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Partitioning of metals in soil particles of various size classes has been receiving greater significance due to the necessity to predict the behaviour and pathways of the potentially toxic elements in the environment. In this study the analysis of metals’ distribution in various particle size fractions was performed to characterize and compare geochemical features of the topsoil horizons of two small erosional landforms located in uncontaminated area of the central part of European Russia (the Middle Protva basin, mixed forest zone). The landforms represent two typical lithological types of gullies in the study area. Soil samples were fractionated and the concentrations of Fe, Mn, Ti, Zr, Ni, Co, Cr, Zn, Cu, Pb were determined in five particle size fractions: 1–0.25, 0.25-0.05, 0.05−0.01, 0.01–0.001 and

For an improved understanding of metal behavior in soils, studies on geochemical changes occurring in a specific grain-size fraction during pedogenesis and lateral translocation of soil material are needed. In the present research we analyzed the concentrations and vertical distributions of Fe, Mn, Cu, Ni, Co, Cr, Zn, Pb, Ti, Zr in coarse and medium sand fraction of the major soil types of the middle Protva basin, situated in the mixed forest zone of European Russia, and described patterns of downslope (lateral) distribution of metals in the humus horizons along two catenas and two types of small erosional systems. The observed concentrations for all metals in the fraction 1–0.25 mm, except of Mn, conform to the natural geogenic concentrations reported previously in literature. The majority of the metals exhibit high natural variability in concentrations in the sand fraction. Higher metal concentrations are found either in the topsoil horizons or in parent material and underlying stratum. Studying lateral aspects of metal distribution in the sand fraction of humus horizons revealed a decrease in Mn, Zn, Pb, Co, Ti and an increase in Fe, Cr and Ni levels of the lower sections of the slopes. The similarity of metal concentrations in the sand fraction in these positions across two catenas implies the importance of the geochemical convergence processes operating in downslope direction. The small erosional landforms, a gully and a dry U-shaped valley, show similar patterns in lateral distribution of Fe, Cu, Ni, Cr, Zr, Zn, but they differ in terms of Pb, Co and Mn behavior across their elementary units: adjacent areas, slopes and bottom. The results imply that the features of vertical (within the soil profiles) and lateral (along catenas and small erosional systems) distributions of metals are significantly controlled by the provenance of the sand fraction, although at the same time some variations in metal contents seem are attributed to chemical transformations of the sand fraction due to pedogenic processes and during downslope translocation of soil material.