ZHANG Yanmei, LI Jinjuan*, ZHANG Wei, LIU Xiaochun, YANG Huini

(College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550003, China)

Abstract: Atmospheric PM10 samples were collected in Qingyang District of Chengdu City, China under the weather of one serious haze in January 10-19, 2015. Mass concentrations and components of 9 water-soluble ions（Cl-, F-, NO3-, SO42-, NH4+, Mg2+, Ca2+, Na+, and K+）in PM10 were analyzed. Results indicate that the average concentration of PM10 in the haze days reaches 357.8 μg/m3; total concentrations of water-soluble ions in the haze days are higher than those of normal days; secondary inorganic ions (NO3-, SO42-, and NH4+) account for over 74.53% of the total water soluble ions. Mass concentrations, mass fractions and ion ratios of the water-soluble ions in haze and normal days reflect that the haze is caused by motor vehicle emissions, coal combustion, building operations and meteorological factors. Ratios of NO3-/SO42- in PM10 range from 0.7551 to 1.410, and the average ratio is 1.050, demonstrating that Chengdu City is under combined contamination of coal combustion and motor vehicles. Among all PM10 samples, NH4+ shows good correlation with NO3- and SO42-, so does NO3- with SO42-. Correlation coefficients of NH4+with NO3- and SO42-were 0.8450 and 0.9660, respectively. The NH4+, NO3- and SO42- mainly exist as (NH4)2 SO4 and NH4 NO3 in PM10, and the correlation coefficient between Ca2+ and Mg2+is 0.9130.

Keywords:Chengdu City; PM10; water-soluble ion; air pollution; haze

EARTH AND ENVIRONMENT Vol. 44, No.2 Tot No.310, 2016, Page 219-224