Seasonal variations, temperature dependence, and sources of size-resolved PM components in Nanjing, east China

作     者：Mingjie Xie Wei Feng Shuyan He Qin’geng Wang Mingjie Xie;Wei Feng;Shuyan He;Qin'geng Wang

作者机构：Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologyJiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution ControlSchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjing 210044China State Key Laboratory of Pollution Control and Resources ReuseSchool of the EnvironmentNanjing UniversityNanjing 210023China 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2022年第34卷第11期

页      面：175-186页

核心收录：

学科分类：07[理学] 070602[理学-大气物理学与大气环境] 0706[理学-大气科学] 0714[理学-统计学（可授理学、经济学学位）] 0703[理学-化学] 0701[理学-数学] 

基　　金：supported by the National Key Research and Development Program of China (No. 2016YFC0208504) the National Natural Science Foundation of China (Nos. 42177211, 41701551)。 

主　　题：Particulate matter Size distribution Seasonal variation Semi-volatility Source apportionment 

摘      要：Size-segregated ambient particulate matter(PM) samples were collected seasonally in suburban Nanjing of east China from 2016 to 2017 and chemically speciated. In both fine( 2.1 μm, PM2.1) PM, organic carbon(OC) accounted for the highest fractions(26.9% ± 10.9% and 23.1% ± 9.35%) of all measured species, and NO3-lead in average concentrations of water-soluble inorganic ions(WSIIs). The size distributions of measured components were parameterized using geometric mean diameter(GMD). GMD values of NO_(3)^(-), Cl^(-), OC, and PM for the whole size range varied from 2.1μm in warm seasons, which was due to the fact that the size distributions of semi-volatile components(e.g., NH4NO3, NH4Cl, and OC) had a dependency on the ambient temperature.Unlike OC, elemental carbon(EC), and elements, NH_(4)^(+), NO_(3)^(-), and SO_(4)^(2-)exhibited an increase trend in GMD values with relative humidity, indicating that the hygroscopic growth might also play a role in driving seasonal changes of PM size distributions. Positive matrix factorization was performed using compositional data of fine and coarse particles, respectively. The secondary formation of inorganic salts contributing to the majority( 70%) of fine PM and 20.2% ± 19.9% of speciated coarse PM. The remaining coarse PM content was attributed to a variety of dust sources. Considering that coarse and fine PM had comparable mass concentrations, more attention should be paid to local dust emissions in future air quality plans.