摘要
The characteristics of water-soluble ions in size-resolved particulate matter were investigated usingion chromatography at Shangdianzi, a regional background station of Beijing, Tianjin, and Hebei. Seasonal total concentrations of ions (Na+, Mg2+, IC, Ca2+, NH+4, Cl-, SO2-4 and NO-3) were 75.5 ± 52.9 μg/m3 in spring, 26.5 ± 12.3 Bg/m3 in summer, 22.7 ± 20.4 μg/m3 in autumn, and 31.1 ± 23.9 μg/m3 in winter, respectively. The secondary ions (NO3, SO2-4 and NH+4), mainly associated with fine particles, accounted for 84.2% in spring, 82.1% in summer, 81.5% in autumn and 76.3% in winter of all ions. Strong correlations were found between NH+4 and SO2-4 (r = 0.95, p 〈 0.01) as well as NH+4 and NO-3 (r = 0.90, p 〈 0.01) in fine particles; while in coarse particles, correlations between Mg2+ and NO-3 (r = 0.80, p 〈 0.01), and Ca2+ and NO2+ (r = 0.85, p 〈 0.01) were found. The concentrations of Na+, IC, Mg2+, Ca2+, NH+4, Cl-, NO3, and SC2-4 were 2.02, 0.81, 0.36, 1.65, 9.58, 4.01, 18.9, and 18.4 μg/m3 in particulate matter from southeast-derived air masses, which were typically 1.58-3.37 times higher than in northwest trajectories. Thus, concentrations of water-soluble ions at this background station were heavily influenced by regional transport of serious pollution derived from biomass burning, coal combustion, industrial and vehicle exhaust emissions from Beijing, Tianjin, and Hebei.
The characteristics of water-soluble ions in size-resolved particulate matter were investigated usingion chromatography at Shangdianzi, a regional background station of Beijing, Tianjin, and Hebei. Seasonal total concentrations of ions (Na+, Mg2+, IC, Ca2+, NH+4, Cl-, SO2-4 and NO-3) were 75.5 ± 52.9 μg/m3 in spring, 26.5 ± 12.3 Bg/m3 in summer, 22.7 ± 20.4 μg/m3 in autumn, and 31.1 ± 23.9 μg/m3 in winter, respectively. The secondary ions (NO3, SO2-4 and NH+4), mainly associated with fine particles, accounted for 84.2% in spring, 82.1% in summer, 81.5% in autumn and 76.3% in winter of all ions. Strong correlations were found between NH+4 and SO2-4 (r = 0.95, p 〈 0.01) as well as NH+4 and NO-3 (r = 0.90, p 〈 0.01) in fine particles; while in coarse particles, correlations between Mg2+ and NO-3 (r = 0.80, p 〈 0.01), and Ca2+ and NO2+ (r = 0.85, p 〈 0.01) were found. The concentrations of Na+, IC, Mg2+, Ca2+, NH+4, Cl-, NO3, and SC2-4 were 2.02, 0.81, 0.36, 1.65, 9.58, 4.01, 18.9, and 18.4 μg/m3 in particulate matter from southeast-derived air masses, which were typically 1.58-3.37 times higher than in northwest trajectories. Thus, concentrations of water-soluble ions at this background station were heavily influenced by regional transport of serious pollution derived from biomass burning, coal combustion, industrial and vehicle exhaust emissions from Beijing, Tianjin, and Hebei.
基金
supported by the National Environmental Protection Commonweal Research Project(No.201509062 and No.201409073)
the National Natural Science Foundation of China(No.41105089)
Research Project of Environmental Development Cenre(No.DY-2016-5)
State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences(No.SKLECRA201637)