title: Comparison of EDTA-enhanced phytoextraction and phytostabilisation strategies with Lolium perenne on a heavy metal contaminated soil.
abstract: Phytoremediation is a promising and cost-effective strategy to manage heavy metal polluted sites. In this experiment, we compared simultaneously phytoextraction and phytostabilisation techniques on a Cd and Zn contaminated soil, through monitoring of plant accumulation and leaching. Lolium perenne plants were cultivated for 2 months under controlled environmental conditions in a 27.6 dm(3)-pot experiment allowing the collect of leachates. The heavy metal phytoextraction was promoted by adding Na-EDTA (0.5 g kg(-1) of soil) in watering solution. Phytostabilisation was assessed by mixing soil with steel shots (1%) before L. perenne sowing. Presence of plants exacerbated heavy metal leaching, by improving soil hydraulic conductivity. Use of EDTA for phytoextraction led to higher concentration of heavy metal in shoots. However, this higher heavy metal extraction was insufficient to satisfactory reduce the heavy metal content in soil, and led to important heavy metal leaching induced by EDTA. On the other hand, addition of steel shots efficiently decreased both Cd and Zn mobility, according to 0.01 M CaCl(2) extraction, and leaching. However, improvement of growth conditions by steel shots led to higher heavy metal mass in shoot tissues. Therefore, soil heavy metal mobility and plant metal uptake are not systematically positively correlated.
authors.affiliation: Groupe de Recherche en Physiologie Végétale, Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgium. thomas.lambrechts@uclouvain.be
authors.forename: Thomas
authors.initials: T
authors.lastname: Lambrechts
authors.forename: Quentin
authors.initials: Q
authors.lastname: Gustot
authors.forename: Eléonore
authors.initials: E
authors.lastname: Couder
authors.forename: David
authors.initials: D
authors.lastname: Houben
authors.forename: Anne
authors.initials: A
authors.lastname: Iserentant
authors.forename: Stanley
authors.initials: S
authors.lastname: Lutts
mesh_terms: D001673:Biodegradation, Environmental; D002104:Cadmium / Q000302:isolation & purification*; D004492:Edetic Acid / Q000737:chemistry*; D008129:Lolium / Q000378:metabolism*; D012987:Soil / Q000032:analysis; D012989:Soil Pollutants / Q000302:isolation & purification*; D015032:Zinc / Q000302:isolation & purification*
chemical_list: D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium; D004492:Edetic Acid; D015032:Zinc