Effects of microbial inoculants combined with maize straw on physicochemical properties and microbial community structure in black soil during soybean growth

Abstract Aim Traditionally, increased crop yield has been supported by applying a large amount of chemical fertilizer. However, using excessive chemical fertilizers on soils diminishes soil fertility and crop yield while contaminating the ecological environment. Method To replace the fertilizer, microbial inoculants, and maize straws were introduced to the soil as environmental fertilizers in this study. During soybean cultivation, their effects on physicochemical properties, enzyme activity, and microbial community structure in the soil were investigated. Compared to fertilization alone, adding microbial inoculants mixed with maize straw (CSF) during soybean cultivation boosted agronomic traits such as soybean fresh weight, plant height, and stem thickness. Result This increased the physicochemical parameters of the soil, such as pH, available Potassium (AP), and water content, affecting the soil bacterial population. Bacteria abundance and diversity significantly increased, with acidobacter, Proteobacteria, Candidatus_ Solibacte, and Sphingomonas dominating. Redundancy analysis revealed that pH and AP were environmental factors that influenced microbial community structure. CSF boosted microbial diversity and community structure while increasing soybean yield from 3.91–5.46%. Conclusion In conclusion, soil improvement using maize straw and composite compound inoculants produced better outcomes. Our findings offer theoretical and experimental references for soil erosion.