Soil variability of denudation landforms on eluvium and diluvium of Devonian red rocks (Lake Belyo basin, Republic of Khakassia, Russia)
E.Yu. Konstantinova, A.O. Konstantinov, A.A. Novoselov
Lithological heterogeneity and dissected relief are the main factors that determine trends of soil development and diversity of soil cover within cuesta ridges and slopes of the Lake Belyo basin (Republic of Khakassia, Russia). Hyperskeletic Mollic Leptosols on eluvium of bedrock are predominant within the eluvial landscape position of local watersheds and upper parts of slopes. These soils have a shortened profile and an incomplete set of genetic horizons. Leptic Petrocalcic Chernozems (Endosalic) form on eluvial-deluvial rocks in the eluvial-accumulative positions of local depressions whereas Calcic Chernozems (Endosalic) occupy the transeluvial-accumulative positions of gently sloping lower part of the macroslope of the lacustrine basin. Less developed soils (Leptosols) have a reddish color, small thickness of humus horizons with rather high content of organic matter and high alkalinity of the entire profile with a close bedding of dense calciferous rocks. Chernozems differ by the nature of underlain sediments. Slight sulfate-chloride and sulfate salinization of the profile, which does not hinder the development of vegetation, is typical for these soils. Relatively small thickness of humus profile is characteristic for the studied Chernozems. Humus accumulation in the upper part of the profile turns into sharp decrease in the content of organic carbon with the depth. The presence of soils with different degrees of development on corresponding surfaces reflects certain stage of denudation alignment of elevated forms of relief. Leptosols and Chernozems are different parts of single evolutionary series of soils in a context of continuous translational process of physical weathering within the macroslope of the lacustrine basin. Although Leptosols gradually change to Chernozems at the mesolevel of the entire macroslope, there are areas within the aerials of Chernozems where less developed soils form on fine-grained sediments, which complicates the structure of the soil cover of the whole territory.