土壤蒸发强度随土壤溶液盐分的变化研究

摘要

采用室内试验方法，研究不同种类盐分在相同土质、相同供水条件以及相同外界环境条件下，土壤蒸发强度随土壤溶液盐分的种类和浓度的变化规律。研究结果表明：在同等条件下，含盐土壤蒸发强度小于不含盐土壤，而且随着盐分浓度的增加，其蒸发强度逐渐减小，但各试验组蒸发强度随盐分浓度的变化规律有所差异；在一定的浓度条件下盐分浓度的增加对蒸发速率影响不大，超过了一定浓度范围，盐分浓度越大，蒸发速率越小。不同种类含盐试验组处于相同的初始盐分浓度情况下，蒸发速率呈现出比较明显的差异，即KCl ＞CaCl2＞NaCl ＞MgSO4。%Indoor experiments were carried out to research the variation of soil’s evaporation intensity with salinity (type and concentration)in soil solutions in the presence of the same soil properties,same water supply conditions and external conditions.Results reveal that in the same condition,the evaporation intensity of saline soil is smaller than that of salt-free soil,and with the increase of salt concentration,the evaporation intensity decreases.But the evaporation intensity in different tests changes with salt concentration variation.In the presence of a certain salini-ty,the increment of saline concentration has little effect on evaporation,but when it exceeds a certain range,the e-vaporation rate reduces with the increase of salinity.At the same initial salt concentration (different salt types), the evaporation intensity of KCl solution is the largest,followed by CaCl2 ,NaCl,and MgSO4 .