Análise qualitativa de poluentes na água das chuvas em Lavras - MG

Abstract

The objective of this study was to evaluate the dynamics of rainfall pollutants and nutrient input from rainfall in Lavras-MG in 2010-2011. Forty-one samples of rainfall were collected at two different points: downtown and at the Federal University of Lavras. Results of sampling showed average values, weighted by volume, of pH, alkalinity, carbonic acid, nitrate, ammonium and sulfate, respectively for samples collected downtown and at the Federal University of Lavras, equal to 6.5 and 6.9, 37.3 and 76.2 eq L-1, 173.0 and 133.6 eq L-1, 3.8 and 4.6 eq L-1, 21.2 and 16.7 eq L-1, 42.8 and 43.0 eq L1 . During this period there was an average contribution of 3.67 kg ha-1 NO3 - , 4.82 kg ha-1 NH4 + and 58.19 kg ha-1 SO4 2-. The highest concentrations of ammonium, sulphate and carbonic acid were found downtown, probably due to the greater contribution of pollution generated by automobiles. This contributes to the lower pH values observed downtown. However, the rainfall events in the region showed no immediate risk of environmental acidification.