运用连续颗粒物采样仪（URG Model 2000-01J）对贵阳市城区大气颗粒物PM2.5进行了连续3个月（9-11月）的采集与分析,探讨了PM2.5的浓度分布特征、气象条件的影响。结果显示,贵阳市大气颗粒物PM2.5的平均质量浓度为53±27μg/m^3,变化范围为3.7-186μg/m^3;初步推断大气颗粒物PM2.5的污染来源主要是燃料燃烧、生物质燃烧、汽车尾气等人为源;相对湿度、风速、风向、温度等气象条件是影响大气颗粒物浓度及分布的重要因素。
The increasing emission of primary and gaseous precursors of secondarily formed atmospheric particulate matter due to continuing industrial development and urbanization are leading to an increased public awareness of environmental issues and human health risks in China.As part of a pilot study, 12-h integrated fine fraction particulate matter(PM_(2.5) filter samples were collected to chemically characterize and investigate the sources of ambient particulate matter in Guiyang City, Guizhou Province, southwestern China. Results showed that the 12-h integrated PM_(2.5) concentrations exhibited a daytime average of 51 ± 22 lg m^(-3)(mean ± standard deviation) with a range of 17–128 lg m^(-3) and a nighttime average of55 ± 32 lg m~(^(-3)) with a range of 4–186 lg m^(-3). The 24-h integrated PM_(2.5) concentrations varied from 15 to157 lg m~(^(-3)), with a mean value of 53 ± 25 lg m^(-3), which exceeded the 24-h PM_(2.5) standard of 35 lg m^(-3) set by USEPA, but was below the standard of 75 lg m^(-3), set by China Ministry of Environmental Protection. Energy-dispersive X-ray fluorescence spectrometry(XRF) was applied to determine PM_(2.5) chemical element concentrations. The order of concentrations of heavy metals in PM_(2.5) were iron(Fe) [ zinc(Zn) [ manganese(Mn) [ lead(Pb) [ arsenic(As) [ chromium(Cr). The total concentration of 18 chemical elements was 13 ± 2 lg m^(-3),accounting for 25% in PM_(2.5), which is comparable to other major cities in China, but much higher than cities outside of China.
Longchao LiangNa LiuMatthew S. LandisXiaohang XuXinbin FengZhuo ChenLihai ShangGuangle Qiu
Continuous measurements of speciated atmospheric mercury(Hg), including gaseous elemental mercury(GEM), particulate mercury(PHg), and reactive gaseous mercury(RGM) were conducted in Guizhou Province, southwestern China. Guiyang Power Plant(GPP),Guiyang Wujiang Cement Plant, Guizhou Aluminum Plant(GAP), and Guiyang Forest Park(GFP) in Guiyang were selected as study sites. Automatic Atmospheric Mercury Speciation Analyzers(Tekran 2537A) were used for GEM analysis. PHg and RGM were simultaneously collected by a manual sampling system, including elutriator, coupler/impactor, KCl-coated annular denuder, and a ?lter holder.Results show that different emission sources dominate different species of Hg. The highest average GEM value was 22.2 ± 28.3 ngám^(-3)and the lowest 6.1 ± 3.9 ngám^(-3),from samples collected at GPP and GAP, respectively. The maximum average PHg was 1984.9 pgám^(-3)and the minimum average 55.9 pgám^(-3), also from GPP and GAP,respectively. Similarly, the highest average RGM of 68.8pgám^(-3)was measured at GPP, and the lowest level of20.5 pgám^(-3)was found at GAP. We conclude that coal combustion sources are still playing a key role in GEM;traf?c contributes signi?cantly to PHg; and domestic pollution dominates RGM.
利用连续颗粒物采样仪（URG Model 2000-01 J）和黑碳仪（Aethalometer）对贵阳市城区2008年9—11月大气黑碳浓度进行了连续观测,结果表明,贵阳市城区秋冬季大气24h黑碳浓度变化范围为1.6~12μg.m-3,平均值为4.1μg.m-3;12 h黑碳浓度观测值主要分布在2~5μg.m-3,白昼黑碳浓度变化范围介于1.9~9.2μg.m-3,平均值3.9μg.m-3,夜间黑碳浓度变化范围0.48~15μg.m-3,平均值4.3μg.m-3;黑碳浓度与大气PM2.5浓度变化一致,呈正相关关系（r=0.84,P〈0.0001,n=178）,大气黑碳浓度的变化趋势还明显受相对湿度、温度和风速的影响。
