Significant contribution of spring northwest transport to volatile organic compounds in Beijing

• 作者: Dan Yao Guiqian Tang Yinghong Wang Yuan Yang Lili Wang Tianzeng Chen Hong He Yuesi Wang
• 来源期刊: 环境科学学报（英文版）
• 年，卷（期）: 2021,（6）
• 页码范围: 169-181
• 页数: 13页
• 语种: 英文

摘要

High values of ozone(O3)occur frequently in the dry spring season;thus,understanding The evolution characteristics of volatile organic compounds(VOCs)in spring is of great sig-nificance for preventing O3 pollution.In this study,a total of 101 VOCs from April 16 to May 21,2019,were quantified using an online gas chromatography mass spectrometer/flame ionization detector(GCMS/FID).The results indicated that the observed concentration of Total VOCS(OVOCs)(17.4％),halocarbons(12.7％),aromatics(9.5％),alkenes(8.2％),Acetylene(5.3％)and carbon disulfide(2.5％).The average mixing ratio of VOCs showed obvious diurnal variation(high at night,low during daytime),We conducted a source ap-portionment study based on 32 major VOCs using positive matrix factorization(PMF),and coal+biomass burning(25.2％),diesel exhaust(16.0％),gasoline exhaust+evaporation(17.4％),secondary+long-lived species(16.7％),biogenic source(4.3％),industrial emissions(9.3％)and solvent use(11.2％)were identified as major sources of VOCs.In addition to lo-cal emission,most of the atmospheric VOCs were derived from long-distance air masses(65.7％)and the average mixing ratio of VOCs in the northwest direction was 29.4 ppbv.Combined with the results of the potential source contribution function(PSCF)indicate that research should focus on the local emissions of combustion transportation sources and sol-vents usage to control atmospheric VOCs.Additionally,transmission of the northwest air mass is an important component that cannot be ignored during spring in Beijing.