Objective The large-scale plantation of Camellia oleifera forestry is a typical mode for the comprehensive management of rocky desertification in northern Guangdong with good economic benefits. However, the effects of planting years of Camellia oleifera forestry on soil microbial communities in karst areas are still unclear.

Method Based on soils with planting years of 2, 3, and 7 of Camellia oleifera plantation from Fushushan planting base in Lechang City of Guangdong Province , high-throughput sequencing and molecular ecological network analysis methods were used to analyze the soil bacterial community dynamic.

Result The increase in planting years of Camellia oleifera could promote the accumulation of soil ammonium and total nitrogen contents. Although the community diversity of soil bacteria did not change significantly with the increase of planting years, significant variation was observed on bacterial community composition. Moreover, soil moisture content was the key environmental factor affecting soil bacterial community under Camellia oleifera forestry with 2 and 3 years, while soil bacterial community under Camellia oleifera forestry with plantation of 7 year was mainly affected by pH. In addition, compared with Camellia oleifera forest planted for 2 and 3 years, the soil bacterial taxa in the camellia oleifera forest planted for 7 years were more closely connected, but at the same time, there was a lack of modularity of the bacterial network and the evolution of key species.

Conclusion This study reveals the dynamic characteristics of soil bacterial community with different planting years of Camellia oleifera in rocky desertification area of northern Guangdong, which provides a theoretical basis for the practical management in maintaining the soil ecosystem function of Camellia oleifera forestry.