Quantitative diagnostics of soils varying hydromorphy degrees of one-loess terraces of rivers in the Forest-Steppe of Ukraine

The article specifies the features of humus accumulation in the soil profiles of one-loess terraces in order to clarify their classification belonging. The objects of the study were soils of varying degrees of hydromorphism on one-loess terraces of river's left-bank on the territory of Sumy, Poltava and Kharkiv regions within the limits of the Forest-Steppe of Ukraine. Methods of research: traditional field description of soil morphological characteristics; analytical determination of the total content of humus, content of granulometric fraction <0.01 mm (physical clay) and exchange cations; calculations of the parameters of humus accumulation and humus redistribution in the soil profile by the coefficients of profile accumulation of humus (CPAH), relative accumulation of humus (СRAH) and regression of organoprofile (CROP); field observations of groundwater seasonal ripples by wells. It is shown that the polygenetic nature of the soils in one-loess terraces is due to the specific dynamics of soil formation factors. The influence of the groundwater pulsing level on the soil morphogenesis and the intensity of humus accumulation have been determined. The expediency of application of parametrizated estimations in the diagnostics of soils with discussion genesis has been proved. The identified of podzolization processes in semihydromorphic and hydromorphic soils based on content and distribution of exchange cations in profile as a consequence of the periodic settlement of forest vegetation on the territory of first-loess terraces. As a result was clarifscation the genetic status of the soils of one-loess terraces and establishment of their belonging to the overtypical and typical levels of the pedosphere organization.