探讨川南城市群冬季重污染PM2.5中金属元素的浓度特征及来源(自贡,泸州,内江,和宜宾),于2018年12月30日至2019年1月14日采用膜采样方法测定PM2.5中的金属元素,并应用富集因子法(EF)和正矩阵分解法(PMF)对金属元素的来源进行调查.利用自贡市2015年同期的金属元素观测数据,考察了《中国大气污染防治行动计划》实施中后期自贡市金属元素污染和富集变化情况。主要研究结果如下:①不同城市颗粒物中金属元素的浓度和百分比差异不显著。四个城市中浓度较高的元素表现出相似性,Al,Sb,Fe在顶部。从自贡不同观测时期的比较来看,除Tl以外的所有元素的浓度发生变化。②富集因子计算结果表明,元素Cr的富集(自贡和宜宾),Ni,Cu,As,Se,Ag,Cd,Sb,Tl,城市群中铅较高。自贡不同观测时期元素富集水平的比较表明,除了铜,2018年冬季观察期呈下降趋势。③PMF来源分析结果表明,各城市的金属元素主要来源于粉尘源,燃煤来源,工业来源,和交通来源,而来源之间的贡献参差不齐。主要来源的贡献在城市之间有所不同,自贡以交通粉尘源和混合源为主,泸州以工业资源为主,内江有来自不同来源的类似贡献,宜宾以交通来源为主。
To investigate the concentration characteristics and sources of metal elements in PM2.5 during winter heavy pollution in the southern Sichuan urban agglomeration (Zigong, Luzhou, Neijiang, and Yibin), the metal elements in PM2.5 were measured using membrane sampling methods from December 30, 2018 to January 14, 2019, and the enrichment factor method (EF) and positive matrix factorization(PMF) were applied to investigate the sources of metal elements. The metal element observation data of Zigong in the same period of 2015 were also used to investigate the changes in metal element pollution and enrichment in Zigong in the middle and end of the implementation of China\'s Air Pollution Prevention and Control Action Plan. The main findings were as follows:① The concentrations and percentages of metal elements in particulate matter in different cities did not differ significantly. The elements with higher concentrations in the four cities showed similarities, with Al, Sb, and Fe at the top. From the comparison of different observation periods in Zigong, the concentrations of all elements except Tl changed. ② The results of the enrichment factor calculation showed that the enrichment of the elements Cr (Zigong and Yibin), Ni, Cu, As, Se, Ag, Cd, Sb, Tl, and Pb in the urban agglomeration was high. The comparison of the enrichment levels of elements in Zigong for different observation periods showed that the enrichment levels of all elements, except Cu, tended to decrease in the winter observation period of 2018. ③ The results of PMF source analysis showed that the metal elements in each city mainly originated from dust sources, coal-fired sources, industrial sources, and traffic sources, whereas there was a mixed contribution among the sources. The contribution of the main sources differed among cities, in which Zigong was dominated by traffic dust sources and mixed sources, Luzhou was dominated by industrial sources, Neijiang had a similar contribution from different sources, and Yibin was dominated by traffic sources.