Abstract In this study, PM10 aerosol samples were collected at 4 urban and 1 rural sites in the region of Cienfuegos (Cuba) and analyzed for their chemical compositions (total carbon (TC), total nitrogen (TN), NH4+, Cl−, NO3− and SO42−) and their stable carbon (δ13C) and nitrogen (δ15N), and radioactive (210Pb, 7Be, 137Cs and 40K) isotope systematics, in order to better constrain both their sources of pollution and their atmospheric dynamics. The average PM10 concentrations varied from 21.67 ± 8.54 μg m−3 at the rural site to 39.01 ± 8.23 μg m−3 at an urban site characterized by high road traffic. Chemical compositions showed low variability and similar abundances of the ionic species, but we observed strong correlations between i) NH4+ and SO42− that indicates the formation of secondary ammonium bisulfate (NH4HSO4), and ii) between PM10 and TC highlighting the significant influence of carbonaceous aerosols. We are reporting here the first 210Pb aerosol concentrations in this region and demonstrate that, coupled with the corresponding 7Be concentrations, they allow characterizing the dynamics of the regional continental air masses. δ13C values in PM10 appear to be controlled by i) emissions from different types of combustion sources, including fossil fuel and biomass burning and ii) carbonate inputs from the industrial activities located around the limestone quarries, east of the city. δ15N values presented large isotope variations that can be explained by kinetic processes and the exchange between gas (NH3) and particle (NH4+) phases during the formation of secondary NH4HSO4, a reaction that was enhanced as Cl− concentrations decreased, revealing the preponderant role of local emissions in the budget of the aerosol nitrogen. This study confirms that isotope analysis is reliable for tracing the origin of aerosols and highlight the importance of a multi-isotope approach.

中文翻译：

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使用多稳定和放射性同位素和离子组成阐明西恩富戈斯（古巴）PM10 气溶胶的来源和动态

摘要 在这项研究中，在西恩富戈斯（古巴）地区的 4 个城市和 1 个农村地点收集了 PM10 气溶胶样本，并分析了它们的化学成分（总碳 (TC)、总氮 (TN)、NH4+、Cl−、NO3 − 和 SO42−) 及其稳定的碳 (δ13C) 和氮 (δ15N) 以及放射性（210Pb、7Be、137Cs 和 40K）同位素系统，以更好地限制其污染源和大气动力学。PM10 的平均浓度从农村地区的 21.67 ± 8.54 μg m-3 到道路交通繁忙的城市地区的 39.01 ± 8.23 μg m-3 不等。化学成分显示出离子种类的低变异性和相似的丰度，但我们观察到 i) NH4+ 和 SO42− 之间的强相关性，这表明形成了仲硫酸氢铵 (NH4HSO4)，和 ii) PM10 和 TC 之间，突出了碳质气溶胶的显着影响。我们在这里报告了该地区的第一个 210Pb 气溶胶浓度，并证明，加上相应的 7Be 浓度，它们可以表征区域大陆气团的动态。PM10 中的 δ13C 值似乎受 i) 不同类型燃烧源的排放控制，包括化石燃料和生物质燃烧，以及 ii) 来自城市东部石灰石采石场周围工业活动的碳酸盐输入。δ15N 值呈现出较大的同位素变化，这可以通过动力学过程以及二次 NH4HSO4 形成过程中气体 (NH3) 和颗粒 (NH4+) 相之间的交换来解释，这种反应随着 Cl− 浓度的降低而增强，揭示了局部排放在气溶胶氮预算中的主导作用。这项研究证实同位素分析对于追踪气溶胶的来源是可靠的，并强调了多同位素方法的重要性。