Mikhail Alekseevich Yashin

The paper presents the results of the study of fatty acid profiles of typical chernozems with different management practice. The study showed that degradation of soil organic matter in typical chernozems is accompanied by depletion of fatty acids, while its accumulation resulted in an increase in their diversity. In this regard, the composition of fatty acid soil profiles allows classifying the soil successfully according to the prevailing processes of transformation of organic matter. An uneven distribution of fatty acids was discovered in soil aggregates of different sizes for the untillage chernozems, whereas arable chernozems possessed regular distribution of fatty acids among aggregates of different size. Eicosapentaenoic acid which is a moiety of microalgae, and dihomo-gamma-linolenic acid which is synthesized by fungi Mortierella can be considered as biomarkers of the withdrawal of typical chernozem from agricultural use to a fallow land.