Avaliação de parâmetros indicadores da qualidade da água para verificar o estado de conservação das represas I, II e III do rio Ipitanga e estabelecer um modelo estatístico de previsão da degradação deste recurso hídrico

Abstract

The natural resources and protection of human health have a central role in the discussions of the contemporary world. In Brazil, for the past decades, the industrialization, the irregular occupation and the concentration of population in urban centers increased in an accelerated proportion. Due to this reality, many conflicts and problems have been created, such: increased risk of degradation in the areas of water supply and food; floods; reduction of the biodiversity and habitats, insertion of poisonous substances in the food chain; pollution of the water by domestic and industrial sewers and by the disposal of the residues in an inadequate way, among others. The area in study is inserted basically in an urban district of intense industrial production, and its impacts are an environmental problem caused by the real estate exploration, deforestation, inadequate disposal of the residues and release of domestic and industrial effluents without any treatment. So, the planning of the use and urban occupation around dams I, II and III of river Ipitanga is of extreme importance, considering, that its waters contributes with 40% of the provisioning of the metropolitan area of Salvador (RMS). Considering these facts, the objective of this work is to evaluate, according to statistical criteria, if certain characteristics of the water of Ipitanga I (IP I), Ipitanga II (IP II) and Ipitanga III (IP III) dams, are being altered through the years, using as reference the Resolution 357/05 of CONAMA considering the influence of the emission of pollutants in the water of those dams because of the urban occupation, by the quantification of the variables DBO, OD, pH, ion ammonium, total phosphorus, turbidity, thermotolerant coliforms and room temperature obtained from the secondary data of EMBASA. The Pearson correlation coefficient and the linear regression were used to treat the data of the monitoring net of quality of water from EMBASA. The presupposition considers the statistical evaluation of these variable studied in the water of river Ipitanga as a possible instrument to identify points of improvement and implementing a plan of use and urban occupation as well as and environmental preservation. Although the behavior of the studied variables doesn´t override the values predicted by the Resolution 357/05 of CONAMA, the anthropic effects observed in the field indicate the occurrence of a growing process of degradation of the river Ipitanga year by year.