Soil sodium, magnesium and potassium contents contribute to metals uptake and accumulation in leaves of Atriplex halimus in tailings ponds

• Published in: Journal of environmental chemical engineering Vol. 10; no. 3; p. 107948
• Main Authors: Shahrokh, Vajihe, Perez, Vilcky, Zornoza, Raul, Acosta, Jose A., Faz, Angel, Martinez-Martinez, Silvia
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-06-2022
• Subjects: Atriplex halimus; Bioaccumulation factor; Heavy metals; Macronutrients; Phytoremediation; Atriplex halimus; Macronutrients; Bioaccumulation factor; Heavy metals; Phytoremediation
• ISSN: 2213-3437; 2213-3437
• DOI: 10.1016/j.jece.2022.107948

Accumulation of tailings results in environmental risks due to the transfer of toxic elements through erosion and/or leaching. The most common reclamation strategy has been phytotechnologies application. Atriplex halimus is a species adapted to the soils developed over tailings. This study aimed to assess: i) the efficacy of A. halimus in phytoremediation of contaminated salt-affected soils, ii) how soil properties, especially macronutrients, affect metal uptake by A. halimus and iii) A. halimus ability to change soil characteristics. Four tailings ponds were sampled where A. halimus grew: three were reclaimed by marble waste, pig slurry and pig manure owing to lack of vegetation, and the other was spontaneously colonized. Different soil properties, metal fractions of rhizospheric and non-rhizospheric soils and metals absorption by A. halimus tissues were analyzed. Rhizosphere showed higher total organic carbon (TOC), inorganic carbon (IC), and soluble and total K than the non-rhizospheric soils. A. halimus had an accumulation capacity of metals mostly in leaves, followed by stems, with bioaccumulation factors for metals > 1. Our findings showed that besides the general soil properties, including pH, IC and TOC, electrical conductivity and the soil soluble fractions of Na, Mg and K were the key factors contributing to the metals accumulation in A. halimus leaves. A. halimus has been previously used and encouraged in phytoremediation strategies. However, owing to its high accumulation of metals in shoots, this species should be avoided in soils with high content of salts and heavy metals, since it could contribute to their spread.
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•A. halimus, a halophytic species, applied for phytoremediation of tailings ponds.•A. halimus accumulated higher content of metals in leaves than in root and stem.•Bioaccumulation factor for metals in leaves was high.•Soil EC and soluble Na, Mg and K increased accumulation of metals in leaves.