162 research outputs found

    Electronic characterization of the phenological stages of grapevine using a LIDAR sensor

    Get PDF
    Canopy characteristics and their variation at all growth stages, together with the spatial distribution of plants in the field need to be considered in determining the application volume rate in fruit crops. Spray volume calculation in a vineyard needs to take into account concepts such as tree row volume (TRV), leaf wall area (LWA) and leaf area index (LAI). The objective of this work was to develop one protocol to characterize the canopy geometry of grapevine to determine BBCH stages using data sets measured manually and with LIDAR scanning. With this aim, a package called PROcess TO LIdar Data v.0.1 (PROTOLIDAR) was created in R environment to process the LIDAR scan information. Results showed a significant correlation between LIDAR impacts and LAI at each growth stage. The relationship between the estimated values of TRV or LWA, and the growth stage of the vine was statistically significant (R2 = 0.99 and R2 = 0.95, respectively). Finally, the geometry characterizations of the plants were represented in 2 or 3D maps in GRASS-GIS.Postprint (published version

    Variable rate dosing in precision viticulture: Use of electronic devices to improve application efficiency

    Get PDF
    Two different spray application methods were compared in three vine varieties at different crop stages. A conventional spray application with a constant volume rate per unit ground area (1 ha(-1)) was compared with a variable rate application method designed to compensate electronically for measured variations in canopy dimensions. An air-blast sprayer with individual multi-nozzle spouts was fitted with three Ultrasonic sensors and three electro valves on one side, in order to modify the emitted flow rate of the nozzles according to the variability of canopy dimensions in real time. The Purpose of this prototype was to precisely apply the required amount of spray liquid and avoid over dosing. On average, a 58% saving in application volume was achieved with the variable rate method, obtaining similar or even better leaf deposits.This work was funded by the Spanish Ministry of Education and Science, and was part of research project AGL2007-66093-C04-02/AGR. We are grateful to Professor Jordi Valero from Universitat Politècnica de Catalunya for his help in the statistical analysis and Xavier Vidal director of the School of Viticulture “Mercè Rosell” at Espiells (Barcelona) for his help during the field experiments

    Special issue on 'Terrestrial laser scanning': editors' notes

    Get PDF
    In this editorial, we provide an overview of the content of the special issue on 'Terrestrial Laser Scanning'. The aim of this Special Issue is to bring together innovative developments and applications of terrestrial laser scanning (TLS), understood in a broad sense. Thus, although most contributions mainly involve the use of laser-based systems, other alternative technologies that also allow for obtaining 3D point clouds for the measurement and the 3D characterization of terrestrial targets, such as photogrammetry, are also considered. The 15 published contributions are mainly focused on the applications of TLS to the following three topics: TLS performance and point cloud processing, applications to civil engineering, and applications to plant characterization
    corecore