Yakutin M.V., Andrievskii V.S. 2019. [Peculiarities of parallel successions of microorganisms and oribatid mites in vegetated sands in the subzone of dry steppes of Tuva] // Euroasian Entomological Journal. Vol.18. No.5: 341–347 [in Russian, with English summary].
Institute of Soil Sciences and Agrochemistry, Russian Academy of Sciences, Siberian Branch, Academika Lavrentieva Prosp. 8/2, Novosibirsk 630090 Russia. E-mail: email@example.com, firstname.lastname@example.org
ABSTRACT. As a result of the study conducted in southern Tuva on the vegetated sand ridge Zuger-Eliss, the course of parallel primary successions of soil microorganisms and oribatid mites was analyzed. In the process of the successional changes from the initial embryozem through the light chestnut soil to the chestnut one the synchronous changes in the quantitative parameters of studied pedobionts have been determined. During the succession, the total biomass of microorganisms and the amount of active biomass increases in the upper soil horizon. In the community of oribatid mites the number of species and their abundance increase. These changes in the investigated components of the pedobionts complex occur in parallel, but the pace and character of the transformations or the microbial and oribatid components of this complex are highly specific. Changes in components of the dry steppe ecosystem destruction block during different stages of the successional processes in soil formation in Tyva are uneven, and are most sharply pronounced in the transition from the initial embryozem to light chestnut soil. Quantitative parameters increase in microorganisms up to 4–37 times, and in oribatid mite community from zero to very large values. The transition from light chestnut to chestnut soil at the quantitative level is much less abrupt. Quantitative parameters of microorganisms increase up to 62–73%, and of oribatid mites to 25–40%. Qualitatively, there is a sharp change in the specific activity of soil microbiomass, which may indicate a significant transformation of the microbial complex as a whole. Species structure in the community of oribatid mites is changing in favour of species that are sensitive to extreme environmental factors, which are replacing species with a wider ecological spectra during the succession.
KEY WORDS: South Tuva, vegetated sands, initial succession, dry steppe, soil, microorganisms, biomass, oribatid mites, species richness, abundance.