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Yolov4_Cspbi: Enhanced Land Target Detection Model, Lirong Yin, Lei Wang, Jianqiang Li, Siyu Lu, Jiawei Tian, Zhengtong Yin, Shan Liu, Wenfeng Zheng Sep 2023

Yolov4_Cspbi: Enhanced Land Target Detection Model, Lirong Yin, Lei Wang, Jianqiang Li, Siyu Lu, Jiawei Tian, Zhengtong Yin, Shan Liu, Wenfeng Zheng

Faculty Publications

The identification of small land targets in remote sensing imagery has emerged as a significant research objective. Despite significant advancements in object detection strategies based on deep learning for visible remote sensing images, the performance of detecting a small and densely distributed number of small targets remains suboptimal. To address this issue, this study introduces an improved model named YOLOV4_CPSBi, based on the YOLOV4 architecture, specifically designed to enhance the detection capability of small land targets in remote sensing imagery. The proposed model enhances the traditional CSPNet by redefining its channel partitioning and integrating this enhanced structure into the neck …

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Settling Into Inequality: Resettled Afghans In The Washington Dc Metro Area, Harry Frey Sep 2023

Settling Into Inequality: Resettled Afghans In The Washington Dc Metro Area, Harry Frey

Dissertations, Theses, and Capstone Projects

Since the Taliban returned to power in Afghanistan in August of 2021, nearly 90,000 Afghans who had fled their country have been resettled in the United States, constituting one of the largest groups of refugee arrivals in the U.S. in recent history. Working from a database I created from the administrative records of a non-profit refugee aid group, I use data and spatial analysis to examine the demographics of Afghans resettled in the DC metro area, the characteristics of the census tracts and counties in which they have been resettled, and their access to public transportation. I find that the …

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Canary In The Forest?—Tree Mortality And Canopy Dieback Of Western Redcedar Linked To Drier And Warmer Summers, Robert A. Andrus, L. R. Peach, A. R. Cinquini, Joseph Hulbert, J. T. Yusi, Andres Holz, M. Fischer, Kevan B. Moffett, Multiple Additional Authors Sep 2023

Canary In The Forest?—Tree Mortality And Canopy Dieback Of Western Redcedar Linked To Drier And Warmer Summers, Robert A. Andrus, L. R. Peach, A. R. Cinquini, Joseph Hulbert, J. T. Yusi, Andres Holz, M. Fischer, Kevan B. Moffett, Multiple Additional Authors

Geography Faculty Publications and Presentations

Aim: Forest dieback is increasing from unfavourable climate conditions. Western redcedar (WRC)—a culturally, ecologically and economically important species—has recently experienced anomalously high mortality rates and partial canopy dieback. We investigated how WRC tree growth and dieback responded to climate variability and drought using tree-ring methods. Location: Pacific Northwest, USA. Taxon: Western redcedar (Thuja plicata). Methods: We collected tree cores from three tree health status groups (no canopy dieback, partial canopy dieback, and dead trees) at 11 sites in coastal (maritime climate) and interior (continental climate) WRC populations. From growth rates, we computed four growth indices that assessed the resilience to …

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Structural Tensions Limiting Success Of Infrastructure Upgrading: A Multi-Regime Perspective, George Kiambuthi Wainaina, Bernhard Truffer, James T. Murphy Sep 2023

Structural Tensions Limiting Success Of Infrastructure Upgrading: A Multi-Regime Perspective, George Kiambuthi Wainaina, Bernhard Truffer, James T. Murphy

Geography

Unfettered growth of slums is a daunting transition challenge and many upgrading programs fail to sustainably improve the livelihoods of slum residents. This paper elaborates a transitions perspective on structural tensions that may lead to success or failure of slum upgrading programs. We conceptualize slums as urban subsystems, governed by sociotechnical (infrastructure) and socioeconomic livelihood regimes (related to production and social reproduction). The framework permits examination of the tensions due to mis/alignments of rules associated with newly introduced infrastructures, and those that regulate existing production and social reproduction practices of slum residents. This approach extends transition studies by accounting for …

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The Town That Built Its Own River: La Plaza Del Cerro At Taos County New Mexico, José A. Rivera Ph.D Sep 2023

The Town That Built Its Own River: La Plaza Del Cerro At Taos County New Mexico, José A. Rivera Ph.D

Faculty Publications

Cerro is an unincorporated community in Taos County, New Mexico, and is situated near New Mexico State Highway 522 heading north to the Colorado border. Nearby is Cerro de Guadalupe, a peak that has an elevation of 8,796 feet and Cerro at 7,490 feet. The connection to Guadalupe Mountain gave the town its original name as “La Plaza del Cerro de Guadalupe.” Cerro was established in the early 1850s by settlers who arrived from nearby Questa and Taos. By itself, Guadalupe Mountain did not provide sufficient water to sustain an agrarian economy based on farming and livestock ranching as was …

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‘Following The Line Of Least Resistance’: African American Women In Domestic Work, 1899–1940, Taylor Simsovic Sep 2023

‘Following The Line Of Least Resistance’: African American Women In Domestic Work, 1899–1940, Taylor Simsovic

Armstrong Undergraduate Journal of History

This paper examines the challenges faced by African American women employed in domestic service between 1899 and 1940, with a focus on how race, class, and gender intersected to shape their experiences. Specifically, the study investigates how these women continued to perform reproductive labor as they migrated from the South to Northern states during the Great Migration. Drawing on a range of primary and secondary sources, the analysis argues that Black women's persistent employment in undervalued labor within white American homes was driven by the mutually constitutive systems of capitalism, white supremacy, and patriarchy. These systems channeled Black women into …

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Lightning-Ignited Wildfires In The Western United States: Ignition Precipitation And Associated Environmental Conditions, Dmitri Alexander Kalashnikov, John T. Abatzoglou, Paul Loikith, Nicholas J. Nauslar, Yianna Sotirios Bekris, Deepti Singh Sep 2023

Lightning-Ignited Wildfires In The Western United States: Ignition Precipitation And Associated Environmental Conditions, Dmitri Alexander Kalashnikov, John T. Abatzoglou, Paul Loikith, Nicholas J. Nauslar, Yianna Sotirios Bekris, Deepti Singh

Geography Faculty Publications and Presentations

Cloud-to-ground lightning with minimal rainfall (“dry” lightning) is a major wildfire ignition source in the western United States (WUS). Although dry lightning is commonly defined as occurring with <2.5 mm of daily-accumulated precipitation, a rigorous quantification of precipitation amounts concurrent with lightning-ignited wildfires (LIWs) is lacking. We combine wildfire, lightning and precipitation data sets to quantify these ignition precipitation amounts across ecoprovinces of the WUS. The median precipitation for all LIWs is 2.8 mm but varies with vegetation and fire characteristics. “Holdover” fires not detected until 2–5 days following ignition occur with significantly higher precipitation (5.1 mm) compared to fires detected promptly after ignition (2.5 mm), and with cooler and wetter environmental conditions. Further, there is substantial variation in precipitation associated with promptly-detected (1.7–4.6 mm) and holdover (3.0–7.7 mm) fires across ecoprovinces. Consequently, the widely-used 2.5 mm threshold does not fully capture lightning ignition risk and incorporating ecoprovince-specific precipitation amounts would better inform WUS wildfire prediction and management.

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Audible Futures: Scenes Of Sonic Encounter In Cold War Kurdistan, 1923–2023, Nicholas S. Glastonbury Sep 2023

Audible Futures: Scenes Of Sonic Encounter In Cold War Kurdistan, 1923–2023, Nicholas S. Glastonbury

Dissertations, Theses, and Capstone Projects

This dissertation examines a century of cultural politics in Kurdistan, from 1923 to 2023, and it does so from a relatively marginal vantage point in most histories of Kurdistan: that of the Soviet Caucasus. It takes as its primary object the cultural and political itineraries of sonic media and listening in Kurdistan, from Soviet Kurdish radio broadcasting and pirated cassettes to postsocialist archives, DJ booths, and streaming music. These itineraries map not only the emergence and circulation of Kurdish notions of tradition, heritage, and cultural memory, but also the methods of counterinsurgency deployed by the states that occupy Kurdistan. In …

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Nonprofit Accountability: Effects Of Subsector On Online Accountability, Ibrahima F. Yaro, Trent A. Engbers Aug 2023

Nonprofit Accountability: Effects Of Subsector On Online Accountability, Ibrahima F. Yaro, Trent A. Engbers

Midwest Social Sciences Journal

Scandals within the nonprofit sector over compensation and management have increased calls for nonprofits to demonstrate accountability. Many organizations have responded by disclosing information online and providing tools that allow web-based interactions with stakeholders. The literature on nonprofits’ online accountability has found that the level of nonprofit online accountability is affected by their size, age, asset, revenue, and location, but hasn’t been examined in terms of how subsector influences online accountability. Through a web-content analysis of fifty-five nonprofits, this research investigated how subsector (arts and culture, education, health, and human services) influences online accountability using a framework of four types …

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A Mixed Methods Approach To Understanding The Links Between Mining, Climate Change And Selected Health Outcomes In India, Mary J. Cheruvillil Aug 2023

A Mixed Methods Approach To Understanding The Links Between Mining, Climate Change And Selected Health Outcomes In India, Mary J. Cheruvillil

Dissertations and Theses

Despite ample evidence of the significant role that mining activities play in determining health outcomes, in India there is a dearth of comprehensive health studies that draw linkages between mining and health. The purpose of the following study is to investigate the impact of mining activities on population health in India using three different methods: ecological multivariable regression, exploratory spatial data analysis (ESDA) and content analysis of government documents using a phenomenological approach. The first aim uses the ecological multivariable regression to examine associations between mining activities and children’s malnutrition outcomes at the district level. Census data, the Demographic Health …

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Insar Time Series Analysis To Evaluate Subsidence Risk Of Monumental Chandigarh City (India) And Surroundings, Jungrack Kim, Shih-Yuan Lin, Tejpal Singh, Ramesh P. Singh Aug 2023

Insar Time Series Analysis To Evaluate Subsidence Risk Of Monumental Chandigarh City (India) And Surroundings, Jungrack Kim, Shih-Yuan Lin, Tejpal Singh, Ramesh P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Groundwater depletion is one of the serious geo-environmental issues causing ground subsidence, which damage buildings, infrastructures and causes loss of life. The quantitative and qualitative evaluation of groundwater variability requires multiple approaches to measure hydraulic head level and geodetic deformation. In this study, we have made efforts to integrate multiple hierarchical space-borne data, including Gravity Recovery and Climate Experiment (GRACE), Sentinel-1 Interferometric Synthetic Aperture Radar (InSAR), geological and hydrological data, to quantify subsidence in Chandigarh city and its surroundings. First, we conducted New-Small BAseline Subsets (NSBAS) and pointwise persistent scatterer (PS) InSAR techniques in parallel, using three-years Sentinel-1 data showing …

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Whose Growth In Whose Planetary Boundaries? Decolonising Planetary Justice In The Anthropocene, Farhana Sultana Aug 2023

Whose Growth In Whose Planetary Boundaries? Decolonising Planetary Justice In The Anthropocene, Farhana Sultana

Geography and the Environment - All Scholarship

This critical analysis examines the geopolitics of planetary environmental injustice and the imperative for systems change to address the intertwined crises of climate breakdown and unsustainable economic growth. Climate breakdown has heightened attention to uneven anthropogenic use and abuse of the planet's biosphere and common pool resources. Recent arguments by climate scholars suggest that various planetary boundaries have already been breached, resulting in dramatic and harmful socio-ecological consequences. These trends raise crucial questions of equity and justice, especially concerning responsibilities and impacts. By centring Global South perspectives, prevailing ideologies promoting hyperconsumption, overproduction and waste are interrogated. The incommensurability of socioecological …

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Methodological Analysis On Settler Territoriality And The Rise Of The Yellowstone Wild Bison Advocacy Movement, Red G.R. Burkett Aug 2023

Methodological Analysis On Settler Territoriality And The Rise Of The Yellowstone Wild Bison Advocacy Movement, Red G.R. Burkett

Theses - ALL

Bison bison, also known as the North American Buffalo, are a keystone species of endemic megafauna in the Great Plains prairie ecosystem. Bison were driven nearly to extinction in the late 19th century when millions of buffalo were massacred by settlers in order to starve Indigenous civilians and force them onto federally-managed Reservations as a step in the centuries-long ethnic-cleansing of Turtle Island. Such genocidal methods were a primary tool in erasing the land claims of Indigenous nations and colonizing the territories of Indigenous communities who depended on bison as a primary source of food and materiel for social reproduction. …

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Methodological Analysis On Settler Territoriality And The Rise Of The Yellowstone Wild Bison Advocacy Movement, Red G.R. Burkett Aug 2023

Methodological Analysis On Settler Territoriality And The Rise Of The Yellowstone Wild Bison Advocacy Movement, Red G.R. Burkett

Theses - ALL

Bison bison, also known as the North American Buffalo, are a keystone species of endemic megafauna in the Great Plains prairie ecosystem. Bison were driven nearly to extinction in the late 19th century when millions of buffalo were massacred by settlers in order to starve Indigenous civilians and force them onto federally-managed Reservations as a step in the centuries-long ethnic-cleansing of Turtle Island. Such genocidal methods were a primary tool in erasing the land claims of Indigenous nations and colonizing the territories of Indigenous communities who depended on bison as a primary source of food and materiel for social reproduction. …

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Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed Aug 2023

Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed

Graduate Theses and Dissertations

This dissertation explores the application of remote sensing technologies in conservation agriculture, specifically focusing on identifying and mapping winter cover crops and assessing voluntary cover crop adoption and cropping patterns in the Arkansas portion of the Mississippi Alluvial Plain (MAP). In the first chapter, a systematic review using the PRISMA methodology examines the last 30 years of thematic research, development, and trends in remote sensing applied to conservation agriculture from a global perspective. The review uncovers a growing interest in remote sensing-based research in conservation agriculture and emphasizes the necessity for further studies dedicated to conservation practices. Among the 68 …

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Human–Environment Interactions At Ta’Ab Nuk Na, A Submerged Maya Salt Works Site In Belize, Cheryl M. Foster, Heather Mckillop, Cory Sills Aug 2023

Human–Environment Interactions At Ta’Ab Nuk Na, A Submerged Maya Salt Works Site In Belize, Cheryl M. Foster, Heather Mckillop, Cory Sills

Geography Faculty Publications and Presentations

Sea-level rise and settlement are investigated at Ta’ab Nuk Na, an ancient Maya salt works in Belize, by examining samples from wooden posts and marine sediment. The samples included Post 145 of Building B and the Nunavut beam, along with marine sediment columns cut from beside both wooden posts. The sediment columns were sampled at 2 cm intervals. Loss-on ignition confirmed the presence of organic material. Identifying the organic content involved removing nonorganic material from the sediment and sorting the organic material under magnification. This procedure established that most of the organic material was red mangrove (Rhizophora mangle). Red mangroves …

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A Systematic Review On The Ecosystem Services Provided By Green Infrastructure, Daniel Jato-Espino, Fabio Capra-Ribeiro, Vanessa Moscardó, Leticia Bartolome Del Pino, Fernando Mayor-Vitoria, Laura Gallardo, Patricia Carracedo, Kristin Dietrich Aug 2023

A Systematic Review On The Ecosystem Services Provided By Green Infrastructure, Daniel Jato-Espino, Fabio Capra-Ribeiro, Vanessa Moscardó, Leticia Bartolome Del Pino, Fernando Mayor-Vitoria, Laura Gallardo, Patricia Carracedo, Kristin Dietrich

Faculty Publications

Urbanization and climate change are endangering the sustainability of public spaces through increased land artificialization, ecological fragmentation, reduced resource availability, and limited accessibility to natural and seminatural areas. Properly managing Green Infrastructure (GI) can contribute to mitigating these challenges by delivering multiple provisioning, regulating, supporting and cultural Ecosystem Services (ES). This would facilitate the implementation of strategically planned GI networks in cities for urban regeneration purposes. In this context, this study developed a systematic review on the ES provided by GI using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The analysis of 199 eligible articles indicated …

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U-Net-Stn: A Novel End-To-End Lake Boundary Prediction Model, Lirong Yin, Lei Wang, Tingqiao Li, Siyu Lu, Zhengtong Yin, Xuan Liu, Xiaolu Li, Wenfeng Zheng Aug 2023

U-Net-Stn: A Novel End-To-End Lake Boundary Prediction Model, Lirong Yin, Lei Wang, Tingqiao Li, Siyu Lu, Zhengtong Yin, Xuan Liu, Xiaolu Li, Wenfeng Zheng

Faculty Publications

Detecting changes in land cover is a critical task in remote sensing image interpretation, with particular significance placed on accurately determining the boundaries of lakes. Lake boundaries are closely tied to land resources, and any alterations can have substantial implications for the surrounding environment and ecosystem. This paper introduces an innovative end-to-end model that combines U-Net and spatial transformation network (STN) to predict changes in lake boundaries and investigate the evolution of the Lake Urmia boundary. The proposed approach involves pre-processing annual panoramic remote sensing images of Lake Urmia, obtained from 1996 to 2014 through Google Earth Pro Version 7.3 …

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Object-Oriented Remote Sensing Approaches For The Detection Of Terrestrial Impact Craters As A Reconnaissance Survey, Habimana Emmanuel, Jaehyung Yu, Lei Wang, Sung Hi Choi, Digne Edmond Rwabuhungu Rwatangabo Aug 2023

Object-Oriented Remote Sensing Approaches For The Detection Of Terrestrial Impact Craters As A Reconnaissance Survey, Habimana Emmanuel, Jaehyung Yu, Lei Wang, Sung Hi Choi, Digne Edmond Rwabuhungu Rwatangabo

Faculty Publications

The purpose of this study is to employ a remote sensing reconnaissance survey based on optimal segmentation parameters and an object-oriented random forest approach to the identification of possible terrestrial impact craters from the global 30-m resolution SRTM DEM. A dataset consisting of 94 confirmed and well-preserved terrestrial impact craters, 104 volcanic calderas, and 124 valleys were extracted from real-world surface features. For craters with different sizes, eight optimal scale parameters from 80 to 3000 have been identified using multi-resolution segmentation, where the scale parameters have a positive correlation (R2 = 0.78) with the diameters of craters. The object-oriented random …

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Water Quality Land Cover Change And Water Quality In Wetlands At The City Of Gresham, Or, Evelyn Barajas, Michael Gonzalez Aug 2023

Water Quality Land Cover Change And Water Quality In Wetlands At The City Of Gresham, Or, Evelyn Barajas, Michael Gonzalez

altREU Projects

The City of Gresham, Oregon has implemented constructed wetlands around the area as an attempt to collect, filter, and purify water from different sources such as rain, agricultural waste, and domestic waste. We focused our research on three different facilities: Columbia Slough Water Quality Facility (CSWQF), Fairview Creek Water Quality Facility, and Brookside Water Quality Facility. For each of these, we conducted tests and looked at the concentration levels for nitrogen and phosphorus nutrients such as NH3-N (ammonium), NO3-N (nitrate), TKN (total Kjeldahl nitrogen), O-PO4 (phosphate), and Total P (total phosphorus), as well as heavy metals like Total Cu (total …

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The Dynamic Nature Of Wrack: An Investigation Into Wrack Movement And Impacts On Coastal Marshes Using Suas, Grayson R. Morgan, Daniel R. Morgan, Cuizhen Wang, Michael E. Hodgson, Steven R. Schill Aug 2023

The Dynamic Nature Of Wrack: An Investigation Into Wrack Movement And Impacts On Coastal Marshes Using Suas, Grayson R. Morgan, Daniel R. Morgan, Cuizhen Wang, Michael E. Hodgson, Steven R. Schill

Faculty Publications

This study investigates the use of small unoccupied aerial systems (sUAS) as a new remote sensing tool to identify and track the spatial distribution of wrack on coastal tidal marsh systems. We used sUAS to map the wrack movement in a Spartina alterniflora-dominated salt marsh monthly for one year including before and after Hurricane Isaias that brought strong winds, rain, and storm surge to the area of interest in August 2020. Flight parameters for each data collection mission were held constant including collection only during low tide. Wrack was visually identified and digitized in a GIS using every mission orthomosaic …

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Using Terrestrial Laser Scanning To Estimate Canopy Structure In Peatland Conifers Under A Climate Manipulation, Angela D. Seibert Aug 2023

Using Terrestrial Laser Scanning To Estimate Canopy Structure In Peatland Conifers Under A Climate Manipulation, Angela D. Seibert

Boise State University Theses and Dissertations

Northern peatlands are major terrestrial carbon sinks, storing 415 ± 150 Gt of carbon. The composition of peatland vegetation affects this carbon storage capacity, and thus quantifying the vegetation helps to constrain uncertainty in peatland carbon storage estimates. Ground layer vegetation, such as Sphagnum sp. moss contributes greatly to carbon storage capacity. In forested peatlands, the tree canopy structure directly influences peatland solar insolation, soil temperature, and water table levels. Each of these factors impacts the ground layer vegetation. Currently, there is uncertainty about how the peatland tree canopy structure is influenced by elevated levels of carbon dioxide (CO2 …

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Heat Mapping Crime: A Data-Driven Approach To Policing In New York, Beruktawit Gebreamlak, Daniel Ochoa Aug 2023

Heat Mapping Crime: A Data-Driven Approach To Policing In New York, Beruktawit Gebreamlak, Daniel Ochoa

altREU Projects

In the aftermath of the COVID-19 pandemic, New York City has seen a surge in criminal activities. In 2023, major crime continues to be higher compared to pre-pandemic levels. Although progress is being made to reduce the number of murders and robberies, law enforcement is continuing to struggle with increases in felony assaults and car thefts. Our project serves to benefit members of the community and law enforcement alike. We created a heat map, which is a visual representation of data that uses colors to represent different values. In the context of crime mapping, our heat map is used to …

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Spatial Analysis Of Streamflow Trends In Burned Watersheds Across The Western Contiguous United States, Heejun Chang, Will B. Long Aug 2023

Spatial Analysis Of Streamflow Trends In Burned Watersheds Across The Western Contiguous United States, Heejun Chang, Will B. Long

Geography Faculty Publications and Presentations

Despite increasing magnitude and frequency of wildfire, understanding hydrological processes contributing to changes in streamflow is not well examined for the entire western contiguous United States (WCONUS). This study provides insight into whether considering spatially varying watershed characteristics, including burn severity patterns, can better explain streamflow trends at broad spatial and temporal scales. Standard geographically weighted regression (GWR) and multi-scalar (MS) GWR were benchmarked against ordinary least squares (OLS) regression to determine if spatially varying coefficients could better explain spatially varying patterns and processes of peak flow, low flow, center timing of flow, and flashiness trends in burned watersheds. In …

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Wildfire Risk Governance From The Bottom Up: Linking Local Planning Processes In Fragmented Landscapes, Matthew Hamilton, Max Nielsen-Pincus, Cody Evers Aug 2023

Wildfire Risk Governance From The Bottom Up: Linking Local Planning Processes In Fragmented Landscapes, Matthew Hamilton, Max Nielsen-Pincus, Cody Evers

Environmental Science and Management Faculty Publications and Presentations

The growing scale of natural hazards highlights the need for models of governance capable of addressing risk across administrative boundaries. However, risk governance systems are often fragmented, decentralized, and sustained by informal linkages among local-level risk mitigation planning processes. Improving resilience to the effects of environmental change requires a better understanding of factors that contribute to these linkages. Using data on the patterns of participation of 10,199 individual stakeholders in 837 community wildfire protection plans (CWPPs) within the western U.S., we document the emergence of a locally clustered but spatially extensive wildfire risk governance network. Our evaluation of factors that …

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Improved Fine-Scale Tropical Forest Cover Mapping For Southeast Asia Using Planet-Nicfi And Sentinel-1 Imagery, Feng Yang, Xin Jiang, Alan D. Ziegler, Lyndon Estes, Jin Wu, Anping Chen, Philippe Ciais Aug 2023

Improved Fine-Scale Tropical Forest Cover Mapping For Southeast Asia Using Planet-Nicfi And Sentinel-1 Imagery, Feng Yang, Xin Jiang, Alan D. Ziegler, Lyndon Estes, Jin Wu, Anping Chen, Philippe Ciais

Geography

The accuracy of existing forest cover products typically suffers from “rounding” errors arising from classifications that estimate the fractional cover of forest in each pixel, which often exclude the presence of large, isolated trees and small or narrow forest clearings, and is primarily attributable to the moderate resolution of the imagery used to make maps. However, the degree to which such high-resolution imagery can mitigate this problem, and thereby improve large-area forest cover maps, is largely unexplored. Here, we developed an approach to map tropical forest cover at a fine scale using Planet and Sentinel-1 synthetic aperture radar (SAR) imagery …

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Conceptual And Technological Advancements In Visitor Use Management Of Coastal And Estuarine Environments, Tyler Cribbs Aug 2023

Conceptual And Technological Advancements In Visitor Use Management Of Coastal And Estuarine Environments, Tyler Cribbs

All Dissertations

This dissertation demonstrates the exploration and use of conceptual and technological advancements in the science of visitor use management (VUM). The goal of this effort is to help better understand visitors to park and protected areas (PPAs) and more specifically, better manage our coastal and estuarine environments (i.e., coastal protected areas (CPAs). These concepts and techniques are 1) further implementing the use of cellphone data in recreation ecology and VUM, 2) assessing the use of advanced imagery, virtual reality (VR), in visual-based methods to determine visitor indicators and thresholds, and 3) assessing visitor’s awareness of PPAs and how it influences …

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A Comparative Study Of Vinti-Based Orbit Propagation And Estimation For Cubesats In Very Low Earth Orbits, Ethan Michael Senecal Aug 2023

A Comparative Study Of Vinti-Based Orbit Propagation And Estimation For Cubesats In Very Low Earth Orbits, Ethan Michael Senecal

Mechanical & Aerospace Engineering Theses & Dissertations

In recent years, there has been a growing interest in CubeSats and very low Earth orbit (VLEO) space missions. Mission SeaLion, a collaborative CubeSat mission between Old Dominion University, the U.S. Coast Guard Academy, and U.S. Air Force Institute of Technology, planned to launch a 3U CubeSat into VLEO. The VLEO mission is a particularly challenging environment for navigation and orbit propagation because drag introduces a significant perturbation for orbit models such as SGP4. Additionally, mission requirements left no capacity for attitude determination or control, further reducing knowledge of drag behavior of the satellite in flight. This deficiency is a …

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Projecting Vegetation Condition And Fire Risk In Southern California, Westin K. Guthrie Aug 2023

Projecting Vegetation Condition And Fire Risk In Southern California, Westin K. Guthrie

Geography ETDs

In the western US, relationships between fire, vegetation, climate, and urban areas are dynamic and evolving. This work used a forest landscape model, LANDIS-II, informed by future climate scenarios and projections of urban expansion to understand wildfire interactions within projected Wildland Urban Interface (WUI) areas. This simulation showed that in both 2050 and 2100 +93% of the WUI in southern California experienced fire. Future work needs to be done in parametrizing forest biomass to ensure the validity of projections. Additionally, increasing each climate scenario model's replicates will create more accurate projections.

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Urban Sustainability Implementation And Indicators In The United States: A Systematic Review, Heejun Chang, Arun Pallathadka, Idowu Ajibade Aug 2023

Urban Sustainability Implementation And Indicators In The United States: A Systematic Review, Heejun Chang, Arun Pallathadka, Idowu Ajibade

Geography Faculty Publications and Presentations

Urban sustainability is the goal of many cities in the world, yet very few have achieved a level of sustainability that goes beyond the most basic environmental objectives. The practice and assessment of sustainability implementation are greatly compounded by lack of funding, technical know-how, political will, and the power disparity between dominant institutions and marginalized communities. This systematic analysis of urban sustainability literature involved the review of 241 studies published between 2010 and 2022. We critically examined current debates and challenges in urban sustainability, identifying gaps and opportunities and providing recommendations for creating equitable, just, and sustainable urban futures. We …

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