Salminus hilarii, as a biological indicator in the Brazilian Cerrado

This study was conducted in dos Bois River, Araguaia-Tocantins basin, investigating the connections between physical and chemical conditions, fish diversity and well-being of Salminus hilarii in the Cerrado of northwestern Goiás. The research covered five sampling points, from upstream, before the waste from a mining company, to downstream, where it meets a tributary, in two stages: dry and rainy seasons. Dissolved oxygen, electrical conductivity, water and air temperatures, pH, BOD, COD, nitrogen series, phosphate series, fecal coliforms, chlorophyll-α and heavy metals were analyzed, according to Conama Resolution 357. The results show a relationship between the parameters analyzed and the effects on the organisms studied, with distinct data between upstream and downstream, linked to the proximity of agricultural and industrial areas. S. hilarii, through its morphological changes, evidences the intense exploitation of the Cerrado. The results suggest the need for priority actions to preserve biological diversity in the region.