Gulson Brian, Korsch Michael, Dickson Bruce, Cohen David, Mizon Karen, Davis J Michael
Graduate School of the Environment, Macquarie University, Sydney NSW 2109, Australia.
Sci Total Environ. 2007 Aug 1;381(1-3):169-79. doi: 10.1016/j.scitotenv.2007.03.018. Epub 2007 May 1.
We have measured high precision lead isotopes in PM(2.5) particulates from a highly-trafficked site (Mascot) and rural site (Richmond) in the Sydney Basin, New South Wales, Australia to compare with isotopic data from total suspended particulates (TSP) from other sites in the Sydney Basin and evaluate relationships with source fingerprints obtained from multi-element PM(2.5) data. The isotopic data for the period 1998 to 2004 show seasonal peaks and troughs that are more pronounced in the rural site for the PM(2.5).samples but are consistent with the TSP. The Self Organising Map (SOM) method has been applied to the multi-element PM(2.5) data to evaluate its use in obtaining fingerprints for comparison with standard statistical procedures (ANSTO model). As seasonal effects are also significant for the multi-element data, the SOM modelling is reported as site and season dependent. At the Mascot site, the ANSTO model exhibits decreasing (206)Pb/(204)Pb ratios with increasing contributions of fingerprints for "secondary smoke" (industry), "soil", "smoke" and "seaspray". Similar patterns were shown by SOM winter fingerprints for both sites. At the rural site, there are large isotopic variations but for the majority of samples these are not associated with increased contributions from the main sources with the ANSTO model. For two winter sampling times, there are increased contributions from "secondary industry", "smoke", "soil" and seaspray with one time having a source or sources of Pb similar to that of Mascot. The only positive relationship between increasing (206)Pb/(204)Pb ratio and source contributions is found at the rural site using the SOM summer fingerprints, both of which show a significant contribution from sulphur. Several of the fingerprints using either model have significant contributions from black carbon (BC) and/or sulphur (S) that probably derive from diesel fuels and industrial sources. Increased contributions from sources with the SOM summer fingerprints could explain the summer-time peaks in isotopic ratio at both sites and, at the rural site, be associated with meteorological influences. Nevertheless, the SOM results indicate that there are multiple overlapping 'weak' sources.
我们已对澳大利亚新南威尔士州悉尼盆地一个交通繁忙地点（ Mascot ）和一个乡村地点（ Richmond ）的 PM(2.5) 颗粒物中的高精度铅同位素进行了测量，以便与悉尼盆地其他地点总悬浮颗粒物（ TSP ）的同位素数据进行比较，并评估与从多元素 PM(2.5) 数据获得的源指纹之间的关系。 1998 年至 2004 年期间的同位素数据显示出季节性峰值和谷值，对于 PM(2.5) 样本，这些峰值和谷值在乡村地点更为明显，但与 TSP 数据一致。自组织映射（ SOM ）方法已应用于多元素 PM(2.5) 数据，以评估其在获取指纹以与标准统计程序（ ANSTO 模型）进行比较方面的用途。由于季节性影响对多元素数据也很显著，因此 SOM 建模结果表明其与地点和季节有关。在 Mascot 地点，随着“二次烟雾”（工业）、“土壤”、“烟雾”和“海雾”指纹贡献的增加， ANSTO 模型显示出 (206)Pb/(204)Pb 比值下降。两个地点的 SOM 冬季指纹都显示出类似模式。在乡村地点，存在较大的同位素变化，但对于大多数样本而言，这些变化与 ANSTO 模型中主要源的贡献增加无关。在两个冬季采样时段，“二次工业”、“烟雾”、“土壤”和海雾的贡献增加，其中一个时段的铅源与 Mascot 地点的铅源相似。使用 SOM 夏季指纹在乡村地点发现 (206)Pb/(204)Pb 比值增加与源贡献之间仅存在正相关关系，两者均显示出硫的显著贡献。使用任一模型的几个指纹都有来自黑碳（ BC ）和 / 或硫（ S ）的显著贡献，这些可能来自柴油燃料和工业源。 SOM 夏季指纹中源贡献的增加可以解释两个地点同位素比值的夏季峰值，并且在乡村地点，这与气象影响有关。然而， SOM 结果表明存在多个重叠的“弱”源。
