AVALIAÇÃO DA QUALIDADE DO MEIO AQUÁTICO NA BACIA DO RIO MEIA PONTE, ALTO RIO PARANÁ, UTILIZANDO O ÍNDICE BASEADO NO PEIXE (IBP) COM DIFERENTES CRITÉRIOS DE PONTUAÇÃO.

Abstract

The Meia Ponte River basin is known not only for being major source of water supply for the city of Goiânia and other regions of the Goiás State, but also by the intense anthropogenic pressure resulting from the multiple use of their terrestrial environment. This study aims to evaluate the quality of the aquatic environment of this basin, through the Fish Based Index (FBI) using different scoring criteria. The data used was extracted from the database of the Center for Aquatic Biology - Pontifícia Universidade Católica de Goiás, which is composed by samplings in 30 tributaries performed between March and August 2001 and at five stations in the main channel during May, November and December 2006. From a total of 58 fish assemblages descriptors and 20 quantitative and qualitative environmental variables selected a priori to characterize the biotic integrity, 16 descriptors (abundance, abundance of the families Characidae, Crenuchidae, Lebiasinidae, Loricariidae, Pimelodidae, Poecilidae and Prochilodontidae, family richness of Crenuchidae and Pimelodidae, trophic guild richness of herbivores, insectivores and piscivores, abundance of detritivores and insectivores) and 9 qualitative environmental variables showed statistically significant variations, compounding the FBI, which in turn was scored using different valuation models. Overall, it is observed a low quality of the aquatic environment in the tributaries or the main channel of the Meia Ponte River basin. It is expected that this index may contribute to the regional monitoring of environmental quality and thus become a management tool of freshwater ecosystems by the control agency.