Bioresource and Agricultural Engineering Commons^™

Enhancing Urban Water Quality Through Biological-Chemical Treatment: Aquatic Macroinvertebrate Community And Temporal Chlorophyll-A Response, Matthew Chaffee

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

With a growing human population, urbanization is impeding a plethora of natural waterways. Of these, urban ponds play a vital role in nutrient sequestration, flood prevention, and habitat sanctuaries. However, nutrient loading can reduce habitat effectiveness and promote harmful algae blooms. To reduce internal nutrient loads, a biological-chemical treatment strategy consisting of floating treatment wetlands (FTWs) and lanthanum were applied to two urban retention ponds, Densmore and Wilderness Ridge Ponds. To measure effectiveness, chlorophyll-a samples were collected and correlated with Sentinel-2. A novel band algorithm termed 3BR1 produced a strong correlation (R² = 0.72) to physical chlorophyll-a …

Responses Of Maize To Different Irrigation Regimes In Semi-Arid Western Nebraska, Swathi Palle

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

As the “Cornhusker State”, Maize (Zea mays) is an important crop in Nebraska. However, farmers in the state are challenged by unstable supply of surface water and limited groundwater resources. A better understanding of maize's response to water stress that occurs at different growth stages can help implement the best irrigation practices that conserve water while maintaining yields. In this study, we conducted field experiments at the Panhandle Research, Extension, and Education Center to compare the responses of maize to eight irrigation treatments which included both limited and deficit irrigation regimes during 2022 and 2023 growing seasons. Specifically, …

Renovating The Ipmu Via Internet Of Things For Pollutant Emission Estimations In Poultry Facilities, Joshua Dotto

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

The emissions of ammonia (NH₃), particulate matter (PM_2.5), and carbon dioxide (CO₂) are major concerns in poultry facilities. They can pose environmental concerns and nuances. Robust and affordable measurement systems are needed to accurately measure in-barn concentrations and quantify the emissions.

The Intelligent Portable Monitoring Unit (iPMU or PMU3) developed in 2016 was reconstructed into PMU4 to include upgraded NH₃ and PM_2.5 sensors and wireless connectivity for a low-cost, robust, and accurate air quality monitoring device with contactless data transfer using the concept of Internet of Things (IoT). In addition, a user-friendly …

Assessment Of Integrated Nutrient Management Practices On Soil Health And Nitrogen Efficiency In Cropping Systems, María José Oviedo Ventura

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

Groundwater quality in Nebraska is threatened by non-point source contributions of nitrate-nitrogen, primarily by agricultural systems. Intensive crop and livestock production that neglects the value of manure in crop fertility plans can contribute to soil degradation and natural resource impairment. The purpose of this study is to evaluate opportunities to improve agricultural nutrient management throughout Nebraska by quantifying opportunities for manure distribution, evaluating soil health implications of organic and inorganic soil amendments, and assessing nutrient management practices focused on reducing nitrate leaching in agricultural soils.

This study described in Chapter 2 provides a spatial illustration of nitrogen and phosphorus balances …

Characterization Of Physical And Biochemical Traits In Wheat And Corn Plants Using High Throughput Image Analysis, Kantilata Thapa

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

Plant phenotyping has been recognized as a rapidly growing field of research due to the labor-intensive, destructive, and time-consuming nature of traditional phenotyping methods. These phenotyping bottlenecks can be addressed by advancements in image-based phenotyping like RGB and hyperspectral imaging for the assessment of plant traits important for breeding purposes. This study aims (1) to characterize the physical and biochemical traits of wheat and corn plants using RGB and hyperspectral imaging in the greenhouse, and (2) to estimate leaf nitrogen (N), phosphorus (P), and potassium (K) content using hyperspectral imaging and an analytical spectral device (ASD spectrometer) and compare the …

Inactivation Of Salmonella In Black Peppercorn By Fluidization With Hydrogen Peroxide Vapor, Edel Summers

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

The purpose of the present study was to assess the effectiveness of hydrogen peroxide vapor (HPV) at inactivating Salmonella inoculated in whole black pepper when used as fluidizing gas media. HPV treatment was conducted at two different temperatures (45°C and 60°C) and two dwell times (30 min and 60 min). Microbial reduction and residual hydrogen peroxide were measured at three storage times: 0 h (immediately after treatment), 24 h and 48 h post-treatment. The effect of HPV on the quality of whole black peppercorn was evaluated 48 h post-treatment based on changes in piperine content, total phenolics, antioxidant activity, total …

Improving Microbiological Safety Of Low Moisture Food Products Using Radio Frequency And Ethylene Oxide, Long Chen

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

Recent foodborne illness outbreaks in US associated with consumption of low-moisture foods (LMF) have heightened concerns of their microbial safety. Salmonella is a pathogen of major concern in LMF due to its ability to persist in low water activity (a_w) environments. The disadvantages of existing decontamination technologies for LMF call for novel and efficient intervention technologies. Radio frequency (RF) and ethylene oxide (EtO) were evaluated in this dissertation for improving microbial food safety and quality of LMF. Cumin seeds and inshell hazelnuts were selected as model foods.

It took < 2 min of stationary RF heating to achieve > 5 log reductions of Salmonella in cumin seeds without …

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

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

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

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

Mid To Late Season Weed Detection In Soybean Production Fields Using Unmanned Aerial Vehicle And Machine Learning, Arun Narenthiran Veeranampalayam Sivakumar

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

Mid-late season weeds are those that escape the early season herbicide applications and those that emerge late in the season. They might not affect the crop yield, but if uncontrolled, will produce a large number of seeds causing problems in the subsequent years. In this study, high-resolution aerial imagery of mid-season weeds in soybean fields was captured using an unmanned aerial vehicle (UAV) and the performance of two different automated weed detection approaches – patch-based classification and object detection was studied for site-specific weed management. For the patch-based classification approach, several conventional machine learning models on Haralick texture features were …

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 …

High Throughput In Vivo Analysis Of Plant Leaf Chemical Properties Using Hyperspectral Imaging, Piyush Pandey, Yufeng Ge, Vincent Stoerger, James C. Schnable

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

The possibility of predicting plant leaf chemical properties using hyperspectral images was studied. Sixty maize and 60 soybean plants were used, and two experiments were conducted: one with water limitation and the second with nutrient limitation, with the purpose of creating wide ranges of these chemical properties in plant leaf tissues. A hyperspectral imaging system with a spectral range from 550 to 1700 nm was used to acquire plant images in a high throughput fashion (plants placed on an automated conveyor belt). Leaf chemical properties were measured in the laboratory. Partial least squares regression was implemented on spectral data to …

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 …

Using A Vnir Spectral Library To Model Soil Carbon And Total Nitrogen Content, Nuwan K. Wijewardane

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

n-situ soil sensor systems based on visible and near infrared spectroscopy is not yet been effectively used due to inadequate studies to utilize legacy spectral libraries under the field conditions. The performance of such systems is significantly affected by spectral discrepancies created by sample intactness and library differences. In this study, four objectives were devised to obtain directives to address these issues. The first objective was to calibrate and evaluate VNIR models statistically and computationally (i.e. computing resource requirement), using four modeling techniques namely: Partial least squares regression (PLS), Artificial neural networks (ANN), Random forests (RF) and Support vector regression …

Infiltration And Runoff Parameters For Tilled And No-Till Row Crops, Andrew J. Volkmer

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

Infiltration and runoff are hydrologic processes that effect the amount of water available to plants, for groundwater recharge, and for stream flow. No-till planting (NT) is a management practice used to reduce soil erosion, increase water infiltration, and reduce soil water evaporation, and can have great impact on infiltration and runoff. An investigation was conducted to determine the impact of NT on infiltration and runoff when compared to tilled conditions.

Runoff and precipitation data was gathered from sites at Fillmore County, NE, Phelps County, NE, the USDA-ARS North Appalachian Experimental Watersheds (NAEW) near Coshocton, OH, and the Lennoxville Research Station …

Characterization Of Genetically Modified High Biomass Producing Tobacco Plant, Pankaj Singh Kuhar

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

Global warming and peak oil has clouded our energy security. In light of this situation, bioethanol as emerged as one of the most amenable solutions to the problem. However bioethanol has its own shortcomings and transgenics seem imperative to exploit its full potential. A high biomass producing line in transgenic tobacco (Nicotiana tabacum cv. Xanthi) was identified during a routine genetic transformation, termed giant recombinant (GR). To characterize the phenotype of the giant line, growth rate and lignocellulosic composition was analyzed relative to the non-transgenic control line. The GR line accounted for 240% more biomass than the untransformed line …

Biomass Gasification: An Alternative Solution To Animal Waste Management, Hanjing Wu

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

The overall goal of this research was to evaluate gasification of animal waste as an alternative manure management strategy, from the standpoints of syngas production and biochar application.

To meet the overall objective, the thermogravimetric characteristics of dairy manure, as a thermochemical conversion feedstock, were studied firstly. Then, gasification technology was applied to dairy manure and feedlot manure using a fluidized-bed laboratory-scale gasifier. In addition, biochar derived from the feedlot manure was examined for its effects on nutrient leaching as a soil amendment. Finally, a life cycle assessment was conducted to evaluate greenhouse gas emissions of two feedlot manure management …

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 …

Identifying Changes In Climatic Trends And The Fingerprints Of Landuse And Landcover Changes In The High Plains Of The Usa, Denis Mutiibwa

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

Human activities such as conversion of natural ecosystem to croplands and urban-centers, deforestation and afforestation impact biophysical properties of land surface such as albedo, energy balance, and surface roughness. Alterations in these properties affect the heat and moisture exchanges between the land surface and atmospheric boundary layer. The objectives of this research were; (i) to quantitatively identify the High plains’ regional climate change in temperatures over the period 1895 to 2006, (ii) detect the signatures of anthropogenic forcing of LULC changes on the regional climate change of the High Plains, and (iii) examine the trends in evolving regional latent heat …