Forest Species with Bioaccumulatory Potential of Heavy Metals in Mining Areas in the Ecuadorian Amazon

Abstract

The study aimed to evaluate the potential bioaccumulation of heavy metals in tree and shrub species in the Simón Bolívar zone, El Capricho parish, Carlos Julio Arosemena Tola canton, Napo Province, Ecuador, an area previously affected by illegal gold mining activities. The bioconcentration factor of six species was analyzed based on the ratio of heavy metal concentrations in leaves to soil. Leaf-level results revealed that Iron (Fe) accumulated most in Acalypha diversifolia Jacq. and Cedrela odorata L., while Theobroma cacao L. showed higher Zinc (Zn) accumulation, indicating their potential for phytoremediation in contaminated areas. Regarding soil metal concentrations, C. odorata exhibited the highest levels of Fe, Zn, Copper (Cu), and Lead (Pb), whereas A. diversifolia had the lowest. Based on the bioconcentration factor (BCF), A. diversifolia demonstrated the highest potential for absorbing Fe, Cu, and Pb, significantly differing with elevated values compared to other species. These findings could inform soil remediation strategies using these potential species to mitigate toxic elements in the study area.