Análisis de presencia y distribución de macro invertebrados bentónicos, indicadores de calidad de agua en ambientes fluviales

Abstract

This study aimed to survey the benthic macroinvertebrate, to analyze their composition, distribution and abundance, to characterize the water quality in Teusacá River using the Family Biotic Index (FBI) and their correlation with five chemical parameters. 10 sites were georeferenced and established on the study area and two samples were taken: one at the end of a dry season and another at the end of a rainy season. Three Macroinvertebrates samples and a litre water sample per each site were collected. Water samples for the following parameters: total organic carbon, nitrites, nitrates, sulphates and phosphates were analyzed at a certified laboratory. The following metrics were estimated: taxa composition, abundance, tolerance, Family Biotic Index, Margalef Index, Shannon-Weaver Index and Pielou Index. The FBI values for the water quality were consistent with those reported in the chemical analysis. Total organic carbon and phosphates presented very high values in the water of sites with fair, fairly poor, poor and very poor water quality; while the nitrites, nitrates and sulfates maintained their values well below the allowable values for human consumption in all sampling. These results suggested high level of anthropogenic impact in the subbasin and the main pollutants were the total organic carbon and phosphates.