Assessment of Pb uptake, translocation and immobilization in kenaf (Hibiscuscannabinus L.) for phytoremediation of sand tailings
HO Wai Mun , ANG Lai Hoe , LEE Don Koo
DOI:
Received November 02, 2007,Revised January 15, 2008, Accepted , Available online
Volume 20,2008,Pages 1341-1347
- Summary
- References
- Related Articles
The potential of kenaf (Hibiscus cannabinus L.) for phytoremediation of lead (Pb) on sand tailings was investigated. A pot experiment
employing factorial design with two main e ects of fertilizer and lead was conducted in a nursery using sand tailings from an ex-tin
mine as the growing medium. Results showed that Pb was found in the root, stem, and seed capsule of kenaf but not in the leaf.
Application of organic fertilizer promoted greater biomass yield as well as higher accumulation capacity of Pb. In Pb-spiked treatments,
roots accumulated more than 85% of total plant Pb which implies that kenaf root can be an important sink for bioavailable Pb. Scanning
transmission electron microscope (STEM) X-ray microanalysis confirmed that electron-dense deposits located along cell walls of kenaf
roots were Pb precipitates. The ability of kenaf to tolerate Pb and avoid phytotoxicity could be attributed to the immobilization of Pb
in the roots and hence the restriction of upward movement (translocation factor < 1). With the application of fertilizer, kenaf was
also found to have higher biomass and subsequently higher bioaccumulation capacity, indicating its suitability for phytoremediation of
Pb-contaminated site.
