Climatic variables are essential for understanding the environmental conditions that influence plant growth and development. In the last years, research works which use climatic data and remote sensing techniques in spatial and temporal analyses of the demand for water and energy in plants has been intensified. SEBAL (Surface Energy Balance Algorithms for Land) is one of the most prominent algorithms for studies involving energy flow estimates in large areas, and it can be applied with few field measurements. The objective of this work, conducted in the municipality of Santa Bárbara, Minas Gerais, Brazil, was to estimate energy balance components, and therefore the evapotranspiration in eucalyptus crops by applying the SEBAL algorithm and TM sensor image of the Landsat 5 satellite. Estimates were made for the scene on day 6/20th/2003. Considering only the areas related to the eucalyptus crops at seven years of age, it was obtained mean values of net radiation (Rn), soil heat flux (G), sensible heat flux (H) and latent heat flux (LE) of 420.12 W m-2, 81.80 W m-2, 149.93 W m-2, 188.39 W m-2, respectively. For actual hourly evapotranspiration (ETr h), the mean value obtained was 0.28 mm h-1. The estimates are consistent with literature data, but future studies with greater experimental control should be carried out.
Eucalyptus plantation; Energy fluxes; Remote sensing
