Map of the Natural Fund on scale 1:250,000 of the Emilia-Romagna plain — Nichel [Ni]

Represents the distribution of the area in the subsoil (90-140 cm depth) of the nickel content in agricultural soils. This depth is considered representative of the natural background content (‘pedo-geochemical content’ according to ISO/DIS 19258, 2005). The cartographic units are represented by groups of polygons belonging to concentration classes. The factors that regulate the natural content of metals in soils are: origin of the sediment in which the soil was formed, weaving, and evolutionary degree. For nickel as well as for chromium, the dominant factor is the origin of the sediments that originate the soil. The map has an original approach in that it uses genetic-environmental interpretation for the assessment and geographical extension of the geochemical data, instead of the more traditional geostatistic analysis. The concentration values are obtained by the analytical method XRF (X-ray Fluorescence Spectrometry) in order to determine the total content.