Abstract
Spatial distributions of fifteen trace elements (As, Be, Cd, Co, Cr, Cu, Mo, Ni, Pb, Sb, Sn, Tl, U, V, and Zn) potentially harmful for the human health and the ecosystem have been studied in the soils of Catalonia. Geographic Information Systems were used together with the cartographic information available in sampling design. Descriptive statistics, box-plots, and cumulative distribution figures were used to assess the differences in trace element concentrations among soil uses. A clear enrichment in Pb and Sn (mean 24.3 and 3.31 mg · kg−1 d.w., respectively) in urban soils was observed when compared to other soil uses. Values obtained for country soils where similar to those observed in previous studies carried out in Europe. Trace element enrichment or impoverishment observed in the soils is consistent with the concentration in representative rock types of the underlying geology analysed in other areas. This fact indicates that geology is an important factor influencing trace element distribution in country topsoils of the region studied. Background and reference values, computed as upper confidence limits for a central tendency value and 95th percentile, respectively, were also provided to assist in the assessment of soil pollution in the region.