| Abstrakt: |
This study focused on the characteristics, distribution, and source of inorganic ions in segmented precipitation of Nanchang. The method of segmented collection of precipitation samples, previously established by our research group, was adopted. From May to September 2020, 20 precipitation events were investigated. A total of 88 segmented precipitation samples were collected, and Na+, NH4+, K+, Mg2+, Ca2+, Cl−, NO2−, NO3−, and SO42− were determined. The concentrations of these ions in segmented precipitation samples decreased generally from the first to the sub-last segment and frequently increased from the sub-last to the last segment, indicating that the ions of the early segmented precipitation were mainly derived from air pollutants and those of the last segmented precipitation from cloud water and washed condensed particles. Both Ca2+ and NH4+ were dominant cations, whereas NO3− and SO42− were the dominant anions. The concentrations of Ca2+, NH4+, NO3−, and SO42− in precipitation of Nanchang were medium, reflecting moderate air pollution. The correlations between two of Na+, NH4+, K+, Cl−, NO2−, NO3−, and SO42− in the first two segmented precipitation samples were slightly weaker than those in the last two segmented precipitation samples, indicating contribution both from below-cloud and in-cloud scavenging in early precipitation and from cloud water in late precipitation. The contribution of below-cloud scavenging to major ions in precipitation decreased gradually, and conversely, the contribution of in-cloud scavenging to ions in precipitation increased gradually. [ABSTRACT FROM AUTHOR] |
Full text from SpringerLink