| 英文摘要 |
This site including the Land Registered Number. 1438 and 1439 at Wangdang Township, Pingtung was contaminated by multiple heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn), which has not been practically remediated after the survey of contaminated area and degree confirmation in 2008. According the conclusion from this survey, it will cost 40 million NT dollars to remediate this site by traditional chemical and engineering approaches which disadventages are lowering soil quality and generating much waste. Therefore, this study is to perform the evaluation of remediation by phytoremediation approach. From the results, the phytostabilization species including Scandent Scheffera, Pachira macrocarpa, Broussonetia papyrifera, and Vetiveria zizanioides show a good ability in fixing the metals in their roots to minic the metals leaching and diffusion at the site. The maximum concentrations of Cr, Cu, Ni, Pb, and Zn in the roots are respectively 149, 354, 145, 168, and 434 mg/kg. However, the site was flooded seriously in the rainy season of 2012, and thus only Vetiveria zizanioides survived. After there, the metals concentrations in the root of Vetiveria zizanioides were slightly lower than those of the other phytostabilization species, but the root system of Vetiveria zizanioides was wide and strong to effectively stabilize the contaminated soil in reducing the potential of soil erosion, runoff, and leaching in the environment. The phytoextraction species including Ricinus communis L., Swietenia macrophylla, Salix viminalis L., Zea mays L., and Helianthus annuus Linn. show various efficiency of phytoextraction in Cr, Cu, Ni, Pb, and Zn during 2-month growth with the maximum concentrations of 124, 216, 70, 118, and 209 mg/kg respectively. Considering the translocation factor (TF), Ricinus communis L. and Salix viminalis L were the highest. Zea mays L., and Helianthus annuus Linn. were lower in TF values, but their growth rate and biomass were higher than the other species.
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