Bacterial community structure and assembly dynamics hinge on plant litter quality

Area of Science:

• Ecology
• Microbial Ecology
• Biogeochemistry

Background:

• Litter decomposition is a crucial ecosystem process for nutrient and energy cycling.
• Understanding microbial community dynamics is key to predicting ecosystem functions.

Purpose of the Study:

• To investigate how litter quality affects bacterial community assembly and decomposition rates.
• To differentiate between stochastic and deterministic processes in microbial community development.

Main Methods:

• A 360-day laboratory incubation experiment.
• Comparison of low C/N deciduous litter (DL) and high C/N coniferous litter (CL).
• Analysis of bacterial community composition, diversity, and litter mass loss.

Main Results:

• Faster litter mass loss and higher taxonomic diversity in deciduous litter (DL) incubations.
• Stochastic bacterial community assembly observed with DL throughout the experiment.
• Rapid alpha-diversity decline and a shift from stochastic to deterministic assembly with coniferous litter (CL) after 180 days.

Conclusions:

• Litter quality significantly influences bacterial community assembly and decomposition rates.
• Environmental selection and competitive interactions shape microbial communities, especially with recalcitrant litter.
• Microbial diversity and assembly are critical for ecosystem processes like soil carbon sequestration under changing climates.