The effects of biochar amendment and organic fertilizer on soil properties and microbial communities of wheat rhizosphere soil in the Yellow River Delta

Biochar amendment and organic fertilizer has been used as an effective practice to improve soil fertility. However, the response of microbial community after biochar amendment and organic fertilizer application has not been thoroughly elucidated especially in saline-alkali soil. This study investigated the microbial community variation of wheat rhizosphere soil after different amounts of biochar amendment and organic fertilizer application in the Yellow River Delta (China) by Illumina MiSeq amplicon sequencing. The results showed that medium organic fertilizer application significantly decreased the diversity of bacteria in saline-alkali soil, while the fungi diversity had no evident changes between the six treatments. Proteobacteria and Actinobacteria were the dominant bacterial phyla, simultaneously the dominant fungal phyla were Ascomycota and Mortierellomycota found in the rhizosphere soil. Furthermore, redundancy analysis indicated that the changes in bacterial communities are associated with soil properties pH, available phosphorus and total phosphorus, while pH and AP were crucial contributors in regulating the fungi distribution. The research provides a reference for the rational use of biochar amendment and organic fertilizer in saline-alkali soil.