Wetland types shape microbial function related to soil phosphorus cycling based on metagenomics analysis

Area of Science:

• Environmental Science
• Microbiology
• Soil Science

Background:

• Phosphorus (P) limitations are common in ecosystems.
• Understanding wetland impacts on soil P availability and cycling is key for effective wetland management.

Purpose of the Study:

• To investigate how different wetland types influence microbially mediated soil P fractions and cycling.
• To identify key environmental drivers shaping these microbial processes.

Main Methods:

• Selected coastal, constructed, and swampy wetlands in Tianjin, China.
• Employed sequential P extraction and metagenomics to analyze soil P fractions and microbial genes.
• Assessed environmental factors like salinity, nutrient concentrations, and C:N ratios.

Main Results:

• Proteobacteria dominated microbial P cycling genes.
• Organic P (Po) mineralization was linked to IMPA, gph, rsbU_P, ugpQ, and glpK genes.
• Inorganic P (Pi) solubilization was associated with gcd, ppa, and ppx genes.
• Salinity, NO3--N, TC/TN, TC, and SOC/TP ratios were key drivers.
• High salinity and nutrient imbalance promoted Po mineralization; low salinity favored Pi dissolution.
• Coastal wetlands showed the lowest microbial network complexity related to P cycling.

Conclusions:

• Soil P cycling is significantly influenced by wetland type and environmental conditions.
• Salinity and nutrient status jointly regulate microbial P mineralization and solubilization.
• Findings provide insights for managing P cycling in diverse wetland ecosystems.