Deforestation impacts network co-occurrence patterns of microbial communities in Amazon soils

Area of Science:

• Microbiology
• Ecology
• Soil Science

Background:

• Co-occurrence networks reveal species associations crucial for community assembly and ecosystem functions.
• Understanding microbial community dynamics in tropical soils is vital, especially under land use change.

Purpose of the Study:

• To investigate prokaryotic co-occurrence patterns in Amazon soils.
• To assess how land use change to pasture affects these microbial networks.
• To hypothesize that altered microbial composition mirrors co-occurrence pattern changes.

Main Methods:

• Calculated Spearman correlations between operational taxonomic units (OTUs) from 16S rRNA gene sequencing.
• Constructed co-occurrence networks using robust correlations (≥0.80 or ≤-0.80, adjusted P < 0.01).
• Compared network features between forest and pasture soil ecosystems.

Main Results:

• Distinct forest and pasture prokaryotic networks showed altered compositional and topological features.
• Comparative analysis revealed changes in nitrogen cycling metabolic pathways.
• Soil physicochemical properties (temperature, C/N, H++Al3+) significantly impacted prokaryotic communities and network topology.

Conclusions:

• Changes in prokaryotic co-occurrence patterns and soil properties influence ecosystem processes.
• Nitrification and denitrification, key biogeochemical processes in tropical forests, are affected by these alterations.
• Microbial network analysis provides insights into ecosystem function under land use change.