Effects of flooding in southern Poland on heavy metal concentrations in soils

Abstract

. Total concentrations of heavy metals in soils were measured before and after the catastrophic floods of 1997, which devastated most districts within the commune of Raciborz in southern Poland. The assays covered lead, zinc, cadmium, chromium, nickel and copper. Analyses on soil samples taken in 2002, after the floods, were compared with those of 1992, taken as part of regular monitoring. There was an increase in the mean concentrations of heavy metals as a consequence of the flooding. Only a small part of this increase may be due to changes in the method of analysis between the two dates. The mean concentrations of heavy metals after flooding did not exceed the permissible levels for Polish soils. Permission was therefore granted to continue using much of the flooded land for farming. However, the investigations located a number of places where heavy metals were above permissible levels. Some of these were a consequence of the floods, but others were considered to be due to contamination from previous industry. Where high concentrations were found, land was excluded from agricultural use.