Phytoremediation potential of Leersia hexandra Swartz of copper contaminated soil and its enhancement by using agronomic management practices

摘要

The objective of this study was to discuss the phytoremediation potential of Leersia hexandra Swartz in Cu contaminated soil and its enhancement by agronomic management practices. The results showed that L. hexandra had a high extraction capacity for copper (Cu), and Cu concentration was found maximum in shoots (755.4 mg/kg), which is very close to the Cu-hyperaccumulators. Three successive harvests did not reduce the biomass and Cu level in shoots of L. hexandra (p 0.05), indicating that sequential harvest was feasible for the increase of total biomass and Cu extraction amount. Fertilization could obviously increase the tissue dry weight, resulting in the total amount of extracted-Cu up to 52.3%. 3-Indole acetic acid (IAA) also significantly increased biomass, causing the efficiency of Cu phytoextraction up to 204.6%. These suggested that fertilization and IAA were effective for enhancing Cu phytoextraction by L. hexandra.