乌鲁木齐大气总悬浮颗粒物(TSP)离子化学组分及影响因素

The Features of Ionic Components of TSP and Their Affecting Factors over Urumqi

利用2009年乌鲁木齐4个大气总悬浮颗粒物(TSP)观测站点资料,采用离子色谱仪分析了TSP中水溶性离子成分。结果表明:①2009年乌鲁木齐市区3站总离子浓度为151.28μg/m3,白杨沟为40.83μg/m3。4站NO3-/SO24-比值较小,表明乌鲁木齐大气污染主要来自于固定污染源。②2009年乌鲁木齐4站TSP中SO24-、Ca2+、NO3-和NH4+的浓度高于其他各离子,各站离子浓度有明显的季节变化特征,采暖期各离子浓度明显增加,SO24-、NO3-增幅最大。③对各主要离子进行相关性分析,得到NH4+与SO24-的相关系数为0.828,与NO3-的相关系数为0.659,说明铵盐化合物主要以硫酸铵和硝酸铵的形式存在;SO24-与NO3-的相关性很大,相关系数为0.973,表明二者主要来自二氧化硫和氮氧化物,排放方式与在大气中的传输途径较一致;地壳元素Ca2+和Mg2+有很好的相关性,相关系数是0.914,表明二者来源相似,可能主要来自风沙土壤尘、道路尘和建筑尘。

This paper analyzed the water-soluble ionic components of TSP over Urumqi in 2009 based on the data of atmospheric total suspended particles （TSP） measured with ion chromatographers at 4 observation sites. The results are as follows： （1） The total ion concentration which was averaged with the values measured at three stations over Urumqi City was 151.28 μg/m3 , and the total ion concentration at Baiyang Station was 40.83 μg/m3. The ratio of NO3-/SO24- at all the 4 stations was low, which revealed that the atmospheric pollution was mainly from the fixed pol- lution sources in Urumqi; （2） SO24-, Ca2＋ , NO3- and NH4＋ levels were higher than the other ions of TSP in 2009. There were the significant seasonal variations of concentration of ions. All the concentrations of ions, especially that of SOl- and NO3- , were obviously increased in heating season; （3） Correlation analyses of all the ions were carried out, the results showed that the correlation coefficient between NH4＋ and SO42- was 0.828, and that between NH; and NO3- was O. 659, these revealed that ammonium compounds were dominated by ammonium sulfate and ammonium ni- trate. The correlation coefficient between NO3- and SOl- was 0.973, which revealed that NO3- and SOl- came mainly from sulfur dioxide and nitrogen oxides. There was a good correlation between crust elements Ca2＋ and Mg2＋ , and their correlation coefficient was as high as 0. 914, which revealed that the sources of these two crust elements were similar, and these elements came mainly from dust weather, road dust and construction dust.