5. Conclusions
According to the results of the present study, pH value and TP content were key soil environmental factors driving variation in rhizosphere fungal and bacterial β-diversity, respectively, during the restoration of R. pseudoacacia plantations. Meanwhile, soil NH4+-N content influenced both bacterial and fungal β-diversity in the rhizosphere of R. pseudoacacia . With an increase in forest age, rhizosphere microbial communities tended to adjust their survival strategies, at the phylum level. Compared to the fungal community network, the bacterial community network was more stable. In addition, the bacterial network was more complex, with higher connectivity than the fungal network. The microbial networks had better aggregation in the nearly-mature and mature forests (15 and 25 years old), and in the over-mature forests (35 and 45 years old). Fungi, but not bacteria, had specific lineage changes in the course of R. pseudoacacia forest restoration. Furthermore, the results of the present study demonstrated the influence of soil multifunction on microbial network modules, and the importance of core microbiota diversity in rhizosphere soil multinutrient cycling activities under R. pseudoacacia plantations.