Trend in chemical composition of precipitation during 2005–2009 at a rural station of Bhubaneswar, eastern India

Abstract

Precipitation samples collected during 2005- 2009 from a rural forest station of Bhubaneswar were ana- lyzed for their chemical composition. The samples were collected through a wet-only (WO) collector and two bulk (B1 and B2) collectors. The ions were evenly balanced indicating good data quality. The overall pH of rainwater was slightly acidic and ~47% of all rain events during the period were acidic (pH<5.6). Multilinear regression analy- sis showed relation between the free acidity (H + ) and other components in rainwater. Enrichment factors (EF) of the major components with respect to their sources such as marine and crustal were calculated. Maximum EF was ob- served for NO3 � for both marine and crustal sources for all the three collectors. Source apportionments were also car- ried for the ions. Trend analysis showed continuous increase in most of the ions over years during the study period driven by anthropogenic emissions. Statistical/factorial analysis established correlation among different ions.