Determination of Ra-226 e Pb-210 in sedimet cores from Pirapora do Bom Jesus and Salto de Itu reservoirs: state of São Paulo

Abstract

The Tiete River drains an area composed of six sub-basins (Alto Tiete, Sorocaba/Médio Tiete, Piracicaba-Capivari -Jundiai, Tiete/Batalha, Tiete/Jacaré and Baixo Tiete). Along its extension (1100 km), there are 62 municipalities. In spite of all its historical contribution, hydroelectric potential and being one of the most economically important rivers in the state of São Paulo, the Tiete river is also one of the world's most polluted rivers, especially in the municipality of the city of São Paulo. As a result of pollution problems observed in the last few decades, a project was established to evaluate the concentration of metals, major and trace elements in surface and core sediment samples, in points from its source in Salesopolis until to the end, Parana River. The sediment cores will be collected in the main reservoirs formed by the water dam of Tietê River. The objectives of this work are to determine the sedimentation rate and the ages of the sediments using the Pb-210 dating method and with other results, like the chemical composition of the sediments, evaluate the environmental impact caused by the land uses. For a better understand of the results obtained factorial analysis, cluster analysis and principal component analysis will be applied.