Reference Values of Soil Quality for the Rio Doce Basin

Abstract

The great geological and soil variation in the state of Minas Gerais, Brazil, indicates the need for regional studies to understand the geochemical background of soils. The Rio Doce Basin became a priority area for geochemical background determination after the rupture of the tailings dam of Fundão in 2015. In this context, the objectives of this study were to propose Reference Values of Soil Quality in the Rio Doce Basin, to define variables that can predict metal(loid) concentrations in the soil, and to examine the correlation between metal(loid) concentrations determined by X-ray fluorescence and by the traditional method. One hundred and seven samples were collected from minimally disturbed areas, representing the main soils and source materials. Metal(loid)s were determined by acid digestion and X-ray fluorescence. Descriptive statistics of the data, as well as the calculation of the Randomized Dependence Coefficient (RDC) and Principal Component Analysis (PCA) were carried out. The soils were found to be acidic, dystrophic with low Mehlich-1 extracted P contents, and have a variable texture. The coefficient of determination ranged from 0.4 to 0.9, suggesting X-ray fluorescence as a promising technique for determining metal(loid) concentrations in soils. The absence of correlation between clay and organic matter contents with metal(loid) concentrations suggests that the latter were inherited exclusively from the parent material, with little influence of pedogenesis. Metal mineralization in the highlands that constitute the topographic drainage divide of the basin increase the reference values of soil quality to higher values than established for the State of Minas Gerais.

Lead acetate ecotoxicity in tropical soils

“…Lead concentrations in the soils for the control treatment (without the addition of Pb) were 4.1, 9.9, and 7.6 mg kg − 1 in the Oxisol, Inceptisol, and TAS, respectively. These concentrations for natural soils (Oxisol and Inceptisol) are within the range of values considered normal for Pb background in the area (Guevara et al 2018). The concentrations of Pb in the AcPb treatments in the Oxisol, Inceptisol, and TAS represented the added Pb concentration (Table 2 and Table 3).…”

Determination of local background and baseline values of elements within the soils of the Birimian Terrain of the Wassa Area of Southwest Ghana

“…The recovery rates for the certified reference material (known also as standard sample) varied between 87.5% and 120% (Table 1). This is considered satisfactory for the study relating the calculated recovery rates in a similar study in Rio Doce Basin in Brazil (Guevara et al, 2018).…”

Mudanças climáticas e vulnerabilidade na agricultura familiar da região Rio Doce, Minas Gerais, Brasil

“…Sendo assim, tais municípios possuem altos índices de exposição e sensibilidade. Mesmo considerando que os solos da bacia 244 DOS SANTOS, DE ANDRADE, DA CUNHA do Rio Doce sejam homogêneos e que os rejeitos não alteraram significativamente os teores de metais (Guevara et al, 2018), a vulnerabilidade ambiental é marcada pela perda da vegetação nas matas ripárias, bem como zonas de amortecimento ao longo da Bacia. Por outro lado, o conteúdo de nutrientes e minerais (P, K, Ca, Mg, Cu, Fe, Mn, Zn e NO) e a matéria orgânica do solo dos sedimentos foram esgotados nas zonas ripárias ao longo da bacia após o desastre (Santos et al, 2019).…”