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The impact of sensor characteristics for obtaining accurate ground-based measurements of LAI

William Woodgate, Mathias Disney, John Armston, Simon Jones, Lola Suarez, Michael Hill, Phillip Wilkes, Mariela Soto-Berelov, Andrew Haywood, Andrew Mellor
2013 2013 IEEE International Geoscience and Remote Sensing Symposium - IGARSS  
Calibration and validation of LAI products require accurate ground-based measurements.  ...  However these sensors have biases in regards to the true LAI value, which can never be known in the field.  ...  ) between instruments for deriving accurate ground-based measurements of LAI.  ... 
doi:10.1109/igarss.2013.6723226 dblp:conf/igarss/WoodgateDAJSHWSHM13 fatcat:fo2ivl6gizbyhafklqqabnb5ey

Advanced Technologies for the Improvement of Spray Application Techniques in Spanish Viticulture: An Overview

Emilio Gil, Jaume Arnó, Jordi Llorens, Ricardo Sanz, Jordi Llop, Joan Rosell-Polo, Montserrat Gallart, Alexandre Escolà
2014 Sensors  
This paper presents part of the research work carried out in Spain in the field of sensors for characterizing vineyard canopies and monitoring spray drift in order to improve vineyard spraying and make  ...  Some methods and geostatistical procedures for mapping vineyard parameters are proposed, and the development of a variable rate sprayer is described.  ...  Acknowledgments This work was funded by the Spanish Ministry of Science and Innovation (SAFESPRAY project AGL2010-22304-C04-03 and AGL2010-22304-C04-04, and OPTIDOSA project AGL2007-66093-C04-02 and AGL2007  ... 
doi:10.3390/s140100691 pmid:24451462 pmcid:PMC3926582 fatcat:ncczhcto25cm3ipqm55otwrcqu

Advanced Technologies for the Improvement of Spray Application Techniques in Spanish Viticulture: An Overview [chapter]

Emilio Gil, Jaume Arnó, Jordi Llorens, Ricardo Sanz, Jordi Llop, Joan Rosell-Polo, Montserrat Gallart, Alexandre Escolà
2015 Environmentally Sustainable Viticulture  
This paper presents part of the research work carried out in Spain in the field of sensors for characterizing vineyard canopies and monitoring spray drift in order to improve vineyard spraying and make  ...  Some methods and geostatistical procedures for mapping vineyard parameters are proposed, and the development of a variable rate sprayer is described.  ...  Acknowledgments This work was funded by the Spanish Ministry of Science and Innovation (SAFESPRAY project AGL2010-22304-C04-03 and AGL2010-22304-C04-04, and OPTIDOSA project AGL2007-66093-C04-02 and AGL2007  ... 
doi:10.1201/b18226-10 fatcat:vjwz6ux23vfxlfixtz63fsc3oy

An Improved LAI Estimation Method Incorporating with Growth Characteristics of Field-Grown Wheat

Zhuo Lu, Lei Deng, Han Lu
2022 Remote Sensing  
This study provides a simple and practical method for UAV-based LAI estimation, especially for the application of low-cost RGB sensors in precision agriculture and other fields.  ...  Generally, it is difficult to accurately estimate LAI only using vegetation index in remote sensing (RS), especially for unmanned aerial vehicle (UAV) based RS, as its high-resolution advantage has not  ...  This study proposed an improved LAI estimation method, combining spectral characteristics and crop growth characteristics (canopy height and coverage) to improve the accuracy of wheat LAI estimation based  ... 
doi:10.3390/rs14164013 fatcat:5e35qwmvd5gqpnjchsof6ijweq

Detection of Yunnan Pine Shoot Beetle Stress Using UAV-Based Thermal Imagery and LiDAR

Jingxu Wang, Shengwang Meng, Qinnan Lin, Yangyang Liu, Huaguo Huang
2022 Applied Sciences  
However, few studies have investigated the impact of the leaf area index (LAI) on the accuracy of TIR data-based SDR assessments.  ...  Accordingly, when measuring forest health using TIR data, additional data sources are required to eliminate the negative impact of low LAIs and to improve the monitoring accuracy.  ...  As it is difficult to measure the LAI of shrubs, LiDAR is required for correction, although the results may not be entirely accurate.  ... 
doi:10.3390/app12094372 doaj:6239b71a3f5641468bd892c294e4b2bd fatcat:wwxzztiuurbhvkt3q5jex7q5ey

A Survey on Farmland Crop Information Acquisition [chapter]

Danqin Yi, Haiyan Ji
2014 IFIP Advances in Information and Communication Technology  
In this paper, on the basis of introducing the characteristics of farmland crop data, different farmland crop information acquisition methods are surveyed in detail, sections need to be improved of these  ...  The farmland crop information is the important foundation of developing fine agricultural practice.  ...  [17] used ultrasonic sensors to develop a microcomputer-based measurement system to allow in-situ, nondestructive measurement for the morphological characteristics of bush-type plants.  ... 
doi:10.1007/978-3-642-54344-9_26 fatcat:pic4iqgrxvbgnioikj5o6etggy

Retrieving Leaf Area Index (LAI) Using Remote Sensing: Theories, Methods and Sensors

Guang Zheng, L. Monika Moskal
2009 Sensors  
Then, the methodologies for LAI retrieval with regard to the characteristics of a range of remotely sensed datasets are discussed.  ...  The ability to accurately and rapidly acquire leaf area index (LAI) is an indispensable component of process-based ecological research facilitating the understanding of gas-vegetation exchange phenomenon  ...  Acknowledgements Funding has been provided by the Precision Forestry Cooperative (PFC), University of Washington (UW).  ... 
doi:10.3390/s90402719 pmid:22574042 pmcid:PMC3348792 fatcat:dvnggvw55vdvpi4h7a4woyjh6q

Forest and Crop Leaf Area Index Estimation Using Remote Sensing: Research Trends and Future Directions

Jin Xu, Lindi J. Quackenbush, Timothy A. Volk, Jungho Im
2020 Remote Sensing  
, ground measurements and related environmental factors to mitigate the impacts of model uncertainty and improve LAI estimation.  ...  In terms of scale issues, both spectral and spatial scales impact the estimation of LAI.  ...  [160] proposed an approach (Grading and Upscaling of Ground Measurements, GUGM) that resolves the scale-mismatch issue and maximizes the utility of time-series of site-based LAI measurements.  ... 
doi:10.3390/rs12182934 fatcat:wh3p2pgq35cizailwwv4wlaqje

Vinobot and Vinoculer: Two Robotic Platforms for High-Throughput Field Phenotyping

Ali Shafiekhani, Suhas Kadam, Felix Fritschi, Guilherme DeSouza
2017 Sensors  
Instead, our goal is to show that the architecture, the sensors, and the algorithms for imaging proposed here lend themselves to a reliable, accurate, and fast approach that can be successfully employed  ...  The architecture consists of two robotic platforms: an autonomous ground vehicle (Vinobot) and a mobile observation tower (Vinoculer).  ...  Acknowledgments: This material is based upon work supported by the National Science Foundation under Award Number IIA-1355406 and IIA-1430427.  ... 
doi:10.3390/s17010214 pmid:28124976 pmcid:PMC5298785 fatcat:7m3en72lzbgn7b5hkg6sjcgn6m

Estimating Leaf Area Index in Row Crops Using Wheel-Based and Airborne Discrete Return Light Detection and Ranging Data

Behrokh Nazeri, Melba M. Crawford, Mitchell R. Tuinstra
2021 Frontiers in Plant Science  
Results based on the value of the coefficient of determination (R2) and root mean squared error for predictive models ranged from ∼0.4 in the early season to ∼0.6 for sorghum and ∼0.5 to 0.80 for maize  ...  Linear and nonlinear regression models are investigated for prediction utilizing statistical and plant structure-based features extracted from the LiDAR point cloud data with ground reference obtained  ...  Direct methods, which are based on measuring the area of the leaves directly, are accurate but costly, labor-intensive, and time-consuming.  ... 
doi:10.3389/fpls.2021.740322 pmid:34912353 pmcid:PMC8667472 fatcat:dban7corqvfqbh6tsted2u46du

Intercomparison of Unmanned Aerial Vehicle and Ground-Based Narrow Band Spectrometers Applied to Crop Trait Monitoring in Organic Potato Production

Marston Domingues Franceschini, Harm Bartholomeus, Dirk van Apeldoorn, Juha Suomalainen, Lammert Kooistra
2017 Sensors  
These retrievals are slightly better than those derived from ground-based measurements (RMSE = 7.25 µg·cm −2 , 0.85 m 2 ·m −2 , 0.28 g·m −2 and 6.8%, respectively), for the same period.  ...  In this study, ground-based and UAV spectrometers were compared in the context of organic potato cultivation.  ...  Spectral resolution and spectral response of the sensors probably had low impact in the methodology tested here since bands used to derive vegetation indices from UAV and ground-based measurements ( Table  ... 
doi:10.3390/s17061428 pmid:28629159 pmcid:PMC5492811 fatcat:hgqh6wwqgvbeno7rcyulqgijaa

Georeferenced LiDAR 3D Vine Plantation Map Generation

Jordi Llorens, Emilio Gil, Jordi Llop, Meritxell Queraltó
2011 Sensors  
The use of electronic devices for canopy characterization has recently been widely discussed. Among such devices, LiDAR sensors appear to be the most accurate and precise.  ...  Data regarding the velocity of LiDAR measurements and UTM coordinates of each measured point on the canopy were obtained by applying the proposed transformation process.  ...  Acknowledgements This work was funded by the Spanish Ministry of Science and Innovation (OPTIDOSA project AGL2007-66093-C04-02), and the ERDF (European Regional Development Fund).  ... 
doi:10.3390/s110606237 pmid:22163952 pmcid:PMC3231455 fatcat:a5onqm7wh5f6dlov7y5bseixrm

Comparative Analysis of GF-1 WFV, ZY-3 MUX, and HJ-1 CCD Sensor Data for Grassland Monitoring Applications

Lei Wang, Ranran Yang, Qingjiu Tian, Yanjun Yang, Yang Zhou, Yuan Sun, Xiaofei Mi
2015 Remote Sensing  
Based on spectral field measurements, the characteristic differences of spectral response functions of the sensors were analyzed.  ...  In contrast, the mean difference is small between the NDVIs based on ZY-3 MUX and HJ-1 CCD; (3) Correlation analysis between ground grass-coverage and measured LAI data shows that the three sensor types  ...  LAI and Vegetation Coverage Field Measurements The LAI measurements were performed using a ground-based optical instrument, the Plant Canopy Analyzer (PCA) LAI-2000 (LI-COR Biosciences Inc., Lincoln, NE  ... 
doi:10.3390/rs70202089 fatcat:xaspzsbxkza5xkbzeyo5dqjtwq

Multispectral remote sensing for accurate acquisition of rice phenotypes: Impacts of radiometric calibration and unmanned aerial vehicle flying altitudes

Shanjun Luo, Xueqin Jiang, Kaili Yang, Yuanjin Li, Shenghui Fang
2022 Frontiers in Plant Science  
This phenomenon was determined by the field of view of the sensor and the characteristic of the ground object.  ...  The piecewise empirical line (PEL) method suitable for predicting the reflectance of different ground objects was proposed to accurately acquire the reflectance of multi-altitude images by comparing the  ...  The specific altitude value is determined by the FOV of the sensor and the characteristic of the ground object.  ... 
doi:10.3389/fpls.2022.958106 pmid:36035659 pmcid:PMC9401905 fatcat:ahbplvweivc2daauae4ydmwiwy

Testing the Suitability of a Terrestrial 2D LiDAR Scanner for Canopy Characterization of Greenhouse Tomato Crops

Jordi Llop, Emilio Gil, Jordi Llorens, Antonio Miranda-Fuentes, Montserrat Gallart
2016 Sensors  
A 27 general overview of the results show an overestimation of the parameters with manual 28 measurements due to the high definition of the profile obtained with this sensor.  ...  The LiDAR scanner is based on the 92 principle of Time-Of-Flight (TOF) to calculate distances, i.e., the sensor measures the elapsed time 93 between a laser beam emission and reception and automatically  ...  Acknowledgments: This work was funded by the Spanish Ministry of Economy and  ... 
doi:10.3390/s16091435 pmid:27608025 pmcid:PMC5038713 fatcat:6perraizyzh7plpdrwy3zaww5u
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