Co-occurrence network of bacterial communities in mollisol soils under increasing hydrothermal conditions

Abstract:

Mollisol soil is one of the soil types with high content of organic matter and fertility, climate change will significantly change the structure and potential interactions of mollisol soils microbial communities. [Objective] This study is aimed to explore the microbial community structure and succession characteristics of mollisol soils under increasing hydrothermal conditions. [Methods] Based on a soil transplantation expriment, 16S rRNA high-throughput sequencing was used to analyze the bacterial community structure of mollisol soils (in-situ, warming1 and warming2); CoNet was used to construct the microbial co-occurrence networks and identify the hub microbes, structural equation models and correlation analysis were used to explore the direct and indirect relationships between soil properties, microbial co-occurrence networks, and diversity under the increasing precipitation and temperature conditions. [Results] We found that mollisol soils were dominated by Verrucomicrobia, Proteobacteria, Acidobacteria, and Actinobacteria. Soil transplantation simulating climate change altered the patterns of microbial co-occurrence network with increased negative edge percentage and different network sizes. Climatic factors affected the taxonomic diversity directly and indirectly from altering the microbial interactions. The strengthen of negative interactions in communities directly induced the loss of soil organic carbon. [Conclusion] The increasing hydrothermal conditions will significantly change the microbial community co-occurrence network of mollisol soils, and the response of network hub microbes will be more sensitive.

Key words:increasing hydrothermal conditions;soil transplantation experiment;microbial co-occurrence network;hub microbes