农田蒸散量计算方法的比较研究

A comparative study on calculation methods of field evapotranspiration

根据观测资料 ,采用波文比法、廓线梯度法和综合阻抗法等分别计算了农田植被层上的蒸散量 ,并对比分析了不同方法之间的相对误差和相关程度。结果表明 ,用波文比法计算的潜热通量存在系统性偏小的现象 ,而梯度法和综合阻抗法的计算结果比较一致。

Based on the experimental data from wheat fields, the evapotranspiration has been estimated using Bowen ratio energy balance(BREB) method,profile gradient(PG) method and energy balance aerodynamic resistance(EBAR) method respectively.Estimations and their errors are compared among the different methods with the error causes under discussion.Results show that the latent heat flux calculated by the BREB method is systematically about 20% lower than by the PG method and slightly less than by the EBAR method.