江苏如东海涂的土壤蒸发及其对含盐量的影响

THE EFFECT OF EVAPORATION FROM MARINE COASTAL SOIL ON ITS SALTNESS IN RUDONG COUNTY JIANGSU PROVINCE

对用热量平衡法测定的土壤蒸发及同时测定的降水量、地下水位埋深和土壤含盐量等资料分析结果表明:蒸发量的年变化曲线呈双峰型,土壤处于常湿状态;月蒸发量的大小主要由太阳辐射、空气湿度等条件决定;该地虽属湿润气候,但夏季干燥度的月变化甚大;土壤含盐量的日变化及铅直分布均取决于土壤蒸发量;降水可使土壤含盐量下降,但降水过大会使含盐量增加。

The data of soil evaporation measured by heat balance and at the same time the meas-ured precipitation,groundwater level and soil saltness in Rudong County,Jiangsu Proviceshowed:1)The yearly change curve of soil evaporation presents a two-humped mould andthe soil often in humid state;2)The month soil evaporation is mainly dependent on solar ra-diation and air humidity;3)Although humid in climate,this area has a quite large summerdryness monthly change;4)The soil saltness daily change and vertical distribution are deter-mined by soil evaporation;and 5)The precipitation may decrease,but the excessive precipita-tion may increase the soil saltness.