【摘要】 森林蒸散发是影响河川径流的重要因素,但是森林影响蒸散发的机理和综合效应评价一直存在很大的分歧。本文从植物的光谱反射特征出发,分析了影响森林流域蒸散发的能量收支特征和水分的蒸发耗散关系,指出流域蒸散发的数值是由蒸发潜力和供水能力这两个因素的最小值决定的,并在此基础上提出了流域蒸散发计算的分布式模型。按照该模型,可以统一解释在湿润地区(南方)、干旱地区(北方)和半湿润地区森林变化前后的蒸散发差异,为森林蒸散发计算中长期存在的分歧提供了统一的理论解释和分析模式。更多还原

【Abstract】 The evapotranspiration of forest watershed is a key factor impacting the stream flow. But its influence mechanics and evaluation principal are of big disagreement among researchers. Based on the characteristics analysis of plant’s reflecting spectrum, the authors studies the energy income-outcome of forest watershed and its effect on the evapotranspiration. The research found that the evapotranspitation of a watershed depends upon the minimum value of potential evaporation and available water of ground surface. A distributed model of watershed evaporation is proposed based on the spatial distribution of these factors. The difference of evapotranspiration caused by reforestation in different climate condition can be explained by this model. This result provides a universal theoretical base and computation approaches to the forest watershed evapotranspiration calculation that has long disagreement.更多还原