A new model for water balance estimation on lettuce crops using effective diameter obtained with image analysis

摘要: Digital processing and analysis of vegetation cover images allow a precise calculation some parameters related to crop development, which are linked the estimation irrigation requirements plants. In this paper, new methodology for visual monitoring horticultural crops computation corresponding water needs is presented. The proposed approach based on concept effective diameter, defined as equivalent diameter plant biomass seen from top view. It has been applied ‘Little Gem’ lettuce crop. percentage green (PGC), computed by means digital captured coverage images, used provide accurate estimates Then, value can be precisely with important in agronomy such root depth, height plants, coefficient Kc. Since Kc an essential parameter most existing methodologies balance estimation, extensive comparative study accuracy respect two alternative methods conducted. first PGC density data, while second exclusively image analysis. method behaved significantly better all cases, yielding determination, R2, actual values obtained Bowen station always above 0.95, maximum relative error only 2.1%. Moreover, also produced depth R2 0.986 below 9%. This not leads reduction consumption compared traditional methods, but it simplifies required computations field equipment.