Influencia del uso y cobertura de suelo en la calidad del agua de la Laguna San Martín ubicada en la parroquia San Gerardo, cantón Girón de la provincia del Azuay

Abstract

The influence of land use and land cover on the water quality of the San Martín lagoon located in the Girón canton was investigated. Five water monitors were made; samples were taken at five points in the lagoon and one in the stream that feeds it. Seventeen physical, chemical and microbiological parameters were analyzed and the results determined the quality of the lagoon's water regarding for livestock, irrigation and recreational purposes in accordance with the limits established in Annex I, Book VI of the TULSMA. A zone of influence of 241.95 ha was established around the lagoon, where land use and land cover were classified. Subsequently, Spearman's correlation method was applied to determine the relationship between water quality parameters, obtaining strong positive and negative correlations, including chlorides respect to phosphates of 0.953 and BOD5 with alkalinity of -0.507. To find the relationship between land use and land cover respect to water quality parameters, a Pearson correlation was applied, which showed that natural areas had a negative correlation with most pollutants, other land uses such as livestock had a negative impact, and low-density pasture had a mixed impact in the study area. Finally, it was established that the water quality of the lagoon is in a medium-high contamination range.