Comparative study of trace metal accumulation in native and invasive plant species

Global ecosystems are rapidly changing under human pressures such as land-use change, degradation, and trace metal pollution. These conditions often favor invasive plants, yet the links between invasiveness and metal contamination remain insufficiently understood. This study aimed to compare the biogeochemical responses of a native species (Tanacetum vulgare) and an invasive species (Solidago gigantea). Specifically, their capacity for metal uptake and translocation was investigated to assess whether certain traits may facilitate the performance of invasive plants in contaminated sites. Concentrations of Cd, Cr, Cu, Pb, Zn, Ni, Fe, and Mn were determined in soils and in the roots and aboveground organs of both species sampled in areas with and without industrial impact. The results showed that both species are capable of inhabiting anthropogenically altered and metal-contaminated sites. Importantly, they both exhibited reduced uptake of metals in polluted soils, indicating the utilization of a metal-excluder strategy. T. vulgare was more likely to restrict metal uptake at the root level, whereas S. gigantea appeared to limit metal translocation to aboveground parts. Moreover, S. gigantea contained significantly lower levels of Cd, Ni, and Pb in its organs than T. vulgare, suggesting greater efficiency in avoiding metal accumulation. These findings support the classification of both species as excluders and highlight the adaptive capacity of invasive species in disturbed environments.