For over a century, ecologists have pondered how biological communities assemble and change after disturbances, a process known as ecological succession. Yet, understanding these changes for soil microbes - the most abundant organisms on Earth - has remained a challenge. 

"The complexity and diversity of soil microbes have made it incredibly difficult to discern their global successional patterns and drivers," explains Professor ZHANG Kerong, lead researcher from the Wuhan Botanical Garden of the Chinese Academy of Sciences. “we' ve now find evidence for the universality for microbial community convergence during succession regardless of the successional types and initial conditions.”

Analyzed the raw sequencing data from over 5000 soil samples collected globally using a uniform bioinformatics analysis pipeline, researchers tracked the microbial succession after natural or human - caused disturbances. 

They observed a strong tendency for convergent succession despite the successional types and initial conditions. The convergence is indicated by the decrease in compositional dissimilarity between communities with successional age. The convergent succession is driven by directional species replacement, directly linked to the changes in soil properties.

“This study highlights the key mechanisms shaping microbial succession are dynamic over time” says YU Zhi, the first author. “In early succession, the soil microbial β - diversity (β - total, compositional dissimilarity between communities) was primarily driven by species addition, while β - diversity becomes increasingly governed by species replacement with succession.”

This research fills the knowledge gap in our understanding of soil microbial succession patterns and drivers, and highlights the universality of community convergence as predicted by the classical macroecological model.

Results haven been publish in Global Change Biology entitled“Patterns and Environmental Drivers of Soil Microbial Succession”. It was supported by the National Natural Science Foundation of China and Youth Innovation Promotion Association CAS.

Change patterns of β - diversity and its components of bacterial and fungal communities over succession (Image by WBG)