Changes of bacterial community in arable soil after short-term application of fresh manures and organic fertilizer

The application of animal manure is highly recommended in agricultural production. However, the effect of different kinds of manures on bacterial community in farmland still remains unclear. In this study, a short-term field experiment was conducted to investigate the rapid effects of pig manure (PM), chicken manure (CM) and organic fertilizer (OF, composted by pig manure) application on soil physicochemical properties and soil bacterial community. The results showed that the application of CM and OF significantly increased soil bacterial richness (p < 0.05), mainly correlated with the increase of soil total nitrogen. Compared with CM and PM, OF had the greatest disturbance to soil bacterial structure. And total phosphorus showed the highest correlation with bacterial community. Meanwhile, the application of OF reduced the relative abundance of Actinobacteria, the organic matter synthetic bacteria, and Nitrospirae, the nitrifying bacteria, by 17.18% and 40.00%, respectively. 16S functional prediction analysis results shows that the application of OF increased the relative abundance of genes encoding Ribulose-1,5-bisphosphate carboxylase/oxyg (RuBsiCO), the genes involved in soil Calvin cycling, by 20.51%, and increased the relative abundance of genes encoding nitrous-oxide reductase by 44.86%. In conclusion, Short-term application of OF had greater disturbance to soil bacteria than CM and PM, and it had a significant influence on soil functional bacteria and genes involved in soil carbon and nitrogen cycling.