The Fluxnet2015 Dataset And The Oneflux Processing Pipeline For Eddy Covariance Data,
2020
Lawrence Berkeley National Laboratory, Berkeley, CA
The Fluxnet2015 Dataset And The Oneflux Processing Pipeline For Eddy Covariance Data, Gilberto Pastorello, Timothy Arkebauer, Dave P. Billesbach, Anatoly Gitelson, Adam Liska, Andrew Suyker, Elizabeth Walter-Shea, More Than 200 Other
Adam Liska Papers
The FLUXNET2015 dataset provides ecosystem-scale data on CO2, water, and energy exchange between the biosphere and the atmosphere, and other meteorological and biological measurements, from 212 sites around the globe (over 1500 site-years, up to and including year 2014). These sites, independently managed and operated, voluntarily contributed their data to create global datasets. Data were quality controlled and processed using uniform methods, to improve consistency and intercomparability across sites. The dataset is already being used in a number of applications, including ecophysiology studies, remote sensing studies, and development of ecosystem and Earth system models. FLUXNET2015 includes derived-data products, such as …
The Temporal And Spatial Dynamics Of Fluvial Carbon Cycling In Irish Blanket Peatland Pools And Soils,
2020
Technological University Dublin
The Temporal And Spatial Dynamics Of Fluvial Carbon Cycling In Irish Blanket Peatland Pools And Soils, Mariya Radomski
Doctoral
Blanket peatlands in Ireland are reservoirs of organic matter and have effects on carbon dioxide (CO2) flux regulation. Data on dissolved CO2 in Ireland is limited. In blanket peatlands, the drainage systems are well connected with pools, hummocks and lawns and this connectivity leads to significant variations in outflows of carbon. The excess carbon dioxide in blanket peatlands could originate from soil organic matter decomposition. Dissolved CO2 could be transported into pools via surface run-off and lateral throughflow. Peatland pools are typically supersaturated in CO2. As part of a project described in this thesis, the role of spatial and seasonal …
Integrated Techno-Economic And Life Cycle Analyses Of Biomass Utilization For Value-Added Bioproducts In The Northeastern United States,
2020
West Virginia University
Integrated Techno-Economic And Life Cycle Analyses Of Biomass Utilization For Value-Added Bioproducts In The Northeastern United States, Yuxi Wang
Graduate Theses, Dissertations, and Problem Reports (ETD)
A multi-stage spatial analysis was first conducted to select locations for lignocellulosic biomass-based bioproduct facility, using Geographical Information System (GIS) spatial analysis, multi-criteria analysis ranking algorithm, and social-economic assessment. A case study was developed to determine locations for lignocellulosic biorefineries using feedstocks including forest residue biomass and three energy crops for 13 states in the northeastern United States. In the entire study area, 11.1% of the counties are high-suitable, 48.8% are medium-suitable for biorefinery siting locations. A non-parametric analysis of cross-group surveys showed that preferences on biorefinery siting are homogeneous for experts in academia and industry groups, but people in …
Nematode Populations As Affected By Residue And Water Management In A Long-Term Wheat-Soybean Double Crop In Eastern Arkansas,
2019
University of Arkansas, Fayetteville
Nematode Populations As Affected By Residue And Water Management In A Long-Term Wheat-Soybean Double Crop In Eastern Arkansas, Lucia Emperatriz Escalante Ortiz
Graduate Theses and Dissertations
Soybeans (Glycine max) are one of the major row crops in the United States, particularly in Arkansas. Soybean cyst nematode (SCN, Heterodera glycines) and southern root-knot nematode (RKN, Meloidogyne incognita) are two of the most damaging pests that cause major economic losses in soybeans. Little is known concerning the effects of common and alternative agronomic practices on nematodes in fields with nematode population densities below threshold levels. Therefore, the objective of this study was to evaluate the effects of the combination of tillage (conventional tillage and no-tillage), irrigation (irrigated and non-irrigated), wheat (Triticum aestivum) residue burning (burned and no burned), …
Drivers Of On-Farm Performance Of Irrigation Water Management Practices: Empirical Evidence From Eastern Arkansas,
2019
University of Arkansas, Fayetteville
Drivers Of On-Farm Performance Of Irrigation Water Management Practices: Empirical Evidence From Eastern Arkansas, Jacob Askey
Biological and Agricultural Engineering Undergraduate Honors Theses
Unsustainable agricultural practices are putting a strain on freshwater supplies in many parts of the world. More efficient irrigation techniques are going to be critical to feed a growing population. Data from the 2016 Arkansas Irrigation Survey was used to assess the adoption of three Irrigation Water Management (IWM) practices: multiple inlet rice irrigation, tailwater recovery, and storage reservoirs. Results indicate that these practices do not always lead to reported pumping time reductions, a proxy for water use savings. Large variations in pumping time reduction are observed across producers for all three practices. A Tobit model was used to examine …
Persistence And Mitigation Of Antibiotic Resistance In Manure And Manure-Amended Soils,
2019
University of Nebraska-Lincoln
Persistence And Mitigation Of Antibiotic Resistance In Manure And Manure-Amended Soils, Mara J. Zelt
Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research
The emergence of antibiotic resistance (AR) is a growing global threat to human and animal health. The work described here asses the AR mitigation potential of management strategies at critical control points in livestock production, and agricultural land management as well as the effectiveness of a communication strategy to convey research-based information to empower behavioral change that could mitigate AR.
The first study evaluates the impact of beef cattle diet management strategies on AMR prevalence in manure. Two treatments – forage concentration and essential oils – in cattle diets were evaluated for their impact on AMR bacteria in feedlot manure. …
Flex-Ro: A Robotic High Throughput Field Phenotyping System,
2019
University of Nebraska-Lincoln
Flex-Ro: A Robotic High Throughput Field Phenotyping System, Joshua N. Murman
Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research
Research in agriculture is critical to developing techniques to meet the world’s demand for food, fuel, fiber, and feed. Optimization of crop production per unit of land requires scientists across disciplines to collaborate and investigate new areas of science and tools for data collection. The use of robotics has been adopted in several industries to supplement labor, and accurately perform repetitious tasks. However, the use of autonomous robots in commercial agricultural production is still limited. The Flex-Ro (Flexible structured Robotic platform) was developed for use in large area fields as a multipurpose tool to perform monotonous agricultural tasks.
This work …
Predicting Agricultural Implement Hydraulic Power Demand Using Synchronized Controller Area Network And Ancillary Sensor Data,
2019
University of Nebraska-Lincoln
Predicting Agricultural Implement Hydraulic Power Demand Using Synchronized Controller Area Network And Ancillary Sensor Data, Gabriel P. Stoll
Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research
As agricultural implement designs have progressed in recent years, there has been an increase in hydraulic power demand from the tractor. Current power estimation standards do not accurately estimate hydraulic power demand for implements designed with higher hydraulic power requirements. Several stakeholders, including agricultural producers, tractor and implement manufacturers, and government agencies would benefit from accurate published data on these power requirements.
While an increasing amount of operational data available on the Controller Area Network (CAN) of tractors has assisted researchers in more easily obtaining machinery performance data, hydraulic control valve flow rate and pressure measurements are not currently publically …
Adding Value To Lignocellulosic Biorefinery: Efficient Process Development Of Lignocellulosic Biomass Conversion Into Polyhydroxybutyrate,
2019
University of Nebraska-Lincoln
Adding Value To Lignocellulosic Biorefinery: Efficient Process Development Of Lignocellulosic Biomass Conversion Into Polyhydroxybutyrate, Mengxing Li
Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research
Polyhydroxybutyrate (PHB) is bacteria synthesized polymer that has comparable mechanical properties as petroleum-based plastics and high biocompatibility. Current commercial PHB production process is not cost effective. Raw materials make up about 50% of the production cost. Lignocellulosic biomass are cheap, abundant feedstocks that can be converted into PHB to add profit and sustainability to lignocellulosic biorefinery. Lignocellulosic biorefinery upstream process produces polymeric sugar rich stream and lignin-enriched stream. Polymeric sugars are then hydrolyzed into a sugar stream with glucose, xyloseand arabinose mainly present. To the best of the author’s knowledge, limited studies have been done on sugar mixture conversion into …
Investigations Of Thermal Treatment Of Softwood Kraft Lignin Under Fractional And Ablative Pyrolytic Conditions,
2019
Louisiana State University and Agricultural and Mechanical College
Investigations Of Thermal Treatment Of Softwood Kraft Lignin Under Fractional And Ablative Pyrolytic Conditions, Dideolu J. Daniel
LSU Master's Theses
Lignin is second to cellulose in abundance among polymers in nature. Research studies on the development of new products and material combinations in which lignin degradation/conversion products are involved are still in their infancy, because fundamental knowledge about its structure, reactivity, and material and polymer behavior, is still lacking.
The objective of this research study was to investigate the complex thermal deconstruction and mechanistic behavior of a type of technical lignin, known as Kraft lignin, under depolymerization and to develop operating conditions for parameters influencing resulting product yields and operation of pyrolysis reactors.
Softwood Kraft lignin (s-KL) and methanol-fractionated (ex-KL) …
Low Flow Testing,
2019
California Polytechnic State University, San Luis Obispo
Low Flow Testing, Daniel J. Howes
BioResource and Agricultural Engineering
In arid environments, streamflow enhancement in low flow channels is common. It is challenging to assess enhancement project effectiveness in these channels because of uncertainties in metering (regarding both meters and procedures). The basic equation for flow is:
Q = VA (Eq. 1)
Where,
Q = channel flow rate (e.g., cubic feet per second, CFS)
V = cross sectional average velocity (e.g., feet per second, fps)
A = cross sectional area (e.g., square feet, ft2)
There are three main factors that impact flow measurement uncertainty in natural channels:
1. Flow meter velocity measurements (V)
2. Depth and area measurements (A) …
Variable Rate Irrigation Of Maize And Soybean In West-Central Nebraska Under Full And Deficit Irrigation,
2019
University of Nebraska-Lincoln
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
Department of Agricultural and Biological Systems Engineering: Faculty 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 …
Origins Of Space Food From Mercury To Apollo,
2019
Purdue University
Origins Of Space Food From Mercury To Apollo, Celine Chang
The Journal of Purdue Undergraduate Research
No abstract provided.
Nitrate Removal And Placement Of Floating Treatment Wetlands In The Midwest,
2019
University of Nebraska-Lincoln
Nitrate Removal And Placement Of Floating Treatment Wetlands In The Midwest, Mary G. Keilhauer
School of Natural Resources: Dissertations, Theses, and Student Research
The Midwestern United States is vulnerable to eutrophic conditions from high nutrient concentrations. Recommendations for nonpoint source pollution management include runoff treatment (i.e., filter strips, riparian buffers) and in-situ lake treatment practices (i.e., aluminum sulfate (alum) treatments, aeration, up/downdraft pumping, floating treatment wetlands). Floating treatment wetlands (FTWs) are an innovative wetland design for nutrient removal from nonpoint sources and provide a unique in-situ treatment. Best management practice studies have commonly focused on adjacent to water practices, which have resulted in a gap for guidance for in-situ treatment placement and design. Therefore, the objectives of this project were to (1) Quantify …
Purification Of Biomass Hydrolyzates For The Promotion Of Xylose Diester Formation,
2019
University of Louisville
Purification Of Biomass Hydrolyzates For The Promotion Of Xylose Diester Formation, Laura Fernandez
Electronic Theses and Dissertations
The application of a novel xylose isolation procedure using phenyl boronic acid esterification has been limited to the hydrolyzates of low extractive biomasses like hardwoods and agricultural resides. Hydrolyzates with lower sugar and higher extractive concentrations, like softwoods, have not yielded xylose, or even xylose diester (XDE), the first intermediate product in the new process, under the same conditions. This research applied evaporation concentration, adsorbent separation and membrane filtration to these lower performing biomass hydrolyzates to maximize the yield of the XDE formation step of the new xylose extraction process. Lab-scale tests of these techniques were applied to pine hydrolyzate …
Mid To Late Season Weed Detection In Soybean Production Fields Using Unmanned Aerial Vehicle And Machine Learning,
2019
University of Nebraska-Lincoln
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 …
Design, Development, And Field Testing A Visnir Integrated Multi-Sensing Soil Penetrometer,
2019
University of Nebraska-Lincoln
Design, Development, And Field Testing A Visnir Integrated Multi-Sensing Soil Penetrometer, Nuwan K. Wijewardane
Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research
The research community in soil science and agriculture lacks a cost-effective and rapid technology for in situ, high resolution vertical soil sensing. Visible and near infra-red (VisNIR) technology has the potential to be used for such sensor development due to its ability to derive multiple soil properties rapidly using a single spectrum. Such efforts must, however, overcome a few challenges: (i) a dry ground soil spectral library that can be used to predict the target soil properties accurately, (ii) a robust design which can acquire high quality VisNIR spectra of soil, (iii) an effective method that can link field intact …
A Multi-Sensor Phenotyping System: Applications On Wheat Height Estimation And Soybean Trait Early Prediction,
2019
University of Nebraska-Lincoln
A Multi-Sensor Phenotyping System: Applications On Wheat Height Estimation And Soybean Trait Early Prediction, Wenan Yuan
Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research
Phenotyping is an essential aspect for plant breeding research since it is the foundation of the plant selection process. Traditional plant phenotyping methods such as measuring and recording plant traits manually can be inefficient, laborious and prone to error. With the help of modern sensing technologies, high-throughput field phenotyping is becoming popular recently due to its ability of sensing various crop traits non-destructively with high efficiency. A multi-sensor phenotyping system equipped with red-green-blue (RGB) cameras, radiometers, ultrasonic sensors, spectrometers, a global positioning system (GPS) receiver, a pyranometer, a temperature and relative humidity probe and a light detection and ranging (LiDAR) …
Tailoring Cell-Material Interactions Via Poly(Acrylic Acid) Brushes
To Enhance Nonviral Substrate-Mediated Gene Delivery,
2019
University of Nebraska-Lincoln
Tailoring Cell-Material Interactions Via Poly(Acrylic Acid) Brushes To Enhance Nonviral Substrate-Mediated Gene Delivery, Amy Mantz
Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research
Nonviral gene delivery modifies gene expression by transferring exogenous genetic material into cells and tissues, typically through a bolus of complexes formed by electrostatic interactions between cationic lipid or polymer vectors with negatively charged nucleic acids (e.g. DNA). Although nonviral gene delivery is safer, more cost-effective, and more flexible compared to viral systems, nonviral transfection suffers from low efficiency due to extracellular and intracellular barriers. Much research has focused on tuning physiochemical properties of the complexing vectors to improve transfection, yet the cell-material interface may prove a better platform to immobilize DNA complexes for substrate-mediated delivery (SMD) and modulate the …
Microbial Transport As Affected By Residue Cover And Manure Application Rate,
2019
USDA, ARS, U.S. Meat Animal Research Center
Microbial Transport As Affected By Residue Cover And Manure Application Rate, Lisa M. Durso, John E. Gilley, Dave B. Marx, Chance A. Thayer, Brian L. Woodbury
Department of Agricultural and Biological Systems Engineering: Faculty Publications
Manure is applied to cropland areas with varying surface cover to meet single- or multiple-year crop nutrient requirements. The objectives of this field study were to (1) examine microbial transport following land application of manure to sites with and without wheat residue, (2) compare microbial loads following land application to meet the 0, 1, 2, 4, and 8-year P-based requirements for corn, and (3) evaluate the effects of rainfall simulation run on microbial transport. Manure was added and incorporated by disking plots that were 0.75 m wide by 2.0 m long. Three 30 min simulated rainfall events, separated by 24 …
