Soil-plant analyses to determine the bioindication and bioaccumulation capacity of native vascular plants in dismissed mining area of Calabria region (S-Italy)
(1)Department of Biology, Ecology and Earth Sciences (DiBEST), University of Calabria, Arcavacata di Rende, CS, Italy (2)Institute on Membrane Technology (ITM-CNR), Arcavacata di Rende, CS, Italy
Numerous studies identified mining as a primary source of heavy metal pollution. In Calabria region (S-Italy), mining activities date back to the Roman age, up to the early 21st century. The presence of these dismissed mining areas poses potential risks to human and ecosystem health, but it also offers a unique opportunity to investigate the bioindication and bioremediation potential of the related native flora. Indeed, identification of species useful for bioindication and bioremediation is crucial for assessing and mitigating the environmental risk in polluted areas. Nonetheless, no data are currently available on levels of heavy-metal contamination in Calabria dismissed mining areas, nor on the capacity of related vascular flora to bioaccumulate these elements. Therefore, a task including botanists and geologists was recently constituted at University of Calabria. Here, we show the outcomes of an in-depth analysis of heavy metal concentrations in soils and plants at two different locations: (i) an arsenopyrite mining site found in S-Eastern Calabria, and (ii) an uncontaminated control site (Botanical Garden of University of Calabria). Soils and a set of spontaneous plant species were sampled at both sites and subsequently analysed trough a ICP-MS technique. The results showed that concentrations of Co, Cu, As, Cd and Pb in the mine soils exceed the legal limits. Among the sampled plants, Asparagus acutifolius L., Cistus salviifolius L., Dittrichia viscosa L., Erica arborea L., and Reichardia picroides L. collected in the mine site revealed a higher concentration of various heavy metals compared to the control site. Moreover, a translocation factor (TF) >1 was found in A. acutifolius for As and Cd, in C. salviifolius for Ni, Cu, As, in D. viscosa for Ni, Cu, As, Cd, and Pb, and in R. picroides for Ni, Cu, As, Cd, and Pb. This work provided preliminary information on the ability of the surveyed species to accumulate heavy metals, thus offering insights for the phytomanagement of the studied contaminated area.
Keywords: Heavy metals; mining areas; bioaccumulation; bioindication; bioremediation; pollution; vascular plants.
