Biodiversidad de la calidad del agua mediante el estudio de macroinvertebrados acuáticos en el río San Pedro, cantón Rumiñahui, provincia Pichincha

Abstract

The San Pedro River that crosses several towns such as Cumbayá, Los Chillos, Amaguaña among other areas, is full of solid urban waste, sewage and bad odors, there are all kinds of discharges from agricultural, industrial and urban sectors, besides the expansion of the population of Sangolquí, Amaguaña and San Rafael is a considerable factor for the alteration of the ecosystem caused by pollution. The objective of this study is to determine the water quality of the San Pedro River by means of macroinvertebrates and compare the results with the ICA. Four sampling points were established depending on the altitude, these are: Algarrobos Park, San Pedro Boulevard, Balvina Park and Cachaco Park. Water quality was determined using the ICA by measuring nine parameters: pH, turbidity, temperature, dissolved oxygen, fecal coliforms, nitrates, phosphates, total dissolved solids, and BOD5. The BMWP/COL index was determined by sampling, separating, identifying and classifying the macroinvertebrates and assigning them a score according to the macroinvertebrate identification guidelines. The BMWP/COL index obtained a value of 22, being in class IV which indicates that the water quality is critical corresponding to very polluted waters, the presence of 1221 individuals was determined, and the predominant families are: Xiphocentronidae, Tubificidae and Glossiphoniidae, the ICA reaffirmed that water quality is poor. The point where the highest level of contamination was evidenced is in the Balvina Ecological Park with a score of 42.72 according to the ICA and 29 meaning that the type of water quality is critical and belongs to highly polluted waters.