Understanding the (paleo)soils: From paleoenvironmental reconstruction to the role of iron oxides and organic matter on the formation of the surface physicochemical and the aggregation processes

A multi-proxy analytical approach (MPAA) in the investigation of (palaeo)soils that involves a detailed analysis of soil micromorphology, soil physics and chemistry, geochemistry, and bulk and clay mineralogy is crucial for the determination of the palaeoenvironment in which they were formed. The determination of the soil mineral composition and their surface properties that control the formation of soils by aggregation processes is necessary to understand their response to environmental changes (BRONICK & LAL, 2005). Soil aggregation is a complex process, which involves rearrangement of submicron- and micronsized mineral particles into larger clusters by mutual physico-chemical and biological interactions between the mineral surfaces, various organic and inorganic compounds and microorganisms (SIX et al., 2004). Humic compounds are omnipresent in soils and they designate the most important compounds covering the surfaces of the minerals, particularly iron oxides and clay mineral particles (BALDOCK & BROOS, 2012). This lecture aims to demonstrate the significance of MPAA in three different cases, from profile description and palaeoenvironmental reconstruction, to the role of iron oxides and soil organic matter on the formation of the surface physicochemical properties and the aggregation processes. It is based on our previous (DURN et al., 2015; DURN et al., 2017) and current research within the NanoMin project (grant 2504, Croatian Science Foundation).