鼎湖山地区大气颗粒物中水溶性无机盐粒径分布特征

为研究珠江三角洲大气颗粒物的化学组成特征及其来源，2008年10-11月在中科院华南植物研究所鼎湖山区域大气本底观测站对大气中的颗粒物进行了分级（8级）采样，并对各个粒径段颗粒物中水溶性无机盐进行了分析。结果表明，SO42-、NH4+在小于1.1μm的细粒子中出现浓度峰值；Na+和Cl-在1.1-2.1μm出现浓度峰值；NO3-分别在1.1-2.1和3.3-4.7μm出现两个浓度峰值；K+在0.65-1.1和5.8-9μm两个粒径段出现峰值；而Ca2+和Mg2+的浓度峰值则出现在大于9μm粒径段。

Size Distributions of Water Soluble Ions of Atmosphere in the Mt. Dinghu

In order to study on the characteristics of chemical compositions and the sources of the atmospheric particles in Pearl River Delta Region （PRD）, particle samples were collected with Andersen cascade impactor （8 classes） from the atmosphere in the Mt. Dinghu, the atmospheric baseline monitoring station of PRD region, during the autumn （ from Oct. to Nov.） of 2008, in Guangdong Province. Water soluble ionic concentrations were analyzed in the different size particles. The results indicated as following： ①The highest concentration of SO42-and NH4＋ appeared mainly when the fine particles with the size under 1.1 μm. ②The concentration of K＋ was two modes with the higher concentration at 0.65-1.1 μm, 4.7-5.8 μm; ③The concentration of NO3-、Na＋、 Cl-、Mg2 ＋ and Ca2 ＋ presented mainly within coarse particles with the peak at 4.7-5.8 μm. The peak of SO42-mutual transform between the ＂condensation mode＂ and ＂droplet mode＂, and the droplets mode produced when the humidity air mass from Guangzhou direction.