Fractional iron solubility of aerosol particles enhanced by biomass burning and ship emission in Shanghai, East China
Fractional iron solubility of aerosol particles enhanced by biomass burning and ship emission in Shanghai, East China
复制标题
上海生物质燃烧和船舶排放增强气溶胶颗粒的铁溶解度
DOI：
10.1016/j.scitotenv.2014.01.118
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发表时间：
2014-05-15
影响因子：
9.8
通讯作者：
Chen, J. M.
中科院分区：
文献类型：
--
作者：
Fu, H. B.;Shang, G. F.;Chen, J. M.
为了解华东地区气溶胶颗粒对铁的动员作用，在春季采集了上海地区的PM2.5颗粒。结合反轨迹分析、PM2.5/PM10和Ca/Al比值，确定了采样期间的严重沙尘暴事件。单颗粒分析结果表明，DSE期间含铁主要为铝硅酸盐粉尘，非沙尘暴日含铁气溶胶以粉煤灰为主，其次为少量氧化铁。样品的化学分析表明，NDS过程中Fe溶解度分数（%Fe-s）远高于DSE过程，且%Fe-s与大气总铁负荷呈R-2 = 0.967的强反比关系，表明总铁（Fe- t）不控制采样过程中可溶铁（Fe-s）。此外，Fes与任何酸性物质之间没有关系，这表明气溶胶表面的酸性过程与铁的溶解度趋势无关。因此，提出气溶胶颗粒的源相关组成是%Fe-s的主要决定因素。其中，Al/Fe比与%Fe-s的相关性较差（R-2 = 0.113），而%Fe-s与计算的K-BB(+)/Fe比（R-2 = 0.888）和V/Fe比（R-2 = 0.736）之间存在明显的关系，反映了%Fe-s可以由生物质燃烧和船舶排放的油灰控制，而不是矿物颗粒和煤飞灰控制，尽管后者是采样过程中大气Fe负荷的主要来源。这些信息有助于提高我们对华东地区铁溶解度的理解，这可能进一步与铁对海洋的生物利用度有关，以及与中国人口密集的大都市暴露于富铁细颗粒对人类健康的影响有关。(C) 2014 Elsevier B.V.版权所有
In terms of understanding Fe mobilization from aerosol particles in East China, the PM2.5 particles were collected in spring at Shanghai. Combined with the backtrajectory analysis, the PM2.5/PM10 and Ca/Al ratios, a serious duststorm episode (DSE) during the sampling was identified. The single-particle analysis showed that the major ironbearing class is the aluminosilicate dust during DSE, while the Fe-bearing aerosols are dominated by coal fly ash, followed by a minority of iron oxides during the non-dust storm days (NDS). Chemical analyses of samples showed that the fractional Fe solubility (%Fe-s) is much higher during NDS than that during DSE, and a strong inverse relationship of R-2 = 0.967 between %Fe-s and total atmospheric iron loading were found, suggested that total Fe (Fe-T is not controlling soluble Fe (Fe-s) during the sampling. Furthermore, no relationship between Fes and any of acidic species was established, suggesting that acidic process on aerosol surfaces are not involved in the trend of iron solubility. It was thus proposed that the source-dependent composition of aerosol particles is a primary determinant for %Fe-s. Specially, the Al/Fe ratio is poorly correlated (R-2 = 0.113) with %Fe-s, while the apparent relationship between %Fe-s and the calculated K-BB(+)/Fe ratio (R-2 = 0.888) and the V/Fe ratio (R-2 = 0.736) were observed, reflecting that %Fe-s could be controlled by both biomass burning and oil ash from ship emission, rather than mineral particles and coal fly ash, although the latter two are the main contributors to the atmospheric Fe loading during the sampling. Such information can be useful improving our understanding on iron solubility on East China, which may further correlate with iron bioavailability to the ocean, as well as human health effects associated with exposure to fine Fe-rich particles in densely populated metropolis in China. (C) 2014 Elsevier B.V. All rights reserved.