Kallas E.V., Nikitich P.A.
CONSERVATION INFORMATION ABOUT PEDOGENESIS IN HUMUS PROFILES OF SOILS ^{[№ 10 ' 2015]}
The soil integrally reflects and records the action over time of all factors of pedogenesis in its properties and performs a global function in the biosphere — the information. One of the most reliable memory carriers is soil humus, which structure remains in the soil for a long time. The humus soil profile is a kind of "archive" that holds the encrypted information about the evolution of the environment at different stages of the soil formation. Humus profiles as carriers of "soil memory" are considered through the example of soils of the Tom-Yaya watershed. Humus profiles of grey forest soils developed in the taiga–forest-steppe ecotone, reflect the complex contrasting evolution due to the displacement of landscape boundaries in the Holocene and leading to different stages of pedogenesis — change the steppe (meadow ) of the type of soil on the forest. The steppe (meadow) soil type replacing the timber soil type is reflected in the profile as a second humus horizon sharply different in the composition of humus from up- and under-lying areas of the humus profile. In particular this layer has a high accumulation of humic acids and calcium humates, a significant decrease in fulvic acids and extension of the relation Cha:Cfa to 2 or more units, which is typical of black earth soils and meadow-chernozem type of soil formation. On chernozem (meadow-chernozem) soil types, grey forest soils were formed in the Holocene Optimum, as evidenced by radiocarbon age of humic acids (3 750 years). It is shown that humus profiles reflect the characteristics of the evolution of soil and store in their properties and structure the information about the change in environment during the period of formation of the soil body, and therefore can serve as a "tool" for the reconstruction and used for modelling the behaviour of soils in the future.