Physicochemical Characteristics Of Atmospheric PM₁₀and PM_2.5in Fuzhou

Water-soluble ions and metallic element pollutants of particulate matter were the main form of urban air pollution.The study of atmospheric physicochemical characteristics such as water-soluble ions and metal element was useful for relevant departments to make air pollution control measures,and was meaningful for urban residents to improve their quality of life.Different samples in PM2.5 and PM1O in Fuzhou environmental monitoring Station and radiation environment Station were collected during December 2016 to October 2017,physical and chemical characteristics of atmospheric particulate matter were analyzed.We used Ion Chromatography(IC)and Inductively Coupled Plasma Mass Spectrometry(ICP-MS)to measure the concentration of water-soluble inorganic ions and metal elements,after that,temporal and spatial variation rule and composition characteristics could be concluded.Relativity analysis and factor analysis(FA)methods were used to understand the correlation between different ions and its sources apportionment.Enrichment factor(EF)method was used to understand the sources apportionment of metal.Morphology of single particulate matter in busy traffic junction was observed by scanning electron microscope(SEM).The results indicated that:(1)The mass concentration of particulate matters in winter and spring were higher than that in summer and autumn.During the period of monitoring,97.44%of these days could reach the National average daily quality standard for grade two in PM2.5,100%of these days could reach the National average daily quality standard for grade two in PM1O.The mainly types of single particulate matter in traffic junction in Fuzhou were soot,mineral particles and organic particles,and the size range was usually below 2m.(2)SO42-,N03-,NH4+ were the main components of water-soluble ions of atmospheric particulate in Fuzhou,which was accounted for 78.93%and 73.54%in PMIO and PM2.5 respectively.The water-soluble ions concentration was high in December 2016 and May 2017 and low in July and October 2017.Water-soluble inorganic ions in PM2.5 in Fuzhou was mainly affected by biomass burning,fossil fuel combustion,diesel combustion,dust and industrial emission;water-soluble inorganic ions in PM1o in Fuzhou was mainly affected by biomass burning,fossil fuel combustion,diesel combustion and dust.(3)Mn,Pb,Cu,Cr,As,Ti,V were the main elements in Fuzhou,Mn and Ni were existed in coarse particles while others were almost existed in fine particles.The metal elements concentration was highest in December 2016,and had the lowest value in October 2017 in both PM1o and PM2.5.Enrichment factor methods indicated that Cd revealed the most serious degree of enrichment,a conclusion could be concluded that V,Cr,Mn,Ni,Cu,As,Cd,Pb came from anthropogenic pollution.Fuzhou was mainly affected by traffic emission,coal burning,fuel burning and waste incineration.