חיפוש מתקדם
Science of the Total Environment
Fine, P., Inst. of Soil, Water and Environmental Sciences, Volcani Center, ARO, PO Box 6, Bet-Dagan, Israel
Paresh, R., Inst. of Soil, Water and Environmental Sciences, Volcani Center, ARO, PO Box 6, Bet-Dagan, Israel, Department of Earth System Analysis, Faculty of Geo-information Science and Earth Observation, University of Twente, Hengelosestraat 99, Enschede, Netherlands
Beriozkin, A., Inst. of Soil, Water and Environmental Sciences, Volcani Center, ARO, PO Box 6, Bet-Dagan, Israel
Hass, A., West Virginia State University, Dept. of Physics, PO Box 168 InstituteWV, United States
We tested the hypothesis that controlled deficit irrigation (CDI) of the fast growing, salinity resistant Eucalyptus camaldulensis tree with timely EDTA application can enhance sediment clean-up while minimizing leaching of metal complexes. 220-L lysimeters containing a sand-metal-polluted sludge mixture. Established saplings were irrigated with tap or desalinized (RO) water with/without 4-times daily addition of EDTA, EDDS and citric acid. In the 2nd season (2008/9) the chelates were added at 2mM for ≈70summerdays. Diagnostic leaves and soil solution compositions were regularly monitored, the latter by applying prescribed leaching at an overall leaching percentage of ≈0.4%. While the three chelants solubilized sludge metals in batch extraction, EDDS often being the more efficient chelant, EDTA only was effective in the soil system. Leachate and leaves peak average concentrations in EDTA treatment vs. the control treatments were: Cd: 200mgL-1 vs. 1.0 and 67 vs. 21mgkg-1; Cu: 90 vs. 1.5mgL-1 and 17 vs. 3.0mgkg-1; Ni: 60mgL-1 vs. 14 and 20 vs. 6.0mgkg-1; Pb: >44 vs. 0.1mgL-1 and 9.0 vs. 1.0mgkg-1; and Zn: 650 vs. 4.0mgL-1 and 200 vs. 70mgkg-1, all respectively. Peak average leachate EDTA concentration was >60mM, yet acclimating soil microflora gradually degraded most all the EDTA. In incubation study, EDDS and EDTA half-lives in acclimated lysimeter media were 5-11days and ≥27days, respectively. It suggests that sustainable phytoextraction of heavy metals is feasible under careful CDI with EDTA (yet not with biodegradable chelants) augmentation at low doses. Despite that the eucalypt was highly salinity (and EDTA) resistant, CDI using RO water further reduces soil solution salinity, thus increasing the usefulness of this remediation technique. © 2014 Elsevier B.V.
פותח על ידי קלירמאש פתרונות בע"מ -
הספר "אוצר וולקני"
אודות
תנאי שימוש
Chelant-enhanced heavy metal uptake by Eucalyptus trees under controlled deficit irrigation
493
Fine, P., Inst. of Soil, Water and Environmental Sciences, Volcani Center, ARO, PO Box 6, Bet-Dagan, Israel
Paresh, R., Inst. of Soil, Water and Environmental Sciences, Volcani Center, ARO, PO Box 6, Bet-Dagan, Israel, Department of Earth System Analysis, Faculty of Geo-information Science and Earth Observation, University of Twente, Hengelosestraat 99, Enschede, Netherlands
Beriozkin, A., Inst. of Soil, Water and Environmental Sciences, Volcani Center, ARO, PO Box 6, Bet-Dagan, Israel
Hass, A., West Virginia State University, Dept. of Physics, PO Box 168 InstituteWV, United States
Chelant-enhanced heavy metal uptake by Eucalyptus trees under controlled deficit irrigation
We tested the hypothesis that controlled deficit irrigation (CDI) of the fast growing, salinity resistant Eucalyptus camaldulensis tree with timely EDTA application can enhance sediment clean-up while minimizing leaching of metal complexes. 220-L lysimeters containing a sand-metal-polluted sludge mixture. Established saplings were irrigated with tap or desalinized (RO) water with/without 4-times daily addition of EDTA, EDDS and citric acid. In the 2nd season (2008/9) the chelates were added at 2mM for ≈70summerdays. Diagnostic leaves and soil solution compositions were regularly monitored, the latter by applying prescribed leaching at an overall leaching percentage of ≈0.4%. While the three chelants solubilized sludge metals in batch extraction, EDDS often being the more efficient chelant, EDTA only was effective in the soil system. Leachate and leaves peak average concentrations in EDTA treatment vs. the control treatments were: Cd: 200mgL-1 vs. 1.0 and 67 vs. 21mgkg-1; Cu: 90 vs. 1.5mgL-1 and 17 vs. 3.0mgkg-1; Ni: 60mgL-1 vs. 14 and 20 vs. 6.0mgkg-1; Pb: >44 vs. 0.1mgL-1 and 9.0 vs. 1.0mgkg-1; and Zn: 650 vs. 4.0mgL-1 and 200 vs. 70mgkg-1, all respectively. Peak average leachate EDTA concentration was >60mM, yet acclimating soil microflora gradually degraded most all the EDTA. In incubation study, EDDS and EDTA half-lives in acclimated lysimeter media were 5-11days and ≥27days, respectively. It suggests that sustainable phytoextraction of heavy metals is feasible under careful CDI with EDTA (yet not with biodegradable chelants) augmentation at low doses. Despite that the eucalypt was highly salinity (and EDTA) resistant, CDI using RO water further reduces soil solution salinity, thus increasing the usefulness of this remediation technique. © 2014 Elsevier B.V.
Scientific Publication
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