【摘要】 不同潜水埋深下裸地逐旬日平均潜水蒸发过程表现为:夏季最强,春季和秋季较弱,冬季最弱。随着地下水埋深的增加,潜水蒸发量呈现降低的趋势。裸地累计潜水蒸发量随埋深增大而减少,二者符合幂函数关系。当潜水埋深较小时,潜水蒸发与直径20 cm蒸发皿的水面蒸发量的关系接近直线,随着埋深加大,当水面蒸发强度增大到某种程度,曲线的斜率逐渐变小。降水对裸地潜水蒸发的影响主要是2个方面的作用:有降水时大气蒸发能力接近于零,同时降水补给了土壤水而削弱了毛管作用从而降低了潜水蒸发。更多还原

【Abstract】 The process of day average change of phreatic evaporation in bare field at different depth of groundwater table showed that there was a large evaporation ability in summer season,next to in spring and autumn season,the less in winter season.Phreatic evaporation tends to decrease with the increase of depth of groundwater table.The accumulative phreatic evaporation decrease with increase of depth of groundwater table,the relationship of these can be described with power function.There was coincident relation with phreatic evaporation and water surface evaporation by E20 in small depth of groundwater table,when the increase of depth of groundwater table and water surface evaporation ability,the slope of curve decrease gradually.The effect of precipitation on bare field phreatic evaporation main perform two aspect,when the precipitation occur,the atmosphere evaporation ability tend to zero,the precipitation supply to soil water and weaken the capillary effect and decrease of field water evaporation.更多还原