Soil microbes and oxygen influence the changes in bacterial community composition during swine carcass decomposition
Abstract Background Carcass decomposition is influenced by various factors such as temperature, humidity, microorganisms, invertebrates, and scavengers. Soil microbes play a significant role in the decomposition process. In this study, we investigated the changes in the bacterial community during carcass decomposition in soil with an intact microbial community and soil which was sterilized decomposed with and without oxygen access using 16s rRNA metagenomic sequencing. Results Based on the 16S rRNA metagenomic sequencing, a total of 988 operational taxonomic units (OTUs) representing 16 phyla and 533 genera were detected. The bacterial diversity varied across the based on the alpha diversity indices. The bacterial composition in the unsterilized soil – aerobic condition (U_A) and unsterilized soil – anaerobic condition (U_An) set-ups have higher alpha diversity than the other burial set-ups. Beta diversity analysis revealed a close association in the samples according to the burial type and decomposition day. Firmicutes was the dominant phylum across all samples regardless of the burial type and decomposition day. The bacterial community composition changed throughout the decomposition process in all burial set-up. Meanwhile, the genus Bacillus dominated the bacterial community towards the end of decomposition period. Conclusions Our results showed that bacterial community composition changed during carcass decomposition and was affected by the soil and oxygen access, with microorganisms belonging to phylum Firmicutes dominating the community.