Soil microbial community assembly drives ecosystem multifunctionality under grazing disturbance by regulating...

Area of Science:

• Ecology
• Microbiology
• Environmental Science

Background:

• Global climate change and overgrazing significantly impact ecosystem multifunctionality (EMF).
• The specific roles of microbial community characteristics in mediating EMF under grazing pressure are not well understood.
• Understanding these microbial dynamics is crucial for ecosystem management and resilience.

Purpose of the Study:

• To investigate how microbial community diversity, network structure, and assembly processes influence ecosystem function and multifunctionality under varying grazing pressures.
• To determine the differential effects of light grazing, heavy grazing, and grazing exclusion on microbial communities and EMF.
• To elucidate the mechanisms by which microbial community assembly processes regulate EMF.

Main Methods:

• Comparative analysis of microbial communities (bacterial and fungal) across three grazing treatments (light, heavy, exclusion).
• Assessment of microbial diversity, richness, co-occurrence network structure (complexity, stability), and assembly processes (stochastic vs. deterministic).
• Quantification of ecosystem functions and multifunctionality (EMF) under each grazing condition.

Main Results:

• Light grazing significantly enhanced microbial diversity, richness, network complexity, and stability compared to heavy grazing.
• Soil microbial communities were primarily shaped by stochastic processes, with a shift towards deterministic processes under increased grazing pressure.
• Contrary to expectations, light grazing significantly reduced EMF compared to heavy grazing, suggesting a complex regulatory role of microbial communities.

Conclusions:

• Microbial community assembly processes, diversity, and network structure are key regulators of EMF under grazing disturbance.
• While diversity plays a role, the complexity and stability of microbial networks appear to be stronger predictors of EMF changes.
• Effective protection and management of microbial communities are essential for bolstering ecosystem resilience and promoting sustainable development.