Heavy Metals Accumulation in Plants During Coal Mine Reclamation

Abstract

Reclamation solves environmental problems caused by opencast coal mining. Soil contamination with heavy metals is a major problem in restoring the ecosystem of disturbed lands. Plants with good phytoremediation potential may be an optimal solution at the stage of biological reclamation. The research featured the heavy metals accumulation potential in legumes and cereals planted on coal mine dumps. The research objects included soil and plant samples from a coal mine dump near the town of Prokopyevsk, Kemerovo Region. The testing ground (2023) consisted of sections with different options for root formation. The physicochemical properties of soil samples and plant materials were determined by standard methods in accredited laboratories. The sections were planted with herbs, shrubs, and trees; the research reported in this article focused on legumes and cereals. The content of heavy metals in the plant samples stayed below the maximum permissible levels for animal feed. The lead content in plant mass solids fluctuated within 0.35–2.64 mg/kg for cereals and 1.54–5.25 mg/kg for legumes. The cadmium content was 0.13–0.25 mg/kg for cereals and 0.19–0.32 mg/kg for legumes. However, the content of iron in some samples was far above the permissible level and reached 400 mg/kg. In this study, legumes and cereals were able to accumulate potentially hazardous substances, thus reducing their concentration in post-mining soil.