Soil alkaline phosphatase-encoding bacteria relate closely to microbial biomass phosphorus in changing environments

Area of Science:

• Soil Microbiology
• Biogeochemistry
• Environmental Science

Background:

• Microbial biomass phosphorus (Pmb) is a crucial soil phosphorus pool, influencing plant productivity.
• Alkaline phosphatase-encoding bacteria (PEB), identified by the phoD gene, are key players in organic phosphorus mineralization.
• The relationship between soil PEB and Pmb, especially under environmental change, is not well understood.

Purpose of the Study:

• To investigate the linkage between soil microbial biomass phosphorus (Pmb) and alkaline phosphatase-encoding bacteria (PEB) communities.
• To understand how environmental changes affect Pmb and the abundance and diversity of PEB.
• To differentiate the ecological roles and community assembly of rare versus abundant PEB.

Main Methods:

• Utilized molecular and statistical tools in controlled environmental change simulation experiments (rainfall, pH, warming).
• Conducted a field investigation to assess Pmb and PEB in a real-world setting.
• Analyzed the correlation between Pmb content, phoD gene abundance, and specific bacterial genera (e.g., Stenotrophomonas).

Main Results:

• Bacterial Pmb, not fungal, significantly responded to environmental changes, with higher Pmb and phoD abundance under less disturbed conditions.
• Pmb content showed a significant positive correlation with phoD gene abundance across both experimental and field data.
• Rare PEB exhibited higher community diversity and environmental restriction, while abundant PEB showed stronger species replacement and phylogenetic signals.

Conclusions:

• The phoD gene in PEB is a significant contributor to soil Pmb dynamics.
• Environmental changes negatively impact Pmb and alter PEB community structure.
• Both rare and abundant PEB communities are governed by stochastic processes, with distinct responses to environmental shifts.