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土壤地表蒸发是一个复杂的过程,它的正常进行受到诸多因素的影响,其中土壤盐分是蒸发的主要影响因素之一。以内蒙古河套灌区永联试验站含盐土壤为例,通过室内试验盐分含量分别为0.2%、0.6%、1.0%、5.0%的土壤水分、盐分的变化以及对蒸发的影响进行了分析。试验结果表明:实验进行的初始阶段土壤剖面中含水率变化是比较显著,地下水补给对土壤蒸发的影响较大,实验持续到第15天之后随着土壤含水率的稳定变化,土壤蒸发量慢慢下降,这个时间段土壤水分迁移主要被土壤盐分控制。实验开始的前一段时间土壤水分对盐分的影响不太明显,实验持续到15天之后,尤其是,土壤表层形成盐壳之后,土壤水分对含盐量的影响以及盐分对水分的相应反馈比较明显。同一个时间来看,盐分含量高的土壤水分比较低。不同盐分含量的土壤中随着含盐量的增加,土壤蒸发速率减小。通过分析可知土壤含盐量与蒸发量具有很好的相关性,盐分越高,相关性越好。
Soil surface evaporation is a complex process, its normal progress is affected by many factors, including soil salinity is one of the main evaporation factors. Taking Salt Soil in Yonglian Experimental Station of Hetao Irrigation District in Inner Mongolia as an example, the soil moisture, salinity changes and the impact on evaporation of salt content of 0.2%, 0.6%, 1.0% and 5.0% in laboratory were analyzed. The experimental results show that: the initial stage of the experiment changes in the soil moisture content of the soil profile is more significant, groundwater recharge on the impact of soil evaporation greater experiment until the 15th day with the steady changes in soil moisture, soil evaporation slowly Decline, this period of time soil moisture migration is mainly controlled by soil salinity. The effect of soil moisture on salinity was not obvious until the experiment began 15 days later, especially after the formation of the salt shell on the surface of the soil. The influence of soil moisture on salt content and the corresponding feedback of salt to water were obvious . At the same time, soil moisture with high salt content is relatively low. The soil evaporation rate decreased with the increase of salinity in soils with different salt content. Through the analysis shows that soil salinity and evaporation have a good correlation, the higher the salt, the better the correlation.