Abstract:
Acid rain is one of the major problems in the world. It is increasing day by day due to rapid urbanization and rapid industrialization. Recently, acid rain problems have also extended to Asia, because of significant increase in atmospheric emissions resulting from industries and automobiles. Therefore, it is important that acid-rain monitoring be conducted in Urban and rural areas. If the pH of the rainwater is less than 5.6 then it is said to be Acid rain. Bulk precipitation samples were collected at Hebbal, an Industrial belt of Bangalore using bulk precipitator collectors. The samples were collected during south-west monsoon 2005 and 2006. Concentration of major cations and anions were determined and predominant ions were identified. Concentration of major cat ions (H, Ca2+, Mg2+, Na,
K and NH4+ — N) and anions (cr, Hco3, NO2-, NO3 and P043- P) were determined. The study showed that the bulk precipitation at Hebbal industrial belt was towards acidic range. The statistical data clearly established that highly significant positive correlation coefficient between Fr and S042- and also between 1-1+ and NO3- indicating the decreasing trend of pH. The Ca2+ and NH4 were acting as neutralizing ions. The decreasing trend of pH in the bulk precipitation may be attributed to local emissions of SO2 and NOx from urban activities.