Phytoremediation of potential toxic elements by native tree species in mined-spoiled soils in Mátraszentimre, Hungary

Abstract

Potential toxic elements such as Arsenic (As), Cadmium (Cd), Copper (Cu), Lead (Pb), and Zinc (Zn) are commonly left behind after mining operation. Being non-biodegradable, these elements serve as source of contamination for the soil and water ecosystems and create hazards to human health. This research work evaluated the phyto extracting ability for potential toxic elements by four (4) endemic tree species that are predominantly growing in an abandoned mining spoil sites in Mátra mountains in Hungary. Plant and soil samples were collected in the field and analyzed using ICP-OES. Results showed that the soil was highly

contaminated with heavy metals, largely Pb, As, and Zn which were 10x to 60x more than the typical non- contaminated Hungarian soil. Among the trees evaluated, Carpinus betulus showed the highest potential for

Pb dendroremediation, having a mean concentration value of 4071.67 mg kgˉ1dry weight in roots, 439.06 mg kgˉ1dry weight in stems and 92.53 mg kgˉ1 dry weight in leaves. Betula pendula and Salix caprea bioaccumulated 475.8 and 395. 97 mg kgˉ1 dry weight of Zn in their leaf biomass. Both trees had a Bioconcentration Factor (BCF) value of >1.0 but < 10 which classified them as potential phytoextractors of Zn. Salix caprea gave the highest Translocation Factor (TF) for Cd while Betula pendula gave the highest TF for Zn.