Formulación de un índice de calidad de aguas para cuencas rurales en zonas de montaña basado en un estudio de subcuencas de la microcuenca Doña María del valle de Aburrá

Abstract

This research addresses the formulation of a water quality index for rural mountain basins, emphasizing the use for ecological functions and maintenance of aquatic life. It included the construction of the weighting factors (Pi) and quality sub-indices for each parameter (Qi), as well as the determination of the really incident variables in this type of basins, based on the information generated in 18 rural and mountain micro basins, tributaries of the Doña María micro basin, the main tributary of the Aburrá River, in Antioquia (Colombia). The research was based on data from two main sources: a. field data taken in different monitoring campaigns, under the coordination of the author, with historical data from 2007 to 2017, and b. new information generated during the investigation, including an extensive review of bibliographic sources. In total, about 65 monitoring sites and more than 20 parameters are considered. More than 500 equation versions, both empirical and statistical, were tested (adjusting the quality values -Qi- and the weighting values -Pi-) and contrasted with the biological quality values (BMWP / Col), which served as adjustment to the water quality index for rural mountain basins (ICACRM). Likewise, the index was validated in 59 sites of 18 microbasins and finally it was compared with other international indexes frequently used in Colombia and Latin America, showing better results in terms of adjustment. The main results are the construction of parametric curves for each variable included in the index, adjusted to the conditions of rural mountain basins; the definition of the weighting values applied to this type of basins; the rating tables and the formulation of the index itself. The results contribute an important advance to the service of research centers and public institutions of the Aburrá Valley and Antioquia. The IDEAM and the CARs are proposed to test the index in the rest of the country. Likewise, it is fundamental in the implementation of the Local Environmental Observatory of San Antonio de Prado, which develops environmental monitoring in different fields. This is the only observatory led by community and research organizations in the Aburrá river basin. This model can be replicated, by social organizations, in other territories and municipalities of the basin, the department and perhaps the country that have similar environmental conditions.