TIDE INFLUENCE ON HYDROCHEMICAL PARAMETERS IN TWO COASTAL REGIONS OF SÃO PAULO (BRAZIL) UNDER DIFFERENT ENVIRONMENTAL OCCUPATIONS

Abstract

This study observes the changes in thehydrochemical parameters in function of the tide influencein two coastal environments at São Paulo-Brazil: i)Southern sector (Cananéia region), with hydrologicalproperties strongly associated to tide currents, pluvial inputsand where the salinity reaches high values; ii) Northernsector (Iguape region), submitted to erosion process,agricultural and urban occupation showing lightly sea tideinfluence due to an enormous fluvial input across the ValoGrande Channel. Both regional sectors belong to samecoastal system constituted by estuaries and lagoons formingan estuarine-lagoon complex. The observations wereperformed in a wet period under spring tide influenceincreasing the environmental answers in terms of salinityand dissolved nutrient variations.Index Terms ⎯ Hidrochemistry, nutrients, estuaries.