Histogram and Boxplot were applied to analysis the distribution of pollutants. Distribution range of the daily average concentration of SO2, NO2, PM10 and PM2.5 was clear in Beijing, Shenyang, Guangzhou, Shanghai and Haikou during the first half of2013. This group data involved 49 detection sites, included data of 1863 in Beijing, 1670 in Shenyang, 1452 in Shanghai, 1574 in Guangzhou, 780 in Haikou. Histogram shows the concentration range of four pollutants at the site of each city.ρ(SO2) andρ(NO2) in Beijing is relatively concentrated, respectively the concentration range is 0-40 and 40-80μg·m-3, percentages are 51.0% and 49.7%.ρ(PM10) andρ(PM2.5) are more dispersed.ρ(NO2) andρ(PM2.5) in Shenyang is relatively concentrated, respectively the concentration range is 0-30μg and 30-60μg·m-3, percentages are 52.2% and 42.8%.ρ(SO2) andρ(PM10) are more dispersed.ρ(SO2) in Shanghai and Guangzhou is relatively concentrated in low concentrations, the distribution of other three pollutants is more dispersed. Boxplot is drawn with the average of maximum, minimum, under the upper quartile, quartiles and median for all sites of each city. Through the comparison between the different cities, in the meantime the comparative result order ofρ(SO2) isρ(Shenyang) >ρ(Beijing)>ρ(Guangzhou)>ρ(Shanghai)>ρ (Haikou);ρ(NO2) in Beijing, Shanghai and Guangzhou was higher; Forρ(PM10), the concentrations only in Guangzhou and Haikou were lower than other cities. Forρ(PM2.5), high value is concentrated in Beijing, Guangzhou and Shenyang. Through the comparison between the spectra, and combined with the city's meteorological conditions and economic development, in addition to the background points in Haikou, it’s estimated that the main pollutants in Beijing and Shenyang are PM2.5 and PM10, main pollutants in Guangzhou and Shanghai are NO2 and PM2.5; Beijing's main pollution source is coal soot and automobile exhaust, motor vehicle exhaust in Guangzhou and Shanghai is the main pollution source, major pollution source for Shenyang is coal ash. The results provide scientific basis for the environmental management and air pollution control of typical cities in China.%应用柱状图和箱线图对污染物分布情况进行对比分析，明确了2013上半年北京、沈阳、广州、上海和海口5个城市4项污染物（SO2、NO2、PM10、PM2.5）的日均浓度的分布范围。该组数据涉及的站点总计有49个，其中包含的数据量北京有1863个、沈阳有1670个、上海有1452个、广州有1574个、海口有780个。柱状图显示了这段时间每个城市各个站点4种污染物不同浓度的分布范围，北京的ρ(SO2)和ρ(NO2)分布较为集中，主要的质量浓度区间分别是0~40和40~80μg·m-3，分别占北京SO2和NO2总数据量的51.0%和49.7%，ρ(PM10)和ρ(PM2.5)则分布较为分散；沈阳分布较为集中的是ρ(NO2)和ρ(PM2.5)，主要的质量浓度区间分别是0~30和30~60μg·m-3，分别占沈阳NO2和PM2.5总数据量的52.2%和42.8%，ρ(SO2)和ρ(PM10)则分布较为分散；上海和广州分布较为集中的是低浓度下的ρ(SO2)，其他三项污染物分布较为分散。箱线图是利用每个城市所有站点得到的最大值、最小值、上四分位数、下四分位数和中位数的平均值绘制得到的，通过不同城市间的比较可见，同期ρ(SO2)的比较结果是ρ(沈阳)>ρ(北京)>ρ(广州)>ρ(上海)>ρ(海口)；ρ(NO2)较大的3个城市是北京、上海和广州；对于ρ(PM10)则只有广州和海口2个城市浓度较低，而对于ρ(PM2.5)高值集中在北京、广州和沈阳3个城市。通过谱图间的比较，并结合各个城市的气象条件及经济发展状况，从中可推测除背景点海口外，北京和沈阳主要的污染物是PM2.5和PM10，广州和上海主要的污染物是NO2和PM2.5；北京主要的污染来源是燃煤烟尘和机动车尾气，广州和上海主要的污染来源是机动车尾气，沈阳主要的污染来源是燃煤烟尘。研究结果可为典型城市的环境监管与大气污染控制提供科学依据。
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