Divergent responses of soil bacterial and fungal community structures and functional groups to secondary succession after rubber plantation abandonment

Background and aims There is still limited knowledge regarding the dynamics of soil microbial community structures and functional groups during forest secondary succession after rubber monocultures (RP) abandonment. Methods Bacterial and fungal communities and functions were investigated for the soil from six forest stands with three replicate plots. Selected stands included an RP, four spontaneous secondary forest stands that formed after RP abandonment at 1 (SF_1), 10 (SF_10), 20 (SF_20), and 40 (SF_40) years, as well as a primary forest (PF, approximately 100 years). Results After RP abandonment, the alpha-diversity metrics of soil microbial communities increased during the first 40 years of succession but decreased in PF. The biomarkers Proteobacteria and Mortierellomycota increased significantly ( P