丘陵赤红壤蒸散量的变化特征及计算模型

分析了南亚热带丘陵赤红壤区蒸散量的动态变化特征．结果表明，蒸散量存在年际变化和显著的季节性变化，月蒸散量最大值是最小值的10．80-15．41倍，湿季期(3-9月)，蒸散量约占年蒸散总量的77％，旱季期(10月一次年2月)，蒸散量约占年蒸散总量的23％．揭示了南亚热带丘陵赤红壤区年降雨总量、3-9月的降雨量足以满足蒸散的需求，而10月一次年2月的降雨量不足以满足蒸散的需求，蒸散将消耗土壤水库贮水的规律．以修正的彭曼公式为基础，建立了南亚热带丘陵赤红壤区蒸散量的计算模型．通过试验实测值与模型计算值的比较，证明计算模型的可靠性程度是非常满意的.

Variation characteristics and calculation model of evapotranspiration in latored soils on hills

The dynamic characteristics of evapotranspiration in latored soil on hills of subtropics regions in south China was analyzed. The results showed that evapotranspiration presented annual and seasonal fluctuations. The maximum monthly evapotranspiration was 10.80-15.41 times of the monthly minimum. The evapotranspiration in wet season (March to September) accounted for about 77% of annual total evapotranspiration, and that in dry season (October to February of next year) accounted for about 23%. Although the amount of annual rainfalls could balance annual total evapotranspiration, rainfalls were insufficient for evapotranspiration in the dry season, and soil water could be depleted by evapotranspiration. Based on the modified Penman equation, the calculation model of evapotranspiration in latored soil on hills of subtropics regions in south China was set up. By comparing modeling results with experimental data, it was proved that the calculation model was very reliable.