Determination of actual evapotranspiration is an important step for simulating the crop growth models in agricultural decision-making process. In this study, actual evapotranspiration (ETa) values for the main crops cultivated in Shahrekord plain, Chaharmahal and Bakhtiari province, Iran, are estimated based on real-time modeling and compared with the results obtained from the remote sensing data. Soil moisture balance was simulated considering the variation rate of crop canopy cover and its effects on evaporation and transpiration parameters. Daily values of ETa were predicted in a repeatable cycle based on the available soil moisture in root zone. Moreover, remote sensing images were analyzed as a data source to achieve the crop water requirement in critical times. For this objective, surface energy balance algorithm for land (SEBAL) was used to characterize the evapotranspiration and then derived ETa. Preliminary results obtained by applying satellite information showed a good agreement between the SEBAL estimates of evapotranspiration fluxes and the corresponding values simulated by the soil moisture estimation technique.

确定实际蒸散量是模拟农业决策过程中作物生长模型的重要步骤。在这项研究中，基于实时模型估算了伊朗沙哈迈哈尔邦和巴赫蒂亚里省Shahrekord平原种植的主要农作物的实际蒸散量（ETa）值，并与遥感数据进行了比较。考虑作物冠层覆盖率的变化率及其对蒸发和蒸腾参数的影响，模拟了土壤水分平衡。根据根区中可用的土壤水分，以可重复的周期预测ETa的日值。此外，还分析了遥感图像作为数据源，以在关键时期达到作物需水量。为了这个目标，利用土地表面能平衡算法（SEBAL）表征蒸散量，然后推导ETa。通过应用卫星信息获得的初步结果表明，SEBAL的蒸散通量估算值与土壤湿度估算技术模拟的相应值之间具有良好的一致性。