Organic management practices shape the structure and associations of soil bacterial communities in tea plantations

Abstract

Crop management practices can strongly affect soil microbial communities and their ecosystem services, but it remains unclear how these effects extend to different agroecosystem contexts, such as in tea plantations. A comparison of paired tea plantations (organic vs. conventional managements) in Eastern China was conducted to investigate the ways in which agricultural management can affect soil physicochemical parameters, composition, diversity and assembly of soil bacterial communities. Compared with conventional management, organically managed tea plantations on average increased soil microbial C by 164.4% and soil microbial N by 482.9%, respectively in Wuyi and Xiangshang sites. The results of 16S rRNA pyrosequencing analyses revealed that the diversity and richness of bacterial communities was similar under both managements, but the structure of soil bacterial communities was significantly reshaped by the management type (R2 = 0.410, p < 0.01) used in the tea plantation as well as geographical origin (R2 = 0.268, p < 0.01). Co-occurrence network analysis uncovered that organic management weakened the connectivity among soil bacteria taxa in tea plantations, indicating more stable microbial associations under conventional management practices. These results emphasized the importance of management and geological origins in reshaping soil bacterial structures in tea plantations.