the parameters of the simplified simple biosphere model - ssib were validated and subsequently calibrated for the fazenda nossa senhora aparecida (62o22'w; 10o45's) pasture site and the reserva biológica do jaru (62o22'w; 10o45's) forest site, both located in the state of rond？nia. micrometeorological and hydrological data collected during the dry period of 2001, as part of the large-scale biosphere-atmosphere experiment in amazonia - lba, were used. the results showed that the model simulated well the net radiation, both at the pasture and at the forest. the latent heat flux was super-estimated in both sites. the model sub-estimated the sensible heat flux at the pasture and at the forest, mainly during the night period; notwithstanding, the values for the forest were nearer to the observed ones. with the calibrated parameters, the model generated better estimations of the latent and the sensible heat fluxes, thus better representing the energy partition both at the forest and at the pasture.