Newly formed riparian microhabitats simplify bacterial community structure and diversity

Purpose Microorganisms have a multidimensional influence on plants, and they play pivotal roles in the soil-root interface mechanism. However, little is known about microorganisms for plants in the riparian environment regarding the endosphere, rhizosphere, and bulk soil. Therefore, this study assessed rhizodeposition, the structure of bacterial communities, and the assembly processes among the endosphere, rhizosphere, and bulk soil. Methods Salix matsudana , Taxodium distichum , Cynodon dactylon , and Hemarthria altissima were investigated in the riparian zone of the Ruxi River, China. We collected rhizospheres, bulk soil, and roots for these plants and analyzed the soil’s physico-chemical properties, enzyme activities, bacterial community complexity, and assembly processes. Results The results showed different abundant bacterial communities in the rhizosphere, bulk soils, and roots. Rhizodeposition of nitrogen and phosphorus had the greatest impact on bacterial diversity. Bacteria had more positive relationships in the endosphere than in soil compartments, indicating a relatively complex and stable community structure. The stochastic processes shape the microbial geographic variation of the endosphere, rhizosphere, and bulk soil for selected plants, with the proportional contribution in the rhizosphere and bulk soil being significantly less than that in the endosphere. Different microhabitats, via the assembly process, shape bacterial community structures. Conclusions We discovered that the bacterial community in the endosphere was less affected by environmental factors and more stable than the bacterial community in the soil compartment. This will help us find the best ways to keep soil and water safe in the newly formed riparian zone and understand the ecological evolution of microbes for vegetation restoration.