Penman公式是目前国内外计算水面蒸发和可能蒸发的主要方法, 可用于推算某区域实际蒸发量, 但其多为经验公式, 精度受当地小气候和环境影响, 故很多专家学者根据当地小气候和环境对公式进行了修订.为使Penman公式可实际应用于三江平原, 本文利用2011、2012年三江平原大豆田小气候观测资料, 着重对Penman公式的干燥力项 (Ea) 经验公式进行区域适用性修正, 得出Penman公式修正式, 其实测值与模拟值回归方程的截距0.47, 斜率0.71, 相对方差 (RRMSE) 值0.31, 标准误差 (RMSE) 值0.68, 模型效率 (ME) 0.87, 决定系数R2=0.62, 接近理想值, 与修正前Penman公式得出的干燥力Ea相比, 修正后的公式更为精确;以三江平原大豆田的实测蒸散量为依据, 对模型修正前后模拟值和实测值的相对误差进行了检验, 修正后模型年相对误差 (18.41％) 较修正前 (71.39％) 降低了52.98个百分点, 精度明显提高, 说明修正后模型更适用于三江平原地区大豆田生长季地表蒸散量的估算.%Penman formula is the main method to calculate water surface evaporation and possible evaporation in the world, being used to estimate the actual evaporation in a certain area.However, the formula is mostly empirical formula, the accuracy is affected by local microclimate and environment, so many experts and scholars revised the formula according to local microclimate and environment.In order to make the Penman formula applicable to the Sanjiang plain, this paper amended the drying force term (Ea) of the empirical formula according to the microclimate observation data of Sanjiang plain soybean field in 2011 and 2012.According to the regression equation between the measured and simulated data of the revised formula, the intercept was 0.47, the slope was 0.71, the relative variance (RRMSE) was 0.31, the standard error (RMSE) was 0.68, the model efficiency (ME) was 0.87, and the determinant coefficient R2 was 0.62, which was close to the ideal value, indicating that the accuracy was improved significantly compared with the original Penman formula.According to the measured evapotranspiration of soybean field in Sanjiang plain, the annual relative error between the simulated and measured value of the revised model (18.41％) was decreased by 52.98 percentages compared to the original model (71.39％) , which the accuracy of the revised model was obviously improved, indicating that the revised model was more suitable for estimating the surface evapotranspiration of soybean fields in the Sanjiang plain during the growing season.
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