Benthonic macroinvertebrates as indicators of environmental quality in river confluences in the central-south of Paraná

Abstract

Benthic macroinvertebrates are considered bioindicators of environmental quality, since their presence, diversity and abundance in aquatic ecosystems reflect the interaction between environmental conditions, water and sediment quality, in addition to the degree of impact of human activities and tributaries in the river system. The objective of this work was to evaluate the environmental quality in three river confluences in different domains of land use and occupation, in the municipality of Guarapuava, Paraná (Brazil), based on benthic communities, using the BMWP
index and the Rapid Protocol of Assessment (PAR). Three river confluences representing different land uses were chosen: industrial, agricultural and natural tree vegetation. Aquatic macroinvertebrates were collected by scavenging in three sections of the confluences, downstream and upstream of the river junction in the main river and the tributary. In total, 205 individuals were collected, distributed across 15 taxa belonging to two classes and one phylum. Among the taxa collected, eleven belong to the class Insecta, three to Mollusca and one to the phylum Platyhelminthes. It is concluded that the use of benthic macroinvertebrates, as indicators of environmental quality, reflected the influence of anthropogenic actions of land use and occupation and hydrological dynamics on the structure of the community.