Bioresource and Agricultural Engineering Commons^™

Differences In Soil Biological Activity By Terrain Types At The Sub-Field Scale In Central Iowa Us, Amy L. Kaleita, Linda R. Schott, Sarah K. Hargreaves, Kirsten S. Hofmockel

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Soil microbial communities are structured by biogeochemical processes that occur at many different spatial scales, which makes soil sampling difficult. Because soil microbial communities are important in nutrient cycling and soil fertility, it is important to understand how microbial communities function within the heterogeneous soil landscape. In this study, a self-organizing map was used to determine whether landscape data can be used to characterize the distribution of microbial biomass and activity in order to provide an improved understanding of soil microbial community function. Points within a row crop field in southcentral Iowa were clustered via a self-organizing map using six …

A Case Study Of Field-Scale Maize Irrigation Patterns In Western Nebraska: Implications For Water Managers And Recommendations For Hyper-Resolution Land Surface Modeling, Justin P. Gibson, Trenton E. Franz, Tiejun Wang, John Gates, Patricio Grassini, Haishun Yang, Dean E. Eisenhauer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In many agricultural regions, the human use of water for irrigation is often ignored or poorly represented in land surface models (LSMs) and operational forecasts. Because irrigation increases soil moisture, feedback on the surface energy balance, rainfall recycling, and atmospheric dynamics is not represented and may lead to reduced model skill. In this work, we describe four plausible and relatively simple irrigation routines that can be coupled to the next generation of hyper-resolution LSMs operating at scales of 1 km or less. The irrigation output from the four routines (crop model, precipitation delayed, evapotranspiration replacement, and vadose zone model) is …

The Assessment Of Water Resources In Ungauged Catchments In Rwanda, O. P. Abimbola, J. Wenninger, R. Venneker, Aaron R. Mittelstet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Study region: Rwanda is a landlocked country in Africa with precipitation ranging from 800 mm yr−1 in the east to 1500 mm yr−1 in high-altitude regions in the north and west. Study focus: Streamflow estimation is an important task that is required in water resource assessments due to its importance in planning, decision-making and economic development. In this study, streamflow characteristics of ungauged catchments in Rwanda were calculated using a regionalization approach based on climate similarity and stepwise multiple-regression analysis. One climatic homogeneous region was identified and datasets of nine gauged stations and general available catchment characteristics were …

A Geospatial Variable Rate Irrigation Control Scenario Evaluation Methodology Based On Mining Root Zone Available Water Capacity, K. A. Miller, Joe Luck, Derek M. Heeren, T. Lo, Derrel Martin, J. B. Barker

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Increasing concern for sustainable water use has the agriculture industry working toward higher efficiency in use of irrigation water. Recent advancements have improved the capabilities of center pivot irrigation systems to vary water application depths across the field, a technology known as variable rate irrigation (VRI). The goal of this study was to provide a geospatial method for potential VRI technology adopters to evaluate control scenarios and potential water savings using freely available datasets. Root zone available water capacity (R) was estimated spatially across two case study fields using the Natural Resources Conservation Service Gridded Soil Survey Geographic Database. The …

Crop Classification And Lai Estimation Using Original And Resolution-Reduced Images From Two Consumer-Grade Cameras, Jian Zhang, Chenghai Yang, Biquan Zhao, Huaibo Song, Wesley Clint Hoffmann, Yeyin Shi, Dongyan Zhang, Guozhong Zhang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Consumer-grade cameras are being increasingly used for remote sensing applications in recent years. However, the performance of this type of cameras has not been systematically tested and well documented in the literature. The objective of this research was to evaluate the performance of original and resolution-reduced images taken from two consumer-grade cameras, a RGB camera and a modified near-infrared (NIR) camera, for crop identification and leaf area index (LAI) estimation. Airborne RGB and NIR images taken over a 6.5-square-km cropping area were mosaicked and aligned to create a four-band mosaic with a spatial resolution of 0.4 m. The spatial resolution …

Nanoparticle For Targeting Brain Tumors And Delivery Of O6 - Benzylguanine, University Of Washington, Seattle

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Nanoparticle having a crosslinked chitosan - polyethylene oxide oligomer copolymer coating to which O⁶ - benzylgua nine is covalently coupled , compositions that include the nanoparticle , and methods for using the nanoparticle to treat brain cancers .

The Effect Of Single-Handed Lifting Tasks On The Activation Of The Neck-Shoulder Shared Musculature, Mohamed R. Amar, David Cochran, Jeffrey Woldstad

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The use of the hand in lifting has been linked to occupational injuries of the neck and shoulder. This research is aimed at examining the effect of work-related factors on the major neck-shoulder shared musculature activity on both sides of the cervical spine for a right-handed lifting task. Subjects lifted different weights from 20 different locations produced by the interaction of varying heights, reach distance, and angles simulating the work done by assembly line workers. All lifting tasks were done by the right hand. Bilateral electromyography data of major shared musculature (upper trapezius, sternocleidomastoid, and levator scapula) were collected using …

Regulation-Structured Dynamic Metabolic Model Provides A Potential Mechanism For Delayed Enzyme Response In Denitrification Process, Hyun-Seob Song, Dennis G. Thomas, James C. Stegen, Minjing Li, Chongxuan Liu, Xuehang Song, Xingyuan Chen, Jim K. Fredrickson, John M. Zachara, Timothy D. Scheibe

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In a recent study of denitrification dynamics in hyporheic zone sediments, we observed a significant time lag (up to several days) in enzymatic response to the changes in substrate concentration. To explore an underlying mechanism and understand the interactive dynamics between enzymes and nutrients, we developed a trait-based model that associates a community’s traits with functional enzymes, instead of typically used species guilds (or functional guilds). This enzyme-based formulation allows to collectively describe biogeochemical functions of microbial communities without directly parameterizing the dynamics of species guilds, therefore being scalable to complex communities. As a key component of modeling, we accounted …

Performance Of Twelve Mass Transfer Based Reference Evapotranspiration Models Under Humid Climate, Koffi Djaman, Komlan Koudahe, Mamadou Sall, Isa Kabenge, Daran Rudnick, Suat Irkmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Reference evapotranspiration is very important parameter in the hydrological, agricultural and environmental studies and is accurately estimated by the FAO Penman-Monteith equation (FAO-PM) under different climatic conditions. However, due to data requirement of the FAO-PM equation, there is a need to investigate the applicability of alternative ETo equations under limited data. The objectives of this study were to evaluate twelve mass transfer based reference evapotranspiration equations and determine the impact of ETo equation on long term water management sustainability in Tanzania and Kenya. The results showed that the Albrecht, Brockamp-Wenner, Dalto, Meyer, Rohwer and Oudin ETo equations systematically overestimated the …

Evaluation Of Valiantzas’ Simplified Forms Of The Fao-56 Penman-Monteith Reference Evapotranspiration Model In A Humid Climate, Koffi Djaman, Daran Rudnick, Valere C. Mel, Denis Mutiibwa, Lamine Diop, Mamadou Sall, Isa Kabenge, Ansoumana Bodian, Hossein Tabari, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The unavailability of some meteorological variables, especially solar radiation and wind speed, is the main constraint for reference evapotranspiration (ETo) estimation using the standard United Nations Food and Agriculture Organization (FAO) Penman–Monteith (FAO-PM) equation in most developing countries. The application of ETo methods with fewer input requirements is necessary under limited climatic data conditions. The FAO-PM method under limited data conditions and nine of Valiantzas’ equations were evaluated for daily ETo estimation in a humid climate in Uganda. The FAO-PM method with missing relative humidity data performed very well across Uganda, whereas using the long-term local wind speed average values …

Crop Canopy Sensor Orientation For Late Season Nitrogen Determination In Corn, T. M. Shaver, Greg Kruger, Daran Rudnick

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Increasing nitrogen use efficiency (NUE) in irrigated corn production is of great importance to overall agricultural sustainability. Studies have shown that crop canopy sensors can aid in this pursuit as they allow for the determination of nitrogen (N) requirements in split applications later in the growing season. Fertigation can also increase NUE as many split applications can be conducted. If crop canopy sensors could be used to direct N fertigation rates, overall NUE may be increased even further. However, in some cases, N differences may need to be determined later in the growing season after corn has tasseled, which can …

Biofuels From Crop Residue: Soil Organic Carbon And Climate Impacts In The Us And India, Adam J. Liska

Adam Liska Papers

Soil organic carbon (SOC) levels are the balance of carbon inputs from plant material and loss from oxidation to CO₂ (SOC = I_C - kC_oc) SOC tends to decrease as atmospheric temperature increases.

In the US, SOC levels are highest in the north central region (Iowa) where maize & soybean are grown at high yields.

In the US, gross energy yield of biofuel production can be increased by using both maize grain & maize residue.

Are the US results relevant for India if crop residues are used for biofuels?

India’s estimated biomass production & potential in …

Spatial And Temporal Changes In Maize And Soybean Grain Yield, Precipitation Use Efficiency, And Crop Water Productivity In The U.S. Great Plains, Meetpal S. Kukal, S. Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Sustainable agricultural utilization of the limited water resources demands improvements in understanding the changes in crop water productivity (CWP) in space and time, which is often presented as a potential solution to relieve the growing pressure on fresh water resources. In addition, crop yield needs to be studied in relation to precipitation received annually and during the growing season for its contribution to reduce irrigation water requirements, which is quantified through precipitation use efficiency (PUE). Hence, systematic quantifications, mapping, and analyses of large-scale CWP and PUE levels are needed. This study aims to quantify long-term (1982-2013) information on grain yield, …

Large Co2 And Ch4 Emissions From Polygonal Tundra During Spring Thaw In Northern Alaska, Naama Raz-Yaseef, Margaret S. Torn, Yuxin Wu, David P. Billesbach, Anna K. Liljedahl, Timothy J. Kneafsey, Vladimir E. Romanovsky, David R. Cook, Stan D. Wullschleger

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The few prethaw observations of tundra carbon fluxes suggest that there may be large spring releases, but little is known about the scale and underlying mechanisms of this phenomenon. To address these questions, we combined ecosystem eddy flux measurements from two towers near Barrow, Alaska, with mechanistic soil-core thawing experiment. During a 2 week period prior to snowmelt in 2014, large fluxes were measured, reducing net summer uptake of CO₂ by 46% and adding 6% to cumulative CH₄ emissions. Emission pulses were linked to unique rain-on-snow events enhancing soil cracking. Controlled laboratory experiment revealed that as surface ice …

Estimation And Utilization Of Landfill Gas From Egyptian Municipal Wastes, A Case Study, Ali Habib, Ahmed A. Abdel-Rehim

Mechanical Engineering

Purpose

As the first Author had the chance to invest in landfill gas plant (EL Hammam plant) that flare approximately 1000 m3/hr. to generate electricity. Two critical question must be answered in order to proceed with the feasibility study. The three questions are:

1. 1- How many years this landfill gas emission will last?

2. 2- How much energy can be generated from one million ton if landfilled?

3. 3- How much CO2 in tons will be saved during the project life time?

Methods: Experimental method is used to determine BMP (Biochemical methane potential) ton CH4/ton waste. With

results we can know the …

Design And Plan Of A Modified Hydroponic Shipping Container For Research, John A. Houtman

Open Access Theses

As the world’s population continues to increase, food production will need to increase in order to meet the predicted rise in food demand. However, with increased pressure on cropland available from environmental effects and urbanization, new innovative methods of crop production need to be researched in order to increase agricultural production with limited land. This research focuses on the design of a single form of urban agriculture that is considered Zfarming and has the potential to produce quality urban agricultural produce through ground-based measures. This project produced detailed step-by-step analysis of the design process, develop variability within the modified hydroponic …

Exploring The Cause Of Injury Or Death In Grain Entrapment, Engulfment And Extrication, Salah F. Issa

Open Access Dissertations

Grain entrapments and engulfments are one of most common hazards associated with grain storage facilities. Since the 1970’s over 1,880 incidents have been documented in agricultural confined spaces of which 65% of all recorded incidents were grain entrapments and engulfments. There have been several studies conducted on the contributing factors behind these incidents; however, there have been very few attempts to understand the environmental, physiological or psychological factors the victims experience while entrapped, engulfed, or extricated. This includes understanding how secondary injuries are caused by grain or during extrication by first responders. The research effort was divided into three segments. …

Investigation Of Methods For Reducing Aflatoxin Contamination In Distillers Grains, Hu Shi

Open Access Dissertations

The overall goal of this project was to reduce the aflatoxin level in the final coproduct of ethanol bioprocessing--DDGS. This was pursued by examining the effects of reduction of aflatoxin in the incoming corn prior to bioprocessing, the degradation of aflatoxin in the intermediate products, namely DWG and CDS, during processing, and aflatoxin degradation in the DDGS. Segregation techniques (size screening and density sorting) and detoxification methods (conventional and microwave heating, food additives, and high voltage atmospheric cold plasma) were evaluated for their effectiveness in aflatoxin reduction.

Effectiveness of physical segregation of aflatoxin contaminated corn was investigated by size screening …

Characterization Of Ground Nozzles For Pesticide Applications, Ryan Henry

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

Pesticide applications are a common component of crop production systems in the United States (US). For row crop systems (e.g. corn, soybean, or wheat), pesticides are applied by ground, aerial, or chemigation methods. The exact method of pesticide delivery is not universally regulated/ prescribed in the US, and the equipment and application technique are largely defined by the individual applicator. A wide variety of choices and decisions must be made by applicators to result in a successful pesticide application. Examples of these choices include proper active ingredient(s), carrier volume and equipment (e.g. nozzle type, spacing, and operating pressure) selection while …

Deployment And Evaluation Of An Active Rfid Tracking System For Precision Animal Management, Brian Barnes

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

A better understanding of animal space utilization in current livestock facilities could lead to improved facility design and animal health. This study was conducted to determine whether an active RFID tag tracking system could accurately provide animal locomotion data on an individual animal basis. The system is composed of four sensors, located in the corners of a swine pen, and compact tags, which attach to the animals and transmit a signal. The sensors use the tag signals to determine 3-D positions in real-time. A data acquisition system was developed to capture raw data from the system software into a database …