Caracterização dos sistemas praiais adjacentes à foz do Rio Doce (Espírito Santo, Brasil) quanto aos teores de elementos químicos em sedimentos e material particulado em suspensão

• Ano de defesa: 2022
• Autor(a) principal: Krause, Maiara
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Doutorado em Química; Centro de Ciências Exatas; UFES; Programa de Pós-Graduação em Química
• Palavras-chave em Português: Praia; Rio Doce; Sedimento; Composição elementar; Rompimento barragem; Rejeito de mineração; subject.br-rjbn; Química
• Link de acesso: http://repositorio.ufes.br/handle/10/16585

The beaches on the north coast of Espírito Santo constantly receive pollutants from the Doce River, as a result of the intense occupation and the historic centenary of mining activities in the Doce River Basin. The objective of this study was to evaluate the elemental composition of the beaches adjacent to the mouth of the Doce River, as well as the processes that act in the distribution of these elements. In addition to evaluate the influence of the fluvial input of the Doce River and the possible impacts of the rupture of the Fundão dam in the study area. For this, the chemical elements Al, As, Ba, Co, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn were determined in samples of suspended particulate matter (SPM) and surface sediments from the backshore and shoreface at stations adjacent to the mouth of the Doce River. The decomposition of the samples was performed by the U.S. EPA 3051A. Chemical elements were quantified by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP OES). The results showed that the beaches in the Foz and North sectors of the mouth of the Doce River presented fine sediments on the shoreface and high concentrations of the chemical elements evaluated. This result indicates that river sediments reach the mouth and follow a longitudinal distribution pattern, preferably from south to north. The different sediment quality index (Igeo and SGQ-q) also showed that these sectors have moderate potential to cause adverse effects to biota. In addition, the values of magnetic susceptibility and IMS (%) suggest that mining tailings, arising from the rupture of the Fundão dam, are present in the study area even after almost six years of its arrival on the coast of Espírito Santo.