Iron oxides in four Red Mediterranean soils on metarhyolite and metadolerite in Kilkis, Greece

Abstract

The various iron fractions were quantified by selective dissolution (Fe_d, Fe_o, Fe_t) in four Red Mediterranean soils, developed on metarhyolite and metadolerite. They were similar in all profiles. A strong trend of iron removal from the surface horizon and of its subsequent illuvial translocation to the argillic horizons was observed. In all profiles, Fe_o was not related to the organic matter content indicating the Mediterranean xeric soil environment. The Fe_o/Fe_d ratio and the percentage of crystalline iron oxides (Fe_d-Fe_o) suggested that the pedoenvironment in which the profiles P1, P2 were formed, allowed the high crystallization of iron oxides. As indicated by the Fe_d/Fe_t values, the weathering process was more intense in the metarhyolite-developed soils. In contrast, the metadolerite-developed soils present conditions of poorly crystallized iron oxides and a lower degree of development.

Keywords:

• Red Mediterranean soils
• iron oxides
• parent rock
• degree of soil development

Acknowledgements

We would like to thank the Greek State Scholarships Foundation (I.K.Y.) for the financial support to P. Tsaousidou.