PROTECTION OF RIPARIAN FORESTS AND WATER QUALITY IN A BASIN IN THE ATLANTIC FOREST BIOME

Resumo

Abstract

The water quality of a drainage basin depends on the vegetation and soil of the region, land use and riparian forests, which act as a filter to protect the watercourse. For three years, we monitored several water quality parameters (turbidity, color, pH, conductivity, dissolved solids, alkalinity, and nitrate and chloride concentrations) in six adjacent microbasins to assess how riparian forests and land use affect water quality. The location is part of the Atlantic forest biome, with high-altitude humid subtropical climate and mixed ombrophilous forests. We designed a land use charter of the basin and a conflict map for fluvial permanent preservation areas. Land use included mainly natural forests, forestry, buildings, agriculture, and pastures. The multiple correlation analyses included: the water quality parameters, conflicts with permanent preservation areas, and land uses in river basins. In 51% of the basin, land uses complied with fluvial PPA legislation, but in 49% we found conflicts with other land use typologies and a lack of riparian forests. The quality of the water changed throughout the seasons and when fluvial PPAs conflicted with agriculture, buildings, and pastures. The different land uses in the basins did not influence the parameters of water quality and the same occurred with precipitation on water quality.