EDTA-Assisted Phytoremediation of Heavy Metals in Composted Biosolids. (3498)
Authors:
M.S. Liphadzi - Kansas State Univ.
M. Kirkham* - Kansas State Univ.
Abstract:
Biosolids can be applied to land either as a liquid or as composted material. No studies compare the availability of heavy metals in composted biosolids with soil containing applied (non-composted) biosolids after solubilization with chelates to facilitate phytoremediation. The objective of this work was to determine the effect of the chelate EDTA on uptake by hybrid poplar of heavy metals in either 1)
composted biosolids or 2) soil with incorporated biosolids. Poplar seedlings were planted in the two media, which were in columns in a greenhouse. The chelate was added after 133 days of growth, and the saplings then grew for another 162 days. In general, EDTA did not affect concentrations of heavy metals (Cd, Cu, Fe, Mn, Ni, Pb, Zn) in the plants. Concentrations of the heavy metals were higher in the
composted biosolids than in the soil with biosolids, and EDTA had no effect on these concentrations. Poplar grew better in the soil with biosolids than in the
composted sludge, probably because of the extremely high saline conditions in the compost (electrical conductivity of 13.5 dS/m) compared to the soil with biosolids (EC of 4.4 dS/m). The results showed that the chelate had little or no impact on phytoremediation of heavy metals in the two media and that soil with biosolids was a better growth medium than composted biosolids.
Speaker Information: M.B. Kirkham, Kansas State Univ., Dept. Agronomy 2004 Throckmorton Hall Kansas State Univ., Manhattan, KS 66506-5501; Phone:
785-532-0422; E-mail: [email protected]
Session Information: Tuesday, November 2, 2004, 10:00 AM-12:00 PM Presentation Start: 10:00 AM (Poster Board Number: 1584)
Keywords: phytoremediation; poplar; heavy metal; biosolids
