Reference evapotranspiration in the region of Seropédica-RJ using weighting lysimeter and mathematical models

Abstract

The present study aimed to evaluate the estimate of reference evapotranspiration (ETo) for the region of Seropédica, RJ, correlating measures obtained with weighing lysimeter and Penman-Monteith - FAO 56 (PMF), Hargreaves-Samani (HS), Camargo (CA), Priestley-Taylor (PT), Makking (MA) and Pan Class A  (PCA) methods. The values of ETo estimated by PMF, PT and MA were well correlated to those determined by the weighing lysimeter, whereas the HS and CA methods showed unsatisfactory adjustment with the lysimeter data. The estimated mistakes from the adjusted methods for the region of Seropédica are acceptable for use in design and management irrigation systems. Another interesting alternative is the use of the Pan Class A method, due to the feasible handling and low cost, so that it can be installed near the field.