Digital Commons Network^™

Soil Health In Nebraska: Exploring Practitioners' Needs And Insights From A Long-Term Organic Farm, Ingrids Isabel Mata Vigil

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Soil health is foundational to sustainable agriculture, environmental resilience, and long-term food security. Yet, the adoption of soil health assessments remains limited, often perceived as too technical, costly, or difficult to implement in real-world contexts. To better understand these challenges, the first chapter presents findings from a statewide survey of 41 soil health practitioners in Nebraska, including farmers, extension educators, NRCS staff, and conservation professionals. Respondents highlighted the need for simpler, more accessible, and context-specific tools for soil health assessment that help practitioners make informed decisions aligned with their management goals. Complementing these insights, the second chapter includes an independent, …

Investing Hysteresis In Floodplain Dynamics Of Lakes In The Middle St. Johns River Using Sentinel-1 Sar Imagery, Keenan Hubbard

Doctoral Dissertations and Master's Theses

Floodplain dynamics are often complex, with hysteresis potentially affecting the temporal relationship between flood stage and flood extent during subsequent inundation phases. This study leverages Sentinel-1 synthetic aperture radar (SAR) imagery to map flood extent in the Middle St. Johns River Lake floodplains and examine the presence of hysteresis during flood events. SAR scenes corresponding to river gauge readings were analyzed from the rising and falling limbs of a flood hydrograph. By comparing these flood maps, we assess differences in inundated areas at equivalent water levels during each stage of the flood event. The findings aim to enhance flood monitoring …

Sensor Lag Adjustments On A Mobile Meteorological Cart In Tropical Environments: A Case Study From An Urban Park In Singapore, Moshe Eliezer Mandelmilch, Sin Kang Yik, Beatrice H. Ho, Graces N. Y. Ching, Peter J. Crank, Winston T. L. Chow

Research Collection College of Integrative Studies

This study adds to the growing literature on mobile platforms by examining the performance of the Singapore MaRTy (SMaRTy) in conducting mobile micrometeorological measurements along a designated route in an urban park in Singapore, reflecting a pedestrian walking experience. The main objective of the study was to calculate the sensor lag for the mobile climate measurements: Air Temperature (TA), and Relative Humidity (RH) of SMaRTy along a designated route in an urban park in Singapore based on data from fixed stations (HOBO sensors) in two significant synoptic meteorological periods during the Northeast and Southwest monsoons. Statistically significant regression models were …

Status Of The Western Australian Pastoral Rangelands 2024: Total Vegetative Cover, Cover Risk And Pasture Condition, Department Of Primary Industries And Regional Development, Western Australia

Natural resources published reports

The Department of Primary Industries and Regional Development (DPIRD) monitors and reports on the vegetation condition of pastoral rangelands in Western Australia. Two levels of reporting are provided: every 5 years a full report (this report) details the state, trend and risk of decrease of vegetation condition in the pastoral rangelands using information derived from remotely sensed and on-ground data; in the intervening years, short reports are provided based on remotely sensed data.

This full report is based on remotely sensed vegetation cover data, rainfall data, livestock data and station-level rangeland condition assessment (RCA) data available in November 2024. Data …

Energetic And Economic Aspects Of Rebound, Part Ii: Applications Of The Framework, Matthew Kuperus Heun, Gregor Semieniuk, Paul Brockway

University Faculty Publications and Creative Works

Widespread implementation of energy efficiency is a key greenhouse gas emissions mitigation measure, but rebound can ‘‘take back’’ energy savings. However, the absence of solid analytical foundations hinders empirical determination of rebound magnitudes. In Part I, we developed foundations of a rigorous, analytical, consumer-sided rebound framework that is approachable for both energy analysts and economists. In this paper (Part II), we develop energy, expenditure, and consumption planes, a novel, mutually consistent, and numerically precise way to visualize and illustrate rebound. Further, we operationalize the macro factor (k) for macroeconomic rebound. Using the framework and rebound planes, we calculate and show …

Response Of Soybean To Variable Irrigation Levels In Eastern Nebraska Using The Aquacrop Model, Anmol Singh

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

AquaCrop was calibrated and validated for soybean [Glycine max (L.) Merr.] using 19 irrigation treatments from five years using data from field experiments. The model accurately simulated canopy cover (CC), soil water content (SWC), and grain yield, with overall validation nRMSE values of 12%, 7%, and 7%, respectively. The overall validation nRMSE for SWC in individual 30-cm soil layers was comparatively higher, at 19%. The model was subsequently applied for long-term simulations (2010–2024) to estimate soybean yield and water requirements for two dominant soil types, Yutan silty clay loam and Tomek silt loam under three irrigation levels - rainfed, …

Feasibility Of Using Recycled Waste Plastic In Concrete Pavements In Nebraska, Amasi Hajahja

Department of Construction Engineering and Management: Dissertations, Theses, and Student Research

Waste plastic (WP) is a growing environmental concern due to its non-biodegradable nature, large-scale production, and harmful impact on natural resources. With nearly 75% of WP in the United States ending up in landfills, effective recycling strategies are urgently needed. In parallel, the limited availability of natural aggregates highlights the need for alternative materials in concrete construction. This study investigates the feasibility of using recycled waste plastic (RWP) in concrete mixtures, both as aggregates and fibers for rigid pavement applications in Nebraska. Concrete mixtures were prepared by partially replacing natural fine aggregates with recycled plastic aggregates (RPA) at replacement levels …

A Study Of Ice And Fire: Environmental Change Impacts On Lakes Of The Nebraska Sandhills, Daniel Gschwentner

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

The Nebraska Sandhills contain thousands of shallow, groundwater-fed lakes. These lakes are extremely sensitive to environmental and climatic changes due to their isolated hydrological setting and small volume. Building on previous work on the hydrology, geochemistry and long-term climate response of Sandhill lakes, my research considers how ecosystem processes such as primary production, nutrient limitation and water quality respond to short-term environmental and climatic change. In my first data chapter, I highlight that Sandhill lakes are nitrogen (N) but not phosphorus (P) limited and that N:P ratios are poor predictors of nutrient limitation status in Sandhill lakes. In my second …

Catching A Fever: A Comparison Of Vachellia Xanthophloea Populations In The Limpopo And Luvuvhu River Floodplains Of The Makuleke Contractual Park, Kianie B. David

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

This study investigates patterns of stand structure regeneration, growth characteristics, and coarse woody debris (CWD) patterns in Vachellia xanthophloea (fever tree) stands within the Makuleke Contractual Park (MCP), a semi-arid savanna system in northern Kruger National Park (KNP), South Africa. Fieldwork was conducted across two stand types: a monospecific fever tree stand in Rietbok Vlei and a mixed-species stand in the Western Nhlangaluwe Floodplain where fever tree is established with Faidherbia albida (ana tree). Data were collected from 20 total 1/4-acre (1,011 m²) circular plots between both stands in 2024 and 2025, including seedling root collar diameter (RCD), …

Bioenergy Crop Production: Implications For Grassland Bird Communities In Southwestern Nebraska, Grace E. Schuster

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

Biofuel and bioenergy systems are components of most climate stabilization pathways to reduce greenhouse gas emissions and limit global warming. Currently, corn (Zea mays) is the predominant feedstock used for bioenergy production in the United States. However, widespread production of this monoculture crop has resulted in many negative environmental impacts. The most notorious impact has been the loss of grassland habitat due to agriculture expansion which has had detrimental effects on wildlife that depend on grassland habitat. One such group, grassland birds, has faced steeper, more consistent, and more widespread declines than any other avian guild. Therefore, strategies …

The Surface Water And Ocean Topography (Swot) Mission For River And Lake Ice Application, Sunwoo Yoon

Earth Sciences Theses and Dissertations

The Surface Water and Ocean Topography (SWOT) mission, launched in December 2022, is designed for global survey of Earth’s surface water. However, the seasonal freezing of lakes and rivers combined with SWOT’s unique interferometric radar characteristics presents a valuable opportunity to assess its potential for river and lake ice applications. In this dissertation, I first compare backscatter characteristics over open water and frozen lakes and rivers. I demonstrate strong contrast in backscatter between water and ice while accounting for incidence angle, highlighting SWOT’s capability to discriminate between surface cover types. However, overlapping backscatter signatures suggest further investigation of drivers of …

Electrochemistry Behind Pfas: Mechanistic And Analytical Approach For Sensing And Degradation Strategies, Jonathan Josue Calvillo Solis

Open Access Theses & Dissertations

Understanding the fundamental electrochemistry of perfluoroalkyl substances (PFAS) is key to developing effective water remediation and sensing strategies. This work explores the thermodynamics and kinetics of perfluorooctanoic acid (PFOA) electroreduction, focusing on C-F bond cleavage. These insights were applied to design a highly sensitive electrochemical sensor for detecting trace levels of PFOA in water. This dissertation focuses on the electrochemical investigation of the reduction reaction of PFOA in aqueous and organic media employing different electrode materials. This exploration allows to understand the defluorination reaction of PFAS to further propose potential strategies for water treatment and PFOA electrosensing. Through electrochemical, spectroscopical …

Expanding And Mainstreaming Sociohydrology Toward Transdisciplinary Praxis, Shinichiro Nakamura, Heidi Kreibich, Melissa Haeffner, Jenia Mukherjee, Giuliano Di Baldassarre, Maiko Sakamoto, Mikiko Sugiura, Günter Blöschl, Taikan Oki, Murugesu Sivapalan

Environmental Science and Management Faculty Publications and Presentations

Since its development in the early 2010s, sociohydrology has deepened our understanding of the long-term coevolution of humans and water by integrating insights from both the natural and social sciences, while also fostering an interdisciplinary community. Its modus operandi to date has been to focus on emergent phenomena, manifesting as unintended consequences, in a variety of contexts. The compound disaster that struck Japan’s Noto Peninsula in 2024, and similar experiences in other parts of the world, underscore the urgent need for systemic approaches that are co-developed by academia and practitioners and focus on context-specific solutions. This perspective piece thus calls …

Electrocatalytic Degradation Of Methylene Blue Using Graphene Oxide, Antimony Oxide, And Graphene Oxide-Supported Antimony Oxide Ink-Based Electrodes, Maria Irene Myers Armas

Theses and Dissertations

This study investigates the electrocatalytic degradation of methylene blue (MB) using copper mesh electrodes coated with graphene oxide (GO), antimony oxide (Sb₂O₃), and their composite (GO/Sb₂O₃). These materials were evaluated across a pH range of 2 to 8 using sodium sulfate as the supporting electrolyte. UV-Vis spectroscopy at 665 nm confirmed dye degradation, with removal efficiencies reaching up to 95% at pH 2. However, degradation decreased at higher pH, with 40 – 60% removal at pH 8, depending on the electrode. Kinetic analyses revealed optimum performance under acidic conditions. GO/Sb₂O₃ electrodes demonstrated the most consistent and effective performance across all …

Political Ecologies Of Storage For The 21st Century, Sayd Randle, Matthew Archer

Research Collection College of Integrative Studies

New resource storage arrangements are proliferating rapidly both in terms of physical infrastructures-for the storage of things like "clean" energy, nuclear waste, carbon dioxide, fresh water, and data-and as part of a set of discursive moves that reinforce a vision of a near future world in which problems of climate change mitigation and adaptation in particular (but also issues like energy security, water security, industry growth, etc.) are solved through eco-modernist techno-fixes. This Symposium sketches the contours of a framework we term political ecologies of storage. In doing so, we treat storage as both a potent imaginary and a concrete …

Longitudinal Surveillance Of Aedes Aegypti (Diptera: Culicidae) In Urban Coastal Kenya: Population Dynamics, Blood Feeding Frequency And Dengue Virus Infection Rates, Josephine Osalla, Louis Clement Gouagna, Gilbert Rotich, Maureen Nzilani, Penina Safari, Kennedy Senagi, Francis Mutuku, Baldwyn Torto, David P. Tchouassi

All Peer-Reviewed Publications

The coastal region of Kenya has emerged as a focal point for urban dengue virus transmission driven by Aedes aegypti as the primary vector. To gain a deeper understanding of the epidemiological situation, we carried out a year-long longitudinal study (December 2021- November 2022) of the population dynamics of A. aegypti through weekly mosquito surveys using ovitrap and CO2-baited Biogents (BG) mosquito traps in Ukunda, an urban township in the coastal region. Aedes eggs laid in ovitraps were exclusively A. aegypti with 80.8% mean hatch rate. A total of 35,109 adult A. aegypti were captured, with twice as many females …

Enhancing Phenotyping Accuracy For Selection Of Urochloa Spp. Tolerant Genotypes To Red Spider Mite (Oligonychus Trichardti), Paula Espitia-Buitrago, José Miguel Cotes Torres, Luis Miguel Hernández, Juan Andres Cardoso, Frank Chidawanyika, Rosa N. Jauregui

All Peer-Reviewed Publications

The red spider mites are a major biotic limitation to productivity for Brachiaria (Urochloa spp.) grasses in tropical Eastern Africa, causing severe economic losses mainly in the dry seasons. However, due to the lack of reports of integrated pest management strategies, genetic resistance can play a crucial role in Brachiaria-based livestock systems, minimising the impact of this pest. The objective of this study was to develop and validate a methodology for accurately categorising resistance responses in Urochloa genotypes to identify potential sources of resistance to the Western Kenya red spider mite Oligonychus trichardti (Meyer 1974). Accordingly, 25 genotypes of Urochloa …

The Response And Recovery Of Carbon And Water Fluxes In Australian Ecosystems Exposed To Severe Drought, C. Stephens, B. Medlyn, L. Williams, J. Knauer, A. Inbar, E. Pendall, S. K. Arndt, J. Beringer, C. M. Ewenz, N. Hinko-Najera, L. B. Hutley, P. Isaac, M. Liddell, W. Meyer, C. E. Moore, J. Cranko Page, R. Silberstein, W. Woodgate

Research outputs 2022 to 2026

Climate change-driven increases in drought risk pose a critical threat to global carbon and water cycles. However, ecosystem-scale responses remain poorly quantified, particularly for severe, multiyear drought events. We addressed this gap by examining ecosystem-scale carbon and water flux sensitivity to the extreme 2018–19 drought in Australia using data from 14 eddy covariance flux sites. The ecosystems span grasslands and semi-arid woodlands to tropical and temperate forests. The driest sites (classed as “grass” and “very dry”) experienced drastic productivity impacts, with a 65% decrease in Gross Primary Productivity (GPP) over 2 years relative to the pre-drought average. However, fluxes in …

Winds Of Change: Charting A Pathway To Ecosystem Monitoring Using Airborne Environmental Dna, Rachel L. Tulloch, Clare I.M. Adams, Matthew A. Barnes, Elizabeth L. Clare, Henrik C. Van De Ven, Andrew Cridge, Francisco Encinas-Viso, Kristen Fernandes, Dianne M. Gleeson, Erin Hill, Anna J.M. Hopkins, Anna M. Kearns, Gracie C. Kroos, Anna J. Macdonald, Francesco Martoni, Angela Mcgaughran, Todd G.B. Mclay, Linda E. Neaves, Paul Nevill, Andrew Pugh, Kye J. Robinson, Fabian Roger, Tracey V. Steinrucken, Mieke Van Der Heyde, Cecilia Villacorta-Rath, Jenny Vivian

Research outputs 2022 to 2026

Airborne environmental DNA (airborne eDNA) analysis leverages the globally ubiquitous medium of air to deliver broad species distribution data and support ecosystem monitoring across diverse environments. As this emerging technology matures, addressing critical challenges and seizing key opportunities will be essential to fully realize its potentially transformative impact. In June 2024, the Southern eDNA Society convened over 100 researchers, industry leaders, and biodiversity management stakeholders in a landmark workshop to evaluate the current state of airborne eDNA research and chart a course for future development. Participants explored opportunities for integrating airborne eDNA into existing monitoring systems, but they unanimously agreed …

Source Origins Of Hunter-Harvested Waterfowl In Arkansas And Louisiana, Shannon C. Stemaly

LSU Master's Theses

Understanding variability in breeding origins of harvested waterfowl is important for effective population management and regional conservation. Band-recovery data are often used to estimate harvest derivation and inform resource allocation for cross-seasonal conservation. However, uneven spatial and temporal banding effort across species' breeding ranges may result in an incomplete understanding of summer origins and recruitment, particularly if portions of the breeding range are inaccessible. Analysis of stable-hydrogen isotope ratios in duck feathers (δ²H_f) provides an alternative method for identifying source origins of unmarked populations since environmental deuterium values follow a predictable latitudinal gradient across North …

Final Insufficiently Reclaimed Sites Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

How Invasive Species Affect Ecosystems, Marion Murray, Meg Kast

All Current Publications

Invasive species can have profound impacts on ecosystems worldwide. In the absence of their natural enemies, invasive species thrive and reproduce quickly. They can have significant ecological and economic effects. This fact sheet outlines the impact of invasive species on biodiversity, nutrient cycles, water quality, and the resulting economic consequences. It also suggests practical tips for responding.

Draft Final Quarterly Operations And Maintenance Report Butte Treatment Lagoon System – First Quarter 2025, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Butte Mine Flooding Operable Unit Berkeley Pit And Discharge Pilot Project – May 2025 Monthly Discharge Monitoring Report, Mark Thompson, Dave Griffis

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

A Demand Systems Analysis Of Energy Sources In The United States, Rafael Bakhtavoryan

Faculty Publications

This study estimates a Generalized Exact Affine Stone Index model to quantify demand structure among such energy sources as natural gas, coal, nuclear, wind, solar, and geothermal energy, employing monthly time-series data ranging from January of 2009 through December of 2020. The demand for natural gas, coal, and nuclear energy emerges as inelastic. A significant substitutability relationship is empirically established between the energy sources. All the computed expenditure elasticities are positive, with natural gas being the most sensitive and nuclear energy being the least sensitive to energy source expenditures. Pre-committed consumption is found for geothermal energy. Finally, the welfare implications …

Digital Infrastructure For The Regenerative Movement: A Case Study Of The Mycelium Learning Network, Abigail Karparis

Journal of Nonprofit Innovation

The regenerative movement is gaining momentum worldwide, driven by communities working to restore ecological and social systems through place-based, culturally rooted action. Yet many of the groups leading this work, especially in the Global South or in hyper-local contexts, remain digitally invisible due to structural barriers, including limited access to appropriate technology, funding constraints, and misalignment between available tools and local values. Conventional digital infrastructures often exclude or marginalize these efforts, leaving regenerative practitioners disconnected from each other and from potential sources of support.

This article explores these challenges and presents a case study response: the co-creation of accessible, relational …

Western Australia's Marine Heatwave Update - 27 June 2025, Department Of Primary Industries And Regional Development, Western Australia, Arani Chandrapavan

Marine Heatwave Notification Reports

No abstract provided.

A Battle Of Armies: Massive Attack Of Natural Enemies To The True Armyworm Mythimna Unipuncta (Haworth, 1809) (Lepidoptera: Noctuidae) In Forage Crops, Armando Falcon-Brindis, Raul T. Villanueva

Insecta Mundi

Understanding the interactions between plant-host-parasitoid plays a major role in insect pest management. Farmers in the southeastern United States rely on pasture systems for cattle milk and beef production, but the benefits of parasitoids and predators on major lepidopteran pests on pasture lands are still overlooked. Here, we aimed to identify and quantify the effect of parasitism on the true armyworm Mythimna unipuncta (Haworth, 1809) (Lepidoptera: Noctuidae) attacking teff grass Eragrostis tef (Zucc.) Trotter (Poaceae) and crabgrass Digitaria sanguinalis (L.) Scop. (Poaceae) in western Kentucky. In early August of 2023, 547 larvae of M. unipuncta were collected from experimental …

Power Optimized Co-Registration Of Multispectral And Thermal Cameras For Real-Time Urban Pluvial Flood Monitoring, Fatemeh Rezaei

Theses - ALL

Urban pluvial flooding occurs when local precipitation intensity exceeds the capacity of natural and engineered drainage systems, resulting in dangerous and highly localized inundation that is not captured by traditional stream gaging networks. While satellite imagery and flood maps support regional-scale flood management, a critical gap remains in the real-time, spatially continuous, in-situ monitoring of urban surface flooding. To address this monitoring gap, we develop a low-power, camera-based distributed sensor network flood mapping platform, Urban Flood Observation Network (UFO-Net), featuring two co-mounted sensors: a multispectral optical (capturing RGB and Near-Infrared) and a long-wave infrared (thermal) camera. A five-band image (RGB, …

Regional Groundwater Flow And Advective Contaminant Transport Modeling In A Typical Hydrogeological Environment Of Northern New Jersey, Toritseju Oyen, Duke Ophori

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

This study develops a numerical model to simulate groundwater flow and contaminant transport in a “typical hydrogeological environment” of northern New Jersey, addressing freshwater decline. Focusing on the Lower Passaic water management area (WMA), we model chloride transport in a fractured-rock aquifer, where fracture networks control hydraulic conductivity and porosity. The urbanized setting—encompassing Montclair State University (MSU) and municipal wells—features heterogeneous groundwater systems and critical water resources, providing an ideal case study for worst-case contaminant transport scenarios. Using MODFLOW and MODPATH, we simulated flow and tracked particles over 20 years. Results show that chloride from MSU reached the Third River …