CONCLUSION
Overall, our results demonstrate that high AMF diversity enhanced
ecosystem multifunctionality. However, under multiple GCFs, the
competition among AMF likely intensified, leading to no significant
differences in ecosystem multifunctionality between high and low fungal
diversity treatments. These multiple GCFs also may have enabled plants
to select more efficient mycorrhizal partners, ensuring that high AMF
diversity consistently benefited plant photosynthesis and growth. Our
findings suggest that BEF studies should integrate both aboveground and
belowground multi-trophic levels biodiversity within a unified
framework. Additionally, our research emphasizes the importance of
preserving AMF diversity for plant growth, particularly in agricultural
ecosystems that are suffering from multiple global changes.