Department Of Environmental Science And Technology

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Author: search.filters.author.da Costa, Marlene Furtado

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    Methodological approach and general guidelines to geochemical mapping and background-baseline analysis for environmental assessment: a case study in the Caraj�s Mineral Province, Brazil
    (Sociedade Brasileira de Geologia, 2023-01-09T00:00:00) Souza-Filho, Pedro Walfir Martins; Sahoo, Prafulla Kumar; da Silva, Marcio Sousa; Dall�Agnol, Roberto; Filho, Carlos Augusto Medeiros; Leite, Alessandro Sab�; da Silva Ferreira J�nior, Jair; da Rocha Nascimento, Wilson; da Silva e Silva, G�ssica; Salom�o, Gabriel Negreiros; Sarracini, Fabiana; Junior, Renato Oliveira Silva; da Costa, Marlene Furtado
    We present this manuscript as a methodological approach and general guidelines for geochemical mapping and background/baseline projects for environmental assessment in tropical areas. A case study was carried out in the Itacai�nas River watershed (IRW), Eastern Amazon, to fill in a gap in knowledge on the distribution of chemical elements, particularly those potentially toxic, in the near-surface environment of the area. The high-impact results of this research project revealed the need for similar scientific investigation across the globe with the implementation of a systematic methodology. The study shows, for example, the importance of well-planned field activities, multi-medium sampling, analytical methods, laboratory procedures, database construction, and general aspects of data processing and statistical treatment. The importance of this contribution is that it can be used as a reference in support of geospatial analysis in research within the scope of geochemical mapping and background-baseline projects. The database is accessible through a web-based geographic information system front-end; a Geochemical Atlas of the IRW will be available as soon as possible. � 2022 The authors.
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    Soil-sediment linkage and trace element contamination in forested/deforested areas of the Itacai�nas River Watershed, Brazil: To what extent land-use change plays a role?
    (Elsevier B.V., 2022-03-08T00:00:00) Dall'Agnol, Roberto; Sahoo, Prafulla Kumar; Salom�o, Gabriel Negreiros; de Ara�jo, Alessandra Danieli Miranda; da Silva, Marcio Sousa; Powell, Mike A.; Junior, Jair Ferreira; Ramos, Silvio Junio; Martins, Gabriel Caixeta; da Costa, Marlene Furtado; Guilherme, Luiz Roberto Guimar�es
    Trace elements (TE) contamination in forested areas of the Itacai�nas River Watershed (IRW), Brazilian Amazon, arouses growing interest owing to the rapid deforestation and mining activities. In this study, soils (surface, SS; bottom, BS) and stream sediments (SD) from forested/deforested areas of IRW were analyzed with the aim of (1) evaluating the major sources of TE (mainly As, Ba, Cd, Cu, Co, Cr, Hg, Mo, Mn, Ni, Pb, V, and Zn), and (2) examining the soil-sediment TE link related to land-use change and/or geologic factors. Compositional data analysis (CoDA) was used to eliminate data closure issues and the centred log-ratio (clr) transformation yielded better results in Principal Component Analysis (PCA). The TE distribution pattern was significantly different (p < 0.05) between forested and deforested areas, but in both areas the TE distribution pattern is significantly correlated between SS, BS, and SD, indicating a strong lithogenic control. PCA (clr-transformed) identified the major geochemical bedrock signature as Fe-Ti-V-Cu-Cr-Ni, which is nearly similar in soil and sediments. The more accentuated enrichment and the maximum number of anomalies of these elements were found in the Caraj�s Basin and are highly coincident with mineral deposits/local lithologies without clear indication of anthropogenic contamination from point sources. Besides geogenic factors, deforestation is also affecting TE distribution in the basin. In deforested areas, Mn was significantly enriched in the surface horizon. Furthermore, linear regression analysis shows stronger TE relationships between soils and sediments in deforested areas than in forested ones, reflecting higher erosion in the former. This could be the reason for the relatively higher enrichment of TE (e.g., Fe, Mn, Cu, Cr, Ni) in deforested sediments. The TE contamination using regional background values provides more accurate results than worldwide reference values. Thus, the former should be considered for a more realistic environmental risk assessment in IRW and other forest ecosystems in the Brazilian Amazon. � 2022 Elsevier B.V.