Study on the impact of biomass combustion on PM2.5 in Zhejiang based on tracer monitoring
Atmospheric fine particulate matter(PM2.5)samples were collected simultaneously from 11 cities in Zhejiang from September 2019 to August 2020.The concentrations of levoglucosan(LG)and K+,two typical tracers of biomass burning,in PM2.5 were measured to analyze the impact of biomass burning on PM2.5.The results showed that the annual average mass concentration of LG in Zhejiang was 43.3 ng/m3.The seasonal average concentrations of LG were winter＞spring＞autumn＞summer,with higher concentrations in Quzhou and Lishui,and the lowest concentration in the island city of Zhoushan.The concentration of LG had the strongest correlation with temperature;LG concentrations were lower when the temperature was above 25 ℃ and higher when the temperature was below 18 ℃.When the temperature was between 18-25 ℃,LG concentrations were significantly influenced by relative humidity,with a marked decrease when the relative humidity exceeded 90％.The LG/K+ratios of most samples were less than 1,indicating that biomass burning in Zhejiang primarily consisted of crop residue combustion.Based on the simplified tracer model estimation,the average contribution of biomass burning sources to organic carbon(OC)in PM2.5 of Zhejiang was 8.5％,with a contribution rate as high as 16.3％in winter.The research findings would provide decision support for the formulation of PM2.5 pollution prevention and control measures in Zhejiang.
biomass combustionlevoglucosanspatial and temporal distributionmeteorological parametersK+organic carbonZhejiang
万方数据
维普
