Identification of native-metal tolerant plant species in situ: Environmental implications and functional traits

A study was undertaken to identify suitable native plants for the phytoremediation of the second largest integrated steelworks in Italy (Bagnoli brownfield site). A phytoecological survey allowed us to identify 139 plant taxa belonging to 58 different families. The most represented families were in the decreasing order Poaceae > Fabaceae > Asteraceae > Apiaceae. The biological spectrum showed a predominance of Therophytes > Hemycriptophytes > Phanerophyte. Seventy-six sites were selected on the presence of colonist's plants and vegetation assemblage patterns. At each site, roots and leaves of the dominant plant and rhizosphere soils were sampled. Total content of metal(loid)s in soils and plant parts were determined. Agronomic soil parameters were studied. Anthropogenic sourced metal(loid)s were discriminated from geochemical ones, and plant metal(loid) accumulation and translocation efficiency were evaluated. The role of many native plant species in terms of TEs phytomanagement strategy was recognizable inside the investigated area. According to this survey of structural plant diversity, several combinations between plants and microorganisms are being further investigated to identify relevant biological system for the phytomanagement of this contaminated area.