Cesium Interactions With Illite in the Presence of Bacterial Exudates
Abstract
Biogeochemical processes in the rhizosphere can significantly alter chemical reactions between contaminants and soil minerals. Several strains of bacteria that exude aluminum-chelating compounds were isolated from the rhizosphere of crested wheatgrass (Agropyron desertorum) collected from the Idaho National Engineering and Environmental Laboratory (INEEL). We examined the effect of exudates from the rhizosphere bacteria on cesium desorption from illite. The exudates from some strains of rhizosphere bacteria significantly enhanced Cs desorption from illite. In addition, Cs desorption from illite increased with increasing concentration of exudates from one selected bacterial strain. There was no obvious relationship between Cs desorption and the Al-chelating ability of the exudates. Both mobilization of Al from illite and changes in the density of frayed edge sites on the illite were monitored as a function of exudate type and concentration. Results suggest that exudates from rhizosphere bacteria may play an important role in Cs interactions with illite and, therefore, could alter Cs availability in micaceous soils.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2003
- Bibcode:
- 2003AGUFM.B12D..07W
- Keywords:
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- 0400 Biogeosciences