Digital Commons Network^™

Estimating Medium-Term Regional Monthly Economic Activity Reductions During The Covid-19 Pandemic Using Nighttime Light Data, Ma Flordeliza P. Del Castillo, Toshio Fujimi, Hirokazu Tatano

SOSE Affiliate: Manila Observatory

Economic impact estimates of the initial lockdowns due to the COVID-19 pandemic showed a significant reduction in economic activities globally. However, the succeeding impacts and their spatiotemporal distribution within countries remain unknown. Studies showed that nighttime light data (NTL) has effectively revealed the spatiotemporal dimensions of the economic effects of COVID-19. Thus, this study used NTL data to determine the medium-term regional monthly economic impacts of the pandemic in the Philippines in terms of the Economic Activity Reduction (EAR) index. We generated a spatial error model, regressing pre-pandemic NTL on mean temperature, maximum rainfall, and built-up area. This model explained …

Net Evaporation-Induced Mangrove Area Loss Across Low-Lying Caribbean Islands, Isamar M. Cortés, Jorge Lorenzo-Trueba, Andre S. Rovai, Robert R. Twilley, Mark Chopping, Temilola Fatoyinbo

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Although mangroves provide many beneficial ecosystem services, such as blue carbon storage and coastal protection, they are currently under threat due to changes in climate conditions, such as prolonged drought exposure. Under drought conditions, evaporation exceeds precipitation and high soil salinities can lead to stunted growth and die-back. To quantify this interplay, we developed a database for low-lying and uninhabited mangrove islands in the Caribbean under various evaporation and precipitation regimes. We extracted physical and biological information from each island using remote sensing techniques and coupled it with a process-based model. We used this database to develop a model that …

Interpreting Strain Caused By Transient Well Testing, Soheil Roudini

All Dissertations

Understanding reservoir properties and structure is essential to managing subsurface operations, such as geologic storage of CO₂ or production of water, hydrocarbons or heat. Previous work demonstrated the potential of analyzing strain data during transient well tests by estimating hydraulic diffusivity using a type-curve-like approach. The following dissertation aims to pursue this potential by developing and evaluating methods for interpreting strain tensor data to improve subsurface characterization. The research advances the classic, intuitive method of using type-curves to interpret well tests, but it also brings together modern computational methods from machine learning, proxy modeling and Bayesian inversion, and it …

An Analysis Of Policies, Practices, And Barriers To Create A Multi-Dimensional Approach To Renewable Energy Transition For Us Communities, Hanan Wehbi

Graduate Theses and Dissertations

The transition from fossil fuel-derived energy resources to clean, renewable, affordable, and reliable energy necessitates a comprehensive approach. This approach must incorporate an interdisciplinary contribution to ensure the sustainability, efficiency, and resilience of the energy system. In the United States, many communities and local governments are developing ambitious plans, regulations, and targets to support the renewable energy transition and enhance energy efficiency. This research builds on the principles of sustainable development planning and transition theory to develop a framework that assists communities in planning their renewable energy (RE) transition and integrate these plans in their long- and short-term development approaches. …

Informing Management Of American Shad (Alosa Sapidissima) In The Carolinas: Evaluating Novel Fish Passage Approaches And Acoustic Tracking Methods, Margaret Gaither

All Theses

Acoustic telemetry is a valuable tool for fisheries scientists to study the movements and migratory behaviors of aquatic organisms. A critical assumption of this method is that tagged fish exhibit similar behaviors and survival rates as their untagged counterparts. To investigate this, we conducted a 12-week laboratory study on adult American Shad (Alosa sapidissima) using gastroesophageal insertion of acoustic transmitters. We implanted 80 fish with dummy transmitters and monitored tag retention and survival. Our analysis, employing a mixed effects Cox’s proportional hazards model, revealed no significant differences in survival between tagged and control fish, regardless of sex. Additionally, …

Recreational Fishing For Western Rock Lobster: Estimates Of Participation, Effort And Catch In 2023/24, Claire B. Smallwood, Karina L. Ryan, Alissa C. Tate

Fisheries Research Reports

The Western Rock Lobster (WRL) (Panulirus cygnus) is the most commonly caught Rock Lobster (RL) species in Western Australia. Catches from the commercial and recreational sectors are required to determine and monitor Total Allowable Commercial Catch (TACC), Total Allowable Recreational Catch (TARC) and the proportion of Allowable Harvest Level (AHL) achieved. The TARC is set at 5% of the AHL and evaluated in the harvest strategy based on a 5-year average.

Data for the recreational sector are obtained using phone-recall surveys to provide annual estimates of participation, fishing effort and retained catch (by numbers) from recreational fishers who hold a …

Performance Of Acoustic Telemetry And Space Use Of Pallid Sturgeon In The Lower Platte River, Nebraska, Christopher F. Pullano

School of Natural Resources: Dissertations, Theses, and Student Research

Pallid Sturgeon (Scaphirhynchus albus) are centenarian, potamodromous, rheophiles that historically occupied the Missouri River and Mississippi River basins. Listed on the U.S. Endangered Species Act in 1990, population declines are attributed to habitat fragmentation and degradation, as well as overharvest, and hybridization. A knowledge gap exists regarding the extent to which tributaries facilitate key life stages for Pallid Sturgeon. This study evaluated the capacity of acoustic telemetry to monitor the movements of Pallid Sturgeon in a shallow, braided tributary to the Missouri River. The specific objectives were to (1) evaluate the environmental variables influencing the performance of acoustic …

Spatial Ecology Of American Bison On Vermejo Park Ranch, New Mexico, Kate Ann Asmus

School of Natural Resources: Dissertations, Theses, and Student Research

American bison (Bison bison) are a keystone species that impact grassland productivity, plant diversity, and landscape heterogeneity. We used GPS telemetry and a replicate herbivore grazing experiment on Vermejo Park Ranch in northeastern New Mexico to advance understanding of bison spatial ecology and grazing dynamics. First, we evaluated the potentially disparate influences of forage productivity and site fidelity on the size and selection of home ranges of bison. Home range size was strongly negatively influenced by forage productivity. However, home range selection was influenced more strongly by site fidelity than spatial variation in forage, as bison selected home …

Time Series Decomposition Of Land Surface Temperature For Long-Term Trend Forecasting And Impact On Nesting Sea Turtle Habitats In The Arabian Gulf, Sachi Perera, Rommel H. Maneja, Mohamed Allali, Cyril Rakovski, Erik Linstead, Daniele Struppa, Ali Qasem, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Improving land surface temperature (LST) modeling is vital for mitigating climate change effects on various ecosystems and marine habitats such as important sea turtle habitats. Over the past decade, extreme temperatures have likely significantly affected nesting sea turtle habitats in the Arabian Gulf, with predominantly female hatchlings creating an imbalance in the sex ratio. Such shifts have profound implications for these habitats’ long-term survival and conservation management. This study leverages statistical machine learning models to measure ongoing temporal variations in LST. We break down the LST time series into trend, seasonal, and noise components using classical decomposition methods like X11, …

Structure Modifications And Alternative Monitoring Designs Of Wildlife Road Mitigation Structures, Madison T. Nadler

Theses and Dissertations

Wildlife mitigation structures are designed to keep animals off roadways while providing them safe passage to the other side and not impeding traffic flow. Camera traps are commonly used to assess the success of these mitigation structures, but there are downfalls to both the methods and structures. Alternative mitigation structure designs are needed to better prevent wildlife from accessing roadways in areas where they should be deterred. Additionally, traditional camera trapping methods do not accurately capture the full wildlife communities that may be utilizing these structures and other survey methods are needed, specifically aimed at small mammals, amphibians, and reptiles. …

Examining Hispanic Beginning Farmers And Ranchers In The Rio Grande Valley Through A Community Capitals Framework, Perla Kimberly Schrock

Theses and Dissertations

While existing literature addresses the experiences of beginning farmers and ranchers (BFR), there is a notable gap in research focused on Hispanic beginning farmers and ranchers (HBFR). This study aimed at exploring the unique experiences of HBFR in a predominantly Hispanic region, the Rio Grande Valley (RGV), employed the Community Capitals Framework (Flora et al., 2016). I conducted 16 semi-structured interviews with HBFR and local nonprofit organizations and federal employees, complemented by participant observations. Through thematic and content analysis of the interview transcripts, findings revealed valuable insights into the livelihoods of HBFR. Despite HBFR facing significant challenges, this study demonstrated …

Environmental Dna Identifies Coastal Plant Community Shift 1,000 Years Ago In Torrens Island, South Australia, Nicole R. Foster, Alice R. Jones, Oscar Serrano, Anna Lafratta, Paul S. Lavery, Kor-Jent Van Dijk, Ed Biffin, Bronwyn M. Gillanders, Jennifer Young, Pere Masque, Patricia S. Gadd, Geraldine E. Jacobsen, Atun Zawadzki, Andria Greene, Michelle Waycott

Research outputs 2022 to 2026

Anthropogenic activities are causing detrimental changes to coastal plants– namely seagrass, mangrove, and tidal marshes. Looking beyond recent times to past vegetation dynamics is critical to assess the response and resilience of an environment to change. Here, we develop a high-resolution multi-proxy approach, providing a new evidence base to decipher long-term change in coastal plant communities. Combining targeted environmental DNA analysis with chemical analysis of soils, we reconstructed 4,000 years of change at a temperate wetland on Torrens Island South Australia and identified an ecosystem shift that occurred ~ 1000 years ago. What was once a subtidal seagrass system shifted …

Assessing Khumbu Region Glaciers Mass Balance Change Using Geospatial Techniques From 2012 To 2024, Yashvi Jagatbhai Shah

Electronic Theses, Projects, and Dissertations

The glaciers in the Hindu Kush Himalaya are critical for sustaining the water supply of South Asia's major rivers, upon which over 230 million people, both in the mountainous regions and lowland areas, depend. Climate change is driving rapid glaciers melt near the summit of Mount Everest, located at an elevation of approximately 7,906 meters (25,938 feet). This has resulted in glacier thinning occurring up to 80 times faster than the original ice formation. However, due to their disposition in a complex topographic setting and inaccessible terrain, continuous glacier observations pose significant challenges.

This study evaluated the mass balance of …

Landslide Inventory And Unstable Slope Monitoring Along Highways In Eastern Tennessee, Robert Mcsweeney

Electronic Theses and Dissertations

This research introduces an unstable slope management program (USMP) for Tennessee based on federal slope management standards, along with improved methods for landslide monitoring with unmanned aerial systems (UAS) lidar and photogrammetry. In mountainous regions, monitoring slope hazards is a critical function of transportation management. A mobile field assessment form created with Survey123 was used to collect 22 unstable slope ratings in eastern Tennessee. Location points were appended with photographs, notes, and site information. Landslide scores ranged from 325 (Fair) to 1005 (Poor). UAS monitoring of a slow-moving soil landslide along I-40 near Rockwood, TN, produced high-resolution lidar and photogrammetry …

Nature-Based Solutions For Flood Risk Mitigation: Mapping And Hydrological Modeling In An Under-Resourced Urban Area On The Mississippi Gulf Coast, Jennifer Makenzie Holifield

Master's Theses

Flooding is the most frequent and costly disaster in the United States, affecting people disproportionately based on environmental, societal, and economic limitations. Through stakeholder engagement, open-access research, and nature-based solutions (NBS), ecology and hydrology can be bridged with local-scale politics to raise awareness of local issues and form strong interdisciplinary bonds. I approached nature-based equity from a ground front, in which I engaged with local stakeholders and city officials to gain insight and calibration on flooding experiences and flooding presence within Moss Point, MS. This engagement helped calibrate GIS models, from which, I found that the flooding hazards of Moss …

Morphometric Based Roughness Estimates For Wind Loading Applications In The Coastal Transition Zone, Hadley Rose Besing

Theses and Dissertations

This project was developed to support the Florida Tech Wireless Sensor Network System (WSNS) hurricane research team in determining wind loads during high-impact wind events. The WSNS team objectives included estimating the critical pressure (𝐶_p) from observed 3-s gusts during high impact weather events (tropical cyclones). The field work was conducted at a single-story residential home in Satellite Beach, FL approximately 400 m from the coast. During data collection periods, more than 1-million 20-second LiDAR wind profiles were observed.

The bulk roughness at the test residence is characterized utilizing an existing morphometric technique with geometry that is derived …

Phytoplankton Responses To Changing Irradiance And Carbon Fertilization, Alison Siersma

Graduate Theses and Dissertations (2019 - present)

Phytoplankton play a crucial role in marine ecosystems due to their innate ability to fix carbon. As atmospheric CO2 levels continue to rise from fossil fuel combustion, the resulting increase in dissolved CO2 and the concurrent decrease in ocean pH are likely to impact the phytoplankton community. The response of phytoplankton to elevated CO2 can vary significantly among species and environmental conditions (e.g. light, temperature, nutrient availability). To address these variations, an experiment was conducted using a controlled photobioreactor system, maintaining high and low light, constant temperature, nutrient levels, and two pCO2 concentrations. This study focused on two regionally relevant …

Leveraging High-Frequency Water Quality Data And Machine Learning For Monitoring Harmful Algal Blooms, Ibrahim Busari

All Dissertations

Freshwater management is one of the most critical resources on the earth due to the plethora of water use and its limited availability. Increased algae proliferation is one of the significant problems of freshwater bodies that is triggered by nutrient enrichment and enabling conditions such as light and warm temperatures. This algal proliferation is toxic to the ecosystem through their biomass and potential toxin production that can cause hypoxic conditions and is often referred to as Harmful Algal Blooms (HABs). Current monitoring approaches include laboratory analysis of water samples to observe algal cells, monitoring of water quality parameters using water …

Redefining Approaches For Measuring Landscape Subsidence And Permafrost Degradation In Arctic Tundra Environments, Tabatha Lynn Fuson

Open Access Theses & Dissertations

As climate change accelerates in the Arctic, the degradation of permafrost is leading to significant landscape transformation in tundra landscapes. This dissertation investigates the multifaceted responses of permafrost systems to warming, focusing on the dynamics of surface elevation changes and active layer thickness (ALT) across the North Slope of Alaska. In this study, I explore the capacity of repeat Terrestrial Laser Scanning (TLS) technology for modeling tundra features and detecting surface subsidence, specifically how different climate and landscape conditions during scanning impact TLS model precision. We also compare TLS model precision estimates to TLS model accuracy by comparing elevation values …

The New Anthropocentrism: The Problem Of Water Conservation And Water Justice, Benjamin Stuart Milam

Open Access Theses & Dissertations

My objective with my thesis is to argue for and reinforce a type of anthropocentrism that is both environmentally conscious and consumable for an audience that is not necessarily well versed in philosophical literature. In the first chapter I go over philosophical frameworks, such as Anthropocentrism and Biocentrism, and why I believe they do not meet both of those criteria listed. After that I discuss New Anthropocentrism, coined by Clive Hamilton, and why I believe that a slightly modified version possesses qualities that I believe are needed for the crisis at hand. In chapter 2 I use that framework and …

The Relationship Between Salvinia Molesta Infestation And The Microbial Ecology Of Wetlands At Caddo Lake, Tx, Usa, Martin Hadsell

Electronic Theses and Dissertations

Wetlands are known to host many beneficial geochemical processes such as nutrient cycling and carbon sequestration. These processes are primarily driven by the microbial communities within a wetland. The establishment of non-native invasive species within wetlands has the potential to alter the once beneficial functionality of wetland microbial communities due to the sensitivity microbes have towards environmental changes. Because of this, several metagenomic studies have been conducted to assess microbial community response to aquatic plant invasion; however, there haven’t been any studies researching the influence of Salvinia molesta (D.S. Mitch.), commonly known as Giant Salvinia, on microbial communities. The goal …

Array Of Graphene Solar Cells On 100 Mm Silicon Wafers For Power Systems, Syed M. Rahman, Md R. Kabir, Tamzeed B. Amin, James M. Mangum, Ashaduzzaman, Paul M. Thibado

Physics Faculty Publications and Presentations

High electrical conductivity and optical transparency make graphene a suitable candidate for photovoltaic-based power systems. In this study, we present the design and fabrication of an array of graphene-based Schottky junction solar cells. Using mainstream semiconductor manufacturing methods, we produced 96 solar cells from a single 100 mm diameter silicon wafer that was precoated with an oxide layer. The fabrication process involves removing the oxide layer over a select region, depositing metal contacts on both the oxide and bare silicon regions, and transferring large-area graphene onto the exposed silicon to create the photovoltaic interface. A single solar cell can provide …

Multi-Temporal Analysis Of Urbanization-Driven Slope And Ecological Impact Using Machine-Learning And Remote Sensing Techniques, Zhang Hao, Muhammad Haseeb, Zheng Xiangtian, Zainab Tahir, Syed Amer Mahmood, Aqil Tariq, Rana Waqar Aslam, M. Abdullah-Al-Wadud, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Rapid urbanization in Lahore, Pakistan, has led to significant ecological and thermal challenges, particularly the intensification of Urban Heat Island (UHI) effects and increased thermal stress as measured by the Urban Thermal Field Variance Index (UTFVI). This study employs a multi-temporal evaluation of Landsat satellite imagery and GIS-based analysis to investigate the Spatio-temporal trends in land-use and land-cover (LULC) changes from 1994 to 2024. We detected substantial changes in urban growth, vegetation cover, and barren areas using supervised classification (Random Forest) methods and remote sensing indices such as NDVI (Normalized Difference Vegetation Index), NDMI (Normalized Difference Moisture Index), NDBI (Normalized …

Butte Reduction Works (Brw) Phase Ii Interim Demolition Plan Construction Drawings And Floodplain Encroachment Analysis, Pioneer Technical Services, Inc., Josh Bryson

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Understanding Mechanisms For Coastal Marsh Sustainability In A Changing Climate, Ashley R. Booth

LSU Doctoral Dissertations

In the Chenier Plain of Louisiana and Texas, coastal marshes are subject to high rates of relative sea level rise (RSLR), restricted sedimentation, and declining elevation attributed to subsidence and decades of intensive management. These marshes were created via mineral sedimentation but now largely accrete via organic matter accumulation. This organic matter accumulation (OMA) – or the balance between plant productivity and decomposition – is essential for maintaining elevation and thus long-term sustainability. However, management for elevation is complicated by a poor understanding of how abiotic factors like flooding and salinity impact processes driving OMA and elevation. To better understand …

A Smogn-Based Mpso-Bp Model To Predict The Height Of A Hydraulically Conductive Fracture Zone, Liu Qi, Liang Zhihao, Zi Jianxiao

Coal Geology & Exploration

Objective The height of a hydraulically conductive fracture zone, a significant factor influencing roof water inrushes and groundwater resource loss, is identified as a research focus of the prevention and control of mine water disasters. Methods To accurately predict the heights of hydraulically conductive fracture zones in coal seam roofs, five parameters were selected as the primary factors influencing hydraulically conductive fracture zones the mining depth: mining height, coal seam inclination, the length of the mining face along its dip direction, proportional coefficient of hard rocks (i.e., the ratio of the cumulative thickness of hard rocks within the statistical height …

Surfaced-Related Multiple Attenuation Using The Cnn Method In The Nmo Domain, Huang Zhufu, Liu Jianfeng, Fang Wenqian, Fu Lihua

Coal Geology & Exploration

Objective The presence of surface-related multiples results in a lower accuracy in seismic data interpretations, and the effective multiple attenuation is a key step in seismic data processing. Multiples are coherent noise signals with similar characteristics to effective signals. It is difficult impossible to distinguish multiple signals from full-wave field data using a traditional convolutional neural network (CNN). Additionally, since the surface-related multiples vary significantly with surveyed areas, the CNN method will face more severe challenges when being transferred to other networks. Methods This study developed a CNN method based on the normal moveout correction (NMO) domain by introducing physical …

Spatial Gap-Filling Of Himawari-8 Hourly Aod Products Using Machine Learning With Model-Based Aod And Meteorological Data: A Focus On The Korean Peninsula, Youjeong Youn, Seoyeon Kim, Seung Hee Kim, Yangwon Lee

Institute for ECHO Articles and Research

Given the complex spatiotemporal variability of aerosols, high-frequency satellite observations are essential for accurately mapping their distribution. However, optical remote sensing encounters difficulties in detecting Aerosol Optical Depth (AOD) over cloud-covered regions, creating data gaps that limit comprehensive environmental analysis. This study introduces a spatial gap-filling method for Himawari-8/Advanced Himawari Imager (AHI) hourly AOD data, using a Random Forest (RF) model that integrates meteorological variables and model-based AOD data. Developed and validated over South Korea from 1 January to 31 December 2019, the model effectively improved data coverage from 6% to 100%. The approach demonstrated high performance in blind tests, …

What Works When Working Together?: Cross-Sector Collaboration Barriers & Facilitators Of A Built Environment Health Impact Assessment In Southern Nevada, Maxim Gakh, Courtney Coughenour, Bertille Assoumou, Emily C. Strickler, Timothy J. Bungum, Jennifer R. Pharr, Pashtana Usufzy, Megan Mcdonough, Nicole Williams Bungum, Mindy Meacham

Environmental & Global Health Faculty Research

Purpose: Cross-sector collaboration can improve community health because decisions made across sectors influence health. Health Impact Assessments (HIAs) and other health-focused, cross-sector collaborations encounter challenges. This case study uses a completed HIA to explore factors impeding and supporting health-related cross-sectoral collaboration.

Methods: Semi-structured key informant interviews with 10 of 12 HIA working group participants were conducted and analysed using a content analysis approach.

Results: Analysis generated 48 codes across seven themes in three primary groups: HIA as a collaborative tool; logistical and systemic barriers; and benefits and logistical, interpersonal, and sectoral facilitators. Recognizing the importance of knowledge, analysis, and …

Comment Letter For Draft Final Butte Reduction Works (Brw) Smelter Area Mine Waste Remediation And Contaminated Groundwater Hydraulic Control Site Phase Iii Quality Assurance Project Plan (Qapp) (Dated September 25, 2024), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.