Rare microbial populations as sensitive indicators of bacterial community dissimilarity under different agricultural management practices

ABSTRACT

Revealing the composition and role of rare and abundant microbial groups is crucial to understand ecosystem processes and function. In 2018, we characterized soil bacterial community, abundant (AMPs) and rare microbial populations (RMPs) with mineral fertilizer and mineral fertilizer combined with straw return under continuous maize (Zea mays L.) and soybean (Glycine max Merr.)-maize rotation systems in a Mollisol in Northeast China. The results showed that the effects of fertilization on total bacterial community, AMPs and RMPs were greater than cropping systems. The cropping systems had a stronger effect on α diversity of bacterial community than fertilization. The RMPs accounted for 50.1% of the relative abundance and contributed 64.3% to the community dissimilarity. The RMPs accounted for 96.7% of the amount of operational taxonomic units (OTUs), thus became the most important contributors to community diversity. The OTUs with lower relative abundance had a narrower niche range, indicating that rare OTUs were more easily affected by habitat uniqueness. The RMPs were important contributors to chemoheterotrophs and were more closely correlated with variations in soil functions than AMPs. Our results provided deep insight into the ecological role of RMPs, which is useful for rational management and improving agricultural ecosystem sustainability.

KEYWORDS:

• Agricultural practices
• bacterial community
• black soil
• indicator
• rare microbial populations

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was funded by the Research Program of Frontier in Sciences of the Chinese Academy of Sciences (ZDBS-LY-DQC017) and the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA28010301).