjustment with NDVI (LEAN) technique to account for the positive bias in lidar due to vegetation. LEAN reduced error from an average of 23.1 cm to 7.2 cm root mean squared error and removed the positive bias caused by vegetation. This increase in accuracy will facilitate more accurate assessments of current and future vulnerability to sea-level rise. The phenology of aboveground biomass in tidal marsh plants in relation to climate variation has not been explored in the Pacific Northwest (PNW). In Chapter 3 I explain how I leveraged the Landsat archive and cloud computing capabilities to assess how Tasseled Cap Greenness (TCG, a proxy for aboveground biomass) in three PNW tidal marshes has responded to recent variation in climate to characterize sensitivity to climate change. Through analysis of over 3700 Landsat images obtained from 1984-2015, I found increased annual precipitation resulted in a higher peak TCG, while warmer May temperatures resulted in an earlier day of peak TCG. These results also demonstrate how time-series analysis of remote sensing data can be used to examine the sensitivity of tidal marsh plants to climate variability and directional change. The range of variation in tidal marsh accretion rates has not been characterized across the PNW. For Chapter 4, I collected and analyzed twenty-two soil cores from eight estuaries to estimate historic accretion rates with radioisotope dating techniques and evaluated the amount and source of variation across estuaries. I found that tidal marshes across the PNW had accretion rates greater than the current rate of sea-level rise, ranging from 2.3 – 7.3 mm yr⁻¹. Using a watershed-scale analysis, I found that long-term average annual fluvial discharge was the top predictor of tidal marsh accretion rates. Additionally, I found that calibrating the Wetland Accretion Rate Model for Ecosystem Resilience (WARMER) with accretion rate data from nearby estuaries can result in uncertainties of up to 41% (50 cm) after 100 years. Finally, in Chapter 5, I demonstrate that a range of 62 cm of error is possible in WARMER models after a 100 year simulation when both uncorrected lidar and non-local accretion rates are used, fundamentally changing the interpretation of the results. Altogether, this dissertation illustrates the importance of collecting site-specific wetland vegetation and elevation data and demonstrates how lidar and multispectral remote sensing data can be leveraged to improve our understanding of how climate variability and change impacts coastal ecosystems. Title: Improving Projections of Tidal Marsh Persistence under Climate Change with Remote Sensing and Site-Specific Data Author: Buffington, Kevin John Tidal marshes are dynamic ecosystems that are threatened by climate change and sea-level rise. To characterize baseline condition and historic climate sensitivities, and improve projections into the future, new methods are required that integrate data from the field and remote sensing platforms. Marsh elevation response models can be calibrated with site-specific data to determine the vulnerability of a marsh to sea-level rise and help guide management decisions. Elevation models are sensitive to initial elevation, the rate of accretion, and aboveground biomass. The overarching goal of this dissertation was to develop techniques to improve these important model inputs and evaluate the range of spatial and temporal variation. Light detection and ranging (lidar) is an invaluable tool for collecting elevation data, however dense vegetation prevents the accurate measurement of the tidal marsh surface. In Chapter 2, I describe the development of a technique to calibrate lidar digital elevation models with survey elevation data using readily available multispectral aerial imagery from the National Agricultural Inventory Program (NAIP). Using survey elevation data across 17 Pacific Coast tidal marshes, I demonstrated the utility of the Lidar Elevation Adjustment with NDVI (LEAN) technique to account for the positive bias in lidar due to vegetation. LEAN reduced error from an average of 23.1 cm to 7.2 cm root mean squared error and removed the positive bias caused by vegetation. This increase in accuracy will facilitate more accurate assessments of current and future vulnerability to sea-level rise. The phenology of aboveground biomass in tidal marsh plants in relation to climate variation has not been explored in the Pacific Northwest (PNW). In Chapter 3 I explain how I leveraged the Landsat archive and cloud computing capabilities to assess how Tasseled Cap Greenness (TCG, a proxy for aboveground biomass) in three PNW tidal marshes has responded to recent variation in climate to characterize sensitivity to climate change. Through analysis of over 3700 Landsat images obtained from 1984-2015, I found increased annual precipitation resulted in a higher peak TCG, while warmer May temperatures resulted in an earlier day of peak TCG. These results also demonstrate how time-series analysis of remote sensing data can be used to examine the sensitivity of tidal marsh plants to climate variability and directional change. The range of variation in tidal marsh accretion rates has not been characterized across the PNW. For Chapter 4, I collected and analyzed twenty-two soil cores from eight estuaries to estimate historic accretion rates with radioisotope dating techniques and evaluated the amount and source of variation across estuaries. I found that tidal marshes across the PNW had accretion rates greater than the current rate of sea-level rise, ranging from 2.3 – 7.3 mm yr⁻¹. Using a watershed-scale analysis, I found that long-term average annual fluvial discharge was the top predictor of tidal marsh accretion rates. Additionally, I found that calibrating the Wetland Accretion Rate Model for Ecosystem Resilience (WARMER) with accretion rate data from nearby estuaries can result in uncertainties of up to 41% (50 cm) after 100 years. Finally, in Chapter 5, I demonstrate that a range of 62 cm of error is possible in WARMER models after a 100 year simulation when both uncorrected lidar and non-local accretion rates are used, fundamentally changing the interpretation of the results. Altogether, this dissertation illustrates the importance of collecting site-specific wetland vegetation and elevation data and demonstrates how lidar and multispectral remote sensing data can be leveraged to improve our understanding of how climate variability and change impacts coastal ecosystems. Close

• 25. [Article] Phase 1 scoping for Oregon orthoimagery portal application project completion report

  The Department of Administrative Services (DAS) and Oregon State University (OSU) are collaborating to develop an orthoimagery portal application to allow for the distribution of digital aerial imagery ...

  Citation × Citation Citation Abstract Copy Title: Phase 1 scoping for Oregon orthoimagery portal application project completion report Author: Institute for Natural Resources, Oregon State University Libraries The Department of Administrative Services (DAS) and Oregon State University (OSU) are collaborating to develop an orthoimagery portal application to allow for the distribution of digital aerial imagery for the State of Oregon. The near-term objective of this project is to develop an Imagery Portal that serves the 2005 half-meter orthoimagery that the State has obtained from the National Agriculture Imagery Program (NAIP) and other aerial imagery datasets. The targeted primary users for the imagery portal are Federal, State, and local agencies and institutions of higher education. Secondary users include the general public. Title: Phase 1 scoping for Oregon orthoimagery portal application project completion report Author: Institute for Natural Resources, Oregon State University Libraries The Department of Administrative Services (DAS) and Oregon State University (OSU) are collaborating to develop an orthoimagery portal application to allow for the distribution of digital aerial imagery for the State of Oregon. The near-term objective of this project is to develop an Imagery Portal that serves the 2005 half-meter orthoimagery that the State has obtained from the National Agriculture Imagery Program (NAIP) and other aerial imagery datasets. The targeted primary users for the imagery portal are Federal, State, and local agencies and institutions of higher education. Secondary users include the general public. Close

• 26. [Article] Waning magmatic activity along the Southern Explorer Ridge revealed through fault restoration of rift topography

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. American Geophysical Union – Geochemistry, Geophysics, Geosystems - G³ This is the ...

  Citation × Citation Citation Abstract Copy Title: Waning magmatic activity along the Southern Explorer Ridge revealed through fault restoration of rift topography Author: Chadwick Jr., W. W., Tivey, M. A., Deschamps, A., Embley, R. W. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. American Geophysical Union – Geochemistry, Geophysics, Geosystems - G³ This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/gc/. Title: Waning magmatic activity along the Southern Explorer Ridge revealed through fault restoration of rift topography Author: Chadwick Jr., W. W., Tivey, M. A., Deschamps, A., Embley, R. W. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. American Geophysical Union – Geochemistry, Geophysics, Geosystems - G³ This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/gc/. Close

• 27. [Article] Planning Under Uncertainty for Unmanned Aerial Vehicles

  Unmanned aerial vehicle (UAV) technology has grown out of traditional research and military applications and has captivated the commercial and consumer markets, showing the ability to perform a spectrum ...

  Citation × Citation Citation Abstract Copy Title: Planning Under Uncertainty for Unmanned Aerial Vehicles Author: Skeele, Ryan Unmanned aerial vehicle (UAV) technology has grown out of traditional research and military applications and has captivated the commercial and consumer markets, showing the ability to perform a spectrum of autonomous functions. This technology has the capability of saving lives in search and rescue, fighting wildfires in environmental monitoring, and delivering time dependent medicine in package delivery. These examples demonstrate the potential impact this technology will have on our society. However, it is evident how sensitive UAVs are to the uncertainty of the physical world. In order to properly achieve the full potential of UAVs in these markets, robust and efficient planning algorithms are needed. This thesis addresses the challenge of planning under uncertainty for UAVs. We develop a suite of algorithms that are robust to changes in the environment and build on the key areas of research needed for utilizing UAVs in a commercial setting. Throughout this research three main components emerged: monitoring targets in dynamic environments, exploration with unreliable communication, and risk-aware path planning. We use a realistic fire simulation to test persistent monitoring in an uncertain environment. The fire is generated using the standard program for modeling wildfire, FARSITE. This model was used to validate a weighted-greedy approach to monitoring clustered points of interest (POIs) over traditional methods of tracking a fire front. We implemented the algorithm on a commercial UAV to demonstrate the deployment capability. Dynamic monitoring has limited potential if if coordinated planning is fallible to uncertainty in the world. Uncertain communication can cause critical failures in coordinated planning algorithms. We develop a method for coordinated exploration of a multi-UAV team with unreliable communication and limited battery life. Our results show that the proposed algorithm, which leverages meeting, sacrificing, and relaying behavior, increases the percentage of the environment explored over a frontier-based exploration strategy by up to 18%. We test on teams of up to 8 simulated UAVs and 2 real UAVs able to cope with communication loss and still report improved gains. We demonstrate this work with a pair of custom UAVs in an indoor office environment. We introduce a novel approach to incorporating and addressing uncertainty in planning problems. The proposed Risk-Aware Graph Search (RAGS) algorithm combines traditional deterministic search techniques with risk-aware planning. RAGS is able to trade off the number of future path options, as well as the mean and variance of the associated path cost distributions to make online edge traversal decisions that minimize the risk of executing a high-cost path. The algorithm is compared against existing graphsearch techniques on a set of graphs with randomly assigned edge costs, as well as over a set of graphs with transition costs generated from satellite imagery data. In all cases, RAGS is shown to reduce the probability of executing high-cost paths over A*, D* and a greedy planning approach. High level planning algorithms can be brittle in dynamic conditions where the environment is not modeled perfectly. In developing planners for uncertainty we ensure UAVs will be able to operate in conditions outside the scope of prior techniques. We address the need for robustness in robotic monitoring, coordination, and path planning tasks. Each of the three methods introduced were tested in simulated and real environments, and the results show improvement over traditional algorithms. Title: Planning Under Uncertainty for Unmanned Aerial Vehicles Author: Skeele, Ryan Unmanned aerial vehicle (UAV) technology has grown out of traditional research and military applications and has captivated the commercial and consumer markets, showing the ability to perform a spectrum of autonomous functions. This technology has the capability of saving lives in search and rescue, fighting wildfires in environmental monitoring, and delivering time dependent medicine in package delivery. These examples demonstrate the potential impact this technology will have on our society. However, it is evident how sensitive UAVs are to the uncertainty of the physical world. In order to properly achieve the full potential of UAVs in these markets, robust and efficient planning algorithms are needed. This thesis addresses the challenge of planning under uncertainty for UAVs. We develop a suite of algorithms that are robust to changes in the environment and build on the key areas of research needed for utilizing UAVs in a commercial setting. Throughout this research three main components emerged: monitoring targets in dynamic environments, exploration with unreliable communication, and risk-aware path planning. We use a realistic fire simulation to test persistent monitoring in an uncertain environment. The fire is generated using the standard program for modeling wildfire, FARSITE. This model was used to validate a weighted-greedy approach to monitoring clustered points of interest (POIs) over traditional methods of tracking a fire front. We implemented the algorithm on a commercial UAV to demonstrate the deployment capability. Dynamic monitoring has limited potential if if coordinated planning is fallible to uncertainty in the world. Uncertain communication can cause critical failures in coordinated planning algorithms. We develop a method for coordinated exploration of a multi-UAV team with unreliable communication and limited battery life. Our results show that the proposed algorithm, which leverages meeting, sacrificing, and relaying behavior, increases the percentage of the environment explored over a frontier-based exploration strategy by up to 18%. We test on teams of up to 8 simulated UAVs and 2 real UAVs able to cope with communication loss and still report improved gains. We demonstrate this work with a pair of custom UAVs in an indoor office environment. We introduce a novel approach to incorporating and addressing uncertainty in planning problems. The proposed Risk-Aware Graph Search (RAGS) algorithm combines traditional deterministic search techniques with risk-aware planning. RAGS is able to trade off the number of future path options, as well as the mean and variance of the associated path cost distributions to make online edge traversal decisions that minimize the risk of executing a high-cost path. The algorithm is compared against existing graphsearch techniques on a set of graphs with randomly assigned edge costs, as well as over a set of graphs with transition costs generated from satellite imagery data. In all cases, RAGS is shown to reduce the probability of executing high-cost paths over A*, D* and a greedy planning approach. High level planning algorithms can be brittle in dynamic conditions where the environment is not modeled perfectly. In developing planners for uncertainty we ensure UAVs will be able to operate in conditions outside the scope of prior techniques. We address the need for robustness in robotic monitoring, coordination, and path planning tasks. Each of the three methods introduced were tested in simulated and real environments, and the results show improvement over traditional algorithms. Close

• 28. [Article] "Style upon style": The Handmaid's Tale as a palimpsest of genres

  This thesis undertakes an examination of Margaret Atwood’s 1985 novel, The Handmaid’s Tale, as a layering of genres. A futuristic dystopia that imagines late twentieth-century America as having fallen ...

  Citation × Citation Citation Abstract Copy Title: "Style upon style": The Handmaid's Tale as a palimpsest of genres Author: Boulware, Taylor J. This thesis undertakes an examination of Margaret Atwood’s 1985 novel, The Handmaid’s Tale, as a layering of genres. A futuristic dystopia that imagines late twentieth-century America as having fallen into neo-Puritanism and totalitarianism following widespread infertility and violence, The Handmaid’s Tale invites contemplation of various forms of fundamentalism, radicalism, and sexual politics. Atwood’s use of palimpsestic imagery to convey a layered experience of time extends to the generic complexity of The Handmaid’s Tale. Using the image of the palimpsest as the controlling metaphor, I survey the ways in which the novel can be read as an historical novel, satire, and postmodern text, exploring the ways in which the novel embodies and extends the defining characteristics of each genre. These genres share the common trait of functioning as social commentary. Thus, an examination of the novel’s layering of genres works to provide greater insights into the ways in which Atwood is interrogating the mid-1980s cultural milieu to which she was responding and from which she was writing. Title: "Style upon style": The Handmaid's Tale as a palimpsest of genres Author: Boulware, Taylor J. This thesis undertakes an examination of Margaret Atwood’s 1985 novel, The Handmaid’s Tale, as a layering of genres. A futuristic dystopia that imagines late twentieth-century America as having fallen into neo-Puritanism and totalitarianism following widespread infertility and violence, The Handmaid’s Tale invites contemplation of various forms of fundamentalism, radicalism, and sexual politics. Atwood’s use of palimpsestic imagery to convey a layered experience of time extends to the generic complexity of The Handmaid’s Tale. Using the image of the palimpsest as the controlling metaphor, I survey the ways in which the novel can be read as an historical novel, satire, and postmodern text, exploring the ways in which the novel embodies and extends the defining characteristics of each genre. These genres share the common trait of functioning as social commentary. Thus, an examination of the novel’s layering of genres works to provide greater insights into the ways in which Atwood is interrogating the mid-1980s cultural milieu to which she was responding and from which she was writing. Close

• 29. [Article] Urban development in coastal Oregon : discrete-choice estimation with spatial autocorrelation

  Development along the Oregon coast is continuing in areas that are known to be hazardous, in spite of strict zoning and other laws. The coast commonly sees erosion that can wash away cliffs and undermine ...

  Citation × Citation Citation Abstract Copy Title: Urban development in coastal Oregon : discrete-choice estimation with spatial autocorrelation Author: Todd, Maribeth Development along the Oregon coast is continuing in areas that are known to be hazardous, in spite of strict zoning and other laws. The coast commonly sees erosion that can wash away cliffs and undermine structures as well as accretion that can bury houses in sand. However the much more acute risk is the potential for a tsunami triggered by an earthquake in the ocean. This paper examines the factors influencing development along the Oregon coast using satellite imagery and other spatial data. An econometric model for land use change at the pixel level is developed. The scale at which the data (satellite imagery) are collected is different from the scale at which development occurs, leading to spatial correlation among pixels that are geographically close to each other. Estimating a standard probit model in this case leads to parameter estimates that are inconsistent. Incorporating a spatial lag of the dependent variable will account for the spatial autocorrelation but makes maximum likelihood estimation nearly impossible so a Bayesian approach is used instead. A Gibb's sampling algorithm is implemented to estimate the conditional distribution of each parameter in the model, from which parameter estimates can be derived. The Bayesian spatial probit estimation is very computationally intensive however the results indicate that the spatial lag is a crucial part of the model. This approach also allows projections of the spatial pattern of future development, unlike estimation methods that sample the data to remove autocorrelation among observations. The spatial lag model is then used to project future development patterns in several regions along the Oregon coast and explore potential applications of this projection model. In particular, predicted development patterns in the tsunami hazard zone are examined in the Waldport area, on the central coast of Oregon. Title: Urban development in coastal Oregon : discrete-choice estimation with spatial autocorrelation Author: Todd, Maribeth Development along the Oregon coast is continuing in areas that are known to be hazardous, in spite of strict zoning and other laws. The coast commonly sees erosion that can wash away cliffs and undermine structures as well as accretion that can bury houses in sand. However the much more acute risk is the potential for a tsunami triggered by an earthquake in the ocean. This paper examines the factors influencing development along the Oregon coast using satellite imagery and other spatial data. An econometric model for land use change at the pixel level is developed. The scale at which the data (satellite imagery) are collected is different from the scale at which development occurs, leading to spatial correlation among pixels that are geographically close to each other. Estimating a standard probit model in this case leads to parameter estimates that are inconsistent. Incorporating a spatial lag of the dependent variable will account for the spatial autocorrelation but makes maximum likelihood estimation nearly impossible so a Bayesian approach is used instead. A Gibb's sampling algorithm is implemented to estimate the conditional distribution of each parameter in the model, from which parameter estimates can be derived. The Bayesian spatial probit estimation is very computationally intensive however the results indicate that the spatial lag is a crucial part of the model. This approach also allows projections of the spatial pattern of future development, unlike estimation methods that sample the data to remove autocorrelation among observations. The spatial lag model is then used to project future development patterns in several regions along the Oregon coast and explore potential applications of this projection model. In particular, predicted development patterns in the tsunami hazard zone are examined in the Waldport area, on the central coast of Oregon. Close

• 30. [Article] Landsat-based monitoring of annual wetland change in the main-stem Willamette River floodplain of Oregon, USA from 1972 to 2012

  Despite holding substantial ecological value, wetlands in the United States have experienced a significant decline in both area and function over the past century with the majority of freshwater wetland ...

  Citation × Citation Citation Abstract Copy Title: Landsat-based monitoring of annual wetland change in the main-stem Willamette River floodplain of Oregon, USA from 1972 to 2012 Author: Fickas, Kate, Colleen Despite holding substantial ecological value, wetlands in the United States have experienced a significant decline in both area and function over the past century with the majority of freshwater wetland loss attributed to agricultural conversion. Agriculture is the second largest industry in the State of Oregon and the State places substantial emphasis in its land use planning goals on the preservation of agricultural land. Oregon’s Willamette Valley accounts for the majority of agricultural output with 53% of the valley bottom classified as agricultural land. Additionally, the valley houses 70% of the state's population. The valley was once comprised of extensive wet prairies and abundant riparian forests along the Willamette River floodplain, but native ecosystems have been reduced to a fraction of their original distribution since Euro-American settlement in the mid 1800s. The few wetlands that remain are at high risk to loss and degradation from agricultural activity. Following national wetland conservation policies, Oregon has since attempted to monitor and regulate losses due to disturbance and modification of the State's remaining wetlands through a "no-net-loss" policy aiming to decrease wetland losses and replace disturbed wetlands through mitigation. The National Wetlands Inventory (NWI) was designed to produce detailed maps and status reports of the characteristics and extent of the nation's wetlands and help determine the efficacy of no-net-loss policy implementation on the nation’s wetlands. In some cases, the NWI has been found to have low categorical and spatial accuracy and coarse temporal resolution, with some maps over two decades old. Although Landsat satellite imagery was originally found to lack the needed spatial resolution for classification detail and wetness designation that aerial photography provided, Landsat has 40 years of freely available, high quality annual imagery and should be explored for use in annual wetland change detection. Our objectives were to: (1) Quantify and characterize spatial and ecological trends in annual wetland change through gain, loss, and conversion in the Willamette Valley; (2) Evaluate the effect of the no-net-loss federal wetland conservation policy change enacted in 1990 on trends in net wetland area; and (3) Describe a new methodology that reaches back through the over 40-year Landsat archive to map fine scale wetland and related land-use changes from 1972-2012. We used annual Landsat MSS and TM/ETM+ images from 1972 to 2012 to manually interpret loss, gain, and type conversion of wetland area in the two-year inundation floodplain of the Main-Stem Willamette River using TimeSync, Google Earth, and ArcMap. By creating Tasseled Cap Brightness, Greenness, and Wetness indices for MSS data that visually match TM/ETM+ Tasseled Cap images, we were able to construct a complete and consistent annual time series and utilize the entire Landsat archive. Additionally, with an extended time series, we were able to compare trends of annual net change in wetland area before and after the no-net-loss policy established under Section 404 of the Clean Water Act in 1990. We found that wetlands experienced annual loss, gain, and type conversion across the entire study period. Vegetated wetlands (emergent and riparian wetlands) experienced a 314 ha net loss of wetland area across the 40 year study period whereas non-vegetated wetlands (lacustrine and riverine wetlands) experienced a 393 ha net gain. All wetland types combined saw a 79 ha net increase in wetland area across the full study period. The majority of both gain and loss in the study area was attributed to and from agricultural conversion followed by urban land use. Time series analysis of the rate of change of net wetland area was calculated using the Theil-Sen (TS) Slope estimate analysis. For annual change of wetland area before and after 1990 no-net-loss policy implementations, the rate of annual wetland area lost slowed for riparian wetlands and reversed into trends of annual net gain in area of emergent wetlands. The rate of annual net area gained for lacustrine wetlands was slowed post-policy. Accuracy assessment of land use change polygons in the field was only able to capture 12% of our interpretations due to access restrictions associated with private land. In spite of a low sample size (n=45), overall accuracy of land use classification through wetland change polygons was at 80%. This accuracy increased to 91.1% when land use classes were aggregated to either wetland or upland categories, indicating that our methodology was more accurate at distinguishing between general upland and wetland than finer categorical classes. Title: Landsat-based monitoring of annual wetland change in the main-stem Willamette River floodplain of Oregon, USA from 1972 to 2012 Author: Fickas, Kate, Colleen Despite holding substantial ecological value, wetlands in the United States have experienced a significant decline in both area and function over the past century with the majority of freshwater wetland loss attributed to agricultural conversion. Agriculture is the second largest industry in the State of Oregon and the State places substantial emphasis in its land use planning goals on the preservation of agricultural land. Oregon’s Willamette Valley accounts for the majority of agricultural output with 53% of the valley bottom classified as agricultural land. Additionally, the valley houses 70% of the state's population. The valley was once comprised of extensive wet prairies and abundant riparian forests along the Willamette River floodplain, but native ecosystems have been reduced to a fraction of their original distribution since Euro-American settlement in the mid 1800s. The few wetlands that remain are at high risk to loss and degradation from agricultural activity. Following national wetland conservation policies, Oregon has since attempted to monitor and regulate losses due to disturbance and modification of the State's remaining wetlands through a "no-net-loss" policy aiming to decrease wetland losses and replace disturbed wetlands through mitigation. The National Wetlands Inventory (NWI) was designed to produce detailed maps and status reports of the characteristics and extent of the nation's wetlands and help determine the efficacy of no-net-loss policy implementation on the nation’s wetlands. In some cases, the NWI has been found to have low categorical and spatial accuracy and coarse temporal resolution, with some maps over two decades old. Although Landsat satellite imagery was originally found to lack the needed spatial resolution for classification detail and wetness designation that aerial photography provided, Landsat has 40 years of freely available, high quality annual imagery and should be explored for use in annual wetland change detection. Our objectives were to: (1) Quantify and characterize spatial and ecological trends in annual wetland change through gain, loss, and conversion in the Willamette Valley; (2) Evaluate the effect of the no-net-loss federal wetland conservation policy change enacted in 1990 on trends in net wetland area; and (3) Describe a new methodology that reaches back through the over 40-year Landsat archive to map fine scale wetland and related land-use changes from 1972-2012. We used annual Landsat MSS and TM/ETM+ images from 1972 to 2012 to manually interpret loss, gain, and type conversion of wetland area in the two-year inundation floodplain of the Main-Stem Willamette River using TimeSync, Google Earth, and ArcMap. By creating Tasseled Cap Brightness, Greenness, and Wetness indices for MSS data that visually match TM/ETM+ Tasseled Cap images, we were able to construct a complete and consistent annual time series and utilize the entire Landsat archive. Additionally, with an extended time series, we were able to compare trends of annual net change in wetland area before and after the no-net-loss policy established under Section 404 of the Clean Water Act in 1990. We found that wetlands experienced annual loss, gain, and type conversion across the entire study period. Vegetated wetlands (emergent and riparian wetlands) experienced a 314 ha net loss of wetland area across the 40 year study period whereas non-vegetated wetlands (lacustrine and riverine wetlands) experienced a 393 ha net gain. All wetland types combined saw a 79 ha net increase in wetland area across the full study period. The majority of both gain and loss in the study area was attributed to and from agricultural conversion followed by urban land use. Time series analysis of the rate of change of net wetland area was calculated using the Theil-Sen (TS) Slope estimate analysis. For annual change of wetland area before and after 1990 no-net-loss policy implementations, the rate of annual wetland area lost slowed for riparian wetlands and reversed into trends of annual net gain in area of emergent wetlands. The rate of annual net area gained for lacustrine wetlands was slowed post-policy. Accuracy assessment of land use change polygons in the field was only able to capture 12% of our interpretations due to access restrictions associated with private land. In spite of a low sample size (n=45), overall accuracy of land use classification through wetland change polygons was at 80%. This accuracy increased to 91.1% when land use classes were aggregated to either wetland or upland categories, indicating that our methodology was more accurate at distinguishing between general upland and wetland than finer categorical classes. Close