Quimiometria aplicada à avaliação química do igarapé que cruza o polo industrial de Manaus/AM

Abstract

The Quarenta stream is an important body of water that crosses the city of Manaus, in the Amazon. For a long time, this water body represented sources of leisure and landscaping for the region. However, today it represents an open-air dump in the middle of the city of Manaus. The aim of this study was to evaluate environmental variables of the waters of the Forty stream using chemometry, from HCA and PCA at five points in the Quarenta stream that cross the Manaus industrial pole. The results led to high levels of ammonium, much higher than allowed and with high rates of metals Fe and Mn. The pH of the water is altered in at least two units, going from acid to basic in three decades and the electrical conductivity values are at least five times above the natural. HCA showed important associations between ammonium and pH, which suggests that this ion may be the buffering agent of these degraded waters. Another important association was observed between electrical conductivity and HCO3-. The PCA confirmed this last association and showed that the alkalinity expressed in HCO3- may be the most sensitive variable in the data set, implying that electrical conductivity can be increased by increasing alkalinity.