Estabelecimento dos valores de referência de qualidade para a Bacia do Rio Sirinhaém

Abstract

The establishment of geochemical reference values is indispensable for determining the current state of soil contamination. However, there is a need to estimate these values for several Brazilian river basins and there is still no scientific consensus on the methodology for their determination. In this context, this study aimed to establish the reference geochemical values in the Sirinhaém river basin through the integrated method that uses direct and indirect analyzes to identify the most appropriate calculation methodology. Soil samples were collected in preservation areas of the Sirinhaém river basin, PE, Brazil. The elements Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Zn present in soil samples were quantified by flame atomic absorption spectrometry. Due to the lack of normal distribution and independence, nonparametric statistical methods based on the third quartile were applied to establish geochemical reference values. The soil metal contents of the Sirinhaém river basin followed the following ascending order: Cd, Co, Mg, Cr, Ni, Cu, Mn, Pb, Zn, Ba, Fe e Al. The present study showed that The use of samples from conserved watershed areas is an effective source for establishing soil quality reference values.