Urban trees as bioindicators and mitigators of PTEs: the case of Acer platanoides L.

Trees in urban ecosystems not only improve the microclimatic conditions and aesthetic value of urban spaces, but also contribute to the accumulation and redistribution of potentially toxic elements (PTEs), thereby mitigating ecological risks and supporting urban sustainability. In this study, the phytoremediation potential of Acer platanoides L. was assessed by analysing B, Cu, Sr and Zn in soil, roots and leaves from three urban parks in Belgrade. The element concentrations were determined by ICP-OES after microwave digestion (CEM Mars 6). The measured concentrations of B and Sr in leaves reached toxic levels, indicating a potential risk of phytotoxicity of A. platanoides. Bioconcentration and translocation factors confirmed an efficient uptake and transfer of B, but a limited uptake of Cu, Sr and Zn from the soil. The results show that the species is very good at accumulating and translocating B, while it has limited uptake and redistribution of other elements into plant tissue. Due to its relatively rapid growth, stress tolerance and ability to accumulate certain PTEs (especially B), A. platanoides can be considered as an efficient and cost-effective species to improve the resilience and ecological functions of urban green spaces.