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| Filter results23 paper(s) found. |
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1. Development And Evaluation Of A Leaf Monitoring System For Continuous Measurement Of Plant Water Status In Almond And Walnut CropsAbstract: Leaf temperature measurements using handheld infrared thermometers have been used to predict plant water stress by calculating crop water stress index (CWSI). However, for CWSI calculations it is recommended to measure canopy temperature of trees under saturated, stressed and current conditions simultaneously, which is not very practical while using handheld units. An inexpensive, easy to use sensing system was developed to predict plant water status for tree crops by ... F. Rojo, J. Roach, R. Coates, S. Upadhyaya, M. Delwiche, C. Han, R. Dhillon |
2. Soil Mapping And Modeling On Twenty-Five Ingredients Using A Real-Time Soil SensorVisible and near-infrared spectroscopy is an effective measurement method for estimating many soil ingredients at once. In precision agriculture, rapid, non-destructive, cost-effective and convenient soil analysis techniques are needed for soil management, crop quality control using fertilizer, manure and compost, and variable-rate input for soil variability in a field. We obtained Twenty-five calibration models based on Vis-NIR (305 - 1700 nm) underground soil ... M. Kodaira, S. Shibusawa |
3. Suitability Of Crop Canopy Sensors For Determining Irrigation Differences In MaizeWater is the most limiting factor for agricultural production in the semiarid environment of the western Great Plains of the United States. Dry climate conditions combined with a large availability of ground water has led to crop systems that are dependent on irrigation for maximum yields. An increased emphasis on water is forcing users to find new ways to increase the efficiency of water used for agriculture. Crop canopy sensors may have the potential to deter... G. Kruger, S. Van donk, T.M. Shaver |
4. Visible And Near-Infrared Spectroscopy For Monitoring Potentially Toxic Elements In Reclaimed Dumpsite Soils Of The Czech RepublicDue to rapid economic development, high levels of potentially harmful elements and heavy metals are continuously being released into the brown coal mining dumpsites of the Czech Republic. Elevated metal contents in soils not only dramatically impact the soil quality, but also due to their persistent nature and long biological half-lives, contaminant elements can accumulate in the food chain and can eventually endanger human health. Conventional methods for investigating potentia... L. Borùvka, M. Saberioon, R. Vašát, A. Gholizadeh |
5. Evaluation Of The Temporal And Operational Stability Of Apparent Soil Electrical Conductivity MeasurementsMeasuring apparent soil electrical conductivity (ECa), using galvanic contact resistivity (GCR) and electromagnetic induction (EMI) techniques is frequently used to implement site-specific crop management. Various research projects have demonstrated the possibilities for significant changes in the measured quantities over time with relatively stable spatial structure representations. The objective of this study was to quantify the effects of temporal drift and operational noise for three... V.I. Adamchuk, A. Mat su |
6. Development Of An On-The-Spot Analyzer For Measuring Soil Chemical PropertiesProximal soil sensing (PSS) is a growing area of research and development focusing on the use of sensors to obtain information on the physical, chemical and biological attributes of soil when they are placed in contact with, or at a distance of less than 2 m, from the target. These sensor systems have been used to 1) make measurements at specific locations, 2) produce a set of measurements related to soil depth profiles, or 3) monitor changes in soil properties over time. In eac... V.I. Adamchuk, N. Dhawale, F. Rene-laforest |
7. Measuring And Mapping Sugarcane GapsSugarcane is an important crop in tropical regions of the world and especially for Brazil, the largest sugar supplier in the market, also running a domestic fleet of flex-fuel driven vehicles based on ethanol. Site specific production management can impact sugarcane production by increasing yield and reducing cost. Sugarcane fields are planted each five years, in average, and an important parameter that is measured after the planting operation is the gaps caused by problems during planti... J.P. Veiga, D.S. Cavalcante, J.P. Molin |
8. Development Of Online Soil Profile Sensor For Variable Depth TillageIntroduction First introduced in the early 1990s, precision agriculture technologies, or site-specific management, were considered by many to be perhaps the most significant development in production agriculture focused on improving farm profitability. The initial focus was on fertility, and treating the variability that we all knew existed from our experiences with soil sampling. However, to a large extent this application stil... A.B. Tekin, H. Yalcin |
9. 3-Dimension Reconstruction Of Cactus Using Multispectral ImagesUsing 3D reconstruction result to investigate plant morphology has been a focus of virtual plant. And multispectral imaging has proved to carried biological information in quite a lot work. This paper present a idea to investigate chlorophyll spatial variability of cactus using a bunch of multispectral images. 46 multispectral images are taken at equally distributed angles surrounding the tree and have over 80% overlap. Structure from motion approach has been u... F. Liu, Y. He, Y. Zhang, L. Tan, Y. Zhang, L. Jiang |
10. A Method For Sampling Scab Spots On Apple Leaves In The Orchard Using Machine VisionIntroduction One of the largest threats in apple orchards is scab. Current procedures involve models based on weather data that predict the likelihood of scab attacks. In case of alarm the orchard is sprayed with preventive pesticides and this typically happens 25-30 times per season. The scab attacks the leaves and stays on fallen leaves that reinfect the trees with rainwater, making it an advantage to include a-priori knowledge on previous... M.G. Bertelsen, K. Nielsen, M.R. Nielsen |
11. Using A Potable Spectroradiometer For In-Situ Measurement Of Soil Properties In A Slope Citrus FieldIn precision agriculture, rapid, non-destructive, cost-effective and convenient soil analysis techniques are needed for crop and soil management. However, the spatial variability of soil properties is consider to be high cost and time consuming to characterize using traditional soil analysis method. To achieve cost and time reduction, the potential benefits of in-situ measurement of soil spectra have been recognized. ... S. Shibusawa, H. Umeda, K. Usui, M. Kodaira, Q. Li |
12. Rapid Sensing For Water Stress Detection In Foxtail Millet (Setaria Italica)In recent years, the drought conditions due to changing climate patterns have adversely affected the U.S. agriculture. The 2012 drought that damaged major crops in Midwest was one of the most severe in last 25 years. It has resulted in losses of production, revenue, livestock and jobs, and has increased food prices. Under these circumstances, farmers are focused to use the water resources carefully. The researchers are working together to develop new crop varieties resistant to ... S. Sankaran, M. Wang, P. Ellsworth, A. Cousins |
13. Field-Based High-Throughput Phenotyping Approach For Soybean Plant ImprovementThe continued development of new, high yielding cultivars needed to meet the world’s growing food demands will be aided by improving the technology to rapidly phenotype potential cultivars. High-throughput phenotyping (HTP) is essential to maximize the greatest value of genetics analysis and to better understand the plant biology and physiology in view of a “Feed the World in 2050” theme. Field-based high-throughput&nb... L. Li, D. Jiang, R.P. Campos, Z. Lu, L.F. Tian |
14. Multivariate Geostatistics As A Tool To Estimate Physical And Chemical Soil Properties With Reduced Sampling In Area Planted With SugarcanePrecision Agriculture (PA) can be described as a set of tools and techniques applied to agriculture in order to enable localized production management, considering the spatial and temporal variability of crop fields. Among the numerous existing tools, one of the most important ones is the use of geostatistics, whose main objective is the description of spatial patterns and estimation data in non-sampled places. Nowadays, one of the most limiting factors to t... G.M. Sanches, P.S. Graziano magalhaes, H.C. Franco, A.Z. Remacre |
15. Evaluating Leaf Fluorescence Sensor Dualex 4 For Estimating Rice Nitrogen Status In Northeast ChinaReal-time non-destructive diagnosis of crop nitrogen (N) status is crucially important for the success of in-season site-specific N management. Chlorophyll meter (CM) has been commonly used to non-destructively estimate crop leaf chlorophyll concentration, and indirectly estimate crop N status. Dualex 4 is a newly developed leaf fluorescence sensor that can estimate both leaf chlorophyll concentration and polyphenolics, especially flavonoids. When N is deficient, N stress can in... W. Yu, Y. Miao, S. Hu, J. Shen, H. Wang |
16. Selection Of Fluorescence Indices For The Proximal Sensing Of Single And Multiple Stresses In Sugar BeetThe use of fluorescence indices for sensing the impact of abiotic and biotic stresses in agricultural crops is well documented in the literature. Pigment fluorescence gives a precise picture about the plant physiology and its changes following the occurrence of stresses. In general, alterations in such optical signals is caused either by the stress-induced accumulation of one or more fluorophores, or the degradation of specific molecules like chlorophyll. Unfortunately, many str... G. Leufen, G. Noga, M. Hunsche |
17. Use Of Active Radiometers To Estimate Biomass, Leaf Area Index, And Plant Height In CottonActive radiometers have been tested extensively as tools to assess in-season nitrogen (N) status of crops like wheat (Triticum aestivum), corn (Zea mays), and cotton (Gossypium hirsutum). Fewer studies target in-season plant growth parameters such as biomass, plant height or leaf area index (LAI). Uses of this plant data include simulation modeling, total N uptake measurements, evapotranspiration (ET) estimates and irrigati... K.R. Thorp, J.W. White, M.M. Conley, J. Mon, K.F. Bronson |
18. Prediction Of Cation Exchange Capacity Using Visible And Near Infrared SpectroscopyCation exchange capacity (CEC) of the soil is a measure of the soil ability to hold positively charged ions and is an important indicator of soil physicochemical characteristic. It is an important property for site specific management of soil nutrients in precision agriculture. The conventional analytical methods used for the determination of CEC are expensive, difficult and time consuming, because different cations must be extracted and determined. Visible and near infrared (vis-NIR) sp... Y. Ulusoy, Z. Tümsavas, A.M. Mouazen, Y. Tekin |
19. Hand-Held Sensor For Measuring Crop Reflectance And Assessing Crop Biophysical CharacteristicsCrop vigor is difficult enough to define, let alone characterize and conveniently quantify. The human eye is particularly sensitive to green light, but quantifying subtle differences in plant greenness is subjective and therefore problematic in terms of making definitive management decisions. Plant greenness is one component of crop vigor and leaf area index or the relative ability o... J.S. Schepers, K.H. Holland |
20. Airborne Active Optical Sensors (AOS) For Photosynthetically-Active Biomass Sensing: Current Status And Future OpportunitiesThe first published deployment of an active optical reflectance sensor (AOS) in a low-flying aircraft in 2009 catalyzed numerous developments in both sensor development and sensor platform integration. Integral to these sensors is a modulated light source composed of high power LED technology that emits high radiance polychromatic light. The sensor easily mounts to agricultural aircraft and can sense agricultural landscapes at altitudes from a few meters to altitudes exceeding 40 meters ... K.H. Holland, D.W. Lamb |
21. Evaluating Spatial Effects Induced by Alternative On- Farm Trial Experimental Designs with Cross-regressive Variables Using Monte Carlo MethodsThe goal of this research was to adapt spatial regression methods to on-farm trials in a farm management context. Different experimental designs and statistical analysis methods are tested with site-specific data under a range of spatial autocorrelation levels using Monte Carlo simulation techniques. Simulations indicated that data usable for farm management decision making could be gathered from limited replication experimental designs if that data were analyzed with the appropriate spatial ... T.W. Griffin, R.J. G.m. florax, J. Lowenberg-deboer |
22. A New Approach for Quantitative Land Suitability Evaluation Using Geostatistics, Remote Sensing (Rs) and Geographic Information System (Gis)The objective of this study was to incorporate geostatistics, remote sensing and geographic information system methods due to improving the quantitative land suitability assessment in Arsanjan plain, southern Iran. The primary data was collected from 85 soil samples from tree depths (030, 3060 and 6090 cm) and the secondary information from remotely sensed data “LISSIII receiver from IRSP6 satellite”. In order to identify the spatial dependence of soil imp... M. Baghernejad, M. Emadi |
23. Use of a Cropping System Model for Soil-specific Optimization of Limited WaterIn the arena of modern agriculture, system models capable of simulating the complex interactions of all the relevant processes in the soil-water-plant- atmosphere continuum are widely accepted as potential tools for decision support to optimize crop inputs of water to achieve location specific yield potential while minimizing environmental (soil and water resources) impacts. In a recent study, we calibrated, validated, and applied the CERES-Maize v4.0 model for simulating limited-water irriga... L.R. Ahuja, S.A. Saseendran, L. Ma, D.C. Nielsen, T.J. Trout, A.A. Andales, N.C. Hansen |