Seasonal variations of Cu, Zn, Ni and Cr concentration in Phragmites australis (Cav.) Trin ex steudel in a constructed wetland of North Italy

The current study evaluates the potential amelioration of the water quality of the Po River by monitoring the accumulation of four heavy metals, Cu, Zn, Ni and Cr, in Phragmites australis plants growing within an experimental constructed wetland (CW) sited in Castelnovo Bariano. The plant growth rate displayed during the time of study was typical of this plant species. The level of heavy metals was generally higher in rhizomes and stems than in leaves during the growing season, and increased notably in the leaves in December. Given these results, it may be inferred that P. australis plants may be efficiently utilized for metal removal depending upon the harvesting time of the aboveground tissues.