Análisis Comparativo de Índices de Calidad del Agua Aplicados al Río Ranchería, La Guajira-Colombia

Abstract

This paper compares several water quality indices applied along 235.3 km of the river Ranchería, La Guajira-Colombia. The comparison directly adopts the values of the indices discretized in five equal intervals (raw indices), and, on their scoring, this is the environmental judgments (also in five classes) associated with such indices. The coincidence between couples of indices is analyzed, in both cases, through the correlation coefficient of Spearman and the Root Mean Square Error (RMSE). The results state that raw indices perform higher coincidence, better correlation and lesser deviations than do scorings. This fact stresses the weakness of the relation between the value of the indices and their qualification. It is necessary to carry out an inter-calibration exercise in order to consistently gear the different indices.