Assessment of the water quality index of Amazon River using chemometrics method

Abstract

The objective of this work was to determine a water quality index (WQI), considering the spatial and seasonal variations of the Peixe-Boi River watershed using chemometrics methods. Twenty-eight sampling sites were selected. The elements Ag, Al, B, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Si, Ti, V, and Zn were determined using optical emission spectrometry with inductively activated plasma. (ICP-OES) and physicochemical parameters were evaluated using different techniques. The WQI values in the wet season indicated that 39.3 % of the samples collected had good quality and 60.7 % had excellent quality. In the dry season, the WQI values ranged from “Regular” (10.7 %), “Good” (67.9 %), and “Excellent” (21.4 %). The parameters evaluated were found, on average, by the standards of CONAMA resolution 357/2005 for class 2 freshwater rivers. The WQI are among the most effective ways of communicating water quality information to the public or quality managers.