Chemical Clasification of the Water in a Lowland River Basin (Salado River, Buenos Aires, Argentina) Affected by Hydraulic Modifications

Chemical classification of the water in a lowland river basin of Argentina, affected by hydraulic modification, was presented. Calcium concentration was determined by the EDTA titrimetric method and magnesium by calculation. Principal Component Analysis (PCA) was carried out from a correlation matrix and for the best graphic representation of the cases the axes were rescaled using standard deviation multiplication. The water of the Salado River and its tributaries were alkaline, with a mean pH of 8.63 and mean total dissolved solids (TDS) value reached 2 691 mg/l. The main cation in the basin was Na super(+), with a similar concentration at all sampling stations located in the main river course but with differences in the tributaries.