• Marina Gatti Institute of Agricultural and Environmental Chemistry, Università Cattolica del Sacro Cuore, Piacenza
  • Anna Flora Campanale Institute of Agricultural and Environmental Chemistry, Università Cattolica del Sacro Cuore, Piacenza



heavy metals, extraction unique, urban soil, pinewood soil, pollution


Three location types with of different environmental impacts were considered in the district of Ravenna, a city park, a suburban pinewood and arable fields. In this paper we report the preliminary results about the relationship between land use and soil management with chemical fractionation of heavy metals. The distribution and solubility of Cr, Ni, Cu, Zn, Cd and Pb was determined by water and LMWOAs extraction procedures in horizons A1 and A2 of 13 soils. In general the maximum potentially toxic element concentrations were associated with soil collected from the pinewood, and they tended to decrease with depth.

The upper layer enrichment of the pinewood soils clearly revealed an anthropogenic origin of pollution. Under the pinewood, the extraction power by the single extraction procedures showed a pattern quite similar in terms of ranking of metals extracted, except that Zn and Ni were more dissolved than Cu by the use of LMWOAs. Under the pinewood, the metal levels presented a rather similar distribution pattern in terms of ranking of extractive power by the single extraction procedures, with Zn and Ni being more dissolved than Cu by the use of LMWOAs extractant. However, both readily available pools were demonstrated to be more enriched in Ni, Zn, Cd and Pb compared those of city park and arable soils. City park and arable soils had high contents of  Cu. The highest concentrations were particularly shown by the arable soil under orchard, due to frequent fungicide applications. Single extractions were compared to metals dissoved in aqua regia by bivariate correlations.

By comparison, pinewood soils showed higher positive relationships between pseudo-total contents determined by aqua regia and metal concentrations from single extraction procedures than city park and arable soils. The highest correlation coefficients were found for Zn and Cd by water extraction, and for Cu and Pb by LMWOAs extraction. Both water and LMWOAs pools exhibited poor correlation with pseudo-total contents of Cr and Ni.


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How to Cite

Gatti, M., & Campanale, A. F. (2009). PRELIMINARY RESULTS ON THE DISTRIBUTION AND SOLUBILITY OF HEAVY METALS IN URBAN AND SUBURBAN SOILS OF RAVENNA. EQA - International Journal of Environmental Quality, 2(2), 47–57.