Impactos cumulativos de hidrelétricas sobre a hidrologia e qualidade da água de um rio contribuinte do Pantanal

Abstract

The Paraguay River is the major tributary of the largest floodplain in the world, the Pantanal. Itsbasincontains five hydropower plants and fifty-eight small hydro power plants. In the Jauru River, an important tributary of the Paraguay River, a cascade of six hydropower plants was built along the longitudinal gradient of the river. The present study aimed at identifying and analyzing the impacts on the hydrology and water quality of the Jauru River caused by the cascade hydropower plants, considering not only the individual impact produced by each one but also the combination of their impacts together. We analyzed 12 parameters indicating water quality of the river, data from several sites along the longitudinal axis of the river, upstream and downstream of the reservoirs lakes. Also, 32 hydrological parameters were examined with the aid of the software IHA. Changes in hydrology and water quality were found after the installation of the hydropower plants. Our results question the assertion that small hydropower plants have little environmental impact on the river.