Influence of fresh biological chicken droppings on the microbiological indicators of low-productive soddy podzolic soil

The article presents fresh biological dropping of caged chickens in crop production. After a thorough study of its environmental friendliness to the environment, this new biological dropping will reduce the cost of poultry farms for the disposal of dropping and use for more efficient cultivation of crops on marginal lands. The experiment used a high dose of organic matter - 120 t/ha, applied by spreading (control - without fertilisers). Sequencing of the metagenomes of soil samples showed that the soil microbiome’s phylogenetic composition was preserved due to the introduction of bacterial-fermented probiotic dropping. The authors also note that its taxonomic structure and functionality changed due to increased bacteria (with the different activity of taxa). Thus, the authors report an increase in the abundance of bacteria in the 1st sampling period from 6.9•107 to 1.3•108 copies/g of the soil of the 16S rRNA gene of bacteria in the plough horizon, and after 30 days - from 1.6•107 to 1.3×108 copies/g. For these purposes, opportunistic and pathogenic microorganisms in the fertilised soil found in all soil samples were also studied. A higher proportion of enterobacteria was noted in the control sample (0.6%), and with dropping, it did not exceed 0.15%. The content of pathogenic bacteria on a fertilised background in the 1st period of soil sampling practically did not change (0.7–0.8%), but in the 2nd period, it decreased sharply (from 2.5 to 1.1%). However, the authors note a decrease in the content of pathogenic bacteria. This decrease was accompanied by an increase in their abundance (from 3.9•105 to 1.4•106 copies/g), mainly Pseudomonas sp bacteria (from 2.1•105 to 9.3•105 copies/g), which is a consequence of a general increase in the abundance of bacteria in the microbiome against the background of enrichment of the soil with organic matter and an increase in soil fertility. The authors did not reveal a significant negative microbiological effect after the action of fresh biological chicken dropping on the soil’s ecological state at the specified research stage.