Digital Commons Network^™

Re: Approval Letter With Comments For The Butte Priority Soils Operable Unit (Bpsou) Draft Final Annual Operations And Maintenance (O&M) Butte Treatment Lagoons (Btl) System 2024 (Dated May 30, 2025), Emma Rott

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Overcoming Challenges In Mapping Hydrography And Heterogeneity In Urban Landscapes, Kristina G. Hopkins, Rebecca L. Hale, Krista A. Capps, John S. Kominoski, Jennifer L. Morse, Allison H. Roy, Andrew Blinn, Shuo Chen, Liz Ortiz Munoz, Annika Quick, Jacob Rudolph

Environmental Science and Management Faculty Publications and Presentations

Understanding how water moves through a watershed is one of the most fundamental yet often complicated aspects of hydrology, especially in urban areas. Urban infrastructure and water management alter natural hydrological pathways in developed watersheds, which can violate assumptions of a watershed approach to ecosystem science. We focus on two aspects of urban landscapes that often create challenges to model watershed processes within and among urban areas: (1) accurate delineation of urban flow paths and (2) consistent characterisation of the urban landscape within and among cities. Here, we describe these challenges and identify how certain components of these challenges can …

Performance Mapping And Weighting For The Evapotranspiration Models Of The Openet Ensemble, M. Reitz, J. M. Volk, T. Ott, M. Anderson, G. B. Senay, F. Melton, A. Kilic, R. Allen, Joshua B. Fisher, A. Ruhoff, A. J. Purdy, J. Huntington

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Evapotranspiration (ET) accounts for the majority of water available from precipitation in the terrestrial water cycle, and improvements to the accuracy, resolution, and coverage of ET data can enhance hydrologic models and assessments. The OpenET collaboration of six remotely sensed ET modeling teams has demonstrated that an ensemble approach to ET estimation generally provides improved accuracy relative to individual ensemble members. The performance of individual models has been shown to vary by land cover type and climate zone, but a thorough study of the variables that influence model performance differences has not yet been conducted. In this paper, we model …

Determining The Toxic Threshold And Other Use Characteristics For Industrial Hemp Seed Oil Used For Wood Product Protection, Daylan M. Barnes

Theses and Dissertations

Plant-based wood treatments have been utilized for many years, with varying success. Oils such as those extracted from linseed (flax), tung, and hemp plants have been used for thousands of years as finishes on wood. These are all drying oils, which dry to a film when exposed to air. Hemp seed oil has a high fatty acid content and can take a long time to dry on wood products but is valued in woodworking for being easy to use, food-safe, and having little to no odor. In this study, cold-pressed hemp seed oil, blended with a soybean carrier oil, is …

Activation Or Deactivation? Rethinking Ferrate(Vi) Reactivity Within A Broader Modulation Framework, Zepei Tang, Yang Deng

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

No abstract provided.

Tides, Tourists, And Tails: Exploring Human-Wildlife Overlap On The Homer Spit, Alaska, Serena Seiler

Masters Theses & Specialist Projects

Coastal areas present unique challenges for human-wildlife coexistence due to their shared use by people and marine species. The Homer Spit in Homer, AK (59.6481° N, 151.5299° W) is a projection of land into Kachemak Bay on which lodging, restaurants, campgrounds, RV parks, fishing, and a variety of coastal activities exist or occur, especially during the summer months. Two of the most popular nearshore marine mammals that attract visitors are sea otters (Enhydra lutris) and harbor seals (Phoca vitulina). These two species spend time swimming, foraging, and resting around the Spit, potentially resulting in co occurrences with humans. Using a …

Town Of Pawleys Island, Ally Murphy

Goal 15: Life on Land

No abstract provided.

Dream Pilot Project: Analysis Of Groundwater Development At Six Villages In Ethiopia, Lindsay K. Gordon

All Graduate Reports and Creative Projects, Fall 2023 to Present

This study presents a hydrogeologic assessment of the Distributed Renewable Energy Agriculture Modalities (DREAM) pilot project, an ongoing groundwater development initiative in rural Ethiopia. This project integrates solar-powered groundwater infrastructure across six villages to improve water access, agricultural productivity, and economic stability.

Fourteen production wells were installed at Murche, four at Dalle, and additional test wells at Murche, Dalle, Chefe Kora, and Huluku. Transmissivity values and the number of wells at Murche suggest that local water needs are currently being met. In contrast, fewer wells were drilled at Dalle. This reflects the high cost of well construction relative to yield, …

Risk Perceptions And Water Governance: Experiences Of Irrigation Companies In The Great Salt Lake Basin Of Northern Utah, United States, Bailey M. Holdaway

All Graduate Theses and Dissertations, Fall 2023 to Present

Irrigation companies are important water management entities in the Western US. However, these companies often face barriers when managing water. Particularly as the state of Utah grows and water resources are drying, there is much finger pointing at those in irrigation and agriculture for better water management. However, pointing fingers without the participation of these companies often does not lead to effective water management outcomes. Therefore, it is important to understand the role of these irrigation companies, and particularly how they are approaching water management.

I set out to understand the role of these irrigation companies, specifically in the Great …

Not All Political Ties Are The Same: Firms' Ties To The Government And Pollution, Wen Helena Li, Ilya R. P. Cuypers, Gokhan Ertug, Hari Bapuji, Wei Liu

Research Collection Lee Kong Chian School Of Business

Complementing research on the implications of political ties for firms’ strategic decisions and financial performance, recent studies are increasingly focusing on the environmental consequences of firms’ political connections. We contribute to this stream of work by integrating insights from the literature on political ties and the multifaceted nature of governments to explore how the level of government influences the pollution implications of firms’ political ties. Specifically, we theorize and demonstrate that, in China, firms' achieved political ties with high levels of the government reduce pollution, while such ties with low levels of the government increase it. Furthermore, we examine how …

Integrated Sustainability: Unlocking Environmental Potential In Electric Vehicles And Solar Panels, Zachary C. Anderson

Honors Theses

This thesis investigates the environmental, economic, and individual level factors influencing consumer adoption of electric vehicles and solar panels. Through a comprehensive scoping review and case-based analysis, it identifies key incentives and barriers related to purchase intentions for each alternative energy technology. Central factors influencing adoption include cost-related concerns, individual purchasing power, demographic effects, and policy impact. These findings suggest that targeted interventions – specifically those used to amplify incentives and mitigate barriers – can positively impact individual consumer purchase intention, including through bundling options. Highlighting the importance of integrated sustainability, this study explored how electric vehicles and solar panels …

Drift Dynamics Of Early Life-Stage Invasive Carps, Saurav Karki

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Asian carp species pose significant ecological threats to North American freshwater systems due to their invasive nature and prolific reproduction. Their semi buoyant eggs develop while drifting downstream with the river current. Understanding early life-stage transport is therefore critical for predicting recruitment potential and guiding management efforts. Existing fluvial egg drift models, including those relying on 1-D hydraulics and fully 3-D CFD-based models, are either inadequate for complex braided rivers or too computationally demanding for large-scale application. The Platte River in Nebraska, characterized by wide, shallow, multi-threaded channels, is dominated by two-dimensional flow conditions, making a depth-averaged 2-D modeling approach …

Evaluation Of Performance Characteristics And Groundwater Contamination Risks Associated With On-Farm Swine Carcass Disposal Via Composting And Shallow Burial With Carbon, Gustavo Castro Garcia

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation evaluates the performance of three on-farm swine carcass disposal methods: whole carcass composting (WCC), ground carcass composting (GCC), and shallow burial with carbon (SBC), focusing on biosecurity factors and groundwater contamination risks. Foreign animal diseases (FADs), such as African swine fever and classical swine fever, pose severe economic and animal well-being risks if introduced to the United States. With confirmation of an FAD, swine movement will be halted, creating an urgent need for practical, biosecure, and environmentally responsible on-farm disposal strategies for swine carcasses. Nebraska, as a leading swine-producing state, exemplifies the vulnerability of high-density livestock regions to …

Resilience Of Interdependent Transportation And Healthcare Systems: A Simulation-Driven Framework Incorporating Social Equity And Facility Optimization, S. Yasaman Ahmadi

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The overarching goal of this dissertation is to develop an integrated, simulation-driven framework to assess and enhance the resilience of interdependent transportation and healthcare systems before, during, and after natural hazards. By examining how spatial disruptions, social vulnerability, operational constraints, and infrastructure interdependencies affect access to and functionality of hospitals, this research offers a multifaceted evaluation of system performance under stress. This dissertation examines the impact of natural hazards, particularly floods, on the interdependent transportation and healthcare systems. The proposed approach combines and advances GIS-based network analysis, graph-theoretical modeling, and discrete-event simulation to evaluate system performance under different scenarios. The …

Multiscale Drivers Of Water Level Fluctuations And Nutrient Availability In Small Intermittent Reservoirs In The Us Midwest, Uchechukwu Vitus Chinatu Ogbenna

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

Reservoir dynamics are often captured by fluctuations in water surface elevation, which reflect a complex interplay of hydrologic inputs, climatic conditions, land use influences, and management operations. While water level fluctuations (WLFs) in large regulated systems have been widely studied, the drivers and implications of WLFs in small reservoirs, particularly those fed by intermittent streams, remain poorly understood. Here, we examined the temporal dynamics of WLFs and their relationship with nutrient availability in nine small reservoirs in the U.S. Midwest using daily records from 1985 to 2022. We used water level classification from modified Zscore and transition matrices to assess …

Developing Guidance For The Use Of Floating Treatment Wetlands In Brackish Stormwater Ponds, Clare Escamilla

All Dissertations

Stormwater ponds are commonly used as a flood control strategy, particularly in coastal developments. Many coastal stormwater ponds are impaired with high nutrient levels that can lead to algal blooms, impacting the water quality of the pond and surrounding ecosystem. Floating treatment wetlands (FTWs) are one potential strategy that can be implemented in stormwater ponds to reduce high nutrient concentrations, however limited research has been done in brackish waterbodies. To determine the suitability of using FTWs in brackish stormwater ponds this research focused on (1) coastal resident perceptions of FTWs and (2) plants that can be utilized in FTWs deployed …

Assessing Coastal Vulnerability And Climate-Driven Migration Risk In West Africa, Wenzhao Li, Surendra Maharjan, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

This study presents a GIS-based multi-criteria decision-making framework to assess climate-induced migration risk along the West African coast. We developed a comprehensive risk index that integrates environmental hazards such as flood frequency and socio-economic vulnerability indicators, including poverty levels, population density, and adaptive capacity. By utilizing datasets such as the Geocoded Disasters (GDIS) dataset, Social Vulnerability Index (SVI), Poverty and Adaptive Capacity Index (PACI), and the Population Exposure Index (PEI), the study identifies regions most susceptible to displacement. Results reveal that areas like Benin’s Abomey-Calavi, Cotonou, and Akpo-Misserete are especially vulnerable due to high disaster frequency, substantial population exposure, and …

The Effect Of The Markle Mill Dam Removal On The Habitat And Riverine Food Web Of Otter Creek, Jenna Blanton

All-Inclusive List of Electronic Theses and Dissertations

Across the United States, dam removals are increasing in frequency. Despite this, the effects of dam removal on freshwater food webs are under-studied. Most existing studies investigate the impacts on fish assemblages, and very few investigate the impact on diatom, crayfish, and turtle communities. Furthermore, low-head dams are more abundant than large hydropower dams, yet the impacts of their removal are less studied than their larger counterparts. I used a Before After Control Impact (BACI) study design to survey populations of benthic diatoms, riffle-dwelling crayfish, and aquatic turtles. Species richness, species evenness, and Shannon Diversity Index values were used to …

Enabling Sustainability Transitions For Great Salt Lake: Framing Of Public Opinion, Boundary Work, And Policy, Anna Mcentire

All Graduate Theses and Dissertations, Fall 2023 to Present

This dissertation explores how people think about, talk about, and take action to save Great Salt Lake, which reached historic low levels in 2021. Using surveys, public records, and legislative documents primarily from 2022 to 2024, the research examines public opinions, collaborative efforts, and policy changes related to the lake. The first chapter looks at what people value about the lake and what actions they want to see taken. It finds that people are very concerned and want significant efforts to stop the lake's decline. The second chapter investigates how different groups work together publicly to negotiate new understandings, create …

Machine Learning Applications For Evaporation Predictions From Small Reservoirs: Potential Water Savings For Lower Rio Grande Valley, Texas, Syed Muhammad Fahad Abdullah

Theses and Dissertations

Local-scale reservoirs are important to regional water balance, but these are often overlooked. This study presents a robust machine learning (ML) approach leveraging reanalysis datasets to estimate daily evaporation for local-scale reservoirs in semi-arid South Texas. Selected models were trained with daily lake evaporation model (DLEM) estimates and used climatic and reservoir-specific properties as feature input variables. The multi-reservoirs training approach ensured applicable model generalization. Results show promising predictive performance with R² values ranging from 0.55–0.67 (testing) and 0.64–0.78 (validation), NSE values ranged from 0.54 0.67 (testing) and 0.64–0.78 (validation), and RMSE values ranged between 1.52–1.80 mm/day (testing) and 1.22–1.58 …

Reducing Single-Use Plastic In Georgetown County, Alex Gaspar

Goal 12: Responsible Consumption and Production

No abstract provided.

Life Cycle Assessment Of The Cultivation Of Lettuce In A Hydroponic System Using The Nutrient Film Technique, Raquel Jordan

All Theses

Hydroponic systems are an emerging method of soilless crop cultivation typically done inside a greenhouse where nutrients are delivered dissolved in water rather than being supplied from the soil. Potential benefits of hydroponic systems include reduced irrigation requirements, higher crop yield per area, and the ability to grow crops year-round in nontraditional areas such as urban settings, cold climates, and sites with contaminated soil. However, hydroponic systems tend to have high energy requirements for lighting and climate control, which can yield significant environmental impacts. To explore the environmental impacts of cultivating lettuce in a nutrient film technique (NFT) hydroponic system, …

Small Stream Restoration In The Piedmont Of South Carolina: Comparison Of Evaluation Tools And Water Quality’S Effects On Salamanders, Camryn Lachica

All Theses

For many years, the United States Army Corps of Engineers (USACE) used the Guidelines for Preparing a Compensatory Mitigation Plan worksheets to guide pre-restoration evaluation and determine post-restoration mitigation credits in South Carolina. Recently, the USACE in South Carolina transitioned to the Stream Quantification Tool (SQT), which provides a more comprehensive assessment framework. Our first objective was to compare these assessment methodologies across different landscape types to determine what the SQT adds to mitigation calculations that were not considered in prior worksheets. We evaluated 16 streams in the Piedmont of South Carolina, with four replicates each of forested, suburban, urban, …

Heat Storage Using High Temperature Borehole Heat Exchangers, Jack Horvath

All Theses

The use of renewable energy sources such as wind and solar power is growing, and with it comes an increased need to store excess energy when it is generated and release it on demand. Moderate temperature thermal energy storage in the subsurface is widely used to heat buildings, but high temperatures, greater than 120℃, are required to power generators that convert stored heat to electricity. High temperature heat can be generated from solar collectors or other means and then transferred to the subsurface using borehole heat exchangers (BHE). A BHE consists of a closed-loop pipe system used to circulate a …

Enhancing The Value Of Satellite Earth Observations For Coastal Management: Tools For Collaboration And Co-Development, Nicole Dejeet Bartlett

Graduate Doctoral Dissertations

Despite unprecedented satellite Earth observation (EO) capabilities and free data availability, widespread adoption in coastal management remains limited due to persistent communication barriers between satellite experts and coastal practitioners. This dissertation addresses the fundamental challenge of translating satellite EO technical capabilities into management-relevant applications. Through synthesis of literature, stakeholder interviews, and two multi-year co-development case studies in Virginia's Middle Peninsula and Cape Cod, Massachusetts, this research identifies systematic barriers to satellite EO adoption and develops innovative frameworks for overcoming them.

The work argues for a common language between satellite product developers and coastal managers, identifying communication barriers spanning technical, institutional, …

Experimental Investigation Of Photovoltaic Soiling Losses And Aerosol Absorption And Scattering Related To Dust In The Chihuahuan Desert Region, German Rodriguez Ortiz

Open Access Theses & Dissertations

This dissertation explores the interaction between mineral dust and solar radiation in the Chihuahuan Desert, one of the dustiest areas in North America. I focused on two main aspects: (1) the characterization of atmospheric aerosol optical properties during dust events, and (2) the effects of dust deposition (soiling) on the performance of photovoltaic (PV) modules. I characterized the intrinsic optical properties of aerosols in El Paso, Texas during the peak of the 2021 dust season. Ground-level, high-resolution optical and meteorological data were collected at the Black and Brown Carbon (BC^2) study site, whereas particulate matter and additional meteorological parameters were …

Development And Evaluation Of Supported Ionic Liquid Membrane And Porphyrin Frameworks For Carbon Capture Separation, Sarang Ismail

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The global urgency to mitigate anthropogenic CO₂ emissions has intensified the pursuit of energy-efficient separation technologies. Supported Ionic Liquid Membranes (SILMs) have emerged as promising candidates for CO₂ capture due to their tunable solubility-selectivity and low energy requirements. However, challenges such as mechanical instability, limited scalability, and trade-offs in transport performance have impeded their widespread adoption.

This thesis explores a systematic approach to designing and optimizing SILMs for enhanced CO₂ separation by tailoring polymer–ionic liquid interactions, processing conditions, and material architectures. A comprehensive set of studies were conducted using poly(vinylidene fluoride) (PVDF) with varying molecular weights, different grades of PEBAX®, …

Mixture Effects On Metal Accumulation In The Asian Clam, Corbicula Fluminea, Mark A. Huff

Electronic Theses and Dissertations

Field collected Corbicula fluminea were exposed to trace level copper, lead, and zinc with the aim of examining the preferential accumulation between the soft tissue and shell. Metal levels were based on those in a permitted industrial effluent. At 1X effluent and 2X effluent exposure levels, copper was found to preferentially accumulate in the clam soft tissue, lead was found to preferentially accumulate in the clam shell, and zinc was found to excrete back into the diluent after preferentially accumulating in the clam soft tissue. When exposed as a mixture at 1X effluent levels, copper and lead were found to …

Multi-Crop Systems And Crop-Switching Strategies To Enhance Water Use Efficiency And Climate Resilience In Arid Agricultural Regions, Shahryar Fazli, Wenzhao Li, Surendra Maharjan, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Agriculture in the Lower Colorado River (LCR) region faces mounting challenges from climate change, arid conditions, and water scarcity. This study evaluates water use efficiency (WUEc) and crop-switching strategies under SSP2-4.5 and SSP5-8.5 scenarios for 2025–2049, 2050–2074, and 2075–2099. Using historical data, climatic drivers such as temperature and precipitation were analyzed for their influence on key crops, including durum wheat, winter wheat, and corn. Results show SSP2-4.5 supports water use reductions up to 16%, stable profits (80–90%), and modest calorie increases (up to 15%), while SSP5-8.5 poses severe challenges, with water use reductions of 2–5%, profits dropping to around 20%, …

Exploring Biotic And Abiotic Drivers Of Ecosystem Properties: The Influence Of Waterbirds And Photodegradation On Wetland Ecosystems, Lindsay Miller

All Graduate Theses and Dissertations, Fall 2023 to Present

Wetlands provide a wide range of valuable ecosystem services: these are benefits from the environment that support human well-being, such as water filtration, fish and bird habitat, and shoreline protection. Despite their importance, wetlands are among the most threatened ecosystems, facing increasing pressure from natural and human activities. To better predict the future of wetlands and guide effective management and restoration practices, we need to understand the various forces shaping their ecological properties. In this thesis, we examined the influence of two forces: waterbirds and photodegradation (the process by which sunlight breaks down plant material). To explore each of these …