大气颗粒物中水溶性离子分布特征比较分析

Distribution Characteristics of Water-soluble Ion in Airborne Particles

论述了不同国家不同地区的大气颗粒物中水溶性离子的污染状况,对水溶性离子的浓度水平、时间和空间分布及其在不同粒径颗粒物上的分布特征进行了综述。中国和印度的城市大气颗粒物中水溶性离子的浓度普遍较高,主要为SO_4^(2-)、NO_3^-、NH_4^+和Ca^(2+)。总的水溶性离子质量浓度呈现出冬季>秋季>春季>夏季的季节分布特征,不同水溶性离子的季节变化特征具有差异性。由于地理位置和功能区不同,不同地区颗粒物中水溶性离子浓度有所不同,一般情况下,工业区的水溶性离子质量浓度高于其他区域。NH_4^+和K^+主要分布在细粒子中,F^-、Mg^(2+)和Ca^(2+)主要分布在粗粒子中,SO_4^(2-)、NO_3^-、Na^+和Cl^-在粗、细粒子中均有分布,水溶性离子粒径分布也表现出随季节变化的特征。

The pollution of water-soluble ion in airborne particles was evaluated among different countries and regions, and the concentration, temporal and spatial distribution features, composition and distribution characteristics of water-soluble ion in airborne particles were compared among cities. The concentrations of water-soluble ion in the cities of China and India were generally higher than the cities in other countries, and the main ion species were, SO4（2-）,NO3-, NH4＋and Ca（2＋）. The concentration of total water-soluble ion had an obvious seasonal variation. The highest concentration of water-soluble ions appears in winter, followed by autumn, spring and summer, and each type of water-soluble ion showed its different characteristics in four seasons. Due to the geographical location and the function,the composition of water-soluble ion in particulate matter differed among functional areas. The concentrations of water-soluble ion were higher in industrial areas. and K＋were mainly distributed in fine particles; F-, Mg（2＋）and Ca（2＋）were mainly distributed in coarse particles; SO4（2-）,NO3-, Na＋and Cl-were distributed in both coarse and fine particles.Size distribution of water-soluble ions also showed the characteristics of seasonal variation.