title: Influence of environmental and anthropogenic factors at the bottom sediments in a Doce River tributary in Brazil.
abstract: In developing countries, it is uncommon to find watersheds that have been the object of detailed environmental studies. It makes the assessment of the magnitude of environmental impacts and pollution of these sites difficult. This research demonstrated ways to understand the dynamics of river bottom sediments contamination, even for watersheds with a lack of environmental data. Based on geochemical affinity, we conducted a comprehensive study on the concentration of metals and metalloids. Then, we discussed the probable origin of the concentration of these elements at the bottom sediment along the Matipó River. The Matipó River is an important tributary of the Doce River, which stood out in international headlines because of the mining tailing dam disaster in Mariana, Minas Gerais, in 2015. The bottom sediment samples were taken in 25 stations located along the basin in different seasonal periods. The results showed that copper ([Formula: see text] = 464.7 mg kg-1) and zinc ([Formula: see text] = 287.7 mg kg-1) probably have natural origin, despite of the high concentrations. Lead ([Formula: see text] = 28.0 mg kg-1), chromium ([Formula: see text] = 153.2 mg kg-1), and nickel ([Formula: see text] = 41.8 mg kg-1) also had high concentrations at some collecting stations, and this probably reflected the local natural conditions. The bedrock of the studying basin is dominantly composed of metabasalts and metatonalites interlayered with calcitic and dolomitic metalimestone. On the other hand, the concentration was worrisome in stations near human activities, possibly due to impacts caused by unsustainably agriculture and livestock.
authors.affiliation: Universidade Federal de Ouro Preto (UFOP), Morro do Cruzeiro, S/N, Ouro Preto, MG, 35400-000, Brazil. deysereis.reis@gmail.com.
authors.forename: Deyse Almeida
authors.initials: DA
authors.lastname: Dos Reis
authors.affiliation: Universidade Federal de Ouro Preto (UFOP), Morro do Cruzeiro, S/N, Ouro Preto, MG, 35400-000, Brazil.
authors.forename: Aníbal
authors.initials: A
authors.lastname: da Fonseca Santiago
authors.affiliation: Universidade Federal de Ouro Preto (UFOP), Morro do Cruzeiro, S/N, Ouro Preto, MG, 35400-000, Brazil.
authors.forename: Laura Pereira
authors.initials: LP
authors.lastname: Nascimento
authors.affiliation: Universidade Federal de Ouro Preto (UFOP), Morro do Cruzeiro, S/N, Ouro Preto, MG, 35400-000, Brazil.
authors.forename: Hubert Mathias Peter
authors.initials: HM
authors.lastname: Roeser
mesh_terms: D000383:Agriculture; D001938:Brazil; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D058955:Metalloids / Q000032:analysis*; D019216:Metals, Heavy / Q000032:analysis*; D045483:Rivers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D058955:Metalloids; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical
keywords: Bottom sediments pollution; Doce River; Geochemical affinity; Matipó River; Metals