Effects of Soil Amendment on Growth and Heavy Metals Content in Vetiver Grown on Iron Ore Tailings

Abstract

A greenhouse experiment was conducted to evaluate the effects of soil amendment on growth, performance and the accumulation of primary nutrients as well as Fe, Zn, Mn and Cu in vetiver. Ratchaburi vetiver ecotype plantlets were planted on iron ore tailings amended with compost and chelating agents (EDTA and DTPA). The results indicated that iron ore tailings contained high concentrations of heavy metals with total Fe, Zn, Mn and Cu concentrations of 63,920, 190, 3,220 and 190 mg kg-1, respectively and low contents of primary nutrients and organic matter. The combination of soil amendment materials, especially DTPA and compost, was more effective than sole chelating agents and sole compost in enhancing vetiver growth, nutrient and heavy metals uptake. The soil amendments used in this study did not affect Fe and Zn translocation from vetiver roots to shoots. However, chelating agent amendment could increase Cu translocation, especially in combination with compost, while it slightly decreased Mn translocation. The average mean translocation factors of Mn, Fe, Zn and Cu were 0.86, 0.71, 0.69 and 0.55, respectively. These results indicated that vetiver is a potential plant for phytostabilization and rehabilitation of iron ore mine areas.