上海市霾与非霾期间PM_(2.5)中水溶性阳离子污染特征对比

Comparative Study on Water-Soluble Cationic of PM_(2.5) during Haze and Non-Haze Episodes in Shanghai

霾污染是颗粒物和气体污染物导致的可察觉到的能见度降低的天气污染现象,主要为PM2.5污染,水溶性阳离子是PM2.5的主要成分。为了探讨霾与非霾期间PM2.5水溶性阳离子污染特征,对上海市的PM2.5颗粒物连续采样1个月,利用离子色谱分析了K+、Na+、NH+4、Ca2+、Mg2+5种水溶性阳离子。结果表明,上海市霾天气期间PM2.5的日均质量浓度(103.03μg/m3)是非霾天气日均质量浓度(37.64μg/m3)的2.74倍,Na+、NH+4、Ca2+、Mg2+和K+的质量浓度分别为6.28、1.74、1.42、0.20和0.23μg/m3,PM2.5中水溶性阳离子组分占PM2.5质量浓度的20%左右。对大气气溶胶污染物、水溶性阳离子及气象因素相关性进行分析显示各污染物之间的相关性存在显著差异,其中NOX、NO和CO,SO2和NO2,Na+和CO,Mg2+和CO、NOX,可能存在共同来源。霾动态变化过程分析表明,水溶性阳离子浓度在霾与非霾天气时发生较大变化,Na+、Ca2+和Mg2+是霾天气的主要污染阳离子。

Haze is a weather pollution phenomenon that can be aware of by decreased visibility due to particulate and gaseous pollutants,mainly is PMa5 pollution. Water-soluble ions is the main component of PMas. To investigate water- soluble cationic pollution characteristics of PMas during haze and non-haze episodes, PMas particulates samples in Shanghai continuously were collected for one month and analyzed K＋, Na＋, NH4＋, Ca2＋, Mg2＋ by using ion chromatography. The results showed that the Shanghai daily mass concentrations of PMa s during haze （103. 03 μg/ma ）was 2. 74 times of the non-haze daily mass concentration （37. 64 μg/m3 ）, and the Na＋, NH4＋, Ca2＋, Mge＋ and K＋ concentrations were 6. 28, 1. 74, 1. 42, 0. 20, 0. 23 μg/m3, respectively. Water-soluble cationic component mass concentration accounted for about 200//oo of total PMe2＋. Correlation analysis showed that significant differences of correlation between various pollutants. CO,Nox ,NO and SO2 and Noe ,Nav and CO,Mgz＋ and CO,Nox ,Mge＋ and K＋ may exist a common sourc Analysis of dynamic change process indicated that water-soluble cationic concentration changed greatly in haze and non-haze weather,and Na＋ ,Ca2＋ , Mg2＋ were the main pollution components.