Yale-NUIST Center on Atmospheric Environment, International Joint Laboratory on Climate and Environment Change, Nanjing University of Information Science and Technology, Nanjing 210044, China.
Key Laboratory Meteorological Disaster; Ministry of Education & Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster, Nanjing University of Information Science and Technology, Nanjing 210044, China.
Environ Sci Technol. 2022 Apr 5;56(7):3905-3914. doi: 10.1021/acs.est.1c05823. Epub 2022 Mar 16.
Sulfate (SO) is a major species in atmospheric fine particles (PM), inducing haze formation and influencing Earth's climate. In this study, the δS values in PM sulfate (δS-SO) were measured in Hangzhou, east China, from 2015 September to 2016 October. The result showed that the δS-SO values varied from 1.6 to 6.4‰ with the higher values in the winter. The estimated fractionation factor (αS) from SO to SO averaged at 3.9 ± 1.6‰. The higher αS values in the winter were mainly attributed to the decrease of ambient temperature. We further compared the quantified source apportionments of sulfate by isotope techniques with and without the consideration of fractionation factors. The result revealed that the partitioned emission sources to sulfate with the consideration of the fractionation effects were more logical, highlighting that fractionation effects should be considered in partitioning emission sources to sulfate using sulfur isotope techniques. With considering the fractionation effects, coal burning was the dominant source to sulfate (85.5%), followed by traffic emissions (12.8%) and oil combustion (1.7%). However, the coal combustion for residential heating contributed only 0.9% to sulfate on an annual basis in this megacity.
硫酸盐（SO）是大气细颗粒物（PM）中的主要物质，它会导致雾霾的形成并影响地球的气候。本研究于 2015 年 9 月至 2016 年 10 月在中国东部的杭州测量了 PM 中硫酸盐的δS 值（δS-SO）。结果表明，δS-SO 值的变化范围为 1.6‰至 6.4‰，冬季的值较高。从 SO 到 SO 的平均分馏因子（αS）为 3.9±1.6‰。冬季较高的αS 值主要归因于环境温度的降低。我们进一步比较了同位素技术定量源分配的硫酸盐与不考虑分馏因子的情况。结果表明，考虑分馏效应的硫酸盐分配排放源更为合理，突出表明在使用硫同位素技术分配硫酸盐的排放源时应考虑分馏效应。考虑分馏效应后，燃煤是硫酸盐的主要来源（85.5%），其次是交通排放（12.8%）和石油燃烧（1.7%）。然而，在这个特大城市中，燃煤取暖对硫酸盐的年贡献仅为 0.9%。
