Geochemistry of serpentine agricultural soil and associated groundwater chemistry and vegetation in the area of Atalanti, Greece

• The geochemistry of serpentine soil at Atalanti, Greece was studied.
• The impact of ophiolitic rocks on soil, groundwater and vegetation was evaluated.
• Weathering intensity of parent rock affects the soil enrichment in Cr, Co, and Ni.
• Mobilization processes of ophiolite derived elements define groundwater chemistry.
• The Ni hyperaccumulator Alyssum chalcidicum plant species was identified.

The soil geochemistry was studied in the area of Atalanti, Greece, an area characterized by presence of mafic and ultramafic rock members of an ophiolite complex. The objectives of the study were to evaluate their impact on soil chemistry and to establish the geochemical baseline of soil with respect to elements derived from the ophiolite rocks. A total of 118 agricultural soil samples were collected and found to be enriched in Ca (7.6%), Co (31 mg/kg), Cr (230 mg/kg), Cu (37 mg/kg), Mg (2.9%) and Ni (330 mg/kg) relative to the median values of both European and Greek soils. Soil baseline concentrations of the ophiolite derived elements (Cr, Ni, Co) were estimated within two sub-areas and the variation in their concentration was assessed along two toposequences characterized by different intensities of weathering of parent rock. Differences in groundwater chemistry were also demonstrated for the aquifers developing within the two subareas. The results of this study can be utilized in future studies on serpentine soil in temperate climate by providing an objective basis for setting realistic threshold values for pollution assessment and remediation.