Addition of Chicken Litter Compost Changes Bacteriobiome in Fallow Soil

Abstract

Composting is an environmentally friendly process, turning animal waste into fertilizer. Chicken litter compost (CLC) improves soil properties, increasing crop yields. However, the CLC effect on the soil microbiome is understudied. This study aimed to compare bacteriobiome diversity in fallow arable Chernozem with and without CLC addition in a field experiment in the Novosibirsk region, Russia, using 16S rRNA gene metabarcoding. Pseudomonadota, Actinomycetota and Acidobacteriota were the most OTU-rich phyla, together accounting for >50% of the total number of sequence reads. CLC-related shifts in the bacteriobiome structure occurred at all taxonomic levels: the Bacillota abundance was 10-fold increased due to increased Bacilli, both being indicator taxa for the CLC-soil. The main Actinomycetota classes were the indicators for the CLC-soil (Actinobacteria) and no-CLC soil (Thermoleophilia, represented Gaiella). Both Bacillota and Actinomycetota phyla were the ultimate constituents of the CLC added, persisting in the soil for five months of fallowing. The no-CLC soil indicator phyla were Acidobacteriota (represented by Acidobacteria_Group3) and Verrucomicrobiota. Future metabarcoding studies of chicken litter application in agricultural soils, including cropped studies, should address the soil microbiome at the species/strain levels in more detail, as well as how it is affected by specific crops, preferably accompanied by a direct methodology revealing the microbiota functions.