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Full-Text Articles in Environmental Engineering

Invasion Of The P Elements: Tolerance Is Not Futile, Colin D. Meiklejohn, Justin P. Blumenstiel Oct 2018

Invasion Of The P Elements: Tolerance Is Not Futile, Colin D. Meiklejohn, Justin P. Blumenstiel

Biological Systems Engineering: Papers and Publications

Organisms are locked in an eternal struggle with parasitic DNA sequences that live inside their genomes and wreak havoc on their host’s chromosomes as they spread through populations. To combat these parasites, host species have evolved elaborate mechanisms of resistance that suppress their activity. A new study in Drosophila indicates that, prior to the acquisition of resistance, individuals can vary in their ability to tolerate the activity of these genomic parasites, ignoring or repairing the damage they induce. This tolerance results from variation at genes involved in germline development and DNA damage checkpoints and suggests that these highly conserved cellular …


Cover Crops Have Negligible Impact On Soil Water In Nebraska Maize–Soybean Rotation, J. Burdette Barker, Derek M. Heeren, Katja Koehler-Cole, Charles Shapiro, Humberto Blanco-Canqui, Roger W. Elmore, Christopher A. Proctor, Suat Irmak, Charles A. Francis, Tim M. Shaver, Ali T. Mohammed Aug 2018

Cover Crops Have Negligible Impact On Soil Water In Nebraska Maize–Soybean Rotation, J. Burdette Barker, Derek M. Heeren, Katja Koehler-Cole, Charles Shapiro, Humberto Blanco-Canqui, Roger W. Elmore, Christopher A. Proctor, Suat Irmak, Charles A. Francis, Tim M. Shaver, Ali T. Mohammed

Biological Systems Engineering: Papers and Publications

One perceived cost of integrating winter cover cropping in maize (Zea mays L.) and soybean [Glycine max (L.) Merr.] rotation systems is the potential negative impact on soil water storage available for primary crop production. The objective of this 3-year study was to evaluate the effects of winter cover crops on soil water storage and cover crop biomass production following no-till maize and soybean rotations. Locations were near Brule (west-central), Clay Center (south-central), Concord (northeast), and Mead (east-central), Nebraska, United States. Treatments included crop residue only (no cover crop) and a multi-species cover crop mix, both broadcast-seeded before …


Portable Flux Tower Deployments Field Campaign Report, M. S. Torn, L Kuepper, S. C. Biraud, D. P. Billesbach Jun 2018

Portable Flux Tower Deployments Field Campaign Report, M. S. Torn, L Kuepper, S. C. Biraud, D. P. Billesbach

Biological Systems Engineering: Papers and Publications

Contents

Acronyms and Abbreviations...................................................................... iii

1.0 Summary ....................................................... 1

2.0 Results ........................................... 1

3.0 Publications and References ................................................. 2

4.0 Lessons Learned .................................................................... 2


Tradeoffs In Model Performance And Effort For Long-Term Phosphorus Leaching Based On In Situ Field Data, Ryan P. Freiberger, Derek M. Heeren, Dean E. Eisenhauer, Aaron R. Mittelstet, Guillermo Baigorria Jun 2018

Tradeoffs In Model Performance And Effort For Long-Term Phosphorus Leaching Based On In Situ Field Data, Ryan P. Freiberger, Derek M. Heeren, Dean E. Eisenhauer, Aaron R. Mittelstet, Guillermo Baigorria

Biological Systems Engineering: Papers and Publications

Phosphorus and N are critical nutrients for agriculture but are also responsible for surface water enrichment that leads to toxic algal growth. Although P loading to surface waters has traditionally been thought to occur primarily in surface runoff, contributions from subsurface transport can also be significant. The primary objectives of this research were to evaluate several methods of representing macropore flow and transport in a finite element model using plot-scale infiltration and leaching data and to compare several models of various levels of complexity to simulate long-term P leaching. To determine flow and transport parameters, single- and dual-porosity models in …


U.S. Agro-Climate In 20th Century: Growing Degree Days, First And Last Frost, Growing Season Length, And Impacts On Crop Yields, Meetpal Singh Kukal, Suat Irmak May 2018

U.S. Agro-Climate In 20th Century: Growing Degree Days, First And Last Frost, Growing Season Length, And Impacts On Crop Yields, Meetpal Singh Kukal, Suat Irmak

Biological Systems Engineering: Papers and Publications

Significant air temperature changes have occurred globally during the 20th century, which are spatially variable to a considerable degree and these changes can have substantial implications in agroecosystem productivity. The agroclimate indicators that are responsible in these contexts are first fall frost (FFF), last spring frost (LSF), climatological growing season (CGS) length, and heat accumulation (growing degree days, GDD). We explore spatial and temporal trends associated with these indices across the continental U.S. (CONUS) during 1900–2014 using datasets collected at 1218 sites. On average, FFF has been occurring later (by 5.4 days century−1), and LSF has been occurring …


Evaluation Of A Hybrid Reflectance-Based Crop Coefficient And Energy Balance Evapotranspiration Model For Irrigation Management, J. Burdette Barker, Christopher M. U. Neale, Derek M. Heeren, Andrew E. Suyker Apr 2018

Evaluation Of A Hybrid Reflectance-Based Crop Coefficient And Energy Balance Evapotranspiration Model For Irrigation Management, J. Burdette Barker, Christopher M. U. Neale, Derek M. Heeren, Andrew E. Suyker

Biological Systems Engineering: Papers and Publications

Accurate generation of spatial soil water maps is useful for many types of irrigation management. A hybrid remote sensing evapotranspiration (ET) model combining reflectance-based basal crop coefficients (Kcbrf) and a two-source energy balance (TSEB) model was modified and validated for use in real-time irrigation management. We modeled spatial ET for maize and soybean fields in eastern Nebraska for the 2011-2013 growing seasons. We used Landsat 5, 7, and 8 imagery as remote sensing inputs. In the TSEB, we used the Priestly-Taylor (PT) approximation for canopy latent heat flux, as in the original model formulations. We also used the …


Climate-Driven Crop Yield And Yield Variability And Climate Change Impacts On The U.S. Great Plains Agricultural Production, Meetpal Singh Kukal, Suat Irmak Feb 2018

Climate-Driven Crop Yield And Yield Variability And Climate Change Impacts On The U.S. Great Plains Agricultural Production, Meetpal Singh Kukal, Suat Irmak

Biological Systems Engineering: Papers and Publications

Climate variability and trends affect global crop yields and are characterized as highly dependent on location, crop type, and irrigation. U.S. Great Plains, due to its significance in national food production, evident climate variability, and extensive irrigation is an ideal region of investigation for climate impacts on food production. This paper evaluates climate impacts on maize, sorghum, and soybean yields and effect of irrigation for individual counties in this region by employing extensive crop yield and climate datasets from 1968–2013. Variability in crop yields was a quarter of the regional average yields, with a quarter of this variability explained by …


Dynamic Rops Test For Tractors Over 6,000 Kilograms, Caleb M. Lindhorst, Roger M. Hoy, Santosh Pitla, Michael F. Kocher Jan 2018

Dynamic Rops Test For Tractors Over 6,000 Kilograms, Caleb M. Lindhorst, Roger M. Hoy, Santosh Pitla, Michael F. Kocher

Biological Systems Engineering: Papers and Publications

OECD static tests (Codes 4, 6, 7, and 8) for agricultural rollover protective structures (ROPS) have become accepted standards for evaluating the ability of these structures to protect the operator during tractor rollover events. The strength properties of some materials typically used in ROPS change because of cold weather embrittlement at low temperatures. The static ROPS tests lack the ability to evaluate the strength of these structures during cold weather. The use of the dynamic ROPS test is well noted as a means for proving cold weather embrittlement resistance properties. Unfortunately, application of the OECD dynamic ROPS test (Code 3) …


Field-Based Scoring Of Soybean Iron Deficiency Chlorosis Using Rgb Imaging And Statistical Learning, Geng Bai, Shawn Jenkins, Wenan Yuan, George L. Graef, Yufeng Ge Jan 2018

Field-Based Scoring Of Soybean Iron Deficiency Chlorosis Using Rgb Imaging And Statistical Learning, Geng Bai, Shawn Jenkins, Wenan Yuan, George L. Graef, Yufeng Ge

Biological Systems Engineering: Papers and Publications

Iron deficiency chlorosis (IDC) is an abiotic stress in soybean that can cause significant biomass and yield reduction. IDC is characterized by stunted growth and yellowing and interveinal chlorosis of early trifoliate leaves. Scoring IDC severity in the field is conventionally done by visual assessment. The goal of this study was to investigate the usefulness of Red Green Blue (RGB) images of soybean plots captured under the field condition for IDC scoring. A total of 64 soybean lines with four replicates were planted in 6 fields over 2 years. Visual scoring (referred to as Field Score, or FS) was conducted …


Crop Evapotranspiration, Irrigationwater Requirement And Water Productivity Of Maize From Meteorological Data Under Semiarid Climate, Koffi Djaman, Michael O'Neill, Curtis K. Owen, Daniel Smeal, Komlan Koudahe, Margaret West, Samuel Allen, Kevin Lombard, Suat Irmak Jan 2018

Crop Evapotranspiration, Irrigationwater Requirement And Water Productivity Of Maize From Meteorological Data Under Semiarid Climate, Koffi Djaman, Michael O'Neill, Curtis K. Owen, Daniel Smeal, Komlan Koudahe, Margaret West, Samuel Allen, Kevin Lombard, Suat Irmak

Biological Systems Engineering: Papers and Publications

Under the semiarid climate of the Southwest United States, accurate estimation of crop water use is important for water management and planning under conservation agriculture. The objectives of this study were to estimate maize water use and water productivity in the Four Corners region of New Mexico. Maize was grown under full irrigation during the 2011, 2012, 2013, 2014 and 2017 seasons at the Agricultural Science Center at Farmington (NM). Seasonal amounts of applied irrigation varied from 576.6 to 1051.6 mm and averaged 837.7 mm and the total water supply varied from 693.4 to 1140.5 mm. Maize actual evapotranspiration was …


Unmanned Aerial Systems-Based Remote Sensing For Monitoring Sorghum Growth And Development, Sanaz Shafian, Nithya Rajan, Ronnie Schnell, Muthukumar Bagavathiannan, John Valasek, Yeyin Shi, Jeff Olsenholler Jan 2018

Unmanned Aerial Systems-Based Remote Sensing For Monitoring Sorghum Growth And Development, Sanaz Shafian, Nithya Rajan, Ronnie Schnell, Muthukumar Bagavathiannan, John Valasek, Yeyin Shi, Jeff Olsenholler

Biological Systems Engineering: Papers and Publications

Unmanned Aerial Vehicles and Systems (UAV or UAS) have become increasingly popular in recent years for agricultural research applications. UAS are capable of acquiring images with high spatial and temporal resolutions that are ideal for applications in agriculture. The objective of this study was to evaluate the performance of a UAS-based remote sensing system for quantification of crop growth parameters of sorghum (Sorghum bicolor L.) including leaf area index (LAI), fractional vegetation cover (fc) and yield. The study was conducted at the Texas A&M Research Farm near College Station, Texas, United States. A fixed-wing UAS equipped with a …


Hydrologic Evaluation Of Residential Rain Gardens Using A Stormwater Runoff Simulator, A. R. Anderson, T. G. Franti, D. P. Shelton Jan 2018

Hydrologic Evaluation Of Residential Rain Gardens Using A Stormwater Runoff Simulator, A. R. Anderson, T. G. Franti, D. P. Shelton

Biological Systems Engineering: Papers and Publications

Engineered bioretention cells with underdrains have shown water quality and hydrologic benefits for abating urban stormwater problems. Less is known about the hydrologic performance of residential rain gardens that rely on in situ soil infiltration as the primary mechanism of volume control. Eleven residential rain gardens in Lincoln, Nebraska, were evaluated using a variable-rate stormwater runoff simulator. A volume-based water quality volume (WQV) design storm of 3.0 cm was applied to each rain garden as an SCS Type II runoff hydrograph until the system began overflowing to test the rain gardens for surface and subsurface storage capacity, drawdown rate, ponding …


Evaluation Of Critical Nitrogen And Phosphorus Models For Maize Under Full And Limited Irrigation Conditions, Koffi Djaman, Suat Irmak Jan 2018

Evaluation Of Critical Nitrogen And Phosphorus Models For Maize Under Full And Limited Irrigation Conditions, Koffi Djaman, Suat Irmak

Biological Systems Engineering: Papers and Publications

Proper nitrogen (N) fertiliser application rates and timing of application, coupled with optimum irrigation management can improve the sustainability of maize production and reduce the risk of environmental contamination by nutrients. The impact of full and limited irrigation and rainfed conditions on in-season maize (Zea mays L.) shoot biomass nutrient concentration and critical N and phosphorus (P) indices were evaluated using a combination of measured nutrients and critical N and P models in south central Nebraska in 2009 and 2010. Four irrigation treatments [fully-irrigated treatment (FIT), 75% FIT, 60% FIT and 50% FIT) and rainfed] were imposed. Irrigation regimes …


Impact Of Vegetative Treatment Systems On Multiple Measures Of Antibiotic Resistance In Agricultural Wastewater, Lisa M. Durso, Daniel N. Miller, Christopher G. Henry Jan 2018

Impact Of Vegetative Treatment Systems On Multiple Measures Of Antibiotic Resistance In Agricultural Wastewater, Lisa M. Durso, Daniel N. Miller, Christopher G. Henry

Biological Systems Engineering: Papers and Publications

Wastewater is an important vector of antibiotic resistant bacteria and antibiotic resistance genes (ARB/G). While there is broad agreement that ARB/G from agricultural (ag) wastewaters can be transported through the environment and may contribute to untreatable infectious disease in humans and animals, there remain large knowledge gaps surrounding applied details on the types and amounts of ARB/G associated with different agricultural wastewater treatment options and different ag production systems. This study evaluates a vegetative treatment system (VTS) built to treat the wastewater from a beef cattle feedlot. Samples were collected for three years, and plated on multiple media types to …


Special Issue: Microbial Community Modeling: Prediction Of Microbial Interactions And Community Dynamics, Hyun-Seob Song Jan 2018

Special Issue: Microbial Community Modeling: Prediction Of Microbial Interactions And Community Dynamics, Hyun-Seob Song

Biological Systems Engineering: Papers and Publications

Microbial communities are networks of species, the interaction structure of which dynamically reorganizes in a varying environment. Even in a static condition, community dynamics are often difficult to predict due to highly nonlinear interspecies interactions. Understanding the fundamental principles of microbial interactions is therefore key for predicting and harnessing community function and properties. As extensively reviewed previously, mathematical models and computational methods that can predictively link interactions to community behaviors are indispensable tools for achieving this goal [1].


Comparison Of Three Regionalization Techniques For Predicting Streamflow In Ungaged Watersheds In Nebraska, Usa Using Swat Model, Michael W. Van Liew, Aaron R. Mittelstet Jan 2018

Comparison Of Three Regionalization Techniques For Predicting Streamflow In Ungaged Watersheds In Nebraska, Usa Using Swat Model, Michael W. Van Liew, Aaron R. Mittelstet

Biological Systems Engineering: Papers and Publications

This study compared three approaches, regional averaging, nearest neighbor, and donor techniques, to regionalize parameters in the Soil and Water Assessment Tool (SWAT) on eleven watersheds located in the Dissected Plains, Plains, and Rolling Hills Landforms in the eastern portion of the State of Nebraska, USA. Within the Rolling Hills Landform, three watersheds were randomly selected as calibration watersheds while two were randomly selected as validation watersheds. Two watersheds were randomly selected as calibration watersheds while one was randomly selected as a validation watershed within each of the Dissected Plains and Plains Landforms. The seven calibration watersheds were used to …


Impact Of Eastern Redcedar Proliferation On Water Resources In The Great Plains Usa—Current State Of Knowledge, Chris B. Zou, Dirac Twidwell, Christine H. Bielski, Dillon T. Fogarty, Aaron R. Mittelstet, Patrick J. Starks, Rodney E. Will, Yu Zhong, Bharat Sharma Acharya Jan 2018

Impact Of Eastern Redcedar Proliferation On Water Resources In The Great Plains Usa—Current State Of Knowledge, Chris B. Zou, Dirac Twidwell, Christine H. Bielski, Dillon T. Fogarty, Aaron R. Mittelstet, Patrick J. Starks, Rodney E. Will, Yu Zhong, Bharat Sharma Acharya

Biological Systems Engineering: Papers and Publications

In the Great Plains of the central United States, water resources for human and aquatic life rely primarily on surface runoff and local recharge from rangelands that are under rapid transformation to woodland by the encroachment of Eastern redcedar (redcedar; Juniperus virginiana) trees. In this synthesis, the current understanding and impact of redcedar encroachment on the water budget and water resources available for non-ecosystem use are reviewed. Existing studies concluded that the conversion from herbaceous-dominated rangeland to redcedar woodland increases precipitation loss to canopy interception and vegetation transpiration. The decrease of soil moisture, particularly for the subsurface soil layer, …


Integration Of Hydrogeophysical Datasets And Empirical Orthogonal Functions For Improved Irrigation Water Management, Catherine E. Finkenbiner, Trenton E. Franz, Justin P. Gibson, Derek M. Heeren, J. D. Luck Jan 2018

Integration Of Hydrogeophysical Datasets And Empirical Orthogonal Functions For Improved Irrigation Water Management, Catherine E. Finkenbiner, Trenton E. Franz, Justin P. Gibson, Derek M. Heeren, J. D. Luck

Biological Systems Engineering: Papers and Publications

Precision agriculture offers the technologies to manage for infield variability and incorporate variability into irrigation management decisions. The major limitation of this technology often lies in the reconciliation of disparate data sources and the generation of irrigation prescription maps. Here the authors explore the utility of the cosmic-ray neutron probe (CRNP) which measures volumetric soil water content (SWC) in the top ~ 30 cm of the soil profile. The key advantages of CRNP is that the sensor is passive, non-invasive, mobile and soil temperature-invariant, making data collection more compatible with existing farm operations and extending the mapping period. The objectives …


Phenotypic Responses To Interspecies Competition And Commensalism In A Naturally Derived Microbial Co-Culture, Nymul Khan, Yukari Maezato, Ryan S. Mcclure, Colin J. Brislawn, Jennifer M. Mobberley, Nancy Isern, William B. Chrisler, Lye Meng Markillie, Brett M. Barney, Hyun-Seob Song, William C. Nelson, Hans C. Bernstein Jan 2018

Phenotypic Responses To Interspecies Competition And Commensalism In A Naturally Derived Microbial Co-Culture, Nymul Khan, Yukari Maezato, Ryan S. Mcclure, Colin J. Brislawn, Jennifer M. Mobberley, Nancy Isern, William B. Chrisler, Lye Meng Markillie, Brett M. Barney, Hyun-Seob Song, William C. Nelson, Hans C. Bernstein

Biological Systems Engineering: Papers and Publications

The fundamental question of whether different microbial species will co-exist or compete in a given environment depends on context, composition and environmental constraints. Model microbial systems can yield some general principles related to this question. In this study we employed a naturally occurring co-culture composed of heterotrophic bacteria, Halomonas sp. HL-48 and Marinobacter sp. HL- 58, to ask two fundamental scientific questions: 1) how do the phenotypes of two naturally co-existing species respond to partnership as compared to axenic growth? and 2) how do growth and molecular phenotypes of these species change with respect to competitive and commensal interactions? We …


Surface Detention On Cropland, Rangeland, And Conservation Reserve Program Areas, John E. Gilley Jan 2018

Surface Detention On Cropland, Rangeland, And Conservation Reserve Program Areas, John E. Gilley

Biological Systems Engineering: Papers and Publications

One of the factors contributing to overland flow on upland areas is water stored temporarily in a thin sheet on the soil surface as surface detention. This study was conducted to quantify surface detention on selected cropland, rangeland, and Conservation Reserve Program (CRP) sites. Surface detention was determined from the recession portion of runoff hydrographs corresponding with the period when rainfall had ceased but runoff continued. The hydrographs were generated from six previously reported rainfall simulation studies conducted on paired 3.7 m wide  10.7 m long plots on which approximately 128 mm of rainfall was applied. Surface detention values …


Evaluation Of The Accuracy Of Machine Reported Can Data For Engine Torque And Speed (J1939), Rodney A. Rohrer, Joe D. Luck, Santosh K. Pitla, Roger M. Hoy Jan 2018

Evaluation Of The Accuracy Of Machine Reported Can Data For Engine Torque And Speed (J1939), Rodney A. Rohrer, Joe D. Luck, Santosh K. Pitla, Roger M. Hoy

Biological Systems Engineering: Papers and Publications

Most modern off-road machinery use embedded electronic controllers connected to a controller area network (CAN) to broadcast machine information for on-board processes and diagnostics. Commercially available tools can record CAN data for a variety of research and commercial uses. For agricultural tractors, there is an opportunity to create advanced test procedures that are more representative of field operations and that could supplement existing machine performance tests, such as the OECD Code 2 Standard Code for the Official Testing of Agricultural and Forestry Tractor Performance. CAN parameters provide an efficient way to collect tractor performance data during field operations. However, the …


Near Infrared Fluorescent Single Walled Carbon Nanotubes As Tissue Localizable Biosensors, Nicole M. Iverson, Michael S. Strano, Nigel F. Strano, Thomas P. Mcnicholas Jan 2018

Near Infrared Fluorescent Single Walled Carbon Nanotubes As Tissue Localizable Biosensors, Nicole M. Iverson, Michael S. Strano, Nigel F. Strano, Thomas P. Mcnicholas

Biological Systems Engineering: Papers and Publications

A nanosensor for detecting an analyte can include a sub strate, a photoluminescent nanostructure, and a polymer interacting with the photoluminescent nanostructure. The nanosensor can be used in in vivo for biomedical applications.


Nitric Oxide Sensors For Biological Applications, Nicole M. Iverson, Eric M. Hofferber, Joseph A. Stapleton Jan 2018

Nitric Oxide Sensors For Biological Applications, Nicole M. Iverson, Eric M. Hofferber, Joseph A. Stapleton

Biological Systems Engineering: Papers and Publications

Nitric oxide (NO) is an essential signaling molecule within biological systems and is believed to be involved in numerous diseases. As a result of NO’s high reaction rate, the detection of the concentration of NO, let alone the presence or absence of the molecule, is extremely difficult. Researchers have developed multiple assays and probes in an attempt to quantify NO within biological solutions, each of which has advantages and disadvantages. This review highlights many of the current NO sensors, from those that are commercially available to the newest sensors being optimized in research labs, to assist in the understanding and …


Effects Of Subsurface Drainage Systems On Water And Nitrogen Footprints Simulated With Rzwqm2, Kristina J. Craft, Matthew J. Helmers, Robert W. Malone, Carl H. Pederson, Linda R. Schott Jan 2018

Effects Of Subsurface Drainage Systems On Water And Nitrogen Footprints Simulated With Rzwqm2, Kristina J. Craft, Matthew J. Helmers, Robert W. Malone, Carl H. Pederson, Linda R. Schott

Biological Systems Engineering: Papers and Publications

Developing drainage water management (DWM) systems in the Midwest to reduce nitrogen (N) transport to the northern Gulf of Mexico hypoxic zone requires understanding of the long-term performance of these systems. Few studies have evaluated long-term impacts of DWM, and the simulation of controlled drainage (CD) with the Root Zone Water Quality Model (RZWQM) is limited, while shallow drainage (SD) has not been examined. We tested RZWQM using nine years (2007-2015) of field data from southeast Iowa for CD, SD, conventional drainage (DD), and undrained (ND) systems and simulated the long-term (1971-2015) impacts. RZWQM accurately simulated N loss in subsurface …


Prediction Of Agricultural Implement Hydraulic Power Requirements Using Controller Area Network Bus Data, Gabriel P. Stoll, Rodney A. Rohrer, Santosh K. Pitla, Joe D. Luck Jan 2018

Prediction Of Agricultural Implement Hydraulic Power Requirements Using Controller Area Network Bus Data, Gabriel P. Stoll, Rodney A. Rohrer, Santosh K. Pitla, Joe D. Luck

Biological Systems Engineering: Papers and Publications

One of the important challenges in agricultural machinery research is the ability to effectively determine power requirements of a given field operation. The Controller Area Network (CAN) Bus, also known as ISOBUS, has proven to be an effective digital tool for tractor and implement data collection. This study attempted to determine implement hydraulic power requirements using a combination of existing public tractor CAN messages and minimal added sensors. The sensor signals were published on the CAN bus for ease of simultaneous sensor signal and CAN message data collection. Based upon the available CAN messages, this study attempted to measure hydraulic …


Effects Of Alternate Wetting And Drying Irrigation Regime And Nitrogen Fertilizer On Yield And Nitrogen Use Efficiency Of Irrigated Rice In The Sahel, Koffi Djaman, Valere C. Mel, Lamine Diop, Abdoulaye Sow, Raafat El-Namaky, Baboucarr Manneh, Kazuki Saito, Koichi Futakuchi, Suat Irmak Jan 2018

Effects Of Alternate Wetting And Drying Irrigation Regime And Nitrogen Fertilizer On Yield And Nitrogen Use Efficiency Of Irrigated Rice In The Sahel, Koffi Djaman, Valere C. Mel, Lamine Diop, Abdoulaye Sow, Raafat El-Namaky, Baboucarr Manneh, Kazuki Saito, Koichi Futakuchi, Suat Irmak

Biological Systems Engineering: Papers and Publications

The objectives of this study were to investigate water saving strategies in the paddy field and to evaluate the performance of some of the newly released rice varieties. Field experiments were conducted at Fanaye in the Senegal River Valley during two rice growing seasons in 2015. Three irrigation regimes ((i) continuous flooding, (ii) trigging irrigation at soil matric potential (SMP) of 30 kPa, (iii) trigging irrigation at SMP of 60 kPa) were tested in an irrigated lowland rice field. Irrigation regimes (ii) and (iii) are alternate wetting and drying (AWD) cycles. Four inbred rice varieties (NERICA S-21, NERICA S-44, Sahel …


Registration For Optical Multimodal Remote Sensing Images Based On Fast Detection,Window Selection, And Histogram Specification, Xiaoyang Zhao, Jian Zhang, Chenghai Yang, Huaibo Song, Yeyin Shi, Xingen Zhou, Dongyan Zhang, Guozhong Zhang Jan 2018

Registration For Optical Multimodal Remote Sensing Images Based On Fast Detection,Window Selection, And Histogram Specification, Xiaoyang Zhao, Jian Zhang, Chenghai Yang, Huaibo Song, Yeyin Shi, Xingen Zhou, Dongyan Zhang, Guozhong Zhang

Biological Systems Engineering: Papers and Publications

In recent years, digital frame cameras have been increasingly used for remote sensing applications. However, it is always a challenge to align or register images captured with different cameras or different imaging sensor units. In this research, a novel registration method was proposed. Coarse registration was first applied to approximately align the sensed and reference images. Window selection was then used to reduce the search space and a histogram specification was applied to optimize the grayscale similarity between the images. After comparisons with other commonly-used detectors, the fast corner detector, FAST (Features from Accelerated Segment Test), was selected to extract …


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 Jan 2018

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 …


Investigation Of Organic Solvents’ Effects On Kenaf (Hibiscus Cannabinus L.) Biomass Conversion In Subcritical Water, Bahar Meryemoglu, Arif Hasanoglu, Mehtap Kurtulus, Sibel Irmak Jan 2018

Investigation Of Organic Solvents’ Effects On Kenaf (Hibiscus Cannabinus L.) Biomass Conversion In Subcritical Water, Bahar Meryemoglu, Arif Hasanoglu, Mehtap Kurtulus, Sibel Irmak

Biological Systems Engineering: Papers and Publications

Kenaf biomass was hydrolyzed under subcritical water conditions in the presence of various organic solvents. The solvents tested were tetrahydrofuran (THF), acetone, xylene (mixed isomers) and methanol. The organic compounds released into hydrolysates, total organic contents, water-soluble total phenols, and the molecular weight distributions of the polysaccharides in the hydrolysates, solid residues leftover after hydrolysis and gaseous products formed during the solubilization process were determined. The results showed that organic solvents significantly enhanced the dissolution of kenaf biomass (methanol < (omp)xylene ≤ acetone ~ tetrahydrofuran). The hydrolysis percentage was found to be between 75-82% depending on the type of the solvent. Hydrolysis yield and total organic carbons released into hydrolysates highly differed when the solubilization process was performed under carbon dioxide pressure and this effect considerably varied based on the type of solvent used in hydrolysis process. The main gas product formed during hydrolysis process was carbon dioxide with ~80% composition. Morphological measurements of the solid biomass residues left after hydrolysis showed substantial degradations with increasing number of pores on the biomass surfaces.


A Tunable, Three-Dimensional In Vitro Culture Model Of Growth Plate Cartilage Using Alginate Hydrogel Scaffolds, Alek G. Erickson, Taylor D. Laughlin, Sarah M. Romereim, Catherine N. Sargus-Patino, Angela K. Pannier, Andrew T. Dudley Jan 2018

A Tunable, Three-Dimensional In Vitro Culture Model Of Growth Plate Cartilage Using Alginate Hydrogel Scaffolds, Alek G. Erickson, Taylor D. Laughlin, Sarah M. Romereim, Catherine N. Sargus-Patino, Angela K. Pannier, Andrew T. Dudley

Biological Systems Engineering: Papers and Publications

Defining the final size and geometry of engineered tissues through precise control of the scalar and vector components of tissue growth is a necessary benchmark for regenerative medicine, but it has proved to be a significant challenge for tissue engineers. The growth plate cartilage that promotes elongation of the long bones is a good model system for studying morphogenetic mechanisms because cartilage is composed of a single cell type, the chondrocyte; chondrocytes are readily maintained in culture; and growth trajectory is predominately in a single vector. In this cartilage, growth is generated via a differentiation program that is spatially and …