Study on the Effect of Acid Snow and Acid Rain on the Ecosystem and Soils

1)在融雪季节，酸性阴离子可能优先从堆积的粒状积雪中洗脱出来。由于早春的融雪或降雨，离子从上层转移到下层，首先洗脱一部分含有大量离子的融化水。为了提高硫酸盐离子从冰上的洗脱，研究了含硫酸盐水形成的球，并进行了融化实验。柱式熔融实验结果表明，先排出水的硫酸盐离子浓度较高，后排出水的硫酸盐离子浓度较低。用溶剂进行熔融实验时，发现硫酸根在冰球中的分布呈偏置曲线。2)实验考察了磷酸盐或铵离子在冰晶表面的吸附现象。准平衡态建立后的吸附量服从Langmuir吸附等温线。因此，我们认为杂质在冰面上的吸附现象导致了偏分布，这可能是冷冻分离的一个重要因素。3)新泻县雨雪的pH值平均为4.6。这个地区的大部分雨雪都被认为是“酸性的”，这肯定对该地区的土壤有影响。在本研究中，通过测量pH值和土壤中溶解元素的化学分析，检查了主要从新泻县收集的土壤的现状。通过实验研究发现，土壤已发生轻微酸化，铝、锰离子在非酸化土壤中溶解度较低，而在酸化土壤中溶解度较高。

1)Acidic anions might be preferentially eluted first from the packed granular snow in the snowmelt season. The ions were transferred to a lower layer from the upper layer due to snowmelt or rain in early spring, and a portion of the melted water containing a large amount of ions is eluted first. In order to enhance the elution of sulfate ions from ice, spheres formed of sulfate-containing water were examined, and melting experiments were performed. The results of the melting experiment using a column showed higher concentrations of sulfate ions in the effluent drained first and lower concentrations in the later effluent. When using the solvent for melting experiment, the distribution of sulfate in an ice sphere was found with a biased curve.2)The adsorption phenomena of phosphate or ammonium ions on the surface of ice crystals were experimentally examined. The amounts adsorbed immediately after the establishment of a quasi-equilibrium state obeyed a Langmuir adsorption isotherm. Therefore, it was suggested that the adsorption phenomena of the impurities on the ice surface caused the biased distribution and should probably be a significant factor in freeze separations.3)The pH of the rain and snow falling in Niigata Prefecture has been found to be 4.6 on average. Most of the rain and snow in this area is considered ‘acidic, it must have an effect on the area s soils. In this study, the present state of soils gathered from mainly Niigata Prefecture was examined by the measurement of pH and the chemical analysis of dissolved elements from the soils. As a result of the experimental study, it was found that soil had become slightly acidified, and aluminum and manganese ions dissolve only slightly out of non-acidified soils, while they dissolve easily out of acidified soils.