Phytoremediation of a chromium contaminated site by selected species

An experimental test has been carried out for hexavalent chromium removal from irrigation water, using two selected plant species (Phragmites australis and Ailanthus altissima) planted in soil contaminated with hexavalent chromium. Total chromium removal from water was ranging from 55 % (Phragmites) to 61 % (Ailanthus). After 360 days the contaminated soil dropped from 70 (initial) to 36 and 41 mg Cr/kg(dry soil), for Phragmites and Ailanthus, respectively. Phragmites accumulated the highest amount of chromium in the roots (1,910 mg Cr/kg(dry tissue)), compared with 358 mg Cr/kg(dry tissue) for Ailanthus roots. Most of chromium was found in trivalent form in all plant tissues. Ailanthus had the lowest affinity for CrVI reduction in the root tissues. Phragmites indicated the highest chromium translocation potential, from roots to stems. Both plant species showed good potentialities to be used in phytoremediation installations for chromium removal