State Key Joint Laboratory of Environmental Simulation & Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China; Department of Air Pollution Control, Beijing Municipal Institute of Labour Protection, Beijing 100054, China.
State Key Joint Laboratory of Environmental Simulation & Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China; Center for Atmospheric Environmental Studies, Beijing Normal University, Beijing 100875, China.
Environ Pollut. 2018 Feb;233:714-724. doi: 10.1016/j.envpol.2017.10.123. Epub 2017 Nov 7.
PM and its major chemical compositions were sampled and analyzed in January, April, July and October of 2014 at Beijing (BJ), Tianjin (TJ), Langfang (LF) and Baoding (BD) in order to probe the temporal and spatial characteristics as well as source apportionment of PM in the Beijing-Tianjin-Hebei (BTH) region. The results showed that PM pollution was severe in the BTH region. The average annual concentrations of PM at four sampling sites were in the range of 126-180 μg/m, with more than 95% of sampling days exceeding 35 μg/m, the limit ceiling of average annual concentration of PM regulated in the Chinese National Ambient Air Quality Standards (GB3095-2012). Additionally, concentrations of PM and its major chemical species were seasonally dependent and demonstrated spatially similar variation characteristics in the BTH region. Concentration of toxic heavy metals, such as As, Cd, Cr, Cu, Mn, Ni, Pb, Sb, Se, and Zn, were higher in winter and autumn. Secondary inorganic ions (SO, NO, and NH) were the three-major water-soluble inorganic ions (WSIIs) of PM and their mass ratios to PM were higher in summer and autumn. The organic carbon (OC) and elemental carbon (EC) concentrations were lower in spring and summer than in autumn and winter. Five factors were selected in Positive Matrix Factorization (PMF) model analysis, and the results showed that PM pollution was dominated by vehicle emissions in Beijing, combustion emissions including coal burning and biomass combustion in Langfang and Baoding, and soil and construction dust emissions in Tianjin, respectively. The air mass that were derived from the south and southeast local areas around BTH regions reflected the features of short-distant and small-scale air transport. Shandong, Henan, and Hebei were identified the major potential sources-areas of secondary aerosol emissions to PM.
于 2014 年 1 月、4 月、7 月和 10 月在北京（BJ）、天津（TJ）、廊坊（LF）和保定（BD）采集并分析了 PM 及其主要化学成分，以探究京津冀地区 PM 的时空特征及来源解析。结果表明，京津冀地区 PM 污染严重。四个采样点的 PM 年平均浓度范围为 126-180μg/m，超过 95%的采样日超过 35μg/m，这超过了中国《国家环境空气质量标准》（GB3095-2012）规定的 PM 年平均浓度限值。此外，PM 及其主要化学物质的浓度具有季节性差异，且在京津冀地区表现出空间相似的变化特征。有毒重金属如砷（As）、镉（Cd）、铬（Cr）、铜（Cu）、锰（Mn）、镍（Ni）、铅（Pb）、锑（Sb）、硒（Se）和锌（Zn）的浓度在冬季和秋季较高。二次无机离子（SO、NO 和 NH）是 PM 的三种主要水溶性无机离子（WSIIs），其在夏季和秋季的质量比相对较高。有机碳（OC）和元素碳（EC）的浓度在春季和夏季低于秋季和冬季。正矩阵因子分析（PMF）模型分析中选择了五个因子，结果表明，北京的 PM 污染主要由机动车排放主导，廊坊和保定的 PM 污染主要由燃烧排放（包括燃煤和生物质燃烧）主导，天津的 PM 污染主要由土壤和建筑扬尘排放主导。来自京津冀地区周边地区的南风和东南风反映了短距离和小规模空气传输的特征。山东、河南和河北省被确定为二次气溶胶排放的潜在主要源区。
