In situ stabilization of soil lead using phosphorus and manganese oxide: Influence of plant growth

• Published in: Journal of environmental quality Vol. 31; no. 2; pp. 564 - 572
• Main Authors: HETTIARACHCHI, Ganga M, PIERZYNSKI, Gary M
• Format: Journal Article
• Language: English
• Published: Madison, WI Crop Science Society of America 01.03.2002; American Society of Agronomy
• Subjects: Applied sciences; Beta vulgaris - growth & development; Bioavailability; Biodegradation, Environmental; Biological and medical sciences; Biological Availability; Cadmium; Decontamination. Miscellaneous; Earth sciences; Earth, ocean, space; Engineering and environment geology. Geothermics; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Lead; Lead - chemistry; Lead - pharmacokinetics; Manganese; Manganese Compounds - chemistry; Manganese oxides; Non agrochemicals pollutants; Oxides - chemistry; Phosphorus - chemistry; Phytopathology. Animal pests. Plant and forest protection; Plant growth; Poaceae - growth & development; Pollution; Pollution effects and side effects of agrochemicals on crop plants and forest trees. Other anthropogenic factors; Pollution effects. Side effects of agrochemicals; Pollution, environment geology; Soil and sediments pollution; Soil contamination; Soil Pollutants - pharmacokinetics; Soil stabilization; Zinc; Monocotyledones; In situ; Immobilization; Phosphorus; Bioavailability; Superphosphate; Beta vulgaris; Soil pollution; Chenopodiaceae; Heavy metal; Amendment; Manganese oxides; Sorghum bicolor; Absorption; Gramineae; Dicotyledones; Environment impact; Phosphate rock; Angiospermae; Lead; Spermatophyta; Soil plant relation
• ISSN: 0047-2425; 1537-2537
• DOI: 10.2134/jeq2002.5640

In situ stabilization of Pb contaminated soils can be accomplished by adding P and Mn(IV) oxide. However, the long-term efficacy of in situ stabilization under continual P removal through plant growth is unknown. Moreover, the effects these treatments have on phytoavailability of other metals (Cd and Zn) commonly associated with Pb in soil are not well understood. Greenhouse experiments using sudax [Sorghum vulgare (L.) Moench] and Swiss chard [Beta vulgaris (L.) Koch] were carried out to evaluate the effects of plant growth on soil Pb bioavailability to humans after addition of P and other amendments, and the effects of these treatments on Pb, Cd, and Zn phytoavailability in three metal-contaminated soils. Eight treatments were used: zero P; 2500 mg of P as triple superphosphate (TSP); 5000 mg of P as TSP or phosphate rock (PR); 5000 mg of Mn oxide/kg; and combinations of Mn oxide and P as TSP or PR. The addition of P and/or Mn oxide significantly reduced bioavailable Pb, as measured by the physiologically based extraction test (PBET), in soils compared with the control even after extensive cropping. The PBET data also suggested that removal of P from soluble P sources by plants could negate the beneficial effects of P on bioavailable Pb, unless sufficient soluble P was added or soluble P was combined with Mn oxide. In general, Ph, Cd, and Zn concentrations in shoot tissues of sudax and Swiss chard were reduced significantly by TSP and did not change with the addition of PR. The combination of PR and Mn oxide significantly reduced Pb concentrations in plants compared with the control.