Bioresource and Agricultural Engineering Commons^™

An Investigation Of Surface Water Sediment Source Tracking Using Bacterial Metagenomics And Elemental Fingerprinting, Yanchong Huangfu

Doctoral Dissertations

Excess suspended sediment in river systems commonly degrades surface water quality. A sediment source tracking approach is necessary to target management practices that will reduce significant sources of sediment in rainfall runoff and restore water quality. Sediment source tracking utilizes the biogeochemical characteristics of sediment, often paired with a mathematical model, to link eroding source materials and in-stream suspended sediment. However, there are still many questions left unanswered in using this approach, including simultaneously identifying fecal contamination sources, quantifying the reliability of sediment tracers, and methods to assess the accuracy of sediment source identification. The research herein utilized the microbial …

Comparative Analysis Of Mosquito Trap Counts In The Peruvian Amazon: Effect Of Trap Type And Other Covariates On Counts And Diversity, George W. Peck, Fanny Castro-Llanos, Victor Lopez-Sifuentes, Erica Lindroth

Civil and Environmental Engineering Faculty Publications and Presentations

Efficient detection of multiple species of adult mosquitoes in various habitats using effective traps is a crucial 1st step in any disease prevention program. Novel trap types that target tropical vectors of human diseases require field testing in the habitat of the vector–disease system in question. This paper analyzes a series of mosquito trapping studies conducted at Mapacocha, San Juan Bautista District, Loreto, Peru, during August–September 2013 and April–May 2014. Six trap configurations were evaluated in forest and rural locations. Adult mosquito counts were analyzed using full Bayesian inference of multilevel generalized linear models and posterior probability point estimates of …

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

Department of 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 …

Causal Loop Development Activity, Ali Mirchi

All ECSTATIC Materials

Students will work in groups to develop a causal loop diagram (CLD) to illustrate the structure and expected behavior of the fictional water short state of Nevizonato facilitate qualitative discussion of expected outcomes of a proposed water management strategy. This activity requires familiarity with systems thinking and system dynamics modeling. CLDs are introduced as a fundamental systems thinking tool for conceptual modeling.

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

Department of 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 …

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

Department of 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 …

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

Department of 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

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

Department of 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 …

Development Of A Digital Rain-Sensing Irrigation Pump Controller And An Android Enabled Bluetooth Paddlewheel Flowmeter, Jayendra Mishra

Graduate Theses and Dissertations

For better irrigation efficiency, it is recommended that farmers track their water consumption to avoid over-irrigating. However, it is difficult to implement this as it is labor intensive to supervise pumps manually and available technologies require high investment. Therefore, a rain sensing pump controller for 3-phase electric irrigation pumps and a stand-alone portable Android enabled paddlewheel flowmeter has been developed to test their feasibility.

The pump timer is a retrofit device for irrigation pump panels. The controller allows an irrigator to start and stop the pump with less supervision. An infrared rain sensor is integrated with the controller to measure …

Investigating Initial Interactions Between Silver Nanoparticles And Wastewater, Casey Gibson

Biological and Agricultural Engineering Undergraduate Honors Theses

The use of nanoparticles (NPs) has increased exponentially in the last 15-20 years, especially in the consumer market. NPs are currently found in over 1800 commercial products, including cosmetics, clothing, packaging, and toys. As a result, NPs can enter the environment via wastewater (WW) streams, leading to new challenges in WW treatment. This study focuses on the initial fate of silver nanoparticles (AgNPs) in WW. The AgNP interaction including aggregation and dissolution in both synthetic and real WW were studied. Real WW was collected from the primary-clarifier, secondary-clarifier, and effluent WW streams at two local WW treatment plants (Westside and …

Assessing Auto-Flocculation Of Microalgae In Wastewater Treatment, Alexander Parr

Biological and Agricultural Engineering Undergraduate Honors Theses

Biofuels produced from algae have the prospect to provide a cheap, carbon neutral alternative to fossil fuels. However, the high cost for harvesting algae limits its wide application, as the preferred algae strains for biofuel production are typically unicellular microalgae that do not settle in water very well. Recently, researchers have been focusing on developing a biological method to achieve the sedimentation of algae through flocculation. A recent study has concluded that introducing microalgae that self-flocculates increases the recovery of the desired microalgae, similar to the effect of using coagulant to flocculate the algae. This option can potentially be more …

Chloride Salt Inhibition On Lipid Production In Wastewater-Grown Algae For Biofuel Production, Will Richardson

Biological and Agricultural Engineering Undergraduate Honors Theses

Algae are increasingly being recognized as useful organisms for many applications in today’s world. Their ability to remove nitrogen, phosphorus, and trace metals from water while adding oxygen to water makes them an attractive tertiary treatment technology in municipal wastewater treatment facilities. At the same time, algae produce lipids and carbohydrates that are useful for biofuel production, and they are not a human food crop unlike many biofuel feedstocks. In this study the effect of increased chloride concentrations in wastewater was assessed on the ability of two species of algae, Chlorella vulgaris and Scenedesmus dimorphus, to function as a …

Biobutanol Production From Cellulosic And Sugar-Based Feedstock From The Corn Plant, Reyna Gomez-Flores

Electronic Thesis and Dissertation Repository

In this thesis, biobutanol production by biological fermentation was investigated from the corn plant, integrating two approaches. The first one was to utilize corn cobs, a cellulosic-based material. The second, using a new sugar-based material, sugarcorn juice. Utilizing suitable Clostridia strains for each substrate, these approaches converged into a biorefinery concept to produce renewable biofuels in Ontario, Canada. The corn cob pretreatment was carried out by a dilute acid method resulting in temperature as the variable with most significant effect towards glucose liberation. The enzymatic hydrolysis was performed utilizing a very low concentration of an enzymatic stock solution with approximately …

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

Department of 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

Department of 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 …

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 …

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 …

Evaluating E. Coli Particle Attachment And The Impact On Transport During High Flows, Louis Amegbletor

Electronic Theses and Dissertations

Fecal indicator bacteria, including E. coli, are the leading cause of water quality impairments within assessed waters in the United States. The source of E. coli includes WWTP, leaking sewers, animal manure, wildlife, livestock, and stream bed sediment. Storm events contribute to bacteria loading within waters through wash-in of land sources of bacteria and resuspension of bacteria within sediments. Bacteria introduced into the water column are either attached to particles or are unattached (or free-living). The goal of this study was to examine the attachment of E. coli to different particle sizes, including their impact on contributing to water …

Impacts Of Cover Crops On Soil Physical Properties: Field Capacity, Permanent Wilting Point, Soil-Water Holding Capacity, Bulk Density, Hydraulic Conductivity, And Infiltration, Suat Irmak, Vivek Sharma, Ali T. Mohammed, Koffi Djaman

Department of Biological Systems Engineering: Papers and Publications

Field experiments were carried out to quantify the effects of cover cropping on soil physical properties. Field capacity (FC), permanent wilting point (PWP), soil-water holding capacity (SWHC), bulk density (  b), saturated and unsaturated hydraulic conductivity (Ks and Kus, respectively), and infiltration rates were measured and compared for four land cover treatments [cover crop without seed maize (CC), seed maize followed by cover crop (SCCC), bare soil, and seed maize without cover crop (SC)] in three large-scale production fields (~64 ha each) with silt loam soil in the 2012-2013, 2013-2014, 2014-2015, and 2015-2016 cover crop growing seasons. All production …

Detection Of Multi-Tomato Leaf Diseases (Late Blight, Target And Bacterial Spots) In Different Stages By Using A Spectral-Based Sensor, Jinzhu Lu, Reza Ehsani, Yeyin Shi, Ana Isabel De Castro, Shuang Wang

Department of Biological Systems Engineering: Papers and Publications

Several diseases have threatened tomato production in Florida, resulting in large losses, especially in fresh markets. In this study, a high-resolution portable spectral sensor was used to investigate the feasibility of detecting multi-diseased tomato leaves in different stages, including early or asymptomatic stages. One healthy leaf and three diseased tomato leaves (late blight, target and bacterial spots) were defined into four stages (healthy, asymptomatic, early stage and late stage) and collected from a field. Fifty-seven spectral vegetation indices (SVIs) were calculated in accordance with methods published in previous studies and established in this study. Principal component analysis was …

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

Department of 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 …

Effects Of Subsurface Drainage Systems On Water And Nitrogen Footprints Simulated With Rzwqm2, Kristina J. Craft, Matthew J. Helmers, Robert W. Malone, Carl H. Pederson, Linda R. Schott

Department of Biological Systems Engineering: Papers and Publications

Developing drainage water management (DWM) systems in the Midwest to reduce nitrogen (N) transport to the northern Gulf of Mexico hypoxic zone requires understanding of the long-term performance of these systems. Few studies have evaluated long-term impacts of DWM, and the simulation of controlled drainage (CD) with the Root Zone Water Quality Model (RZWQM) is limited, while shallow drainage (SD) has not been examined. We tested RZWQM using nine years (2007-2015) of field data from southeast Iowa for CD, SD, conventional drainage (DD), and undrained (ND) systems and simulated the long-term (1971-2015) impacts. RZWQM accurately simulated N loss in subsurface …

The Open Source Gaitor Suite For Rodent Gait Analysis, Brittany Y. Jacobs, Emily H. Lakes, Alex J. Reiter, Spencer P. Lake, Trevor R. Ham, Nic D. Leipzig, Stacy L. Porvasnik, Christine E. Schmidt, Rebecca A. Wachs, Kyle D. Allen

Department of Biological Systems Engineering: Papers and Publications

Locomotive changes are often associated with disease or injury, and these changes can be quantified through gait analysis. Gait analysis has been applied to preclinical studies, providing quantitative behavioural assessment with a reasonable clinical analogue. However, available gait analysis technology for small animals is somewhat limited. Furthermore, technological and analytical challenges can limit the effectiveness of preclinical gait analysis. The Gait Analysis Instrumentation and Technology Optimized for Rodents (GAITOR) Suite is designed to increase the accessibility of preclinical gait analysis to researchers, facilitating hardware and software customization for broad applications. Here, the GAITOR Suite’s utility is demonstrated in 4 models: …

Greenhouse Gas Emissions From Beef Feedlot Surface Materials As Affected By Diet, Moisture, Temperature, And Time, Bryan L. Woodbury, John E. Gilley, David B. Parker, Bobbi S. Stomer

Department of Biological Systems Engineering: Papers and Publications

A laboratory study was conducted to measure the effects of diet, moisture, temperature, and time on greenhouse gas (GHG) emissions from feedlot surface materials (FSM). The FSM were collected from open-lot pens where beef cattle were fed either a dry-rolled corn (DRC) diet containing no wet distillers grains with solubles (WDGS) or a DRC diet containing 35% WDGS. The FSM were collected, air-dried or mixed with 3.0 L of water to represent dry or wet conditions, and then incubated at temperatures of 5°C, 15°C, 25°C, or 35°C. Static flux chambers were used to quantify GHG emissions over a 14-day period. …

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

Department of 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 …

Surface Detention On Cropland, Rangeland, And Conservation Reserve Program Areas, John E. Gilley

Department of Biological Systems Engineering: Papers and Publications

One of the factors contributing to overland flow on upland areas is water stored temporarily in a thin sheet on the soil surface as surface detention. This study was conducted to quantify surface detention on selected cropland, rangeland, and Conservation Reserve Program (CRP) sites. Surface detention was determined from the recession portion of runoff hydrographs corresponding with the period when rainfall had ceased but runoff continued. The hydrographs were generated from six previously reported rainfall simulation studies conducted on paired 3.7 m wide  10.7 m long plots on which approximately 128 mm of rainfall was applied. Surface detention values …

Evaluation Of The Accuracy Of Machine Reported Can Data For Engine Torque And Speed (J1939), Rodney A. Rohrer, Joe D. Luck, Santosh K. Pitla, Roger M. Hoy

Department of Biological Systems Engineering: Papers and Publications

Most modern off-road machinery use embedded electronic controllers connected to a controller area network (CAN) to broadcast machine information for on-board processes and diagnostics. Commercially available tools can record CAN data for a variety of research and commercial uses. For agricultural tractors, there is an opportunity to create advanced test procedures that are more representative of field operations and that could supplement existing machine performance tests, such as the OECD Code 2 Standard Code for the Official Testing of Agricultural and Forestry Tractor Performance. CAN parameters provide an efficient way to collect tractor performance data during field operations. However, the …

Prediction Of Agricultural Implement Hydraulic Power Requirements Using Controller Area Network Bus Data, Gabriel P. Stoll, Rodney A. Rohrer, Santosh K. Pitla, Joe D. Luck

Department of Biological Systems Engineering: Papers and Publications

One of the important challenges in agricultural machinery research is the ability to effectively determine power requirements of a given field operation. The Controller Area Network (CAN) Bus, also known as ISOBUS, has proven to be an effective digital tool for tractor and implement data collection. This study attempted to determine implement hydraulic power requirements using a combination of existing public tractor CAN messages and minimal added sensors. The sensor signals were published on the CAN bus for ease of simultaneous sensor signal and CAN message data collection. Based upon the available CAN messages, this study attempted to measure hydraulic …

Effects Of Alternate Wetting And Drying Irrigation Regime And Nitrogen Fertilizer On Yield And Nitrogen Use Efficiency Of Irrigated Rice In The Sahel, Koffi Djaman, Valere C. Mel, Lamine Diop, Abdoulaye Sow, Raafat El-Namaky, Baboucarr Manneh, Kazuki Saito, Koichi Futakuchi, Suat Irmak

Department of Biological Systems Engineering: Papers and Publications

The objectives of this study were to investigate water saving strategies in the paddy field and to evaluate the performance of some of the newly released rice varieties. Field experiments were conducted at Fanaye in the Senegal River Valley during two rice growing seasons in 2015. Three irrigation regimes ((i) continuous flooding, (ii) trigging irrigation at soil matric potential (SMP) of 30 kPa, (iii) trigging irrigation at SMP of 60 kPa) were tested in an irrigated lowland rice field. Irrigation regimes (ii) and (iii) are alternate wetting and drying (AWD) cycles. Four inbred rice varieties (NERICA S-21, NERICA S-44, Sahel …