Impacto ambiental de lixões e aterros sanitários em recursos hídricos

Abstract

Water contamination is a prominent issue in Brazil and in the world, as it is a resource of vital importance for all living beings. Since the beginning, man has established himself close to water sources for his survival, which has had consequences for the availability and quality of the resource. Population growth has increased the demand for water consumption, as all activities use the resource, generating contaminating waste/effluents. Heavy metals, microorganisms, radioactive elements and urban solid waste (MSW) are examples of how human activities impact water resources. MSW represent a great potential source of contamination for water bodies, mainly due to inadequate disposal in areas. This dissertation sought, at first, to establish an overview of science in Brazil and in the world about the contamination of water resources by areas of MSW disposal. A growth of studies was detected in the last 10 years. The form of destination was not related to the number of research articles. Moderate correlations were obtained between the amount of MSW and the population of the countries with the number of articles searched. High correlations were found between the production of MSW with the population of countries and the number of articles on MSW as a whole. There was a low production of articles both in Brazil and in the world related to the subject of this study, but further research in other databases should be carried out for this confirmation. Subsequently, an experimental field study was carried out on contamination in ten different springs in the state of Goiás, five of them near dumps and five near landfills. In each one, upstream and downstream collections were made. The samples were analyzed for physical- chemical, microbiological and ecotoxicological parameters in Allium cepa. Land use analyzes were also carried out in the hydrographic basins of the points to determine possible patterns of differentiation in water quality. The results indicated: microbiological contamination at all points with total coliforms and Escherichia coli; physical-chemical parameters were in accordance with CONAMA resolution 357/2005, except for color, which did not fit into three points; there were no differences in water parameters near landfills and dumps or upstream and downstream; there were no differences in root length of Allium cepa between landfills, although growth inhibition occurred; between dumps there were differences from one location to the others; Principal component analysis (PCA) between physicochemical variables, root length and land use showed that conductivity, forest formation, savanna and grassland formation were the variables that most influenced the differentiation between the samples.