Determinação de zonas homogêneas de evapotranspiração de referência

The present work presents a proposal for a methodology for the creation of a homogeneous zones map of evapotranspiration of reference with the objective of assisting the management of irrigation by central pivots of the delimited region. We analyzed the climatological water balance in the region which indicated the months of August, September and October as the most critical months for irrigation management. The interpolation of monthly data were made by ordinary kriging with Gaussian model of the experimental semivariograms. The maps of the most critical months superimposed to homogeneous zones and validating the map proposed by the evaluation occurred from the correlation coefficients (r), coefficient of determination (R2), the root mean squared error (REMQ) and concordance index (d) applied to observed and estimated data. The high rates obtained by the proposed methodology indicate that the map adjusted properly and the monthly table obtained as result can assist in the management of irrigation by central pivots in the region bounded.