GEOC 7 |
| Lu Zhao, Rainer Schulin, and Bernd Nowack. Institute of Terrestrial Ecology, Swiss Federal Institute of Technology (ETH), Grabenstrasse 3, CH-8952 Schlieren, Switzerland |
| The leaching of heavy metals from polluted soils is a serious problem and the soil solution is the key point to investigate as the carrier of mobilized and transported heavy metals. The traditional methods to obtain soil solution rely on the extraction of soil samples and cannot give a direct view of what happens in the soil. This study investigates the mobilization and transport of heavy metals in a soil column at different water flow rates. Seven suction cups have been installed in the 25cm-thick topsoil to obtain soil solution directly. The columns are irrigated with artificial rainwater and are operated under unsaturated water flow conditions. Total metals (Zn and Cu) as well as their speciation (free Cu2+ and labile Zn) are measured in addition to general chemical parameters. The mobilization of Cu is coupled to a slow mobilization of DOC. The strong dependence of Zn mobilization on the flow-rate indicates the importance of slow mobilization reactions. |
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Chemistry of Metals in Terrestrial and Aquatic Systems
8:00 AM-11:25 AM, Sunday, March 28, 2004 Marriott -- Marquis NE, Oral
Division of Geochemistry |