The accumulation of copper in soils of the Italian region Emilia-Romagna

The investigation was carried out in 2005, on 30 plots chosen in the Central-Eastern part of the Emilia Romagna region, and cultivated with pear, grapevine and vegetable crops under the organic management system. For each crop, 5 plots with a level of calcium carbonate > 10% and 5 plots with a level of calcium carbonate < 3% were selected. For pear and vine, soil analyses were performed at the depths of 0-20 cm and 20-50 cm, for vegetable at the depth of 0-50 cm. Organic matter content was higher in pear-cultivated plots, followed by grapevine and vegetable crops. Copper application rate, from 1998 to 2004, was higher in pear and grapevine than in vegetable plots. Soil total and DTPA-extractable Cu were higher in pear and grapevine than in vegetable-cultivated plots. Soil DTPA-extractable Cu concentration was higher in the upper horizon than at 20-50 cm soil depth. The increase of total Cu in pear and vine-cultivated plots was combined with the increase of soil inactive Cu.