Department of Civil Engineering, Louisiana State University, Baton Rouge, LA 70803, USA.
Department of Civil Engineering, Indian Institute of Technology Guwahati, 781039, India.
Sci Total Environ. 2017 May 15;586:115-126. doi: 10.1016/j.scitotenv.2017.01.189. Epub 2017 Feb 1.
Particulate matter with aerodynamic diameter <2.5μm (PM) chemical composition data from the Speciation Trends Network (STN) site located in Baton Rouge, Louisiana were analyzed using the receptor Positive Matrix Factorization (PMF) model version 5.0. The PM samples were collected every third day from January 2009 to December 2014. Seven sources were identified, including secondary sulfate, secondary nitrate, industrial emissions, traffic, crustal dust, road dust and sea salt. The contributions of these seven sources to PM total mass were 38.4%, 17.6%, 18.7%, 11.5%, 6.1%, 4.2% and 3.6%, respectively. Secondary sulfate, industrial emissions and secondary nitrate were the top three sources. The contributions of industrial emissions and crustal dust have been rising in recent years while that of traffic and sea salt were decreasing. Secondary sources were higher than primary sources during the winter. The crustal and road dust were dominant during the summer, while traffic was more significant during the fall compared to other seasons. During summer, traffic emission and crustal dust were driven by northeast-north winds, traffic is also driven by northeast-north winds in winter, while industry emissions and sea salt were driven by prevailing west and northwest winds during other seasons. PM mass clearly showed the synergetic effects of local sources and distance sources. Thus, measurements and strategies should focus on not only local sources, but also regional transport. Attention should also be paid to industrial and traffic sources since they also account for secondary sources in addition to the primary contributions.
来自路易斯安那州巴吞鲁日 Speciation Trends Network (STN) 站点的空气动力学直径 <2.5μm 的颗粒物 (PM) 化学成分数据，使用受体正矩阵因子化 (PMF) 模型版本 5.0 进行了分析。PM 样品于 2009 年 1 月至 2014 年 12 月每三天采集一次。共鉴定出 7 种源，包括二次硫酸盐、二次硝酸盐、工业排放、交通、地壳灰尘、道路灰尘和海盐。这 7 种源对 PM 总质量的贡献分别为 38.4%、17.6%、18.7%、11.5%、6.1%、4.2%和 3.6%。二次硫酸盐、工业排放和二次硝酸盐是前三大源。近年来，工业排放和地壳灰尘的贡献呈上升趋势，而交通和海盐的贡献呈下降趋势。冬季二次源高于一次源。夏季地壳和道路灰尘占主导地位，而秋季交通比其他季节更为重要。夏季，交通排放和地壳灰尘受东北偏北风驱动，冬季交通也受东北偏北风驱动，而其他季节工业排放和海盐则受盛行的西风和西北风驱动。PM 质量明显显示出本地源和远距离源的协同效应。因此，测量和策略不仅应侧重于本地源，还应侧重于区域运输。还应注意工业和交通源，因为它们除了对一次源有贡献外，还构成了二次源。
