Temporal Distribution and Source Apportionment of Composition of Ambient PM2.5 in Urumqi, North-West China

In order to identify the pollution characteristics and sources of PM2.5 in Urumqi, fine particulate matter samples were collected from September 2017 August 2018, water-soluble ions (WSIs), organic carbon (OC), elemental (EC), polycyclic aromatic hydrocarbons (PAHs), metal elements analyzed. The results indicate that annual mass concentration Urumqi was 158.85 ± 15.11 ?g/m3, with highest seasonal average autumn (180.49 87.22 ?g/m3) lowest summer (148.41 52.60 ?g/m3). SO42? (13.58 16.4 ?g/m3), NO3? (13.46 17.5 NH4+ (10.88 12.2 most abundant WSIs, secondary inorganic (SNA = + NH4+) accounted for 87.23% WSIs. NO3?/SO42? ratio indicates contribution stationary dominant. concentrations OC EC 12.00 4.4 µg/m3 5.00 3.5 µg/m3, respectively, OC/EC ratios winter (2.55 0.7), spring (3.43 1.3), (3.22 1.1) greater than 2, there formation (SOC). correlation between (R2 0.53) low. PM2.5, Al Fe elements. season occurred autumn, 10.1 8.33 6.9 respectively. enrichment factor (EF) shows come natural sources, Cd element mainly comes anthropogenic sources. PAHs a middle molecular weight main ones, 451.35 ng/m3. positive matrix model (PMF) source analysis are five including crustal minerals, biomass combustion, coal vehicular transport, aerosols. distribution percentages these different 19.2%, 10.2%, 12.1%, 8.2%, 50.3%,