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以甘肃景电灌区盐化土壤为对象用水汽平衡吸附法就盐分对土壤的水汽吸附和土壤水能量状态的影响进行了研究 .结果表明盐分显著增加了土壤水汽吸附量 ,水汽饱和度为 98%的情况下 ,含盐量为 1 0 .772 g/kg和 1 2 .887g/kg的两个土壤的水汽吸附量分别达到了 1 9.4 5 %和 2 5 .34 % .水汽饱和度大于65 %左右时水汽吸附有一个明显的转折点 ,.水汽饱和度大于 65 %时水汽吸附量主要受含盐量影响 ,而当饱和度小于 65 %时则主要受物理性粘粒含量的影响 .盐分非常显著地降低了土壤的水势 ,可以用盐化土样的水势与脱盐处理土样的水势估算盐化土样的渗透势 .估算结果表明在低水势段以及在相当大含水量范围内盐化土壤因盐分浓度所产生的渗透势的绝对值远大于基质势的绝对值
The effects of salinity on soil water vapor adsorption and soil water energy status were studied by using water vapor equilibrium adsorption method in saline soil of Gansu Jingdian Irrigation Area.The results showed that salinity significantly increased soil water vapor adsorption capacity and water vapor saturation of 98% , The water vapor adsorption capacities of the two soils with salt contents of 1077g g kg -1 and 12887g kg -1 reached 1 9.45% and 25.34%, respectively, and the water vapor saturations were more than 65% When the water vapor saturation is more than 65%, the amount of water vapor adsorbed is mainly affected by the salinity, while when the degree of saturation is less than 65%, it is mainly affected by the physical clay content. The salinity is very significant Soil water potential can be reduced, soil water potential of saline soil sample and water potential of desalinated soil sample can be used to estimate osmotic potential of saline soil sample. The estimation results show that in the low water potential and salinized soil The absolute value of the osmotic potential generated by the salt concentration is much larger than the absolute value of the matrix potential