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2021

Dissertations and Theses

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Articles 1 - 13 of 13

Full-Text Articles in Geography

Assessment Of Vertical Accuracy From Uav-Lidar And Structure From Motion Point Clouds In Floodplain Terrain Mapping, Andrew Muller Dec 2021

Assessment Of Vertical Accuracy From Uav-Lidar And Structure From Motion Point Clouds In Floodplain Terrain Mapping, Andrew Muller

Dissertations and Theses

Remote sensing technologies are being applied to a variety of uses because of the increase in access to various products (digital sensors, UAVs, software) and its ability to model relatively large areas in a short amount of time. While these new technologies are beginning to be adopted, validation of their merit in floodplain terrain mapping is lacking. The main goal of this study is to evaluate the vertical accuracy of digital elevation models (DEMs) generated with UAV-based LiDAR and Structure from Motion (SfM), also known as photographic LiDAR or PhoDAR. Airborne (manned aircraft) LiDAR has been applied to river research …


Modeling Environmental Factors Related To Drought-Induced Tree Mortality Based On Lidar And Hyperspectral Imagery, Lauren Nicole Sharwood Nov 2021

Modeling Environmental Factors Related To Drought-Induced Tree Mortality Based On Lidar And Hyperspectral Imagery, Lauren Nicole Sharwood

Dissertations and Theses

Climate change is projected to bring more frequent and prolonged droughts, causing widespread forest die-off. Identifying tree mortality over large spatial extents in response to the most recent California drought will help forest managers and conservationists understand where there may be a greater likelihood of future die-offs. In order to find more at-risk areas, this study evaluated how interacting site-specific topographic, climate, substrate, and stand characteristics mediated tree mortality in the Central Sierra Nevada during the 2012-2016 drought. The author used lidar and hyperspectral imagery provided by the National Ecological Observatory Network to identify individual dead trees using the Random …


Mapping The Publics: The Production Of Spatial Knowledge And Public Interest, Paul Thomas Manson Nov 2021

Mapping The Publics: The Production Of Spatial Knowledge And Public Interest, Paul Thomas Manson

Dissertations and Theses

Over the past decades, calls for comprehensively managing and planning ocean resources have emerged internationally and within the United States. Central to these calls is a drive to expand coastal and marine spatial planning with a particular focus on technologically mediated public involvement. These new public involvement technologies aim, more quickly and thoroughly, to solicit and analyze public values and existing uses of the coastal and marine environments. One particular technological innovation is the use of participatory geographic information systems (PGIS). These new tools allow for stakeholders, members of the public, and planning entities to collect, visualize, and interact with …


My Mountain, Your Mountain, Our Mountain: Incorporating Emotional And Sensory Experiences In Mapping Sense Of Place In Mount Hood National Forest, Alicia Ranae Milligan Sep 2021

My Mountain, Your Mountain, Our Mountain: Incorporating Emotional And Sensory Experiences In Mapping Sense Of Place In Mount Hood National Forest, Alicia Ranae Milligan

Dissertations and Theses

Understanding the complex connections humans have with landscapes is necessary for successful land management and planning practices. Only within the last few decades has mapping the values of forest users been used to produce data that can be incorporated into forest planning as a means to better understand social and environmental dynamics. This research used sense of place web mapping coupled with interviews to understand forest users' emotional and sensory experiences within the Mount Hood National Forest and to improve future sense of place mapping research. Two objectives were addressed in this research: 1) develop a typology of individuals' emotions …


Forest Fire Effects On The Temporal Variability Of Landscape Snow Albedo Relative To Burn Severity, Max Gersh Sep 2021

Forest Fire Effects On The Temporal Variability Of Landscape Snow Albedo Relative To Burn Severity, Max Gersh

Dissertations and Theses

Snow-water storage is decreasing, while forest fires are increasing in duration, size, frequency, and intensity, due to climate change. Most forest fires occur in the seasonal snow zone, altering snow mass and energy balance for many years following fire. Following forest fires, Surface snow albedo (SSA) decreases, as light absorbing particles (LAP), particularly black carbon (BC) produced in forest fires get deposited throughout the snowpack, altering snowpack energy balance driving earlier snowmelt in burned forests. While SSA decreases, landscape snow albedo (LSA) increases following fire, as more of the snow-covered surface becomes visible beneath the burned forest canopy, brightening the …


Climate Model Evaluation Of Atmospheric Rivers Over The Contiguous United States, Ilan González-Hirshfeld Jul 2021

Climate Model Evaluation Of Atmospheric Rivers Over The Contiguous United States, Ilan González-Hirshfeld

Dissertations and Theses

Atmospheric rivers (ARs)--long corridors of intense atmospheric water vapor transport--significantly influence the hydrologic cycle and regional hydrometeorological extremes across the contiguous United States (CONUS). Ongoing and future climate change may alter AR characteristics and impacts, making confident climate model projections of future change, especially at regional scales, of critical importance. In order to better constrain uncertainty in such projections of future change, we perform a comprehensive climate model evaluation of AR climatology over the CONUS. Using an established AR detection algorithm, we evaluate the representation of ARs in historical simulations (1984-2013) from a suite of models participating in the sixth …


Relationship Between Image Spectroscopy Spatial Resolution And Crown Level Tree Species Classification Accuracy, Andrew Richard Fritter Jul 2021

Relationship Between Image Spectroscopy Spatial Resolution And Crown Level Tree Species Classification Accuracy, Andrew Richard Fritter

Dissertations and Theses

Hyperspectral imagery has become a common remote sensing data type used in tree species classifications because of its rich spectral signals that allow the detection of the variations in canopy reflectance. While high spatial resolution hyperspectral imagery provides fine spatial resolution for discerning surface objects, it has the inherent drawbacks of expensive acquisition costs, large data sizes, and can be computationally taxing to use. This study attempts to determine a relationship between crown level tree species classification accuracy and hyperspectral spatial resolution. Future tree species classification projects can make use of this relationship by targeting a spatial resolution that best …


Projections Of Large-Scale Atmospheric Circulation Patterns And Associated Temperature And Precipitation Over The Pacific Northwest Using Cmip6 Models, Graham Patrick Taylor Jul 2021

Projections Of Large-Scale Atmospheric Circulation Patterns And Associated Temperature And Precipitation Over The Pacific Northwest Using Cmip6 Models, Graham Patrick Taylor

Dissertations and Theses

Projections of 500 hPa geopotential height (Z500) patterns over the Pacific Northwest of North America and their associated surface temperature, precipitation, and frequency of occurrence are assessed using models from the 6th phase of the Coupled Model Intercomparison Project (CMIP6). The self-organizing maps approach is applied to reanalysis data from the Modern-Era Retrospective Analysis for Research and Applications, version-2 (MERRA-2) to cluster daily Z500 anomalies into 12 representative patterns that span the range of historical circulation patterns. CMIP6 data for daily Z500 anomalies are mapped to each node for historical and end of century global warming experiments, and the resulting …


Rowing Concerns: Collaborative Governance And Stakeholder Determination In The Central Oregon's Deschutes Basin, Noel Vineyard Jul 2021

Rowing Concerns: Collaborative Governance And Stakeholder Determination In The Central Oregon's Deschutes Basin, Noel Vineyard

Dissertations and Theses

In 2019, a coalition of irrigation districts in central Oregon's Deschutes Basin submitted the Deschutes Basin Habitat Conservation Plan to the US Department of Fish and Wildlife. This Habitat Conservation Plan purported to have been constructed through a collaborative governance structure between the irrigation districts and various community stakeholders who all had interests in basin management, however segments of the Basin's river recreation community began to raise concerns that their voices were not included. The purpose of this research was to investigate how stakeholder status in the Deschutes Basin is created through collaborative water governance processes like development of the …


Portland Urban Coyote Project: A Review Of Citizen Science's Utility For Researching Urban Canids And The Human Environment, Keith David Vanderbrooke Apr 2021

Portland Urban Coyote Project: A Review Of Citizen Science's Utility For Researching Urban Canids And The Human Environment, Keith David Vanderbrooke

Dissertations and Theses

The Portland Urban Coyote Project (PUCP) is a citizen science project that allows community members to upload coyote (Canis latrans) sighting data to a database that is used to create a public web map; contributors often add observations as well. I analyzed one year of PUCP comment data in order to assess the utility of the citizen science methods used by PUCP for urban carnivore research. I code and summarize findings from PUCP's data, compare the extracted data to other research studies of urban coyote from other regions, and find that results from this analysis supports conclusions made …


Climatic Controls On The Kinematics Of The Hooskanaden Landslide, Curry County, Oregon, Kara Kingen Apr 2021

Climatic Controls On The Kinematics Of The Hooskanaden Landslide, Curry County, Oregon, Kara Kingen

Dissertations and Theses

Slow-moving earthflows represent major sources of sediment transport and erosion and are problematic for the management of critical infrastructure. The Hooskanaden Landslide -- a slow-moving earthflow on the southwest coast of Oregon -- crosses US Highway 101 and has been a site of continued interest to the Oregon Department of Transportation (ODOT) due to the weak lithology, erosive environment, and recurrent surge behavior (every ~15 years). Past surges, including the most recent (2019), have occurred during the winter, suggesting that velocity changes are predominantly controlled by climatic inputs. To examine the response of the Hooskanaden Landslide to seasonal and other …


Evaluation Of Manual And Semi-Automated Deep-Seated Landslide Inventory Processes: Willapa Hills, Washington, Tiffany E. Justice Mar 2021

Evaluation Of Manual And Semi-Automated Deep-Seated Landslide Inventory Processes: Willapa Hills, Washington, Tiffany E. Justice

Dissertations and Theses

Recent advances in remote sensing data and technology have allowed for computational models to be designed that successfully extract landforms from the landscape. The goal of this work is to create one such semi-automated model to extract deep-seated landslides located in complex geomorphic terrain. This is accomplished using geographic object-based image analysis (GEOBIA) techniques, considered by leaders in the field of image analysis to have an advantage over traditional automated classification methods. GEOBIA methods can mimic human visual interpretation by including more characteristic features used to assess the relationship between image data and the ground surface such as color reflectance …


Reassessing The Ranging Behavior Of Black-And-White Ruffed Lemurs (Varecia Variegata) In Ranomafana National Park, Madagascar, Jelisa R. Oliveras Jan 2021

Reassessing The Ranging Behavior Of Black-And-White Ruffed Lemurs (Varecia Variegata) In Ranomafana National Park, Madagascar, Jelisa R. Oliveras

Dissertations and Theses

This study investigates black-and-white ruffed lemur (Varecia variegata) space use and movement using autocorrelated kernel density estimation (AKDE), a new methodology available from the continuous-time movement model (ctmm) package in R. Data were collected from 24 adults and subadults (10 males, 11 females, 3 subadult males) living in two adjacent V. variegata communities at Mangevo bush camp in Ranomafana National Park, Madagascar (RNP) for 11 months (February – December 2008) to estimate annual and seasonal patterns of individual and community-level range use. Autocorrelated kernel density estimates generated in this study are compared to earlier kernel density estimates from …