Approaches to the study of the lithological homogeneity of soil profiles and soil polygenesis

Abstract

A methodology for the analysis and diagnosis of soil polygenesis is discussed. It is based on the suc cessive and complementary stages of soil examination: (1) the field stage, during which the morphological analysis of a soil profile is combined with the study of the spatial behavior of the major soil horizons in order to reveal the degree of their genetic interdependence or their stratigraphic independence and (2) the stage of the careful morphological description of the soil profile at different levels (from the macrolevel to the micro and submicrolevels) by the methods of soil morphology in combination with the methods of paleogeography, mineralogy, cryolithology, microbiomorphology, and other sciences. As a result, we distinguish between the modern and relict (inherited) soil features; the latter are subdivided into the lithogenic soil features (lithorel ics) and pedogenic soil features (pedorelics, traces of the former stages of the soil development). Two groups of models of soil polygenesis can be distinguished: (1) simple models, according to which the changes in the character of the pedogenesis and in the environmental conditions are recorded in the same lithological matrix, and (2) complex models, according to which the changes in the cycles of the soil formation are com plicated by the processes of sedimentation so that they are recorded in the changing lithological matrix.

Quantitative approach to classification of gray forest soils in the Volga-Kama forest-steppe region

“…Dark gray forest soils are moderately differentiated (S = 1.8). This coefficient is calculated assuming the initial vertical homogeneity of parent materials as estimated by the ratios of medium sand to fine sand and of the total sand content to the content of the coarse silt fraction in the soil horizons [21,[25][26][27]33]. Statistically significant differences were found for the humus contents in the upper (humus) horizons of the three subtypes of gray forest soils.…”

Evolution of forest pedogenesis in the south of the forest-steppe of the Central Russian Upland in the Late Holocene

“…Paleosol and paleoenvironmental reconstructions were based on the comparative analysis of the properties of buried paleosols of different ages and their modern surface analogues that continued their development near the ramparts under similar geomorphic conditions (level or slightly inclined (<2°) interfluve surfaces near steep slopes of river valleys and balkas). Our study was based on the genetic analysis of the soil profiles with identification of the particular characteristics of the polygenetic nature of the studied soils [31].…”