Engineering Commons^™

"Apps"—An Innovative Way To Share Extension Knowledge, Joseph S. Dvorak, Tanya C. Franke-Dvorak, Randy R. Price

Biosystems and Agricultural Engineering Faculty Publications

Extension professionals across the country are continuously seeking innovative ways to reach clientele and to disseminate timely, educational information. A new avenue to reach clientele includes the use of smartphone "apps." The "Machinery Sizing" app, which was developed to ease the estimation of tractor horsepower to implement sizing for Extension clientele anytime, anywhere, is explained as a key example for Extension professionals to utilize apps in disseminating information to clientele. There are many benefits to using apps, including information availability wherever Internet service is available on the smartphone, ease of computations of equations, and automatic updates being sent to users.

Long-Term Trends In Air Temperature Distribution And Extremes, Growing Degree-Days, And Spring And Fall Frosts For Climate Impact Assessments On Agricultural Practices In Nebraska, Kari E. Skaggs, Suat Irmak

Biological Systems Engineering: Papers and Publications

Air temperature influences agricultural practices and production outcomes, making detailed quantifications of temperature changes necessary for potential positive and negative effects on agricultural management practices to be exploited or mitigated. Temperature trends of long-term data for five agricultural locations, ranging from the subhumid eastern to the semiarid western parts of Nebraska, were studied to determine local temperature changes and their potential effects on agricultural practices. The study quantified trends in annual and monthly average maximum and minimum air temperature (T_max and T_min), daily temperature range (DTR), total growing degree-days, extreme temperatures, growing-season dates and lengths, and …

Developing A Restorable Wetland Index For Rainwater Basin Wetlands In South-Central Nebraska: A Multi-Criteria Spatial Analysis, Zhenghong Tang, Xu Li, Nan Zhao, Ruopu Li, F. Edwin Harvey

Community and Regional Planning Program: Faculty Scholarly and Creative Activity

It is always challenging for decision makers to prioritize wetland conservation programs at the landscape scale. This study employed a GIS-based multi-criteria spatial decision support tool that identified locations with the highest restoration potential for wetland conservation programs in the Rainwater Basin in south-central Nebraska. Five indicators were considered to assess wetland restoration potential: (1) Vegetation characteristics; (2) Soil characteristics; (3) Water volume released from hydrological modification of agricultural irrigation pits; (4) Topographical depression status; and (5) Habitat condition. The results suggested 192 (1.6% of the total) hydric soil footprints as the highest prioritized locations for future wetland restoration programs. …

Initial Changes In Species Cover Following Savanna Restoration Treatments In Western Iowa, David A. Mckenzie, Thomas B. Bragg, David M. Sutherland

Great Plains Research: A Journal of Natural and Social Sciences

Study areas in the Iowa Loess Hills were used to evaluate short-term responses of understory species to three treatment methods designed to facilitate restoration of Quercus macrocarpa savanna. Treatments included burning alone, burning with thinning, and burning with clear-cutting. Plant abundance and diversity were compared before treatment and one year after treatment. Ninety-nine plant species were identified during the study, of which 40 were new following treatment, although most of these were forest associates. Increases in diversity of understory species were observed after treatment, particularly in plots with combined burning and thinning. The forb group was most consistent in response …

Characterizing Physical Properties Of Gas-Phase Biofilter Media, Guilherme Del Nero Maia, G. Tatiana Sales, George B. Day V, Richard S. Gates, Joseph L. Taraba

Biosystems and Agricultural Engineering Faculty Publications

Gas-phase biofiltration is an effective technology for reduction of odors and trace-gas contaminants. Significant contributions to the technical literature regarding the characterization of biofilter media have been generated in the past two decades. Nevertheless, the information produced has not been systematically organized. The objective of this study is to demonstrate and document methods for physical characterization of gas-phase compost biofilters (GPCB). The inclusion of moisture content, compaction, and particle size effects in the determination of media bulk density and porosity, field capacity, drying rate analysis, water sorption isotherms, and resistance to airflow is demonstrated. Results indicated that: (1) higher moisture …

Sbx7 Flow Rate Measurement Compliance For Agricultural Irrigation Districts, Charles M. Burt, Evan Geer

BioResource and Agricultural Engineering

Senate Bill x7-7 (SBx7-7) requires documented volumetric accounting to individual turnouts for water deliveries. Section 597.3 of the bill lists two very different requirements for devices. This document examines the requirements of SBx7 and the implications for agricultural irrigation districts. The definitions and impacts of flow rate and volumetric accuracy are defined. Example scenarios and solutions are offered, as well as descriptions of applicable devices.

Effects Of Sprinkler, Partial Sprinkler/Drip, And Drip Only Irrigation On Strawberry Transplants 2011-2012, Stuart Styles

BioResource and Agricultural Engineering

The Cal Poly Irrigation Training and Research Center (ITRC), in collaboration with academic, water district, and industry partners, proposes to evaluate new strategies for drip irrigation on strawberries to minimize runoff during transplant establishment.

The most common method used for irrigating strawberries is a mix of sprinkler irrigation and drip. Growers use sprinkler irrigation for bed preparation and salinity control, then eventually switch to drip irrigation after transplanting, but continue to use sprinkler irrigation as an insurance policy (for bonding between plant roots and soil bonding, washing off the leaves, controlling salinity, and frost). However, field observations have shown that …

Hydrologic Evaluation Of Established Rain Gardens In Lincoln, Nebraska, Andrew R. Anderson, Thomas G. Franti, David P. Shelton

Biological Systems Engineering: Papers and Publications

Increased urbanization has resulted in water quality and flooding problems for many receiving waters in the United States. Rain gardens are one type of best management practice commonly used in low impact development (LID). Many studies have evaluated large engineered bioretention cells in research settings. There is little information on the effectiveness of homeowner-maintained rain gardens that rely on deep percolation as the method for water exfiltration. Repeatable controlled experiments are very rare in hydrologic studies due to the inherent variability of weather data. The objective of this study was to evaluate the hydrologic properties of twelve established rain gardens …

Dynamics Of Depression Storage During Sprinkler Irrigation And Precipitation Events, Michael B. Mckinney

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

Surface depression storage (D_s) is the volume of precipitation excess which is stored by surface microrelief features of soils. The volume of water stored in surface depressions when precipitation rate exceeds infiltration rate reduces the amount of runoff generated. Because Ds is dependent on soil microrelief, land slope, and crop residue, tillage and management practices can have a considerable impact on the magnitude of this value.

When modeling irrigation systems and surface hydrology, depression storage is often treated as a static abstraction, meaning that maximum storage volume must be filled before runoff occurs. However, several researchers have documented …

Implementation Of Magnetic Meters For Irrigation Volumetric Measurement, Stuart Styles, Lynn Groundwater

BioResource and Agricultural Engineering

The irrigation industry is experiencing a growth in the use of magnetic meters for measuring the flow rate and volume in irrigation pipelines. Historically, propeller meters have been the device selected by users. New legislation in California (SB7x7) will require measurement devices at key locations for irrigation water delivery. Some users are very interested in the magnetic meter for making the measurement at the turnout or farm gate. The key feature of the new meter is the ability for the device to work in less than ideal flow conditions. Electromagnetic meters have been tested by the Irrigation Training and Research …

Life Cycle Boundaries And Greenhouse Gas Emissions From Beef Cattle, Quentin M. Dudley

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

Beef cattle are estimated to directly contribute 26% of U.S. agricultural greenhouse gas (GHG) emissions, and future climate change policy may target reducing these emissions. Life cycle assessment (LCA) of GHG emissions from U.S. feedlot beef cattle was conducted to compare methods of the U.S. Environmental Protection Agency (EPA) with a more complete evaluation of emissions. The inclusion of emissions from crop production for feed, associated land use change, and other minor factors nearly doubled GHG emissions associated with beef feedlots from the EPA Annual Inventory estimate of 1611 kgCO₂e hd^-1 yr^-1 to 3182 ± 167 …

Observations Of Localised Effects Of The Busselton Compensating Basins On Surface Water, Groundwater And Soil Salinity, D L. Bennett, Richard J. George Dr

Resource management technical reports

Between 2001 and 2009 the Water Corporation constructed three flood-compensating basins on farmland in the Vasse and Sabina river catchments, upstream of in the city of Busselton. The basins are designed to reduce the risk of flooding in urban areas of Busselton by temporarily storing and then regulating runoff during flood events. This report fulfils the reporting requirements of a contract between the Water Corporation and the Department of Agriculture and Food. Data relating to the local groundwater and surface-water dynamics, salinity, nutrients and pH, plus changes to shallow and deep-soil salinity (from repeat ground-based electromagnetic induction [EM] surveying), was …

Bivariate Drought Analysis Using Entropy Theory, Zengchao Hao, Vijay P. Singh

2011 Symposium on Data-Driven Approaches to Droughts

Drought duration and severity are two properties that are usually needed for drought analysis. To characterize the correlation between the two drought properties, a bivariate distribution is needed. A new method based on entropy theory is proposed for constructing the bivariate distribution that is capable of modeling drought duration and severity with different marginal distributions. Parameters of the joint distribution are estimated with Newton’s method. Monthly streamflow data from Brazos River at Waco, Texas, are employed to illustrate the application of the proposed method to model drought duration and severity for drought analysis.

Wine Grape Irrigation Management, Charles M. Burt

BioResource and Agricultural Engineering

This report addresses difficulties in calculating correct ET values for wine grapes, and includes tips for wine grape irrigation scheduling, regulated deficit irrigation, and soil moisture measurement, and crop canopy cover estimates.

Mapping Spatially Interpolated Precipitation, Reference Evapotranspiration, Actual Crop Evapotranspiration, And Net Irrigation Requirements In Nebraska: Part I. Precipitation And Reference Evapotranspiration, Vivek Sharma, Suat Irmak

Biological Systems Engineering: Papers and Publications

Precipitation and reference evapotranspiration are two important variables in hydrologic analyses, agricultural crop production, determining actual crop evapotranspiration and irrigation water requirements, and irrigation management. Both variables vary in space and time, and the weather networks that measure or quantify and report both variables are too sparse for practical applications by water resources planners, managers, and irrigators. Long-term (1986- 2009) average annual (January to December), seasonal (growing season, May to September), and monthly (May, June, July, August, and September) precipitation and Penman-Monteith-estimated alfalfa-reference evapotranspiration (ET_ref) were spatially interpolated and mapped for all 93 counties in Nebraska using the …

Nutrient Losses In Runoff From Feedlot Surfaces As Affected By Unconsolidated Surface Materials, John E. Gilley, Jason R. Vogel, Roger A. Eigenberg, David B. Marx, Brian L. Woodbury

Biological Systems Engineering: Papers and Publications

Beef cattle feedlots contain unconsolidated surface materials (loose manure pack) that accumulate during a feeding cycle. The effects of varying amounts of unconsolidated surface materials on runoff nutrient losses are not well understood. The objectives of this study were to (1) compare runoff nutrient losses from feedlot surfaces containing varying amounts of unconsolidated surface materials, (2) determine if differences in runoff nutrient losses exist among rainfall simulation runs, (3) relate runoff nutrient losses to selected feedlot soil characteristics, and (4) identify the effects of varying runoff rate on nutrient loss rates from feedlot surfaces. This study was conducted on 0.75 …

The Use Of High-Solids Loadings In Biomass Pretreatment – A Review, Alicia A. Modenbach, Sue E. Nokes

Biosystems and Agricultural Engineering Faculty Publications

The use of high‐solids loadings (≥ 15% solids, w/w) in the unit operations of lignocellulose conversion processes potentially offers many advantages over lower‐solids loadings, including increased sugar and ethanol concentrations and decreased production and capital costs. Since the term lignocellulosic materials refers to a wide range of feedstocks (agricultural and forestry residues, distillery by‐products, and dedicated energy crops like grasses), the term “solids loading” here is defined by the amount of dry material that enters the process divided by the total mass of material and water added to the material. The goal of this study is to provide a consolidated …

Effects Of Manure Handling And Application Method On Odor And Gas Emission Potential Of Swine Manure, Rick R. Stowell

Biological Systems Engineering: Papers and Publications

Manure composition and emissions potential of swine manure were investigated in opposing contexts of desired and undesired methane generation. In the main study, the full-scale treatment effects of anaerobic digestion on the air emissions potential of swine manure were investigated. Manure slurry and digester effluent samples were collected from a pork production facility in eastern Nebraska that utilizes a complete-mix anaerobic digester to treat the manure and produce biogas for use in generating electricity. Samples were collected from three sites in the manure stream (below-barn pit, digester outlet, and holding pond) from 9/22/08 through 12/2/09 in order to observe changes …

Evaluation Of The Bank Stability And Toe Erosion Model (Bstem) For Predicting Lateral Retreat On Composite Streambanks, Taber L. Midgley, Garey A. Fox, Derek M. Heeren

Biological Systems Engineering: Papers and Publications

Streambank erosion is known to be a major source of sediment in streams and rivers. The Bank Stability and Toe Erosion Model (BSTEM) was developed in order to predict streambank retreat due to both fluvial erosion and geotechnical failure. However, few, if any, model evaluations using long-term streambank retreat data have been performed. The objectives of this research were to (1) monitor long-term composite streambank retreat during a hydraulically active period on a rapidly migrating stream, (2) evaluate BSTEM’s ability to predict the measured streambank retreat, and (3) assess the importance of accurate geotechnical, fluvial erosion, and near-bank pore-water pressure …

Chemical Modification Of Polysaccharides Using Reactive Extrusion, Pratik Bhandari

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

The objective of this dissertation was to study the use of reactive extrusion for the chemical modifications of starch and cellulose. A carboxymethyl derivative of starch and carboxymethyl and acetate derivatives of cellulose were prepared using reactive extrusion.

Carboxymethyl starch with rapid swelling properties in water was prepared using reactive extrusion. This was achieved by controlling the gelatinization and through the use of NaOH by controlling the water/ethanol ratio. The effects of NaOH, H₂O, temperature, ethanol, sodium mono chloro acetate, sodium tripolyphosphate, citric acid, epichlorohydrin and extruder screw configuration on the degree of substitution of carboxymethyl starch were …

Wheat Strip Effects On Nutrient Loads Following Variable Manure Applications, Chance Thayer, John E. Gilley, Lisa M. Durso, David B. Marx

Biological Systems Engineering: Papers and Publications

Vegetative filters have been found to significantly reduce nutrient loads in runoff. This study was conducted to: (1) evaluate the effects of a narrow wheat strip, varying manure application rates, and different overland flow rates on runoff nutrient loads following application of beef cattle manure; (2) determine the upper capacity of a narrow wheat strip to reduce nutrient loads by applying excessive amounts of manure; and (3) compare the effectiveness of narrow wheat strips and grass hedges in reducing runoff nutrient loads. A 1.4 m wide strip of actively growing winter wheat was located at the bottom of selected 0.75 …

Identification And Characterization Of Mtoa: A Decaheme C-Type Cytochrome Of The Neutrophilic Fe(Ii)-Oxidizing Bacterium Sideroxydans Lithotrophicus Es-1, Juan Liu, Zheming Wang, Sara M. Belchik, Marcus J. Edwards, Chongxuan Liu, David W. Kennedy, Eric D. Merkley, Mary S. Lipton, Julea N. Butt, David J. Richardson, John M. Zachara, James K. Fredrickson, Kevin M. Rosso, Liang Shi

US Department of Energy Publications

The Gram-negative bacterium Sideroxydans lithotrophicus ES-1(ES-1) grows on FeCO₃ or FeS at oxic–anoxic interfaces at circumneutral pH, and the ES-1-mediated Fe(II) oxidation occurs extracellularly. However, the molecular mechanisms underlying ES-1’s ability to oxidize Fe(II) remain unknown. Survey of the ES-1 genome for candidate genes formicrobial extracellular Fe(II) oxidation revealed that it contained a three-genecluster encoding homologs of Shewanella oneidensis MR-1(MR-1) MtrA, MtrB, and CymA that are involved in extracellular Fe(III) reduction. Homologs of MtrA and MtrB were also previously shown to be involved in extracellular Fe(II) oxidation by Rhodopseudomonas palustris TIE-1. To distinguish them from those found in MR-1, …

Basin-Wide Remote Sensing Of Actual Evapotranspiration And Its Influence On Regional Water Resources Planning, Daniel J. Howes, Charles M. Burt, Kyle Feist

BioResource and Agricultural Engineering

The Irrigation Training & Research Center (ITRC) at Cal Poly State University, San Luis Obispo has been using METRIC to compute actual evapotranspiration from remote sensing sources (namely LandSAT images). The driving force behind this is the increasing need for improved evapotranspiration information on a large scale. A recent study in the Mexicali Valley of Baja California, Mexico utilized the ITRC-modified METRIC procedure to compute the crop and riparian evapotranspiration component of a basin-wide water balance. The resulting comparison between the mass balance computed change in groundwater storage and that computed using groundwater elevation data showed excellent agreement. For water …

Pump Performance With Sand Wear, Charles M. Burt, Kyle Fesit

BioResource and Agricultural Engineering

In many installations, pump performance declines over time due to sand wear. In order to pinpoint the type and rate of wear caused by pumping water with higher-than-average sand concentrations and its direct effect on various pump impeller materials, vertical pump impeller/bowl assemblies of approximately 900 GPM were each pumped for up to 2500 hours with high concentrations of sand in the water. Two different impeller materials were used for a total of five configurations. Well pump operation was simulated by maintaining a constant discharge pressure. The degrading performance, in terms of changing flow rate and kilowatt load, was recorded …

Spatial Variability In Evapotranspiration Related To Irrigation System Distribution Uniformity, Daniel J. Howes, Lucas Hoffmann, Franklin Gaudi

BioResource and Agricultural Engineering

Understanding the causes of variable ET in a field is critical for maximizing yield on a per-acre basis as well as for proper irrigation scheduling and regional water management. Since 2004, the ITRC has provided technical irrigation support and management for over 2,000 acres of center pivot irrigated forage crops being supplied by reclaimed water near Palmdale, California. Irrigation scheduling is conducted using a daily soil water balance dual crop coefficient approach. Detailed records on planting and harvest dates, daily water applications, pivot run speeds, and annual distribution uniformity evaluations are maintained along with daily reference evapotranspiration data from a …

Comparison Of Field Level And Regional Actual Etc Values Developed From Remote Sensing And Dual Crop Coefficient Procedure, Daniel J. Howes, Lucas Hoffmann, Franklin Gaudi

BioResource and Agricultural Engineering

Crop evapotranspiration (ETc) estimates are important for regional water planning as well as irrigation scheduling. Traditional ETc computations utilize published crop coefficients (basal) that are adjusted on a daily basis depending on soil water availability (i.e., dual crop coefficient method). Recent advancements include using remote sensing data such as LandSAT combined with a surface energy balance algorithm (METRIC), allowing crop evapotranspiration to be computed for each pixel throughout images taken during the season. There are limitations and advantages for both methods. Comparisons of soil water balance evapotranspiration values to METRIC values for two scenarios in different regions of California have …

Development And Deployment Of A Bioreactor For The Removal Of Sulfate And Manganese From Circumneutral Coal Mine Drainage, C. B. Mastin, J. D. Edwards, Christopher D. Barton, Anastasios D. Karathanasis, Carmen T. Agouridis, Richard C. Warner

Forestry and Natural Resources Faculty Publications

Surface mining, in the form of contour mining and mountain-top removal, is a common means for retrieving coal in the Appalachian Coal Belt region of Kentucky. Overburden or excess spoil generated by these two methods is placed in valley fills. Traditionally Constructed fills have been shown to adversely impact headwater ecosystems via stream burial and through alterations to the hydrology, sediment supply, water quality and biological composition of downstream reaches. Mine drainages emanating from the toe of valley fills often contain elevated levels of total dissolved solids and heavy metals. Drainage chemistry from Guy Cove, a valley fill located in …

Automated System To Improve Levelness Of Reconstructed Soil, Venkata Srikiran Bodapati, Larry G. Wells

Biosystems and Agricultural Engineering Faculty Publications

Extraction of coal, ores, and minerals from the earth by surface mining has occurred for many years and has always presented a significant challenge with regard to restoration of productive soil to mined areas. Federal and state regulations require that land should be returned to pre-mine productivity or reclaimed as per specific standards following mining. Excessive compaction of reconstructed soil caused by traffic of heavy earth moving equipment has been an enduring challenge regarding successful restoration of soil. A mechanical system was previously designed and developed to reconstruct soil to a depth of 1.22 m (48 in.) while completely avoiding …

Methane And Carbon Dioxide Production From Simulated Anaerobic Degradation Of Cattle Carcasses, Qi Yuan, Samuel Saunders, Shannon L. Bartelt-Hunt

Department of Civil and Environmental Engineering: Faculty Publications

Approximately 2.2 million cattle carcasses require disposal annually in the United States. Land burial is a convenient disposal method that has been widely used in animal production for disposal of both daily mortalities as well as during catastrophic mortality events. To date, greenhouse gas production after mortality burial has not been quantified, and this study represents the first attempt to quantify greenhouse gas emissions from land burial of animal carcasses. In this study, anaerobic decomposition of both homogenized and unhomogenized cattle carcass material was investigated using bench-scale reactors. Maximum yields of methane and carbon dioxide were 0.33 and 0.09 m …

Berm Method For Quantification Of Infiltration And Leaching At The Plot Scale In High Conductivity Soils, Derek M. Heeren, Garey A. Fox, Daniel E. Storm

Biological Systems Engineering: Papers and Publications

Measuring infiltration and leaching at the plot scale is difficult, especially for high hydraulic conductivity soils. Infiltration rate has been indirectly calculated at the plot scale by comparing surface runoff to rainfall. Direct measurement of infiltration and leaching beyond the point scale is typically limited to locations where land forming has been performed, e.g. infiltration ponds and fields with basin irrigation. The standard method for field measurement of infiltration is a double ring infiltrometer, which is limited in size (typically 30 cm diameter). In this research, a new method is proposed that uses a temporary berm constructed of a water …