Chemical characteristics of wet precipitation at Peradeniya in Sri Lanka

Abstract

The purpose of this research was to study chemical characteristics of precipitation in Peradeniya (Latitude 6.973701, Longitude 79.915256), Kandy District in Sri Lanka. This study was conducted during 2012 to 2014, and wet precipitation was analyzed for pH, conductivity, Na+, NH4+, K+, Mg2+, Ca2+, F−, Cl−, NO3−, SO42−, Pb, Cu, Mn, Al, Zn, and Fe for a total of 125 samples. Less than 2% events of acidic precipitation were recorded, and the VWA of the major ionic species present in precipitation samples were in the order of Ca2+ > Na+ > Cl− > NH4+ > SO42− > K+ > NO3− > Mg2+. Neutralization of acidity of precipitation is much more related to CaCO3 than NH3, and the presence of high content of Ca2+ strongly supports this fact. When considering marine contribution, SO42−/Na+, Ca2+/Na+, Mg2+/Na+, and K+/Na+ ratios are higher than the reference value suggesting that contribution of sources other than marine. Concentration of Zn is the highest while that of Mn is the lowest. Principal component analysis identified probable sources for major ionic and elemental sources as both natural and anthropogenic sources such as vehicular emission due to heavy traffic, waste incineration, bio mass burning, brass industry, and construction.