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Metal leaching along soil profiles after the EDDS application--a field study
Aiguo Wang1, Chunling Luo, Renxiu Yang
1College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
Environmental Pollution (Barking, Essex : 1987)
|February 28, 2012
Summary
Chelant-enhanced phytoextraction using biodegradable ethylenediaminedisuccinic acid (EDDS) showed increased soluble metals in topsoil initially. However, metal leaching was limited and decreased over time, suggesting controlled field conditions.
Area of Science:
- Environmental Science
- Soil Science
- Biogeochemistry
Background:
- Chelant-enhanced phytoextraction aims to increase metal uptake by plants.
- A key concern is the potential for metal leaching into deeper soil layers or groundwater.
Purpose of the Study:
- To evaluate metal leaching in soil profiles after applying the biodegradable chelant EDDS.
- To assess the short-term and medium-term effects of EDDS on metal mobility in soil.
Main Methods:
- Field study assessing metal leaching over 36 days after EDDS application.
- Analysis of soil metal speciation and competition with calcium (Ca).
Main Results:
- EDDS transiently increased soluble copper (Cu) and zinc (Zn) in the top 5 cm of soil.
- Increased metal solubility was generally confined to the top 20 cm of the soil profile.
- Metal-EDDS complexes were identified, with Ca as a major competitor for EDDS.
Conclusions:
- Soluble metals decreased rapidly over time, with no significant differences in extractable Cu observed after 22 days.
- The potential for metal leaching with biodegradable EDDS can be managed under field conditions.
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