Bioresource and Agricultural Engineering Commons^™

Cultivation Of Botryococcus Braunii For The Production Of Hydrocarbons Suitable For Fuel Use, Bryan C. Carroll

All Theses

Energy security, rural poverty, and climate change are pressing issues of our time. Biofuels provide a solution to these issues, with a focus on sustainable aviation fuel, SAF, due to compatibility with aircraft infrastructure and energy density. This research aims to review and produce knowledge about a specific microalga, Botryococcus braunii, for its potential for SAF. First a literature review on the process was conducted followed by an experimental study on the impact of aqueous media and inorganic carbon its growth and hydrocarbon content. The literature review found the process consists of cultivation followed by lipid extraction or hydrothermal …

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 …

Biological Hydrogen Process Improvements By High Temperature Simultaneous Saccharification And Fermentation, Frank W. Jeffries V

All Theses

The hyperthermophilic bacterium Thermotoga neapolitana is established as a versatile organism for fermentative hydrogen (H₂) production. Batch experiments were carried out to investigate the cell yield, product yield, and kinetic parameter values for individual media containing five carbohydrates. The highest H₂ yield of 15.56±0.31 mmol-H₂/g-carbohydrate was reported for glucose medium. H₂ yield was measured to be 14.51±0.38, 14.44±1.15, 11.88±0.84, and 11.53±0.73 mmol/g for media containing xylose, cellobiose, arabinose and xylan respectively. Acetic acid yield followed a similar trend, where the obtained values were 0.470±0.01, 0.462±0.04, 0.431±0.01, 0.409±0.03, and 0.406±0.01 g-acid/g-carbohydrate for glucose, cellobiose, xylose, …

Traditional Energy And Renewable Energy And Their Implications On Sustainable Development (Examples From Lebanon And The World), Radwan Ejel

Al Jinan الجنان

This study aims to introduce the types of fossil and renewable energies by presenting the various associated concepts. It shows their characteristics, in addition to the concept of sustainable development, to show the extent of traditional energy's repercussions on sustainable development and the role of renewable energies in promoting its concept through its three economic, social, and environmental dimensions. It also presents some statistical models on renewable energy, especially solar energy in Lebanon, the Arab world, and the world.

Previously, man used to invest in traditional fossil energy, such as oil, gas, and coal, to meet his economic and technological …

Groundwater Flooding On Highways In The Nebraska Sandhills: Applying Remote Sensing, Precipitation And Groundwater Modeling To Determine Depth, Cause And Frequency, Aaron R. Mittelstet

Nebraska Department of Transportation: Research Reports

Climate change significantly impacts infrastructure sustainability, particularly through shifts in precipitation patterns, intensity, and duration. These precipitation dynamics may increase the occurrence of surface water and groundwater flooding. Groundwater in the Nebraska Sand Hills (NSH), including the thickest portions of the High Plains Aquifer, extends close to the land surface in interdunal areas, making the NSH vulnerable to groundwater flooding. Recent events involving heavy precipitation, snow melt, and rising groundwater levels have caused prolonged highway flooding, disrupting transportation networks. This study estimates groundwater flood inundation depth, duration and frequency in the highways of NSH using remote sensing techniques and groundwater …

Geophysical Tools For Agricultural Management: Trends, Challenges, And Opportunities, Sophia Becker, Trenton Franz, Yufeng Ge, Joe Luck, Derek M. Heeren

School of Natural Resources: Faculty Publications

Agrogeophysics is a convergence of proximal soil sensing and hydrogeophysics in which geophysical methods are used to describe soil patterns and dynamics that shape agronomic management (including precision agriculture). To fully realize its potential for optimizing agricultural production, current barriers and targets for future agrogeophysics research must be identified. In this review, we compare the trajectory of agrogeophysics within peer-reviewed literature, patents, and the US university extension literature and examine the current challenges and opportunities for supporting agricultural production and sustainability with agrogeophysical tools. We conducted a repeatable search of Web of Science and Scopus for seven geophysical methods (electromagnetic …

Ai Tools In Natural Resources And Environmental Systems For The Classroom, Research, Extension And Industry, Derek M. Heeren, C. T. Agouridis, Debabrata Sahoo, Isaya Kisekka, Trisha L. Moore

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

This white paper synthesizes a series of panel insights on AI adoption across education, Extension, research and industry contexts within natural resources and environmental systems. It emphasizes that while advanced machine learning and generative AI introduce structural shifts in autonomy, scale, and cognitive augmentation, their value lies in augmenting, not replacing, human expertise. Applied tool examples include decision‑support systems for rural water operators, HAB‑diagnosis apps integrating image classification and natural‑language guidance, an irrigation educational chatbot tailored to user background, and sensor‑driven orchard AI for light interception estimation and data gap filling. A recurring design imperative involves co‑development with end users, …

Conservation Management Effects On Soil And Agronomic Properties In A Furrow-Irrigated Corn System In East-Central Arkansas, Jeferson P. Pimentel, Christopher G. Henry, Kris R. Brye, Benjamin R. Runkle, Amanda J. Ashworth, Edgar Mersiovsky, Kevin C. Thompson

Biological and Agricultural Engineering Faculty Publications and Presentations

Cover crops can improve soil physical properties and help to sustain agricultural crop yields. A 6-year study conducted from 2017 to 2022 examined the effects of conservation soil management practices in a furrow-irrigated continuous corn (Zea mays L.) system on a silt-loam soil (Typic Albaqualf) in the Lower Mississippi River Delta region of eastern Arkansas. This study compared the effects of conventional tillage (CT), no-tillage (NT), and no-tillage with cover crops (CC) in selected soil physical and chemical properties (i.e., soil bulk density (D b), porosity (& fnof;t), field capacity (Theta FC), Permanent wilting point (Theta PWP), Plant available water …

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, …

Legacy Nutrient Transport By Overland Sheet Flow, John E. Gilley, Ryan P. Mcgehee, Kenneth M. Wacha

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The transport of phosphorus (P) and nitrogen (N) from sites containing varying quantities of legacy nutrients was evaluated in this investigation. The data that were examined were collected during four previously reported field hydrologic studies performed in eastern Nebraska. Additional flow was introduced to the top of the rainfall simulation plots to replicate runoff conditions occurring along a hillslope. It was observed that both P and N delivery were influenced by runoff rate on sites where beef cattle manure or inorganic fertilizer had been applied. Legacy nutrient delivery appeared to have been influenced by the quantity of nutrients released at …

Fabrication Of A Pineapple Peeling Machine And Performance Evaluation As Influenced By Pineapple Dimensions, Dare E. Ibiyeye, Olusegun J. Adedipe, Oluwole S. Ariwoola, Taiye R. Afolabi, Funmilayo B. Okanlawon, Paul O. Ogunbamowo, Afolake E. Roberts

Journal of Bioresource Management

A pineapple peeling machine was completed, and the functionality was. The Central composite rotate strategy CCRD involving three variables at five (5) stages was employed for the investigations plus the investigational variables been weight, diameter and height of pineapple, while weights of peeled pineapple and peel, machine peeling time and efficiency were the dependent variables. Data was analysed using quadratic interaction regressions model at P ≤ 0.05 levels of significance, then the working variables were correlated to the pineapple machine peeling efficiency. The investigational outcomes were applied to confirm the predicted optimal settings. Maximal pineapple peeling efficacy of 91.89 % …

Nutrient Dynamics In Restored And Unrestored Urban Streams In The Piedmont Ecoregion Of South Carolina, Emily J. Jordan, Debabrata Sahoo, Calvin B. Sawyer, Jeremy W. Pike, Dara M. Park, Sarah A. White, Brian E. Haggard

Biological and Agricultural Engineering Faculty Publications and Presentations

The United States invests billions of dollars annually to perform stream restoration projects, yet few studies have investigated the effects this ecosystem manipulation has on nutrient cycling and associated water quality. Water quality improvement remains a substantial motivation for mitigating catchment-scale disturbances, especially in urban streams. Various urban land use practices impact the transfer and transport of nutrients such as soluble reactive phosphorus, ammonium, and nitrate plus nitrite from land into the streams and rivers. The uptake length (Sw), or the distance a dissolved nutrient travels downstream within a stream reach, can be measured using short-term nutrient injections, where shorter …

Farmnav-Uav: A Field-Ready Autonomous Uav For Tracking Static And Dynamic Trajectories In Agricultural Applications, Veera Venkata Ram Murali Krishna Rao Muvva

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

This study presents the design and development of a custom-built uncrewed aerial vehicle (UAV) tailored for precision agriculture. Unlike commercial UAVs, which are often constrained by proprietary systems and limited hardware customization, the proposed platform emphasizes modularity, upgradeability, and cost-effectiveness. The UAV is equipped with a Cube Blue flight controller for reliable low-level actuation and a Raspberry Pi 4 companion computer that executes a Model Predictive Control (MPC) algorithm for high-level trajectory optimization and stability enhancement.

Most conventional UAV autopilot systems rely on non-optimal control strategies, such as proportional–integral–derivative (PID) controllers, which can be inadequate for dynamic or resource-constrained environments. …

Integrating High Throughput Phenotyping Approaches To Characterize Plant Traits And Support Nutrient Management Research, Katie J. Bathke

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

Over the past decade, considerable research has addressed the social, economic, and agronomic challenges posed by imbalanced nutrient applications, particularly nitrogen and, more recently, sulfur. In response, high throughput plant phenotyping, as one of the latest approaches, has contributed to the development of innovative techniques for assessing key plant phenotypes under stress over time in both field and greenhouse environments. However, there is a limited number of studies applying these techniques for nutrient management, particularly in scenarios where two abiotic stressors coexist, such as the combination of water stress and nitrogen deficiency, or concurrent nitrogen and sulfur deficiencies.

In chapter …

Evaluating Nanobubble-Enriched Water Treatments For Cleaning Stainless Steel Winery Tanks At The Gallo Winery Research Station In Livingston, California, Edgar Godoy-Garcia

Master's Theses

ABSTRACT

Evaluating nanobubble-enriched water treatments for cleaning stainless steel winery tanks at the Gallo winery research station in Livingston, California.

Edgar A. Godoy-Garcia

Sanitation of stainless steel wine storage tanks is a critical component of quality control in commercial winemaking operations. Ineffective cleaning can lead to microbial contamination, product spoilage, and safety concerns. Traditionally, wineries rely on manual scrubbing, chemical cleaning agents, and extensive water rinsing cycles to maintain sanitary tank conditions. However, these methods are resource-intensive and may pose risks to both workers and the environment due to chemical exposure and wastewater generation. In response to growing industry interest …

Modeling Rice Leaf Area Index And Canopy Height In The Us Mid-South Region, Ellie J. Kuhn, Beatriz Moreno-Garcia, Michele Reba, Kusum Naithani, Benjamin R. Runkle

Biological and Agricultural Engineering Faculty Publications and Presentations

Crop growth modeling plays a critical role in addressing the global challenges of food scarcity, carbon cycling, and water management. By simulating crop development from environmental factors, these models help predict harvest yield and carbon or water cycle terms and thus can inform policy and investment decisions. However, for some agricultural regions, such as the US Mid-South, there is a lack of comprehensive data specific to rice (Oryza sativa) cultivars and their growing conditions. Here, we use 30 field seasons of observational data to predict leaf area index (LAI) and canopy height (Hcan), key inputs for crop growth models, for …

The Rapid Detection Of Foreign Fibers In Seed Cotton Based On Hyperspectral Band Selection And A Lightweight Neural Network, Yeqi Fei, Zhenye Li, Dongyi Wang, Chao Ni

Biological and Agricultural Engineering Faculty Publications and Presentations

Contamination with foreign fibers-such as mulch films and polypropylene strands-during cotton harvesting and processing severely compromises fiber quality. The traditional detection methods often fail to identify fine impurities under visible light, while full-spectrum hyperspectral imaging (HSI) techniques-despite their effectiveness-tend to be prohibitively expensive and computationally intensive. Specifically, the vast amount of redundant spectral information in full-spectrum HSI escalates both the system's costs and processing challenges. To address these challenges, this study presents an intelligent detection framework that integrates optimized spectral band selection with a lightweight neural network. A novel hybrid Harris Hawks-Whale Optimization Operator (HWOO) is employed to isolate 12 …

Nasa Design And Analysis Of Pegda Hydrogels For Microgreen Cultivation In Space, Fabiha Samiha, Luis E. Luna, Kelly Wu, Gabriel Antigua, Artur Abramyan

Publications and Research

Through multiple experiments, Polyethylene Glycol Diacrylate (PEGDA), a biocompatible polymer, has shown potential as a soilless growing medium for microgreens like arugula. However, a challenge arises when the roots run out of space within the hydrogel capsule, pushing the plant out of position and preventing it from absorbing nutrients from the PEGDA.

This study aims to address this challenge by analyzing different 3D-printed mold designs for the creation of the hydrogel capsules. The most promising designs include coil and tree-branch models, which encourage roots to grow in a way that relieves pressure on the leaf side of the plant, helping …

The Effect Of Boom Leveling On Spray Dispersion, Miguel Bustamante, Juan F. Vivanco, Travis A. Burgers

Mechanical Engineering Faculty Publications

Automatic boom height systems reduce the variability of agricultural sprayer boom height. When a boom is not at its target height, this can lead to uneven spray dispersion from the nozzles. Boom heights and sprayer position were previously measured in time for three commercially-available boom leveling systems for three test runs for at least three speeds over each of a mild, medium and rough terrain course. A computational model was created to use measured spray dispersion from a nozzle, measured boom heights in time, and measured sprayer position in time to calculate a spray coverage map. The model was used …

Autonomous Agricultural Equipment Evaluation For Broad-Acre Crop Production, Sofia Bahmutsky, Ashutosh Singh, Travis A. Burgers, Roy Maki

Mechanical Engineering Faculty Publications

No abstract provided.

Engineering Planktonic And Biofilm Microalgae Systems For Productivity, Power Requirements, Cost, And Scalability, Dallin Chugg

All Graduate Reports and Creative Projects, Fall 2023 to Present

Microalgae cultivation offers dual benefits as an effective wastewater treatment method and a sustainable source of valuable bioproducts, such as biofuels, bioplastics, and feedstocks. This approach supports sustainability by transforming waste into high-value products while minimizing environmental impact. However, scaling microalgae cultivation to industrial levels presents significant challenges, particularly in optimizing harvesting efficiency, reducing mixing and transport costs, and managing large water requirements.

This report compares the productivity, scalability, cost, and energy requirements of two primary cultivation systems: planktonic and biofilm. Planktonic systems, such as open raceway ponds (ORPs), excel in light distribution and nutrient uptake due to continuous mixing, …

Sustainable Agriculture Through Data-Driven Land And Soil Management For Rural Farming Communities, Peggy Clareece Discenza

Open Access Theses & Dissertations

This thesis aims to investigate sustainable farming practices by utilizing a database containing soil, weather, and water data. Additionally, it evaluates cropping strategies using a system that incorporates nutrient dynamics and environmental values. The objective is to monitor, develop predictive models, and assess the impact of both controlled and uncontrolled nutrient variables. This is achieved through the development of an algorithm that provides information on soil health based on datasets and land use, with a particular focus on residual values after harvesting for deeper analytical insights and interpretation. This study focuses on key nutrients, including pH levels, water availability, and …

Connecting Biological Engineering Education With Hands-On Internship Experience, Lindsey Bush

Biological and Agricultural Engineering Undergraduate Honors Theses

My honors thesis examines how my time in the biological engineering program and internship experience have prepared me for my future career. It highlights the skills I developed, the lessons I learned, and how these experiences shaped my job search and career decisions.

In my thesis, I share details about my internship. I described what I worked on, the places I visited, and the hands-on experience I gained. I talk about how my coursework provided a strong foundation and how my internship allowed me to apply those concepts in real-world engineering settings. I also discuss the technical and professional skills …

Assessing Sleep Quality In A Preclinical Model Of Low Back Pain Through Novel Noninvasive Methods, Lydia C. Saltz

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

Chronic low back pain (LBP) has widespread negative impacts on quality of life. Current treatments for chronic LBP fail to provide long-term efficacy and motivate the need to understand key drivers of poor patient outcomes. Mounting evidence indicates that sleep disturbances and chronic LBP have a strong reciprocal relationship. Women may be particularly vulnerable to the negative impacts of the sleep-pain axis, exhibiting greater prevalence in both conditions. However, the relationship between sleep, pain, and sex remains understudied. Preclinical models can be used to parse out characteristic sleep features that degrade with pain, which can be further broken out by …

Critical Analysis Of Coursework And Internship Experience In Relation To Biological Engineering At The University Of Arkansas, Samantha Wheat

Biological and Agricultural Engineering Undergraduate Honors Theses

My internship allowed me to gain important experience about a possible future career path with a biological engineering degree. Not only did this experience apply knowledge learned in the classroom from classes taken, I was also able to use my critical thinking skills gained from biological engineering coursework and teaching style to learn new skills and efficiently complete tasks given to me. This internship allowed me to try out a possible career path that interested me, and through my internship experience I was able to learn more about what kind of career path I was interested in after graduation. Additionally, …

Effects Of Sensor Separation On Flux Calculations In The Eddy Covariance Method., Maria D. Vergara Murillo

Biological and Agricultural Engineering Undergraduate Honors Theses

Rice production contributes approximately 8% of global anthropogenic methane emissions. Methane (CH₄) is a powerful greenhouse gas with a global warming potential 28 times greater than carbon dioxide (CO₂) which makes it important to monitor for understanding and mitigating its contribution to climate change. The Eddy Covariance (EC) method is used to monitor greenhouse gas emissions such as CO₂, CH₄, etc. As part of the EC method, the instruments on the EC towers are used to record the gas concentrations in the atmosphere; these concentrations are then run in the EddyPro software …

A Case Study On Readiness Of Engineers In Agricultural Technology Start-Ups, Katie Marie Mowat

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

This dissertation explores the perceptions of practicing engineers regarding the skills necessary to be workforce-ready at agricultural technology (ag-tech) start-ups in the Midwestern United States. A qualitative case study methodology is leveraged, combining both interview and job description data. Given their uniqueness, the study divides the ag-tech start-up industry into two subcases: livestock and cropping systems. The Work Readiness Integrated Competence Model (WRICM) is used as the theoretical framework for this study and informs the conceptual framework and analysis processes. The study identified skills that fit into thirteen distinct categories, which are further grouped into four overarching resource groups. Skills …

Optimizing Nitrogen Management: Assessing Nitrate Transport In The Deep Vadose Zone And Its Impact On Groundwater Quality In East-Central Nebraska, Muili O. Lawal

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

Groundwater contamination by nitrate (NO₃-N) is a growing environmental and public health concern driven largely by intensive agricultural fertilizer applications. The vadose zone plays an important role in NO₃-N transport, influencing groundwater quality and agricultural sustainability. This study investigated NO₃-N leaching dynamics in the deep vadose zone of Water Quality Sub-Area 30 (WQA30) within the Lower Loup Natural Resources District (LLNRD), northeast of Columbus, Nebraska (mean groundwater NO₃-N: 20.3 mg/L), using soil cores from 16 shallow (to 6.1 m) and four deep (down to 25.9 m) across four zones, two with inorganic fertilizer (Zones 1 and 4) and two with …

Berm-Leveling Machine For Peach Orchards: Incorporation Of Tree-Sensing Feature And Profitability Study, Shubham Singh

All Theses

Root collar excavation extends the productive life of peach trees in Armillaria root rot-infested soil, but the process requires trees to be planted on berms. Berm-planted peach orchards restrict the mobility of workers and machinery and can lead to increased erosion in furrows on either side of the berms. The current inter-tree berm-leveling machine depends on the driver's command to dodge the peach trees. The objectives of this thesis were to (1) integrate the feeler, infrared, and LiDAR-based tree sensing systems in the berm-leveling machine to make the soil excavating head's movement independent, (2) measure the impact of finger weeder-based …

Kinetic Growth Rate Analysis Of Coelastrella Sp. In Aquaculture Wastewater., Rob Skarvan

Master of Engineering Theses

The demand for sustainable food and energy production continues to rapidly rise. Utilizing aquaculture wastewater as microalgae growth medium is a potential opportunity for nutrient recycling and industrial symbiosis, but more research is required to understand how best to design and scale-up a dual-purpose facility. This study investigates the growth of Coelastrella sp. in aquaculture wastewater compared to industry-standard growth medium BG-11 and modified tap water as controls. Though cell size and pigment density varied throughout media, aquaculture wastewater performed very comparably to BG-11 as a microalgae culture broth.

The Monod equation can model Coelastrella sp. growth based …