Phytoremediation of Metal-Contaminated Soil in Temperate Humid Regions of British Columbia, Canada

Abstract

The suitability of five plant species was studied for phytoextraction and phytostabilisation in a region with temperate maritime climate of coastal British Columbia, Canada. Pot experiments were conducted using Lolium perenne L (perennial rye grass), Festuca rubra L (creeping red fescue), Helianthus annuus L (sunflower), Poa pratensis L (Kentucky bluegrass) and Brassica napus L (rape) in soils treated with three different metal (Cu, Pb, Mn, and Zn) concentrations. The bio-metric characters of plants in soils with multiple-metal contaminations, their metal accumulation characteristics, translocation properties and metal removal were assessed at different stages of plant growth, 90 and 120 DAS (days after sowing). Lolium was found to be suitable for the phytostabilisation of Cu and Pb, Festuca for Mn and Poa for Zn. Metal removal was higher at 120 than at 90 days after sowing, and metals concentrated more in the underground tissues with less translocation to the aboveground parts. Bioconcentration factors indicate that Festuca had the highest accumulation for Cu, Helianthus for Pb and Zn and Poa for Mn.

KEY WORDS:

• Bioconcentration factor
• metal-contamination
• metal-partitioning
• phytostabilisation
• translocation factor

ACKNOWLEDGMENT

The authors are grateful to Drs. Les Lavkulich for critically reviewing the manuscript. We also thank the B.C. Ministry of Transportation and Infrastructure for financial support.

Notes

*Correlation coefficient was statistically significant at P ≤ 0.05. The strength of relationship was interpreted according to the correlation classification of Hopkins (2000)), namely, negligible: 0.0–0.09; low: 0.1–0.29; moderate: 0.3–0.49; high: 0.5–0.69; very high: 0.7–0.89; nearly perfect: 0.9–1.0.