Water Quality in Estero Salado of Guayaquil Using Three-Way Multivariate Methods of the STATIS Family

Abstract

Water property parameters were analyzed over 9 months across six stations within the Estero Salado. The parameters under evaluation included nitrite (NO2−), nitrate (NO3−), phosphate (PO43−), ammonium (NH4+), temperature, pH, biochemical oxygen demand (BOD), conductivity, salinity, color, turbidity, suspended solids, hardness, and alkalinity. Additionally, the TRIX index (which measures chlorophyll, oxygen saturation, nitrogen, and phosphorus) was considered. The multivariate technique employed was partial triadic analysis (PTA), a specialized variant developed from STATIS, enabling the examination of the common structure’s stability across months and the positioning of stations and variables within a compromise space. This analysis elucidated a variability of 69% and 96%, respectively. Stations could be characterized based on their associations with specific variables, while the analysis also facilitated the identification of months impacting the common structure of pollution indicators.