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2020

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Full-Text Articles in Bioresource and Agricultural Engineering

Design Of A Deep Flow Technique Hydroponic System And An Elementary Education Module For Tri Cycle Farms, Cady Rosenbaum May 2020

Design Of A Deep Flow Technique Hydroponic System And An Elementary Education Module For Tri Cycle Farms, Cady Rosenbaum

Biological and Agricultural Engineering Undergraduate Honors Theses

Hydroponics is an agricultural technique in which plants are grown without soil and are instead grown in water systems that include nutrients and other growth-supporting media. Hydroponic systems typically reside inside, so that the system can be fully controlled by the grower by manipulating the temperature and amount of light the plants receive. The benefits of growing plants using hydroponics include: the amount of water used is reduced, it is less labor to grow organic produce with an indoor system, less space used, and it allows for growing food anywhere. Tri Cycle Farms is planning for the construction of a …


Reducing Dissolved Phosphorus In Stream Water May Not Influence Estimation Of Sediment Equilibrium Phosphorus Concentrations, Eleanor Henson May 2020

Reducing Dissolved Phosphorus In Stream Water May Not Influence Estimation Of Sediment Equilibrium Phosphorus Concentrations, Eleanor Henson

Biological and Agricultural Engineering Undergraduate Honors Theses

The potential for stream sediments to adsorb or release phosphorus (P) depends on the equilibrium P concentration (EPC), which is the water column P concentration where P is neither (net) adsorbed nor released from the sediments. Current methods of measuring EPC in streams include adding known P concentrations to stream water, mixing with fresh sediments, and allowing the mixture to reach equilibrium through P sorption. Sediment EPC is usually calculated as the x-intercept of the linear relationship between initial P concentrations and P absorbed by the sediments. However, the x-intercept is often an extrapolation past the known data set (i.e. …


Evaluation Of Low-Cost Depth Cameras For Agricultural Applications, Isabella C.F.S. Condotta, Tami M. Brown-Bandl, Santosh Pitla, John P. Stinn, Késia O. Silva-Miranda Apr 2020

Evaluation Of Low-Cost Depth Cameras For Agricultural Applications, Isabella C.F.S. Condotta, Tami M. Brown-Bandl, Santosh Pitla, John P. Stinn, Késia O. Silva-Miranda

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Low-cost depth-cameras have been used in many agricultural applications with reported advantages of low cost, reliability and speed of measurement. However, some problems were also reported and seem to be technology related, so understanding the limitations of each type of depth camera technology could provide a basis for technology selection and the development of research involving its use. The cameras use one or a combination of two of the three available technologies: structured light, time-of-flight (ToF), and stereoscopy. The objectives were to evaluate these different technologies for depth sensing, including measuring accuracy and repeatability of distance data and measurements at …


Sensitivity Analysis Of Data-Driven Groundwater Forecasts To Hydroclimatic Controls In Irrigated Croplands, Alessandro Amaranto, Francesca Pianosi, Dimitri Solomatine, Gerald Corzo-Perez, Francisco Munoz-Arriola Apr 2020

Sensitivity Analysis Of Data-Driven Groundwater Forecasts To Hydroclimatic Controls In Irrigated Croplands, Alessandro Amaranto, Francesca Pianosi, Dimitri Solomatine, Gerald Corzo-Perez, Francisco Munoz-Arriola

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In the last decades, advancements in computational science have greatly expanded the use of artificial neural networks (ANNs) in hydrogeology, including applications on groundwater forecast, variable selection, extended lead-times, and regime-specific analysis. However, ANN-model performance often omits the sensitivity to ob- servational uncertainties in hydroclimate forcings. The goal of this paper is to implement a data-driven modeling framework for assessing the sensitivity of ANN-based groundwater forecasts to the uncertainties in observational inputs across space, time, and hydrological regimes. The objectives are two-folded. The first objective is to couple an ANN model with the PAWN sensitivity analysis (SA). The second objective …


Biological Systems Engineering, Asmaa Abdella, Fernando Segato, Mark R. Wilkins Apr 2020

Biological Systems Engineering, Asmaa Abdella, Fernando Segato, Mark R. Wilkins

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The present work studied the optimization of aeration rate, agitation rate and oxygen transfer and the use of various batch fermentation strategies for xylanase production from a recombinant Aspergillus nidulans strain in a 3 L stirred tank reactor. Maximum xylanase production of 1250 U/mL with productivity of 313 U/mL/day was obtained under an aeration rate of 2 vvm and an agitation rate of 400 rpm using batch fermentation. The optimum volumetric oxygen transfer coefficient (kLa) for efficient xylanase production was found to be 38.6 h1. Fed batch mode and repeated batch fermentation was also performed with kLa was 38.6 h1. …


Evaluating Evapotranspiration Values In Rwanda While Using The Turc And Hargreaves–Samani Equations, Elizabeth Uwase, Derek M. Heeren, Lameck O. Odhiambo Apr 2020

Evaluating Evapotranspiration Values In Rwanda While Using The Turc And Hargreaves–Samani Equations, Elizabeth Uwase, Derek M. Heeren, Lameck O. Odhiambo

UCARE: Research Products

Evapotranspiration (ET) is an important component of the hydrologic cycle and involves the exchange of water between the surrounding water bodies, soil, crop surfaces, and the atmosphere. Crop growth and yields are largely affected by the rate of ET, especially in semi-arid areas where the rate of ET is high and rainfall is not sufficient and reliable to add more water into the soil for crop use. Solar radiation, relative humidity, air temperature, rainfall, and wind velocity are some of the meteorological factors that affect ET. Therefore, this research was aimed at determining ET and its trend across Rwanda using …


Resonant Metagratings For Spectral And Angular Control Of Light For Colored Rooftop Photovoltaics, Floris Uleman, Andrea Cordaro, Andrea Alù, Albert Polman Apr 2020

Resonant Metagratings For Spectral And Angular Control Of Light For Colored Rooftop Photovoltaics, Floris Uleman, Andrea Cordaro, Andrea Alù, Albert Polman

Advanced Science Research Center

We designed semitransparent metagrating supercells that enable control over the spectrum and directivity of incident light for applications in photovoltaics with tailored angular appearance. The building block of the supercells is a 100–120 nm wide and 175 nm tall silicon nanowire that shows a strong Mie resonance around λ = 650 nm. By arranging the resonant Mie scatterers into metagratings of increasing pitch (675–1300 nm), we created a Lambertian-like scattering distribution over an angular range of choice. The millimeter-sized metasurfaces were fabricated using electron beam lithography and reactive ion etching. The fabricated metasurface nearly fully suppresses specular reflection on resonance …


Investigating The Experimental Process For Partial Replacement Of Cement With Sugarcane Bagasse In The Construction Industry, Amany G. Micheal Prof., Rania Moussa, Nadin Dawoud Apr 2020

Investigating The Experimental Process For Partial Replacement Of Cement With Sugarcane Bagasse In The Construction Industry, Amany G. Micheal Prof., Rania Moussa, Nadin Dawoud

Centre for Advanced Materials

In the last few decades there has been speedily increasing in the agriculture and industrial wastes. This causes many environmental issues and raises the potential to contaminate the natural resources of living such as water, air and soil. Recently, the amount of organic waste produced daily has been rising, while it is poorly managed. It is either burned or disposed improperly, which effect negatively the environment and public health. On the other hand, during the cement production process many wastes, and pollutants are generated which have major negative impacts on the environment. Cement is considered as a substantial constituent of …


Assessment Of Nanoparticle Accumulation With Dynamic Contrast-Enhanced Magnetic Resonance Imaging, Hunter Miller Apr 2020

Assessment Of Nanoparticle Accumulation With Dynamic Contrast-Enhanced Magnetic Resonance Imaging, Hunter Miller

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

Nanoparticle (NP)-based therapeutics promise to improve medicine in multiple areas by increasing target engagement. To date, most research has focused on cancer, aiming to increase uptake using the enhanced permeability and retention (EPR) effect. Despite pre-clinical success in proof-of-concept studies, understanding of the fundamental interactions between NP and biological systems that govern outcomes remains incomplete. To realize the potential of NPs for cancer therapeutics, and to expand their application into other diseases, the roles physicochemical properties play in NP uptake must be better understood. Some investigations have been performed into the effects of size and surface charge on uptake into …


Maize Growth, Yield, Water Productivity And Evapotranspiration Response To Different Irrigation Methods And Amounts And Different Timing And Methods Of Nitrogen Applications, Ali T. Mohammed Apr 2020

Maize Growth, Yield, Water Productivity And Evapotranspiration Response To Different Irrigation Methods And Amounts And Different Timing And Methods Of Nitrogen Applications, Ali T. Mohammed

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

Declining the quantity and quality of freshwater resources in many parts of the world, including Midwestern USA, especially in the light of rapidly growing world’s population and changing climate, imposes significant and, in some cases imminent, challenges for producers, policy- and decision-makers to produce more yield with less water and other inputs, particularly in water scarcity regions.

There is not comprehensive previous research has quantified and evaluated coupled impacts of irrigation rates and nitrogen timing management strategies and their interactions on maize (Zea mays L.) productivity and its various attributed efficiency index metrics under different irrigation methods under the …


Fate And Transport Of Antibiotics And Antibiotic Resistance Genes In Runoff And Soil As Affected By The Timing Of Swine Manure Slurry Application, Renys Enrique Barrios, Himanshu Khuntia, Shannon L. Bartelt-Hunt, John E. Gilley, Amy M. Schmidt Schmidt, Daniel D. Snow, Xu Li Apr 2020

Fate And Transport Of Antibiotics And Antibiotic Resistance Genes In Runoff And Soil As Affected By The Timing Of Swine Manure Slurry Application, Renys Enrique Barrios, Himanshu Khuntia, Shannon L. Bartelt-Hunt, John E. Gilley, Amy M. Schmidt Schmidt, Daniel D. Snow, Xu Li

Department of Civil and Environmental Engineering: Faculty Publications

Land application of swine manure slurry is a common practice to supplement nutrients to soil for crop production. This practice can introduce antibiotic residues and antibiotic resistance genes (ARGs) into the environment. Field testing is critical in identifying manure management practices effective in minimizing the environmental impacts of manure-borne antibiotic and ARGs. The objective of this study was to determine how the timing of swine manure application relative to rainfall events impacts the fate and transport of antibiotics and ARGs in surface runoff and manure-amended soil. Swine manure slurry was either broadcast or injected on test plots in the field. …


Capturing Spatial Variability In Maize And Soybean Using Stationary Sensor Nodes, Jasreman Singh, Derek M. Heeren, Yufeng Ge, Geng Bai Apr 2020

Capturing Spatial Variability In Maize And Soybean Using Stationary Sensor Nodes, Jasreman Singh, Derek M. Heeren, Yufeng Ge, Geng Bai

Department of Agricultural and Biological Systems Engineering: Faculty Publications

• Irrigation in agriculture maximizes crop yield and improves food security globally • Irrigation scheduling is strongly based on the ability to accurately estimate the appropriate amount and timing of water application • The timing of the irrigation can best be informed through the crop canopy stress, and the amount of irrigation is informed through soil moisture depletion

• Developing upper (non-water stressed) and lower (non-transpiring) baselines for irrigated and non-irrigated maize and soybean • Investigating the relationship between the canopy stress and the soil moisture stress

The canopy temperature stress and soil moisture depletion had stronger correlation for non-irrigated …


Evidence Of Arithmetical Uncertainty In Estimation Of Light And Water Use Efficiency, Meetpal S. Kukal, Suat Irmak Dr. Mar 2020

Evidence Of Arithmetical Uncertainty In Estimation Of Light And Water Use Efficiency, Meetpal S. Kukal, Suat Irmak Dr.

Department of Agricultural and Biological Systems Engineering: Faculty Publications

It was demonstrated that conventional resource use efficiency (RUE) estimation methodology is largely subject to arithmetic weakness. Extensive field research data on aboveground biomass (AGB), absorbed photosynthetically active radiation (APAR), and crop evapotranspiration (ETc) in maize, soybean, sorghum, and winter wheat confirmed this methodological bias for light use efficiency (LUE) and water use efficiency (WUE) estimation. LUE and WUE were derived using cumulated (data aggregates across samplings) and independent (data increments across samplings) approaches. Use of cumulated data yielded strong-but-false correlation between AGB and APAR or Etc, being a statistical artefact. RUE values from an independent (data increments across samplings) …


Predicting Escherichia Coli Loads In Cascading Dams With Machine Learning: An Integration Of Hydrometeorology, Animal Density And Grazing Pattern, Olufemi P. Abimbola, Aaron R. Mittelstet, Tiffany Messer, Elaine D. Berry, Shannon L. Bartelt-Hunt, Samuel Hansen Mar 2020

Predicting Escherichia Coli Loads In Cascading Dams With Machine Learning: An Integration Of Hydrometeorology, Animal Density And Grazing Pattern, Olufemi P. Abimbola, Aaron R. Mittelstet, Tiffany Messer, Elaine D. Berry, Shannon L. Bartelt-Hunt, Samuel Hansen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Accurate prediction of Escherichia coli contamination in surface waters is challenging due to considerable uncertainty in the physical, chemical and biological variables that control E. coli occurrence and sources in surface waters. This study proposes a novel approach by integrating hydro-climatic variables as well as animal density and grazing pattern in the feature selection modeling phase to increase E. coli prediction accuracy for two cascading dams at the USMeat Animal Research Center (USMARC), Nebraska. Predictive models were developed using regression techniques and an artificial neural network (ANN). Two adaptive neuro-fuzzy inference system (ANFIS) structures including subtractive clustering and fuzzy c-means …


Banning Carbon Nanotubes Would Be Scientifically Unjustified And Damaging To Innovation, Daniel A. Heller, Prakrit V. Jena, Matteo Pasquali, Kostas Kostarelos, Lucia G. Delogu, Rachel E. Meidl, Slava V. Rotkin, David A. Scheinberg, Robert E. Schwartz, Mauricio Terrones, Yu Huang Wang, Alberto Bianco, Ardemis A. Boghossian, Sofie Cambré, Laurent Cognet, Simon R. Corrie, Philip Demokritou, Silvia Giordani, Tobias Hertel, Tetyana Ignatova, Mohammad F. Islam, Nicole M. Iverson, Anand Jagota, Dawid Janas, Junichiro Kono, Sebastian Kruss, Markita P. Landry, Yan Li, Richard Martel, Shigeo Maruyama, Anton V. Naumov, Maurizio Prato, Susan J. Quinn, Daniel Roxbury, Michael S. Strano, James M. Tour, R. Bruce Weisman, Wim Wenseleers, Masako Yudasaka Mar 2020

Banning Carbon Nanotubes Would Be Scientifically Unjustified And Damaging To Innovation, Daniel A. Heller, Prakrit V. Jena, Matteo Pasquali, Kostas Kostarelos, Lucia G. Delogu, Rachel E. Meidl, Slava V. Rotkin, David A. Scheinberg, Robert E. Schwartz, Mauricio Terrones, Yu Huang Wang, Alberto Bianco, Ardemis A. Boghossian, Sofie Cambré, Laurent Cognet, Simon R. Corrie, Philip Demokritou, Silvia Giordani, Tobias Hertel, Tetyana Ignatova, Mohammad F. Islam, Nicole M. Iverson, Anand Jagota, Dawid Janas, Junichiro Kono, Sebastian Kruss, Markita P. Landry, Yan Li, Richard Martel, Shigeo Maruyama, Anton V. Naumov, Maurizio Prato, Susan J. Quinn, Daniel Roxbury, Michael S. Strano, James M. Tour, R. Bruce Weisman, Wim Wenseleers, Masako Yudasaka

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In a recent correspondence, the Swedish non-profit organization ChemSec announced the addition of carbon nanotubes to the SIN (‘Substitute It Now’) list1. Carbon nanotubes were added as an entire material class that “should be restricted or banned in the EU.” We believe that this recommendation confuses researchers and the public as it is based on evidence from a very narrow subset of data. Such a designation will likely hinder innovations that could lead to safe and effective applications of carbon nanotubes. Furthermore, this line of reasoning could damage other fields of science and technology, if applied similarly. We have worked …


Thoroughbred Racehorse Welfare Through The Lens Of ‘Social License To Operate—With An Emphasis On A U.S. Perspective, Camie Heleski, C. Jill Stowe, Julie Fiedler, Michael L. Peterson, Colleen Brady, Carissa Wickens, James N. Macleod Feb 2020

Thoroughbred Racehorse Welfare Through The Lens Of ‘Social License To Operate—With An Emphasis On A U.S. Perspective, Camie Heleski, C. Jill Stowe, Julie Fiedler, Michael L. Peterson, Colleen Brady, Carissa Wickens, James N. Macleod

Agricultural Economics Faculty Publications

This review addresses the question of whether Thoroughbred horse racing is sustainable in the context of current social values. A recently acknowledged framework, known as ‘Social License to Operate’ (SLO), provides us with a lens through which to view and assess racehorse welfare. In multiple surveys of the general public, the horse owning public, and university students, the primary topics of concern regarding Thoroughbred racing show considerable concordance: concern about catastrophic injuries—particularly as related to track surfaces, concern over the racing of two-year-olds, whip use by jockeys, drug/medication policies, and aftercare opportunities for retired Thoroughbred racehorses. Legitimacy of an industry, …


Dry And Wet Torrefaction Of Microalgal Biomass For Biochar Production As Bioenergy Sources, Yong Yang Gan Feb 2020

Dry And Wet Torrefaction Of Microalgal Biomass For Biochar Production As Bioenergy Sources, Yong Yang Gan

Student Works (2020-2029)

Increasing population in global and living standards have risen the consumption of global energy. Thermochemical conversion approaches hold great potential for the biomass conversion into energy applications. Among these approaches, torrefaction is a promising technique to enhance the biomass properties, making it more practical and suitable in biofuel applications. In this study, two different species of microalgae (third generation biofuel feedstock) including Chlorella vulgaris ESP-31 and FSP-E were used as feedstocks for dry and wet torrefaction. Dry torrefaction of microalgae was performed at temperatures of 200, 250 and 300 ºC, and holding times of 15, 30, 45 and 60 min, …


The Role Of Namibian Youth In The Advancement Of Sustainable Energy, Samantha Anne Lindgren Jan 2020

The Role Of Namibian Youth In The Advancement Of Sustainable Energy, Samantha Anne Lindgren

Link Foundation Energy Fellowship Reports

Across low- and middle-income countries (LMICs), 3.1 billion people cook and heat their homes by burning solid fuels such as firewood, charcoal, and crop and animal waste [1], [2]. Approximately 80% of rural communities in LMICs rely on biomass [3] for their energy needs. The emissions from these fires, including carbon monoxide and particulate matter, result in household air pollution (HAP) that cause both acute and chronic illnesses leading to nearly three million premature deaths each year [4]–[6], and are a leading producer of black carbon emissions, a key climate-forcing agent [7]. Efficient, or improved, cookstoves are an energy solution …


Volumetric Flow Measurement For Irrigation District Turnouts, Charles M. Burt, Daniel J. Howes, Stuart Styles Jan 2020

Volumetric Flow Measurement For Irrigation District Turnouts, Charles M. Burt, Daniel J. Howes, Stuart Styles

BioResource and Agricultural Engineering

Technical assistance related to irrigation district turnout flow/volumetric measurement is provided by ITRC on behalf of California Dept. of Water Resources, USBR, and BIA irrigation projects. Throughout that work, it was apparent there was a need to organize well-established information as well as to provide new insights into irrigation flow measurement. The target audiences are irrigation districts and others who want to improve measurement accuracy for irrigation flow rates and volumetric deliveries to meet regulations, improve the efficiency of ditchriders (system operators), and provide equity and transparency to farmers and managers. The focus of this publication is on turnouts (deliveries) …


Discharge Coefficients For Rectangular Suppressed And Submerged Sluice Gates, Charles M. Burt, Albert J. Clemmens, Kyle Feist Jan 2020

Discharge Coefficients For Rectangular Suppressed And Submerged Sluice Gates, Charles M. Burt, Albert J. Clemmens, Kyle Feist

BioResource and Agricultural Engineering

Two sizes of sluice gates were tested in submerged conditions with a variety of flow rates and gate openings. A new equation was developed for flow rate prediction.


Biotech Connector Brochure Jan 2020

Biotech Connector Brochure

Biotech Connector

The Biotech Connector represents an important opportunity to serve the economic needs of the people of Nebraska through further diversification of Nebraska's economy, and by helping forge and illuminate a pathway to jobs in the biotechnology space for Nebraska students.

The Biotech Connector is 7,700 sq. ft. of well-equipped wet-lab space located on Nebraska Innovation Campus. We provide incubation space and services to bioscience startups and high-growth biotech and research-based businesses.

Wet lab space provides aspiring startups and technology businesses with access to very expensive laboratory equipment that would be outside of the budget of most startups. Lack of access …


High‐ And Low‐Molecular‐Weight Chitosan Act As Adjuvants During Single‐Dose Influenza A Virus Protein Vaccination Through Distinct Mechanisms, Anna T. Lampe, Eric Farris, Deborah M. Brown, Angela K. Pannier Jan 2020

High‐ And Low‐Molecular‐Weight Chitosan Act As Adjuvants During Single‐Dose Influenza A Virus Protein Vaccination Through Distinct Mechanisms, Anna T. Lampe, Eric Farris, Deborah M. Brown, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The investigation of new adjuvants is essential for the development of efficacious vaccines. Chitosan (CS), a derivative of chitin, has been shown to act as an adjuvant, improving vaccine‐induced immune responses. However, the effect of CS molecular weight (MW) on this adjuvanticity has not been investigated, despite MW having been shown to impact CS biological properties. Here, two MW variants of CS were in- vestigated for their ability to enhance vaccine‐elicited immune responses in vitro and in vivo, using a single‐dose influenza A virus (IAV) protein vaccine model. Both low‐ molecular‐weight (LMW) and high‐molecular‐weight (HMW) CS‐induced interferon regulatory factor pathway …


An Assessment Of 2d And 3d Spatial Accuracy Of Photogrammetry For Livestock Health Monitoring, Luis Felipe Pampolini Jan 2020

An Assessment Of 2d And 3d Spatial Accuracy Of Photogrammetry For Livestock Health Monitoring, Luis Felipe Pampolini

Theses and Dissertations--Biosystems and Agricultural Engineering

The overall objective of this study was to evaluate the use of consumer-grade unmanned aircraft systems for image-based remote sensing in agriculture with application towards livestock health monitoring. A two-dimensional spatial error experiment was conducted to quantify the spatial accuracy of georeferenced orthomosaic imagery collected using a drone and processed with photogrammetry software. Treatment variables included altitude above ground level and image data type (visible and multispectral). The results from the ANOVA test indicated that there were significant differences between data types, but no significant differences between altitudes. The experiment was then expanded to a three-dimensional study where two life-size …


Predicting Escherichia Coli Loads In Cascading Dams With Machine Learning: An Integration Of Hydrometeorology, Animal Density And Grazing Pattern, Olufemi P. Abimbola, Aaron R. Mittelstet, Tiffany Messer, Elaine D. Berry, Shannon L. Bartelt-Hunt, Samuel Hansen Jan 2020

Predicting Escherichia Coli Loads In Cascading Dams With Machine Learning: An Integration Of Hydrometeorology, Animal Density And Grazing Pattern, Olufemi P. Abimbola, Aaron R. Mittelstet, Tiffany Messer, Elaine D. Berry, Shannon L. Bartelt-Hunt, Samuel Hansen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Accurate prediction of Escherichia coli contamination in surface waters is challenging due to considerable uncertainty in the physical, chemical and biological variables that control E. coli occurrence and sources in surface waters. This study proposes a novel approach by integrating hydro-climatic variables as well as animal density and grazing pattern in the feature selection modeling phase to increase E. coli prediction accuracy for two cascading dams at the US Meat Animal Research Center (USMARC), Nebraska. Predictive models were developed using regression techniques and an artificial neural network (ANN). Two adaptive neuro-fuzzy inference system (ANFIS) structures including subtractive clustering and fuzzy …


The Temporal And Spatial Dynamics Of Fluvial Carbon Cycling In Irish Blanket Peatland Pools And Soils, Mariya Radomski Jan 2020

The Temporal And Spatial Dynamics Of Fluvial Carbon Cycling In Irish Blanket Peatland Pools And Soils, Mariya Radomski

Doctoral

Blanket peatlands in Ireland are reservoirs of organic matter and have effects on carbon dioxide (CO2) flux regulation. Data on dissolved CO2 in Ireland is limited. In blanket peatlands, the drainage systems are well connected with pools, hummocks and lawns and this connectivity leads to significant variations in outflows of carbon. The excess carbon dioxide in blanket peatlands could originate from soil organic matter decomposition. Dissolved CO2 could be transported into pools via surface run-off and lateral throughflow. Peatland pools are typically supersaturated in CO2. As part of a project described in this thesis, the role of spatial and seasonal …


Irrigation-Yield Production Functions And Irrigation Water Use Effciency Response Of Drought-Tolerant And Non-Drought-Tolerant Maize Hybrids Under Different Irrigation Levels, Population Densities, And Environments, Suat Irmak, Ali T. Mohammed, William Kranz, C. D. Yonts, Simon Van Donk Jan 2020

Irrigation-Yield Production Functions And Irrigation Water Use Effciency Response Of Drought-Tolerant And Non-Drought-Tolerant Maize Hybrids Under Different Irrigation Levels, Population Densities, And Environments, Suat Irmak, Ali T. Mohammed, William Kranz, C. D. Yonts, Simon Van Donk

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Irrigation-yield production functions (IYPFs), irrigation water use effciency (IWUE), and grain production per unit of applied irrigation of non-drought-tolerant (NDT) and drought-tolerant (DT) maize (Zea mays L.) hybrids were quantified in four locations with different climates in Nebraska [Concord (sub-humid), Clay Center (transition zone between sub-humid and semi-arid); North Platte (semi-arid); and, Scottsbluff (semi-arid)] during three growing seasons (2010, 2011, and 2012) at three irrigation levels (fully-irrigated treatment (FIT), early cut-off (ECOT), and rainfed (RFT)) under two plant population densities (PPDs) (low-PPD; 59,300 plants ha-1; and, high-PPD, 84,000 plants ha-1). Overall, DT hybrids’ performance was …


Soil Structure And Texture Effects On The Precision Of Soil Water Content Measurements With A Capacitance-Based Electromagnetic Sensor, Jasreman Singh, Derek M. Heeren, Daran Rudnick, Wayne Woldt, Geng Bai, Yufeng Ge, Joe D. Luck Jan 2020

Soil Structure And Texture Effects On The Precision Of Soil Water Content Measurements With A Capacitance-Based Electromagnetic Sensor, Jasreman Singh, Derek M. Heeren, Daran Rudnick, Wayne Woldt, Geng Bai, Yufeng Ge, Joe D. Luck

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The physical properties of soil, such as structure and texture, can affect the performance of an electromagnetic sensor in measuring soil water content. Historically, calibrations have been performed on repacked samples in the laboratory and on in situ soils in the field, but little research has been done on laboratory calibrations with intact (undisturbed) soil cores. In this study, three replications each of disturbed and undisturbed soil samples were collected from two soil texture classes (Yutan silty clay loam and Fillmore silt loam) at a field site in eastern Nebraska to investigate the effects of soil structure and texture on …


An Automated Seepage Meter For Streams And Lakes, Douglas Kip Solomon, Eric Humphrey, Troy E. Gilmore, David P. Genereux, Vitaly A. Zlotnik Jan 2020

An Automated Seepage Meter For Streams And Lakes, Douglas Kip Solomon, Eric Humphrey, Troy E. Gilmore, David P. Genereux, Vitaly A. Zlotnik

Department of Agricultural and Biological Systems Engineering: Faculty Publications

We describe a new automatic seepage meter for use in soft bottom streams and lakes. The meter utilizes a thin‐walled tube that is inserted into the streambed or lakebed. A hole in the side of the tube is fitted with an electric valve. Prior to the test, the valve is open and the water level inside the tube is the same as the water level outside the tube. The test starts with closure of the valve, and the water level inside the tube changes as it moves toward the equilibrium hydraulic head that exists at the bottom of the tube. …


Prediction Of Neighbor-Dependent Microbial Interactions From Limited Population Data, Joon-Yong Lee, Shin Haruta, Souichiro Kato, Hans C. Bernstein, Stephen R. Lindemann, Dong-Yup Lee, Jim K. Fredrickson, Hyun-Seob Song Jan 2020

Prediction Of Neighbor-Dependent Microbial Interactions From Limited Population Data, Joon-Yong Lee, Shin Haruta, Souichiro Kato, Hans C. Bernstein, Stephen R. Lindemann, Dong-Yup Lee, Jim K. Fredrickson, Hyun-Seob Song

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Modulation of interspecies interactions by the presence of neighbor species is a key ecological factor that governs dynamics and function of microbial communities, yet the development of theoretical frameworks explicit for understanding context-dependent interactions are still nascent. In a recent study, we proposed a novel rule-based inference method termed the Minimal Interspecies Interaction Adjustment (MIIA) that predicts the reorganization of interaction networks in response to the addition of new species such that the modulation in interaction coefficients caused by additional members is minimal. While the theoretical basis of MIIA was established through the previous work by assuming the full availability …


Interrelationships Between Water Use Efficiency And Light Use Efficiency In Four Row Crop Canopies, Meetpal S. Kukal, Suat Irmak Dr. Jan 2020

Interrelationships Between Water Use Efficiency And Light Use Efficiency In Four Row Crop Canopies, Meetpal S. Kukal, Suat Irmak Dr.

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Quantitative evidence of light use efficiency (LUE) controls on water use effi- ciency (WUE) is lacking, especially comparatively across row crops. Field research experiments (2016–2018) were set up for maize (Zea mays L.), soybean [Glycine max (L.) Merr.], sorghum [Sorghum bicolor (L.) Moench], and winter wheat (Triticum aestivum L.), under optimal growth conditions in dry sub-humid conditions. Overall, LUE was able to explain 52% of variance in WUE, and were related as WUE = 1.73 LUE, although crop-specific variation was observed. High- est sensitivity of WUE to changes in LUE was found in sorghum, followed by soybean, winter wheat, and …