COSTA, Patricia Cordão.
Resumo:
The evapotranspiration (ETc) from a drip irrigated banana orchard cv. Pacovan Apodi (Musa sp., AAAB), located in Fazenda Frutacor (5° 4' 35'' S; 37° 51' 54'' W; 131m), in Quixeré-CE was measured using the Eddy Covariance Method from September 2005 to September 2006. Besides, it was also considered the reference evapotranspiration (ETo) to achieve the crop coefficient (Kc) of the orchard. Water use efficiency (WUE) was obtained from yield and crop evapotranspiration. It has been accomplished energy balance over canopy that allowed to define the net radiation partition for the others components, that are, latent and sensible heat flux and soil heat flux, besides energy balance closure error was obtained. Daily average values of ETc for whole experimental period were in the strip from 1,67 to 4,53 mm day-1, with average of 3,40 mm day-1. Minimum value of crop coefficient was 0,55 and maximum, 1,0. In regarding to net radiation partition used as the latent heat flux was between 0,5 and 0,92 (adimensional), with average value of 0,68. Fraction of sensible heat flux was 0,13 to 0,44, with average value 0,28, while fraction used in soil heat flux was 0,04 to 0,12, which its average achieved 0,03. Closure error of energy balance equation, attained through correlation
between Rn – G and H + LE, was about 20%, which is similar to that found in others
researches.