Features of the Mineralogical Composition of Coarse Fractions and Their Correlation with the Genesis and Properties of Soils at the Zvenigorod Biostation of Moscow State University

摘要

The study of the mineralogical composition of sand (0.25–0.10 mm) and coarse silt (0.10–0.05 mm) fractions revealed a significant lithological heterogeneity of soil-forming material in the area of the Zvenigorod Biostation. The domination of ore minerals in heavy fractions (to 42% of grains) and, to a smaller rate, of hornblende and biotite, explains iron accumulation in soil profiles and the brown color of sandy loam soils. This feature, along with the insignificant presence of the clay fraction, enables us to assign texturally undifferentiated soils to the division of iron-metamorphic soils and more differentiated soils to the division of eluvial soils.