【摘要】 应用偏光显微镜技术与扫描电子显微镜技术,对三种不同类型盐土的盐结晶进行观察研究。从土壤溶液的蒸发过程中,我们观察到石膏（CaSO₄·2H₂O）、芒硝（Na₂SO₄·10H₂O）、泻利盐（MgSO₄·7H₂O）、石盐（NaCl）结晶的析出过程,析出顺序受温度的影响。用这种方法可以快速确定土壤溶液中主要盐分类型。扫描电子显微镜的照片,展示出某些盐类结晶的自然特征,它们是:与土粒胶结紧密的石盐（NaCl）、由芒硝（Na₂SO₄·10H₂O）脱水转变成的无水芒硝（Na₂SO₄）、或由硫酸钠、硫酸钙形成的复盐——钙芒硝Na₂Ca（SO₄）₂。各种盐类在土壤中结晶出来形态清晰。以硫酸钠的溶解特性为例,扼要地讨论了土壤中芒硝—无水芒硝的转化条件及其对土壤结构产生的影响。更多还原

【Abstract】 The crystallization of salts in three kinds of saline soil was studied, with polarizing microscope and of scanning electron microscope （SEM）. It was found that the crystallization order depended on temperature, and under different temperature the main salts in soil solution were determined rapidly. The morphology of several salts in soil were studied by SEM Technique. It was found that halite （NaCl） was closely cemented with soil particles, thenardite （Na₂SO₄） was transformed from mirabilite （NasSO₄·VlOH₂O） by dehydration, and the glanberite [Na₂Ca （SO₄）₂] was formed by calcium sulfate and sodium sulfate. These salt crystals separated were clear, without any mixture. They would be formed in complex salt under certain conditions. As an example, the condition which affected the transformation of mirabilite-thenardite and its effect on the development of soil structure are discussed.更多还原