Determinação de metais potencialmente tóxicos em amostras de água e sedimentos nas bacias dos rios Cuiabá e São Lourenço - MT

Contamination of water resources is directly linked to anthropic activities. Some of these activities can release metals in the environment which, once in the water, cause great concern since they are not biodegradable, can accumulate in the biota and so reach critical levels causing adverse effects...

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Detalles Bibliográficos
Autor: Gonçalves, Paulo Eduardo Reinach da Silva
Tipo de recurso: tesis de maestría
Estado:Versión publicada
Fecha de publicación:2014
País:Brasil
Institución:Universidade Federal de Mato Grosso (UFMT)
Repositorio:Repositório Institucional da UFMT
Idioma:portugués
OAI Identifier:oai:localhost:1/656
Acceso en línea:http://ri.ufmt.br/handle/1/656
Access Level:acceso abierto
Palabra clave:Metais potencialmente tóxicos
Águas superficiais
Sedimento
Pantanal
CNPQ::ENGENHARIAS::ENGENHARIA SANITARIA::RECURSOS HIDRICOS
Potentialy toxic metals
Surface water
sediment
Descripción
Sumario:Contamination of water resources is directly linked to anthropic activities. Some of these activities can release metals in the environment which, once in the water, cause great concern since they are not biodegradable, can accumulate in the biota and so reach critical levels causing adverse effects to human health and to the environment. The watersheds of Cuiabá and São Lourenço rivers are of great importance since their water is applied to multiple uses, involving the main municipalities of Mato Grosso State. Moreover they are the main affluent of Paraguay river which is the most important contributor to the Pantanal of Mato Grosso. Thus, this study aimed to determine the concentration of Cu, Cr, Cd, Mn, Fe, Pb and Zn in surface water and riverbed sediment of Cuiabá and São Lourenço watersheds. Metals were analysed in water using flame atomic absorption spectrometry and inductive couple plasma emission spectrometry and in sediment using flame atomic absorption spectrometry. The metal concentrations in water were compared to the maximum allowed values established in the Resolution CONAMA n. 357/2005 for class II river waters while for sediments the values established by the Canadian Council of Ministers of the Environment (CCME) were used for comparison. The hierarchical cluster analysis revealed the existence of four groups regarding water quality and two groups of sediment. Discriminant analysis (DA) was applied to evaluate the grouping quality showing a correct classification of 80% of water and 79% of sediment samples. A análise de agrupamento hierárquica (AHA) revelou a existência de quatro agrupamentos para as amostras de água e dois agrupamentos para as amostras de sedimento. Moreover, DA in stepwise forward mode showed that it was possible to reduce the number of evaluated variables keeping the same efficiency in the groups classification. Exceedence curves showed that the majority of metal concentrations were below the limits established in the legislation. However, especial attention should be given to Pb and Cr that were detected in concentrations above these limits in water as well as in sediment samples in some sampling points, probably related to anthropic activities such as domestic and industrial effluents discharge.