Environmental diagnosis of the watershed contributing to the tanque grande reservoir, Guarulhos (SP), based on benthic macroinvertebrates

Abstract

This research aimed to analyze the Tanque Grande reservoir water quality through the study of benthonic macroinvertebrates community structure. Two yearly collects of benthonic macroinvertebrates have been done on six collect points, once in the dry season (2017 August) and another one in the wet season (2017 December). The following environmental parameters have been studied: water temperature, pH, dissolved oxygen, water turbidity, electrical conductibility, total phosphorus, total nitrogen and E.coli. 1.516 organisms have been collected, registering the largest abundance of Chironomidade family (Diptera) in all the collect points and, most of all, degraded environmental parameters. This environmental degradation comes from the pisciculture and horticulture, as corroborated by the high concentrations of BOD and E.Coli in most of the analyzed points. It can be concluded that, although the studied environment is located in an area of environmental preservation, the "Environmental Protection Area Cabuçu Tanque Grande", shows signs of degradation, indicating the need of a more rigorous surveillance avoiding the progress of anthropic activities that are leading to environmental degradation.