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 …

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 …

Precision Weed Management Based On Uas Image Streams, Machine Learning, And Pwm Sprayers, Jason Allen Davis

Graduate Theses and Dissertations

Weed populations in agricultural production fields are often scattered and unevenly distributed; however, herbicides are broadcast across fields evenly. Although effective, in the case of post-emergent herbicides, exceedingly more pesticides are used than necessary. A novel weed detection and control workflow was evaluated targeting Palmer amaranth in soybean (Glycine max) fields. High spatial resolution (0.4 cm) unmanned aircraft system (UAS) image streams were collected, annotated, and used to train 16 object detection convolutional neural networks (CNNs; RetinaNet, Faster R-CNN, Single Shot Detector, and YOLO v3) each trained on imagery with 0.4, 0.6, 0.8, and 1.2 cm spatial resolutions. Models were …

Modeling Actual Evapotranspiration With Msi-Sentinel Images And Machine Learning Algorithms, Robson Argolo Dos Santos, Everardo Chartuni Mantovani, Elpídio Inácio Fernandes-Filho, Roberto Filgueiras, Rodrigo Dal Sasso Lourenço, Vinícius Bof Bufon, Christopher M. U. Neale

Biological Systems Engineering: Papers and Publications

The modernization of computational resources and application of artificial intelligence algorithms have led to advancements in studies regarding the evapotranspiration of crops by remote sensing. Therefore, this research proposed the application of machine learning algorithms to estimate the ET_rF (Evapotranspiration Fraction) of sugar can crop using the METRIC (Mapping Evapotranspiration at High Resolution with Internalized Calibration) model with data from the Sentinel-2 satellites constellation. In order to achieve this goal, images from the MSI sensor (MultiSpectral Instrument) from the Sentinel-2 and the OLI (Operational Land Imager) and TIRS (Thermal Infrared Sensor) sensors from the Landsat-8 were acquired nearly …

Comparison Of Stationary And Mobile Canopy Sensing Systems For Irrigation Management Of Maize And Soybean In Nebraska, Sandeep Bhatti, Derek M. Heeren, Susan A. O’Shaughnessy, Steven R. Evett, Mitchell S Maguire, Suresh Pradhyun Kashyap, Christopher M. U. Neale

Biological Systems Engineering: Papers and Publications

Accurate knowledge of plant and field characteristics is crucial for irrigation management. Irrigation can potentially be better managed by utilizing data collected from various sensors installed on different platforms. The accuracy and repeatability of each data source are important considerations when selecting a sensing system suitable for irrigation management. The objective of this study was to compare data from multispectral (red and near-infrared bands) and thermal (long wave thermal infrared band) sensors mounted on different platforms to investigate their comparative usability and accuracy. The different sensor platforms included stationary posts fixed on the ground, the lateral of a center pivot …

Leveraging Unmanned Aerial System Remote Sensing To Inform Energy And Water Balance Models For Spatial Soil Water Content Monitoring And Irrigation Management, Mitchell S. Maguire

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

Irrigation has provided a means to produce more food and fiber throughout the world, converting low producing land into high yielding cropping systems in certain scenarios. The managing of irrigation has taken on various approaches as different locations have been constrained by different factors. Certain areas have significant ground and surface water available for irrigation while other areas struggle to meet irrigation demands due to limited water resources. These factors, along with the desire to increase crop water use efficiency, has provided the motivation to better understand crop water demands spatially within a field. A sub-field scale irrigation management study …

Classifying Reflectance Targets Under Ambient Light Conditions Using Passive Spectral Measurements, Ali Hamidisepehr, Michael P. Sama, Joseph S. Dvorak, Ole O. Wendroth, Michael D. Montross

Biosystems and Agricultural Engineering Faculty Publications

Collecting remotely sensed spectral data under varying ambient light conditions is challenging. The objective of this study was to test the ability to classify grayscale targets observed by portable spectrometers under varying ambient light conditions. Two sets of spectrometers covering ultraviolet (UV), visible (VIS), and near−infrared (NIR) wavelengths were instrumented using an embedded computer. One set was uncalibrated and used to measure the raw intensity of light reflected from a target. The other set was calibrated and used to measure downwelling irradiance. Three ambient−light compensation methods that successively built upon each other were investigated. The default method used a variable …

Site-Specific Irrigation Management In A Sub-Humid Climate Using A Spatial Evapotranspiration Model With Satellite And Airborne Imagery, Sandeep Bhatti, Derek M. Heeren, J. Burdette Barker, Christopher M. U. Neale, Wayne Woldt, Mitchell S. Maguire, Daran Rudnick

Biological Systems Engineering: Papers and Publications

Variable Rate Irrigation (VRI) considers spatial variability in soil and plant characteristics to optimize irrigation management in agricultural fields. The advent of unmanned aircraft systems (UAS) creates an opportunity to utilize high-resolution (spatial and temporal) imagery into irrigation management due to decreasing costs, ease of operation, and reduction of regulatory constraints. This research aimed to evaluate the use of UAS data for VRI, and to quantify the potential of VRI in terms of relative crop and water response. Irrigation treatments were: (1) VRI using Landsat imagery (VRI-L), (2) VRI using UAS imagery (VRI-U), (3) uniform (U), and (4) rainfed (R). …

Calibration Of A Common Shortwave Multispectral Camera System For Quantitative Agricultural Applications, J. Burdette Barker, Wayne Woldt, Brian Wardlow, Christopher Michael Usher Neale, Mitchell S. Maguire, Bryan Leavitt, Derek M. Heeren

Biological Systems Engineering: Papers and Publications

Unmanned aerial systems (UAS) for collecting multispectral imagery of agricultural fields are becoming more affordable and accessible. However, there is need to validate calibration of sensors on these systems when using them for quantitative analyses such as evapotranspiration, and other modeling for agricultural applications. The results of laboratory testing of a MicaSense (Seattle, WA, USA) RedEdge™ 3 multispectral camera and MicaSense Downwelling Light Sensor (irradiance sensor) system using a calibrated integrating sphere were presented. Responses of the camera and irradiance sensor were linear over many light levels and became non-linear at light levels below expected real-world, field conditions. Simple linear …

A Decade Of Unmanned Aerial Systems In Irrigated Agriculture In The Western U.S., Jose L. Chavez, Alfonso F. Torres-Rua, Wayne E. Woldt, Huihui Zhang, Christopher Robertson, Gary W. Marek, Dong Wang, Derek M. Heeren, Saleh Taghvaeian, Christopher M. U. Neale

Biological Systems Engineering: Papers and Publications

Several research institutes, laboratories, academic programs, and service companies around the United States have been developing programs to utilize small unmanned aerial systems (sUAS) as an instrument to improve the efficiency of in-field water and agronomical management. This article describes a decade of efforts on research and development efforts focused on UAS technologies and methodologies developed for irrigation management, including the evolution of aircraft and sensors in contrast to data from satellites. Federal Aviation Administration (FAA) regulations for UAS operation in agriculture have been synthesized along with proposed modifications to enhance UAS contributions to irrigated agriculture. Although it is feasible …

Variable Rate Irrigation Of Maize And Soybean In West-Central Nebraska Under Full And Deficit Irrigation, J Burdette Barker, Sandeep Bhatti, Derek M. Heeren, Christopher M.U. Neale, Daran Rudnick

Biological Systems Engineering: Papers and Publications

Variable rate irrigation (VRI) may improve center pivot irrigation management, including deficit irrigation. A remote-sensing-based evapotranspiration model was implemented with Landsat imagery to manage irrigations for a VRI equipped center pivot irrigated field located in West-Central Nebraska planted to maize in 2017 and soybean in 2018. In 2017, the study included VRI using the model, and uniform irrigation using neutron attenuation for full irrigation with no intended water stress (VRI-Full and Uniform-Full treatments, respectively). In 2018, two deficit irrigation treatments were added (VRI-Deficit and Uniform-Deficit, respectively) and the model was modified in an attempt to reduce water balance drift; model …

Performance Validation Of A Multi-Channel Lidar Sensor: Assessing The Effects Of Target Height And Sensor Velocity On Measurement Error, Surya S. Dasika, Michael P. Sama, L. Felipe Pampolini, Christopher B. Good

Biosystems and Agricultural Engineering Faculty Publications

The objective of this study was to determine the effects of sensor velocity and target height above ground level on height measurement error when using a multi-channel LiDAR sensor. A linear motion system was developed to precisely control the dynamics of the LiDAR sensor in an effort to remove uncertainty in the LiDAR position and velocity while under motion. The linear motion system allowed the LiDAR to translate forward and backward in one direction parallel to the ground. A user control interface was developed to operate the system under different velocity profiles and to log LiDAR data synchronous to the …

Fuzzy Control System For Variable Rate Irrigation Using Remote Sensing, Willians Ribeiro Mendes, Fábio Meneghetti U. Araújo, Ritaban Dutta, Derek M. Heeren

Biological Systems Engineering: Papers and Publications

Variable rate irrigation (VRI) is the capacity to spatially vary the depth of water application in a field to handle different types of soils, crops, and other conditions. Precise management zones must be developed to efficiently apply variable rate technologies. However, there is no universal method to determine management zones. Using speed control maps for the central pivot is one option. Thus, this study aims to develop an intelligent fuzzy inference system based on precision irrigation knowledge, i.e., a system that can create prescriptive maps to control the rotation speed of the central pivot. Satellite images are used in this …

Rapeseed Seedling Stand Counting And Seeding Performance Evaluation At Two Early Growth Stages Based On Unmanned Aerial Vehicle Imagery, Biquan Zhao, Jian Zhang, Chenghai Yang, Guangsheng Zhou, Youchun Ding, Yeyin Shi, Dongyan Zhang, Jing Xie, Qingxi Liao

Biological Systems Engineering: Papers and Publications

The development of unmanned aerial vehicles (UAVs) and image processing algorithms for field-based phenotyping offers a non-invasive and effective technology to obtain plant growth traits such as canopy cover and plant height in fields. Crop seedling stand count in early growth stages is important not only for determining plant emergence, but also for planning other related agronomic practices. The main objective of this research was to develop practical and rapid remote sensing methods for early growth stage stand counting to evaluate mechanically seeded rapeseed (Brassica napus L.) seedlings. Rapeseed was seeded in a field by three different seeding devices. A …

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 …

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 …

A Low-Cost Method For Collecting Hyperspectral Measurements From A Small Unmanned Aircraft System, Ali Hamidisepehr, Michael P. Sama

Biosystems and Agricultural Engineering Faculty Publications

Small unmanned aircraft systems (UAS) are a relatively new tool for collecting remote sensing data at dense spatial and temporal resolutions. This study aimed to develop a spectral measurement platform for deployment on a UAS for quantifying and delineating moisture zones within an agricultural landscape. A series of portable spectrometers covering ultraviolet (UV), visible (VIS), and near-infrared (NIR) wavelengths were instrumented using a Raspberry Pi embedded computer that was programmed to interface with the UAS autopilot for autonomous data acquisition. A second set of identical spectrometers were fitted with calibrated irradiance lenses to capture ambient light during data acquisition. Data …

Classifying Soil Moisture Content Using Reflectance-Based Remote Sensing, Ali Hamidisepehr

Theses and Dissertations--Biosystems and Agricultural Engineering

The ability to quantify soil moisture spatial variability and its temporal dynamics over entire fields through direct soil observations using remote sensing will improve early detection of water stress before crop physiological or economic damage has occurred, and it will contribute to the identification of zones within a field in which soil water is depleted faster than in other zones of a field.

The overarching objective of this research is to develop tools and methods for remotely estimating soil moisture variability in agricultural crop production. Index-based and machine learning methods were deployed for processing hyperspectral data collected from moisture-controlled samples. …

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 …

Rapeseed Seedling Stand Counting And Seeding Performance Evaluation At Two Early Growth Stages Based On Unmanned Aerial Vehicle Imagery, Biquan Zhao, Jian Zhang, Chenghai Yang, Guangsheng Zhou, Youchun Ding, Yeyin Shi, Dongyan Zhang, Jing Xie, Qingxi Liao

Biological Systems Engineering: Papers and Publications

The development of unmanned aerial vehicles (UAVs) and image processing algorithms for field-based phenotyping offers a non-invasive and effective technology to obtain plant growth traits such as canopy cover and plant height in fields. Crop seedling stand count in early growth stages is important not only for determining plant emergence, but also for planning other related agronomic practices. The main objective of this research was to develop practical and rapid remote sensing methods for early growth stage stand counting to evaluate mechanically seeded rapeseed (Brassica napus L.) seedlings. Rapeseed was seeded in a field by three different seeding devices. A …

Development Of The End-Effector Of A Cable-Driven Parallel Manipulator For Automated Crop Sensing, Iman Salafian

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

A four cable-driven parallel manipulator (4CDPM), consisting of sophisticated spectrometers and imagers, is under development for use in acquiring phenotypic and environmental data over an acre-sized maize field. This thesis presents the design, controls, and testing of two sub-systems in a 4CDPM: a Center of Mass Balance System (CMBS) and a Drop-Down System (DDS).

One of the factors that influences stability is the center of mass (COM) position of the end effector. An offset in COM can cause a pendulum effect or an undesired tilt angle. A center of mass balancing system is presented in this thesis to minimize the …

A Method For Reflectance Index Wavelength Selection From Moisture-Controlled Soil And Crop Residue Samples, Ali Hamidisepehr, Michael P. Sama, Aaron P. Turner, Ole O. Wendroth

Biosystems and Agricultural Engineering Faculty Publications

Reflectance indices are a method for reducing the dimensionality of spectral measurements used to quantify material properties. Choosing the optimal wavelengths for developing an index based on a given material and property of interest is made difficult by the large number of wavelengths typically available to choose from and the lack of homogeneity when remotely sensing agricultural materials. This study aimed to determine the feasibility of using a low-cost method for sensing the moisture content of background materials in traditional crop remote sensing. Moisture-controlled soil and wheat stalk residue samples were measured at varying heights using a reflectance probe connected …

Using Remote Sensing To Estimate Crop Water Use To Improve Irrigation Water Management, Arturo Reyes-Gonzalez

Electronic Theses and Dissertations

Irrigation water is scarce. Hence, accurate estimation of crop water use is necessary for proper irrigation managements and water conservation. Satellite-based remote sensing is a tool that can estimate crop water use efficiently. Several models have been developed to estimate crop water requirement or actual evapotranspiration (ETa) using remote sensing. One of them is the Mapping EvapoTranspiration at High Resolution using Internalized Calibration (METRIC) model. This model has been compared with other methods for ET estimations including weighing lysimeters, pan evaporation, Bowen Ratio Energy Balance System (BREBS), Eddy Covariance (EC), and sap flow. However, comparison of METRIC model outputs to …

Ecosystem Evapotranspiration: Challenges In Measurements, Estimates, And Modeling, D.M. Amatya, Suat Irmak, P. Gowda, G. Sun, J.E. Nettles, K.R. Douglas-Mankin

Biological Systems Engineering: Papers and Publications

Evapotranspiration (ET) processes at the leaf to landscape scales in multiple land uses have important controls and feed backs for local, regional, and global climate and water resource systems. Innovative methods, tools, and technologies for improved understanding and quantification of ET and crop water use are critical for adapting more effective management strategies to cope with increasing demand for freshwater resources under global climate change. This article introduces an ASABE Special Collection of 12 articles on ET monitoring and modeling research for multiple land uses and scales. The collection focuses on recent advances in four critical topical areas: (1) reference …

Informative Spectral Bands For Remote Green Lai Estimation In C3 And C4 Crops, Oz Kira, Anthony L. Nguy-Robertson, Timothy J. Arkebauer, Raphael Linker, Anatoly A. Gitelson

School of Natural Resources: Faculty Publications

Green leaf area index (LAI) provides insight into the productivity, physiological and phenological status of vegetation. Measurement of spectral reflectance offers a fast and nondestructive estimation of green LAI. A number of methods have been used for the estimation of green LAI; however, the specific spectral bands employed varied widely among the methods and data used. Our objectives were (i) to find informative spectral bands retained in three types of methods, neural network (NN), partial least squares (PLS) regression and vegetation indices (VI), for estimating green LAI in maize (a C4 species) and soybean (a C3 species); (ii) to assess …

Ecosystem Evapotranspiration: Challenges In Measurements, Estimates, And Modeling, D.M. Amatya, Sibel Irmak, P. Gowda, G. Sun, J.E. Nettles, K.R. Douglas-Mankin

Biological Systems Engineering: Papers and Publications

Evapotranspiration (ET) processes at the leaf to landscape scales in multiple land uses have important con- trols and feedbacks for local, regional, and global climate and water resource systems. Innovative methods, tools, and technologies for improved understanding and quantification of ET and crop water use are critical for adapting more effective management strategies to cope with increasing demand for freshwater resources under global climate change. This article introduces an ASABE Special Collection of 12 articles on ET monitoring and modeling research for multiple land uses and scales. The collection focuses on recent advances in four critical topical areas: (1) reference …

Estimating The Water Quality Condition Of River And Lake Water In The Midwestern United States From Its Spectral Characteristics, Jing Tan

Open Access Dissertations

This study focuses on developing/calibrating remote sensing algorithms for water quality retrieval in Midwestern rivers and lakes. In the first part of this study, the spectral measurements collected using a hand-held spectrometer as well as water quality observations for the Wabash River and its tributary the Tippecanoe River in Indiana were used to develop empirical models for the retrieval of chlorophyll (chl) and total suspended solids (TSS). A method for removing sky and sun glint from field spectra for turbid inland waters was developed and tested. Empirical models were then developed using a subset of the field measurements with the …

Evaluation Of A Hybrid Remote Sensing Evapotranspiration Model For Variable Rate Irrigation Management, J. Burdette Barker, Christopher M. U. Neale, Derek M. Heeren

Biological Systems Engineering: Papers and Publications

Accurate generation of spatial irrigation prescriptions is essential for implementation and evaluation of variable rate irrigation (VRI) technology. A hybrid remote sensing evapotranspiration (ET) model was evaluated for use in developing irrigation prescriptions for a VRI center pivot. The model is a combination of a two-source energy balance model and a reflectance based crop coefficient water balance model. Spatial ET and soil water depletion were modeled for a 10 km² area consisting of rainfed and irrigated maize fields in eastern Nebraska for 2013. Multispectral images from Landsat 8 Operational Land Imager and Thermal Infrared Sensor were used as model …

Integrating Remote Sensing Of Evapotranspiration With Applied Water To Target Potential Water Conservation Projects In Watersheds, Daniel J. Howes, Stuart Styles

BioResource and Agricultural Engineering

The overall purpose of the project is to develop a methodology for watershed managers to successfully target and release recommendations to growers that could benefit from improved on-farm irrigation management. Initially it was thought that the methodology could rely on remote sensing of actual crop evapotranspiration, effective rainfall estimates, and water application information (pumped volumes and surface water deliveries) to simply evaluate if fields and farms that applied significantly more water than plants needed could be identified. However, it became clear that, in this region specifically, additional information on water quality, crop sensitivity to salinity, and an assumed good irrigation …

Evaluating Net Groundwater Use From Remotely Sensed Evapotranspiration And Water Delivery Information, Daniel J. Howes, Charles M. Burt, Lucas Hoffman

BioResource and Agricultural Engineering

A detailed, comprehensive, and accurate identification of groundwater aquifer properties will likely never be fully achieved because of the high degree of variability and costs that testing involves. Furthermore, accurate estimates of boundary conditions are essential for groundwater modeling so that investigations of improved management scenarios can be conducted. The lack of key input values at the ground surface boundary limits the ability to accurately assess aquifer dynamics. Of major importance is actual evapotranspiration (water consumption or the loss of water to the atmosphere through transpiration and evaporation). The Irrigation Training and Research Center (ITRC) modified remotely sensed satellite imagery …