Heavy-metal-contaminated industrial soil: Uptake assessment in native plant species from Brazilian Cerrado

ABSTRACT

Plants of the Cerrado have shown some potential for restoration and/or phytoremediation projects due to their ability to grow in and tolerate acidic soils rich in metals. The aim of this study is to evaluate the tolerance and accumulation of metals (Cd, Cu, Pb, and Zn) in five native tree species of the Brazilian Cerrado (Copaifera langsdorffii, Eugenia dysenterica, Inga laurina, Cedrela fissilis, Handroanthus impetiginosus) subjected to three experiments with contaminated soils obtained from a zinc processing industry (S₁, S₂, S₃) and control soil (S₀). The experimental design was completely randomized (factorial 5 × 4 × 3) and conducted in a greenhouse environment during a 90-day experimentation time. The plant species behavior was assessed by visual symptoms of toxicity, tolerance index (TI), translocation factor (TF), and bioaccumulation factor (BF). C. fissilis has performed as a Zn accumulator by the higher BFs obtained in the experiments, equal to 3.72, 0.88, and 0.41 for S₁, S₂, and S₃ respectively. This species had some ability of uptake control as a defense mechanism in high stress conditions with the best behavior for phytoremediation and high tolerance to contamination. With economical and technical benefits, this study may support a preliminary analysis necessary for using native tree species in environmental projects.

KEYWORDS:

• metals accumulation
• phytoremediation
• species from Cerrado
• zinc contamination

Acknowledgements

The authors are grateful to Geraldo Pereira de Sousa (ISTMA); Rita Maria Ferreira da Fonseca and António Alexandre Ventura Araújo (Évora University/PT); and also to the SENAI Institute of Technology in Chemistry for their valuable contributions