Engineering Commons^™

Variable Rate Irrigation Using A Spatial Evapotranspiration Model With Remote Sensing Imagery And Soil Water Content Measurements, Sandeep Bhatti

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

Variable rate irrigation may help in intensification of agriculture by producing more yield per unit inputs. Real time spatial information about water balance components is important for designing VRI prescription maps. This work involved use of a spatial evapotranspiration model for studying spatial variability in an agricultural field at the Eastern Nebraska Research and Extension Center near Mead, Nebraska. Imagery from unmanned aerial systems and Landsat were used as input for the spatial evapotranspiration model. Other inputs into the model were soil water content measurements from neutron probes, weather data, crop data, previous irrigation prescriptions, and soil properties for the …

Soil Health Effects And Stakeholder Perceptions Of Manure And Woody Biomass Application To Cropland In Nebraska, Linda R. Schott

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

Organic products that have historically been viewed as waste products may improve soil health by adding carbon (C) and nutrients to soil. Two such products are woodchips, generated from forest or rangeland management activities, and livestock manure. In Nebraska, eastern redcedar (Juniperus virginiana L.) is a native but invasive tree species inhibiting rangeland productivity. Livestock manure that is underutilized while inorganic fertilizers are imported for crop production presents a water quality risk by contributing to local- and regional-scale nutrient imbalances. Increasing the responsible use of livestock manure in crop fertility programs to improve sustainability of both livestock and crop farms …

Generation Of 360 Degree Point Cloud For Characterization Of Morphological And Chemical Properties Of Maize And Sorghum, Suresh Thapa

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

Recently, imaged-based high-throughput phenotyping methods have gained popularity in plant phenotyping. Imaging projects the 3D space into a 2D grid causing the loss of depth information and thus causes the retrieval of plant morphological traits challenging. In this study, LiDAR was used along with a turntable to generate a 360-degree point cloud of single plants. A LABVIEW program was developed to control and synchronize both the devices. A data processing pipeline was built to recover the digital surface models of the plants. The system was tested with maize and sorghum plants to derive the morphological properties including leaf area, leaf …

Water, Energy, And Carbon Footprints Of Bioethanol From The U.S. And Brazil, Mesfin Mekonnen, Thiago L. Romanelli, Chittaranjan Ray, Arjen Y. Hoekstra, Adam Liska, Christopher M. U. Neale

Adam Liska Papers

Driven by biofuel policies, which aim to reduce greenhouse gas (GHG) emissions and increase domestic energy supply, global production and consumption of bioethanol have doubled between 2007 and 2016, with rapid growth in corn-based bioethanol in the U.S. and sugar cane-based bioethanol in Brazil. Advances in crop yields, energy use efficiency in fertilizer production, biomass-to-ethanol conversion rates, and energy efficiency in ethanol production have improved the energy balance and GHG emission reduction potential of bioethanol. In the current study, the water, energy, and carbon footprints of bioethanol from corn in the U.S. and sugar cane in Brazil were assessed. The …

Developing Serious Games In Engineering Education: Innovation At The Nexus Of Food, Energy, And Water Systems, Nathan Rice

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

At a time when food, energy, and water (FEW) are of the utmost concern to the security and health of the world, an initiative has begun to understand the interactions between these systems. The goal of Innovation at the Nexus of Food, Energy, and Water Systems (INFEWS) is to bring together research fields that typically work in their own silos to solve complex problems increasing the resiliency and sustainability of the FEW system. Stemming from this initiative was a project to produce an educational immersive simulation game to teach youth about how their food is produced, systems thinking, and sustainable …

Invasion Of The P Elements: Tolerance Is Not Futile, Colin D. Meiklejohn, Justin P. Blumenstiel

Biological Systems Engineering: Papers and Publications

Organisms are locked in an eternal struggle with parasitic DNA sequences that live inside their genomes and wreak havoc on their host’s chromosomes as they spread through populations. To combat these parasites, host species have evolved elaborate mechanisms of resistance that suppress their activity. A new study in Drosophila indicates that, prior to the acquisition of resistance, individuals can vary in their ability to tolerate the activity of these genomic parasites, ignoring or repairing the damage they induce. This tolerance results from variation at genes involved in germline development and DNA damage checkpoints and suggests that these highly conserved cellular …

Assessing The Relationship Between Groundwater Nitrate Concentrations And Environmental Variables Through Repeat Sampling And Statistical Machine Learning: Dutch Flats, Nebraska, Martin Wells

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

Nitrate-contaminated aquifers are common in landscapes dominated by agricultural land use. Health concerns related to consuming nitrate-contaminated groundwater are well documented and continued research aimed at decreasing concentrations is critical. A 1990s U.S. Geological Survey (USGS) study focused on groundwater characteristics in the Dutch Flats area of western Nebraska. Agricultural-related practices were determined to largely influence groundwater recharge and nitrate concentrations ([NO₃^-]). Since the conclusion of the USGS study, a transition to more efficient irrigation technology has been observed in this region. The emphasis of this 2016 study was to resample several well nests examined in 1998 …

Cover Crops Have Negligible Impact On Soil Water In Nebraska Maize–Soybean Rotation, J. Burdette Barker, Derek M. Heeren, Katja Koehler-Cole, Charles Shapiro, Humberto Blanco-Canqui, Roger W. Elmore, Christopher A. Proctor, Suat Irmak, Charles A. Francis, Tim M. Shaver, Ali T. Mohammed

Biological Systems Engineering: Papers and Publications

One perceived cost of integrating winter cover cropping in maize (Zea mays L.) and soybean [Glycine max (L.) Merr.] rotation systems is the potential negative impact on soil water storage available for primary crop production. The objective of this 3-year study was to evaluate the effects of winter cover crops on soil water storage and cover crop biomass production following no-till maize and soybean rotations. Locations were near Brule (west-central), Clay Center (south-central), Concord (northeast), and Mead (east-central), Nebraska, United States. Treatments included crop residue only (no cover crop) and a multi-species cover crop mix, both broadcast-seeded before …

Plant Community Composition, Floristic Quality, And Establishment Of Roadside Revegetation In Nebraska, Usa., Jonathan M. Soper

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

Roadside revegetation poses a challenge and opportunity for biodiversity conservation, as the land area occupied by roadsides is not expected to decline in the future. In the context of roadside revegetation activities in rural regions dominated by agricultural land uses, revegetation efforts can establish plant communities that offer unique species that would otherwise be absent on the landscape. To determine the efficacy of roadside revegetation efforts in 1) providing plant communities of high biodiversity value and 2) meeting the expectations of roadside revegetation managers for establishment, we quantified botanical composition, floristic quality, and success in seeding efforts to meet manager …

Comparison Of Nitrogen Fertigation Management Strategies For Center-Pivot Irrigated Maize In The Sub-Humid Area Of China, Jingjing Li, Wenjing Zang, Yaojun Li, Derek M. Heeren, Haijun Yan

Biological Systems Engineering: Papers and Publications

In the sub-humid region of Northeast China, increasing use of center-pivot irrigation systems has caused increased interest in sprinkler fertigation technology in maize production to improve nitrogen (N) use efficiency and protect the environment. However, the lack of fertigation strategies for maize cultivation restrains the adoption of sprinkler fertigation technology. A field experiment was carried out in a sub-humid region of Northeast China on maize to determine the effect of different fertigation management strategies on plant growth, grain yield and nitrate content in the soil during the maize growing season. Three N rates (200, 160, and 120 kg N ha …

An Evaluation Of Unmanned Aerial System Multispectral And Thermal Infrared Data As Information For Agricultural Crop And Irrigation Management, Mitch Maguire

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

Spatial irrigation management has been steadily advancing over the last several years. A current issue with managing irrigation spatially on sub-field scale is the inability to readily collect the spatial field data necessary to properly manage irrigation. Multispectral and thermal infrared imagery used in informing irrigation management decisions was previously collected by satellite and manned aircraft remote sensing platforms. These remote sensing platforms pose issues concerning economic feasibility, revisit intervals, and weather factors that inhibit the collection of data. Recent developments in unmanned aerial systems, which provide an additional means of collecting multispectral and thermal infrared data, have the potential …

Portable Flux Tower Deployments Field Campaign Report, M. S. Torn, L Kuepper, S. C. Biraud, D. P. Billesbach

Biological Systems Engineering: Papers and Publications

Contents

Acronyms and Abbreviations...................................................................... iii

1.0 Summary ....................................................... 1

2.0 Results ........................................... 1

3.0 Publications and References ................................................. 2

4.0 Lessons Learned .................................................................... 2

Tradeoffs In Model Performance And Effort For Long-Term Phosphorus Leaching Based On In Situ Field Data, Ryan P. Freiberger, Derek M. Heeren, Dean E. Eisenhauer, Aaron R. Mittelstet, Guillermo Baigorria

Biological Systems Engineering: Papers and Publications

Phosphorus and N are critical nutrients for agriculture but are also responsible for surface water enrichment that leads to toxic algal growth. Although P loading to surface waters has traditionally been thought to occur primarily in surface runoff, contributions from subsurface transport can also be significant. The primary objectives of this research were to evaluate several methods of representing macropore flow and transport in a finite element model using plot-scale infiltration and leaching data and to compare several models of various levels of complexity to simulate long-term P leaching. To determine flow and transport parameters, single- and dual-porosity models in …

Developing An Integrated Model For The Corn, Ethanol, And Beef Systems Using A Loosely Coupled Web Framework, Ryan Anderson

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

With the global population approaching 9 billion people by the year 2050, the world’s food, energy, and water (FEW) resources must be used more intelligently to provide for everyone. While we understand how individual FEW systems behave using modeling, we cannot understand the full environmental and production impacts of decisions in each system without understanding how they are all linked together. An approach to coupling these systems is starting with identifying a few highly interconnected FEW systems. The corn, ethanol, and beef systems are large economic and agricultural drivers in the Midwest United States and are highly linked. Many individual …

U.S. Agro-Climate In 20th Century: Growing Degree Days, First And Last Frost, Growing Season Length, And Impacts On Crop Yields, Meetpal Singh Kukal, Suat Irmak

Biological Systems Engineering: Papers and Publications

Significant air temperature changes have occurred globally during the 20th century, which are spatially variable to a considerable degree and these changes can have substantial implications in agroecosystem productivity. The agroclimate indicators that are responsible in these contexts are first fall frost (FFF), last spring frost (LSF), climatological growing season (CGS) length, and heat accumulation (growing degree days, GDD). We explore spatial and temporal trends associated with these indices across the continental U.S. (CONUS) during 1900–2014 using datasets collected at 1218 sites. On average, FFF has been occurring later (by 5.4 days century⁻¹), and LSF has been occurring …

Nitrogen And Weed Management In Transplanted Tomato In The Nigerian Forest-Savanna Transition Zone, J. A. Adigun, O. S. Daramola, O. R. Adeyemi, P. M. Olorunmaiye, O. A. Osipitan

Haskell Agricultural Laboratory (Northeast Research and Extension Center)

Weed infestation and inherent low soil fertility are among primary reasons for low yields of tomato in Nigeria. Field trials were carried out during the wet season of 2015 and 2016 to evaluate yield response of tomato to nitrogen (N) application and weed control methods in the forest-savanna transition zone of Abeokuta, Nigeria. Positive relationship exists between growth of weed species and increase in N application. Across the years of study, increase in N up to 90 kg/ha increased weed density by 11–25%, however, the increased N gave the transplanted tomato competitive advantage and thus enhanced weed smothering. Pre-transplant application …

Adam J. Liska: Curriculum Vitae, Adam Liska

Adam Liska Papers

Associate Professor, George Dempster Smith Chair of Industrial Ecology, Departments of Biological Systems Engineering and Agronomy & Horticulture, University of Nebraska-Lincoln 236 L.W. Chase Hall, Lincoln, NE 68583-0726, Ph: (402) 472-8744, e-mail: aliska2@unl.edu

Ph.D. 2003 Biology (magna cum laude), Max Planck Institute of Molecular Cell Biology & Genetics, Technische Universität Dresden, Dresden, Germany

Dynamic Classification Of Moisture Stress Using Canopy And Leaf Temperature Responses To A Step Changes Of Incident Radiation, Erin E. Stevens, George E. Meyer, Ellen T. Paparozzi

Honors Theses

Environmental conditions affect plant productivity and understanding how plants respond to drought stress can be measured in different ways. This study focused on measuring leaf response time to induced water stress. Leaf response time to a step increase and step decrease in radiation was computed for four species of well-watered and water-stressed plants in a controlled environment. The canopy temperature was measured with an infrared thermometer and a thermal imaging camera. Thermal images were analyzed to determine the average temperature of a selected single, unobstructed leaf at the top of the canopy. Both the canopy response time and the single …

Development Of A Sprayer Performance Diagnostic Tool Using Improved Mapping And Error Quantification Practices, Aaron Shearer

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

While sprayer technologies have advanced greatly over the past decade and a half, chemical application errors are still prominent in many in-field operations. Over-application of pesticides can cause harm to the crop, reducing yield, and result in added pollution to the environment. Under-application of pesticides fails to control pests within the field, again lowering crop yields, and causing profit loss for the producer. Current operator feedback from in-field pesticide application operations conveys limited information and often times does not allow the operator to visualize a true representation of their performance. Farm Management Information Systems (FMIS) typically do not account for …

Evaluation Of A Hybrid Reflectance-Based Crop Coefficient And Energy Balance Evapotranspiration Model For Irrigation Management, J. Burdette Barker, Christopher M. U. Neale, Derek M. Heeren, Andrew E. Suyker

Biological Systems Engineering: Papers and Publications

Accurate generation of spatial soil water maps is useful for many types of irrigation management. A hybrid remote sensing evapotranspiration (ET) model combining reflectance-based basal crop coefficients (K_cbrf) and a two-source energy balance (TSEB) model was modified and validated for use in real-time irrigation management. We modeled spatial ET for maize and soybean fields in eastern Nebraska for the 2011-2013 growing seasons. We used Landsat 5, 7, and 8 imagery as remote sensing inputs. In the TSEB, we used the Priestly-Taylor (PT) approximation for canopy latent heat flux, as in the original model formulations. We also used the …

Climate-Driven Crop Yield And Yield Variability And Climate Change Impacts On The U.S. Great Plains Agricultural Production, Meetpal Singh Kukal, Suat Irmak

Biological Systems Engineering: Papers and Publications

Climate variability and trends affect global crop yields and are characterized as highly dependent on location, crop type, and irrigation. U.S. Great Plains, due to its significance in national food production, evident climate variability, and extensive irrigation is an ideal region of investigation for climate impacts on food production. This paper evaluates climate impacts on maize, sorghum, and soybean yields and effect of irrigation for individual counties in this region by employing extensive crop yield and climate datasets from 1968–2013. Variability in crop yields was a quarter of the regional average yields, with a quarter of this variability explained by …

Dynamic Rops Test For Tractors Over 6,000 Kilograms, Caleb M. Lindhorst, Roger M. Hoy, Santosh Pitla, Michael F. Kocher

Biological Systems Engineering: Papers and Publications

OECD static tests (Codes 4, 6, 7, and 8) for agricultural rollover protective structures (ROPS) have become accepted standards for evaluating the ability of these structures to protect the operator during tractor rollover events. The strength properties of some materials typically used in ROPS change because of cold weather embrittlement at low temperatures. The static ROPS tests lack the ability to evaluate the strength of these structures during cold weather. The use of the dynamic ROPS test is well noted as a means for proving cold weather embrittlement resistance properties. Unfortunately, application of the OECD dynamic ROPS test (Code 3) …

Field-Based Scoring Of Soybean Iron Deficiency Chlorosis Using Rgb Imaging And Statistical Learning, Geng Bai, Shawn Jenkins, Wenan Yuan, George L. Graef, Yufeng Ge

Biological Systems Engineering: Papers and Publications

Iron deficiency chlorosis (IDC) is an abiotic stress in soybean that can cause significant biomass and yield reduction. IDC is characterized by stunted growth and yellowing and interveinal chlorosis of early trifoliate leaves. Scoring IDC severity in the field is conventionally done by visual assessment. The goal of this study was to investigate the usefulness of Red Green Blue (RGB) images of soybean plots captured under the field condition for IDC scoring. A total of 64 soybean lines with four replicates were planted in 6 fields over 2 years. Visual scoring (referred to as Field Score, or FS) was conducted …

Unmanned Aerial Systems-Based Remote Sensing For Monitoring Sorghum Growth And Development, Sanaz Shafian, Nithya Rajan, Ronnie Schnell, Muthukumar Bagavathiannan, John Valasek, Yeyin Shi, Jeff Olsenholler

Biological Systems Engineering: Papers and Publications

Unmanned Aerial Vehicles and Systems (UAV or UAS) have become increasingly popular in recent years for agricultural research applications. UAS are capable of acquiring images with high spatial and temporal resolutions that are ideal for applications in agriculture. The objective of this study was to evaluate the performance of a UAS-based remote sensing system for quantification of crop growth parameters of sorghum (Sorghum bicolor L.) including leaf area index (LAI), fractional vegetation cover (f_c) and yield. The study was conducted at the Texas A&M Research Farm near College Station, Texas, United States. A fixed-wing UAS equipped with a …

Internet Of Underground Things In Precision Agriculture: Architecture And Technology Aspects, Mehmet C. Vuran, Abdul Salam, Rigoberto Wong, Suat Irmak

School of Computing: Faculty Publications

The projected increases in World population and need for food have recently motivated adoption of information technology solutions in crop fields within precision agriculture approaches. Internet Of Underground Things (IOUT), which consists of sensors and communication devices, partly or completely buried underground for real-time soil sensing and monitoring, emerge from this need. This new paradigm facilitates seamless integration of underground sensors, machinery, and irrigation systems with the complex social network of growers, agronomists, crop consultants, and advisors. In this paper, state-of-the-art communication architectures are reviewed, and underlying sensing technology and communication mechanisms for IOUT are presented. Moreover, recent advances in …

Three-Dimensional Modeling Of Nitrate-N Transport In Vadose Zone: Roles Of Soil Heterogeneity And Groundwater Flux, Simin Akbariyeh, Shannon L. Bartelt-Hunt, Daniel D. Snow, Xu Li, Zhenghong Tang, Yusong Li

Department of Civil and Environmental Engineering: Faculty Publications

Contamination of groundwater from nitrogen fertilizers in agricultural lands is an important environmental and water quality management issue. It is well recognized that in agriculturally intensive areas, fertilizers and pesticides may leach through the vadose zone and eventually reach groundwater. While numerical models are commonly used to simulate fate and transport of agricultural contaminants, few models have considered a controlled field work to investigate the influence of soil heterogeneity and groundwater flow on nitrate-N distribution in both root zone and deep vadose zone.

In this work, a numerical model was developed to simulate nitrate-N transport and transformation beneath a center …

Impact Of Vegetative Treatment Systems On Multiple Measures Of Antibiotic Resistance In Agricultural Wastewater, Lisa M. Durso, Daniel N. Miller, Christopher G. Henry

Biological Systems Engineering: Papers and Publications

Wastewater is an important vector of antibiotic resistant bacteria and antibiotic resistance genes (ARB/G). While there is broad agreement that ARB/G from agricultural (ag) wastewaters can be transported through the environment and may contribute to untreatable infectious disease in humans and animals, there remain large knowledge gaps surrounding applied details on the types and amounts of ARB/G associated with different agricultural wastewater treatment options and different ag production systems. This study evaluates a vegetative treatment system (VTS) built to treat the wastewater from a beef cattle feedlot. Samples were collected for three years, and plated on multiple media types to …

2018 Nebraska Groundwater Quality Monitoring Report

Nebraska Department of Environmental Quality: Reports

The 2001 Nebraska Legislature passed LB329 (Neb. Rev. Stat. §46-1304) which, in part, directed the Nebraska Department of Environmental Quality (NDEQ) to report on groundwater quality monitoring in Nebraska. Reports have been issued annually since December 2001. The text of the statute applicable to this report follows: “The Department of Environmental Quality shall prepare a report outlining the extent of ground water quality monitoring conducted by natural resources districts during the preceding calendar year. The department shall analyze the data collected for the purpose of determining whether or not ground water quality is degrading or improving and shall present the …

Special Issue: Microbial Community Modeling: Prediction Of Microbial Interactions And Community Dynamics, Hyun-Seob Song

Biological Systems Engineering: Papers and Publications

Microbial communities are networks of species, the interaction structure of which dynamically reorganizes in a varying environment. Even in a static condition, community dynamics are often difficult to predict due to highly nonlinear interspecies interactions. Understanding the fundamental principles of microbial interactions is therefore key for predicting and harnessing community function and properties. As extensively reviewed previously, mathematical models and computational methods that can predictively link interactions to community behaviors are indispensable tools for achieving this goal [1].

Evaluation Of Variable Rate Irrigation Using A Remote-Sensing-Based Model, John Burdette Barker, Derek M. Heeren, Christopher M.U. Neale, Daran Rudnick

Biological Systems Engineering: Papers and Publications

Improvements in soil water balance modeling can be beneficial for optimizing irrigation management to account for spatial variability in soil properties and evapotranspiration (ET). A remote-sensing-based ET and water balance model was tested for irrigation management in an experiment at two University of Nebraska-Lincoln research sites located near Mead and Brule, Nebraska. Both fields included a center pivot equipped with variable rate irrigation (VRI). The study included maize in 2015 and 2016 and soybean in 2016 at Mead, and maize in 2016 at Brule, for a total of 210 plot-years. Four irrigation treatments were applied at Mead, including: VRI based …