Aging effect on the copper sorption on a vineyard soil: column studies and SEM-EDS analysis.

The uptake of copper by a vineyard soil in fixed bed column systems was investigated in order to study the influence of the aging time on the soil retention capacity. The application of copper by means of several additions, as in field conditions, increases the retention capacity of the soil relative to a single one application of the metal. The aging effect is responsible for this phenomenon, since its increase enhances the amount of adsorbed copper. Moreover, aging the soil reduces the amount of available copper during a Ca(NO(3))(2) leaching of the soil columns which suggests a redistribution of a weakly-bound copper fraction to a more strongly-bound fraction. Scanning electron microscopy combined with energy dispersive X-ray spectroscopy (SEM-EDS) indicates that copper is heterogeneously distributed within the soil sample. Nevertheless, copper is preferentially associated with fractions containing Fe and Al atoms.