Atmospheric quality through analysis of dry and wet deposition at selected locations in Kandy and Gampaha districts of Sri Lanka

The objective of the study was to quantitatively determine rainwater quality parameters, using standard procedures, in selected areas of Sri Lanka. Analysis of weekly sampling of bulk deposition in three sampling sites in Divulapitiya, Kandy, and University of Peradeniya (UOP) of Sri Lanka performed for a period of 24  weeks from 08th of February 2022 to 19th of July 2022 indicated that the three sites had 16.7%, 8.7%, and 8.3% dry-only depositions, respectively; with rainfall levels of 30.2 ± 37.4 mm, 30.6 ± 32.6 mm, and 33.7 ± 39.8 mm; and volume-weighted mean (VWM) pH values of 6.23, 6.29, a nd 6.47, respectively. Acidic deposition events below pH 5.60 level were not recorded from any site. Chloride (Cl−) was determined to be the predominant anion, and the VWM of anions varied in the order of NO3− <  SO42 − <  Cl− in all three sites. Among trace metals investigated, Fe, Zn, and Al were predominant. Moreover, a very strong positive correlation for conductivity, total dissolved solids, and salinity among each parameter, was observed in the Pearson correlation analysis for all sites. Divulapitiya area showed low air pollution levels with respect to chemical and physical parameters determined in the study as compared to Kandy and UOP areas. Possible causes for the results would be vehicular, constructional, and industrial emissions, and natural geographical factors.
Source: Air Quality, Atmosphere and Health - Category: Environmental Health Source Type: research