Phytoremediation of Heavy Metal by Six Plants

• Main Authors: Yi-Hao Wu, 吳翊豪
• Other Authors: Shun-Cheng Wang
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/24397706887774631768

碩士 === 朝陽科技大學 === 環境工程與管理系碩士班 === 97 === Heavy metal phytoremediation techniques are especially useful tool that are limited to surface layer of soil in Taiwan. Chelating agent are frequently used to increase the bioavailability of heavy metal, Thus enhancing their uptake by plants. Although this may also decrease their biomass. These effects need to be further investigated especially in Taiwan environments when phytoremediation technique that been little used. This study was design to explore the use of six native plants species along with EDTA (ethylenediamine tetraacetic acid) chelating agent for phytoremediation of soil of Chunghwa heavy metal contamination area. The effects of a range of parameter such as basic characteristic of treated soil, water content, biomass of treated plants, and heavy metal content in treated plants were studied. The six native plants species including Celosia argentea L. , Sedum formosanum N.E. Br., Kalanchoe laciniata (Linn.) DC. , Fagopyrum esculentum Moench, Lolium perenne ,and Polygonum plebeium R. Br. were chosen for indicator plants with test. A greenhouse pot experiment and a laboratory leaching columm experimemt to study the EDTA enhancement and phytoextration of heavy metal during the phytoremediation process.The treated soil was taken from the Chunghua irrigation wastewater channel. The soil was high concentration in As, Cd, Cu, Hg, Ni, Zn, especially in Cu and Zn content by chemical analysis. The result revealed that all six treated plants could survive in high heavy metal contaminated soil. Celosia argentea L. have lowed water content in all treated plants. Kalanchoe laciniata (Linn.) possessed the highest biomass in all treated plants. The sequence of uptake ability of heavy metal in tested plants from contamination soil were Zn> Ni> Cu> Cr> Cd> Pb . The EDTA chelating addition on Celosia argentea L. and Fagopyrum esculentum Moench in heavy metal contamination soil, enhancement of Ni and Cr, Ni uptake, respectively. The addition of EDTA in Lolium perenne showed no synergistic uptake effect of heavy metal in contamination soil. In conclusion, Lolium perenne possessed the fast plant growth and seeding in phytoremediation process. Lolium perenne seems be a high potential ability for heavy metal uptake from contamination soil in all these tested plants.