Assessment of water quality in the Alambrado River using benthic macroinvertebrates as bioindicators in Laguna de la Mica Reservoir

Abstract

The water quality of the Alambrado River was evaluated using benthic macroinvertebrates and physical-chemical parameters. The following indices were measured: Multimetric Index of the Ecological Status of High Andean Rivers (IMEERA), Ephemeroptera, Plecoptera, and Trichoptera Index (EPT), Andean Biotic Index (ABI), and the pilot index Biological Monitoring working party / Ecuador (BMWP/ECU), Principal Component Analysis (PCA) and Canonical Correspondence Analysis (ACC), during three months (January to March 2019). 1993 individuals were collected; the Chironomidae family was the most abundant (80%), and the lesser abundant were Gerridae, Simulidae, and Leptoceridae (0.05%). More than 90% were collector’s macroinvertebrates. PCA and ACC determined that total suspended solids had a more significant relationship with most taxa collected. Water quality was determined to be between bad to moderate, and the biological indices used were sensitive to dissolved oxygen, biochemical oxygen demand (DBO5), chemical oxygen demand (DQO). These parameters vary according to the climatic season.