Social and Behavioral Sciences Commons^™

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 …

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

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 …

Environmental And Spatial Factors Affecting Surface Water Quality In A Himalayan Watershed, Central Nepal, Janardan Mainali, Heejun Chang

Geography Faculty Publications and Presentations

Various spatial interrelationships among sampling stations are not well explored in the spatial modeling of water quality literature. This research explores the relationship between water quality and various social, demographic, and topographic factors in an urbanizing watershed of Nepal with a comparison of different connectivity matrices to conceptualize spatial interrelationships. We collected electrical conductivity and dissolved oxygen data from surface water bodies using a handheld probe and used the data to establish relationships with land use, topography, and population density-based explanatory variables at both watershed and 100-m buffer scales. The linear regression model was compared with different eigenvector-based spatial filtering …

Pre-Emptive Detection Of Mature Pine Drought Stress Using Multispectral Aerial Imagery, Nancy Grulke, Jason Maxfield, Phillip Riggan, Charlie Schrader-Patton

Biology Faculty Publications and Presentations

Drought, ozone (O₃), and nitrogen deposition (N) alter foliar pigments and tree crown structure that may be remotely detectable. Remote sensing tools are needed that pre-emptively identify trees susceptible to environmental stresses could inform forest managers in advance of tree mortality risk. Jeffrey pine, a component of the economically important and widespread western yellow pine in North America was investigated in the southern Sierra Nevada. Transpiration of mature trees differed by 20% between microsites with adequate (mesic (M)) vs. limited (xeric (X)) water availability as described in a previous study. In this study, in-the-crown morphological traits (needle chlorosis, …

Lidar Predictive Modeling Of Kalapuya Mound Sites In The Calapooia Watershed, Oregon, Tia Rachelle Cody

Dissertations and Theses

Archaeologists grapple with the problematic nature of archaeological discovery. Certain types of sites are difficult to see even in the best environmental conditions (e.g., low-density lithic scatters) and performing traditional archaeological survey is challenging in some environments, such as the dense temperate rain forests of the Pacific Northwest. Archaeologists need another method of survey to assess large areas and overcome environmental and archaeological barriers to site discovery in regions like the Pacific Northwest. LiDAR (light detection and ranging) technology, a method for digitally clearing away swaths of vegetation and surveying the landscape, is one possible solution to some of these …

Modeling Acoustic Scattering From The Seabed Using Transport Theory, Jorge Quijano, Lisa M. Zurk

Electrical and Computer Engineering Faculty Publications and Presentations

Radiative Transfer (RT) theory has established itself as an important tool for electromagnetic remote sensing in parallel plane geometries with random distributions of scatterers, and most recently it has also been proposed as a model for the propagation of elastic waves in layered ocean sediments. In this work the capabilities of this model are illustrated, as the RT method is used to predict backscattering strength from laboratory models of random media. The RT model is characterized by its flexibility on accommodating scatterers in a broad variety of sizes, shapes, and acoustic contrast relative to the background media. Additionally, this formulation …

Comparing Twenty-Four Years Of Forest Change In Two Communities Of Mexico's Meseta PuréPecha Using Multi-Spectral Satellite Imagery, Kevin Scott Martin

Dissertations and Theses

The Meseta Purépecha, a volcanic plateau in the Mexican state of Michoacan, is home to one of the most species-rich pine forests in the world. Recent increases in demand for forest products has put added pressure on these resources. Though existing research has suggested significant deforestation in the Meseta, there is little information identifying specific areas of decline. This study focuses on two indigenous communities in the Meseta--Pichátaro and Sevina. Both communities have long relied on wood as an economic resource. However, the two communities have reacted differently to increased demand for forest resources. The purpose of this study is …

Satellite Remote Sensing For Measuring The Urban Forest Of Portland, Oregon, A. Paul Newman

Dissertations and Theses

Digital pattern recognition methods were used to produce two maps of urban vegetation from LANDSAT Thematic Mapper for the City of Portland, Oregon. The image was acquired on July 7, 1991 and the spectral bands used were 2, 4, 5 and a ratio of 3 and 4. The two maps represent vegetation amount and vegetation type.

Due to the extreme heterogeneous nature of the urban environment, these maps were developed using techniques to reduce and manage the amount of spectral variation. This included purging non-vegetated cells from the multispectral image, and then stratifying the image into "spectral subdivisions" using tools …