Estimativa de evapotranspiração com sensoriamento remoto suborbital e micrometeorologia em cultura de cana-de-açúcar no litoral do estado da Paraí

Abstract

Understanding the process of evapotranspiration (ET) and its role in the water balance is highly important for efficient agricultural management. Given the need for measurement techniques, the use of indirect methods supported by remote sensing has been consolidated as one of the most effective and widely used approaches. Due to their greater operational versatility compared to satellites, remotely piloted aircraft (RPA) have been increasingly used in this field. In this study, the Priestley-Taylor Jet Propulsion Lab (PT-JPL) method was applied to estimate daily ET in a sugarcane crop located on the coast of Paraíba. For this purpose, the model used orthomosaics obtained from a Phantom 4 Multispectral RPA and micrometeorological data collected from a flux tower. A spatial analysis of the results was also carried out over the tower’s footprint area to confirm the representativeness of the data. The daily ET estimates generated by the PT-JPL model showed good correlation with the observed series, reaching an R² of 0.81. Furthermore, the homogeneity of the area was confirmed by the similarity between the footprint statistics and those of the entire area. The results indicated that the method used and its adaptations were suitable for monitoring sugarcane and effectively represented the ET behavior throughout the crop cycle across the entire area.