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In 2009, the European Directive for a Sustainable Use of Pesticides (128/2009/CE) established important mandatory actions to be accomplished by all Member States (MS) in the European Union. The main objective is to achieve the sustainable use of pesticides by reducing their risks and impacts on human health and the environment. Among other important actions, drift reduction measures are essential to avoid the entry of plant protection products (PPP) in water or other undesirable areas. As the risk of environmental contamination is directly related to the spray application technology, there is a strong need for objective methods for drift evaluation as well as robust procedures for the classification of sprayers according to their risk of contamination. For this purpose, and as a complementary tool to actual drift measurement methodologies in the field or in laboratory conditions, a new method has been proposed for the quantification of the potential drift generated by horizontal boom sprayer systems using an ad hoc test bench. This study aims to evaluate the influence of wind velocity and wind direction on the drift potential value (DPV) using the proposed methodology and test bench. The results indicated that wind velocities below 1.0 m s −1 have a negligible influence on the DPV. Front wind led to higher DPVs than lateral wind. A global analysis of data indicates that the proposed methodology and test bench are interesting tools for the quick and objective evaluation of the potential drift if used in appropriate environmental conditions. [ABSTRACT FROM AUTHOR]

Abstract: In recent years, LIDAR (light detection and ranging) sensors have been widely used to measure environmental parameters such as the structural characteristics of trees, crops and forests. Knowledge of the structural characteristics of plants has a high scientific value due to their influence in many biophysical processes including, photosynthesis, growth, CO2-sequestration and evapotranspiration, playing a key role in the exchange of matter and energy between plants and the atmosphere, and affecting terrestrial, above-ground, carbon storage. In this work, we report the use of a 2D LIDAR scanner in agriculture to obtain three-dimensional (3D) structural characteristics of plants. LIDAR allows fast, non-destructive measurement of the 3D structure of vegetation (geometry, size, height, cross-section, etc.). LIDAR provides a 3D cloud of points, which is easily visualized with Computer Aided Design software. Three-dimensional, high density data are uniquely valuable for the qualitative and quantitative study of the geometric parameters of plants. Results are demonstrated in fruit and citrus orchards and vineyards, leading to the conclusion that the LIDAR system is able to measure the geometric characteristics of plants with sufficient precision for most agriculture applications. The developed system made it possible to obtain 3D digitalized images of crops, from which a large amount of plant information – such as height, width, volume, leaf area index and leaf area density – could be obtained. There was a great degree of concordance between the physical dimensions, shape and global appearance of the 3D digital plant structure and the real plants, revealing the coherence of the 3D tree model obtained from the developed system with respect to the real structure. For some selected trees, the correlation coefficient obtained between manually measured volumes and those obtained from the 3D LIDAR models was as high as 0.976. [Copyright &y& Elsevier]