淮河流域蒸散发能力估算研究

蒸散发能力是水文模型的重要输入项,合理估算流域蒸散发能力直接影响流域产流量的计算精度。选取淮河息县以上流域为研究区,构建考虑土壤蒸发和植物散发的分布式双源蒸散发能力计算模型,并将能逐日动态模拟叶面积指数的植物生长模型与其集成,以日为时间尺度,基于流域土地利用、气象和植物生长资料,计算了2000-2008年研究区每个1 km×1 km栅格的蒸散发能力,并将蒸发皿所在网格的蒸散发能力计算值与蒸发皿观测得到的水面蒸发值进行了相关性分析。结果表明:模型计算的蒸散发能力能较好地反映流域实际蒸散发能力,可以为分布式水文模型提供蒸散发能力输入资料。研究成果为淮河流域蒸散发能力的计算提供了新的途径,对其它流域蒸散发能力的计算也具有参考价值。

Research on estimation of evapotranspiration in upperstream of Huaihe Basin

The capacity of evapotranspiration is an important input part of hydrology model and its rational estimation has direct impact on the precision of runoff calculation.This paper built the dual-source potential evapotranspiration distributed model considering soil evaporation and vegetation evaporation with the input of daily LAI calculated by EPIC model in the upperstream of Huaihe basin. Based on the data of land use, meteorological and plant growth,the paper computed the capacity of evapotranspiration every grid with the size of 1km×1km from 2000 to 2008 and then made the correlation analysis between calculated value and measured value in three evaporation stations. The results revealed that the evapotranspiration capacity calculated by the model can better reflect the real capacity of evapotranspiration and can provide reliable evapotranspiration input for distributed hydrology model. The result can provide a new way for the calculation of evapotranspiration in Huaihe Basin and has reference value for other similar basins.