Bela krajina represents a low karst valley, which is protected by a thick layer of red clay. Basic geological map of Slovenia 1 : 100 000 reports appearance of terra rossa and red bauxite clays in Bela krajina. There is not much data on red soil in Bela krajina, except for one representative profile. The aim of master's thesis is to determine the pedological and geochemical properties of the Bela krajina red soil and its comparison with Bela krajina leached soil and terra rossa in Kras region. Two representative locations were selected for the sampling of red soil (P01, P02), whereas data for two leached and two terra rossa profiles were obtained from Rok Turniški research. A standard pedological analysis was performed at ICPVO Ljubljana, and ICP-MS for major oxides content at Bureau Veritas laboratory in Canada. Samples were also analyzed for free oxide iron (Fed) by dithionite-citrate method. Mann-Whitney test was applied for comparison of red soil to leached soil and to terra rossa. Results showed that red soil contain more clay, Al2O3, Fe2O3, Fed, and has bigger Fed/Fet ratio, less fine silt, total silt, smaller CN ratio, less exchangable Na+ and H+, SiO2, MgO, K2O and smaller molecular ratios SiO2 : Al2O3, SiO2 : Fe2O3 in SiO2 : R2O3. Compared to terra rossa, red soil contain more exchangable Mg2+, Al2O3, Fe2O3, TiO2, Fed, bigger Fed/Fet ratio, less exchangabe Na+ and H+, smaller CEC, less SiO2 and smaller molecular ratios SiO2 : Al2O3, SiO2 : Fe2O3 in SiO2 : R2O3. According to chemical index of alteration (CIA) and chemical index of weathering (CIW) we can conclude that the red soil is the most weathered compared to leached soil and terra rossa. By the intensity of weathering red soil is followed by terra rossa and then by leached soil. Profile P01 is classified as Acrisol, P02 and P06 as Alisols, P03, P04 and P05 as Luvisols.
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