PRESENCE AND ABUNDANCE OF PUBLIC INTEREST BACTERIA IN SEDIMENTS from THE UPPER COMPARTMENTS OF BARRA BONITAS RESERVOIRs, SÃO PAULO - brazil (Tietê AND Piracicaba RIVERS)

Resumo

Barra Bonita’s reservoiris in a highly dense demographic region, and receives high loads of sewage daily in naturawhich are transported mainly by the Piracicaba and Tietê rivers. This fact has provoked the available hydric resources commitmentfor both human consumption and plantation irrigations thus increasing considerably the risk of waterborne diseases. It is known that high densities of fecal originated microorganisms accumulate among the sediments in the deeper parts of aquatic ecosystems. With the purpose of determining the presence and abundance of public interest microorganism in recent sediment samples, analyzing samples were taken from the reservoirs major entrance compartments (Tietê and Piracicaba rivers)and the region of confluence between both. Samples were analyzed by Chromocult kit, determining the presence and abundance of coliforms, Escherichia coli e Salmonella sp. The results indicate that there is a high Salmonella concentration in all collection stationsshowing poor sanitary and environmental conditions and considering the inter-relations between sediment and water column there is the possibility of compromising recreational activities and vegetable irrigation.