Spatial distribution of trace elements in the soils of south-western France and identification of natural and anthropogenic sources

The contamination of soils by trace elements is a major concern for soil quality. This study based on the analysis 356 samples from RMQS monitoring network to establish spatial distribution and origin six (As, Cd, Cu, Cr, Ni, Pb) in south-western region France (area 90,293 km2). An exploratory multivariate statistical analysis, geostatistics combined with geographic information system (GIS) were used identify characterize any concentration anomalies elements. For all studied, shows that there are more this than rest country. Analysis semivariograms spatially auto correlated. structure As highlights anisotropic behaviour direction corresponds gold deposit mining activities region. indicates dual anthropogenic geogenic As. correlation between Cd inherent features calcareous (pH, CaCO3 cation exchange capacity) suggest mainly element; confirmed its associated Jurassic limestone bedrock. correlations Ni clays highlight these elements, as weathered parent material rich also Cr Ni. high Cu concentrations origin, linked viticulture spreading Bordeaux mixture fungicide. Locally Pb automobile emissions large cities