Changes in the microbiome of small solonetz under the influence of long-term cultivation of sweet clover

Riksen V. S., Korobova L. N., Lomova T. G.

The article presents the results of a five-year study of plant-microbial interactions in small solonetz in the Barabinsk lowland of Siberia where yellow sweet clover was cultivated in the fodder crop rotation for 33 years. The phytomeliorative effect of the sweet clover was manifested in the desalting of the small solonetz and replenishment of the nitrogen fund of the soil. Under the sweet clover at the layer of 0-20 cm, the oligotrophy of the soil decreased by more than two times and the microbial transformation of plant residues into humus compounds became two times more active. The prokaryotic microbiome became somewhat more diverse; the number of orders and families of bacteria and archaea, as well as their genera, increased to 387 against 311 in virgin soil. The influence of the sweet clover changed the metagenome of the small solonetz at the level of phylum and classes, selecting it towards the representation of copiotrophs that play a significant role in the carbon and nitrogen cycles.

Keywords:small solonetz, phytomelioration, yellow clover, soil microorganisms, microbiome, taxonomy.