Recovery in methanotrophic activity does not reflect on the methane-driven interaction network after peat mining

Area of Science:

• Microbial ecology
• Environmental microbiology
• Biogeochemical cycles

Background:

• Aerobic methanotrophs are key players in peatland methane and nitrogen cycles.
• Peat mining disrupts methanotrophs, but restoration may aid recovery of activity and community.
• Microbial interactions (methanotrophic interactome) can enhance methanotroph resilience, yet their response to disturbance is poorly understood.

Purpose of the Study:

• To investigate the recovery of the methane-driven microbial interaction network in a restored peatland.
• To compare the methanotrophic interactome structure between pristine and restored peatlands.
• To link methanotrophic activity and community composition to interaction network changes.

Main Methods:

• Stable isotope probing (SIP) using 13C-methane to identify active methanotrophs.
• Co-occurrence network analysis of 13C-enriched 16S rRNA gene sequences.
• Comparison of microbial community composition and interaction networks in pristine versus restored peatlands.

Main Results:

• Methanotrophic activity and abundance recovered in the restored peatland.
• 'Methylomonaceae' dominated active methanotrophs, but relative abundances of other groups differed.
• The restored peatland exhibited a less complex and modular methanotrophic interactome, indicating reduced network connectivity.

Conclusions:

• While microbial activity and abundance recover, the methane-driven interaction network structure is significantly altered post-restoration.
• The reduced complexity of the microbial interactome in restored peatlands may compromise future resilience to disturbances.
• Assessing microbial interaction networks alongside activity and composition is crucial for a comprehensive understanding of ecosystem resilience.