How do various strategies for returning residues change microbiota modulation: potential implications for soil health

Area of Science:

• Soil Microbiology
• Agricultural Science
• Environmental Science

Background:

• Residue incorporation is vital for agricultural land management.
• The impact of different residue returning strategies on soil microbiota and soil health is not well understood.
• Soil microbiota are essential for maintaining soil health.

Purpose of the Study:

• To investigate the effects of various residue management strategies on soil microbial communities.
• To analyze the impact on microbial functional genes, nutrient cycling, antibiotic resistance genes (ARGs), and pathogens.
• To identify potential indicators for functional changes in response to residue additions and provide recommendations for cropland management.

Main Methods:

• Implementation of different residue management strategies: chopped residues (SD), composted residues (SC), and pyrolyzed residues (BC).
• Conventional fertilization (CK) served as the control.
• Metagenomic sequencing was employed for analysis.

Main Results:

• All residue strategies minimally affected microbial diversity (α and β) but significantly altered functional genes involved in carbon (C), nitrogen (N), phosphorus (P), and sulfur (S) cycling.
• Chopped residues enhanced C, N, P, and S cycling genes; composted residues primarily stimulated C and S cycling.
• Residue treatments disrupted nutrient cycle relationships (SD < SC < BC), increased ARGs, and SC led to an increase in certain pathogens.

Conclusions:

• Residue management strategies profoundly influence soil microbial functions and nutrient cycling, with varying impacts on ARGs and pathogens.
• The study identified potential indicators for functional changes and offers insights for optimizing cropland management for soil health.
• Understanding these microbial shifts is crucial for sustainable agricultural practices.