Abstract
Aim Although mycorrhizal traits have been widely studied at the species level, their distribution and ecological significance at the community level remain poorly understood. We investigated how community‐level arbuscular mycorrhizal (AM) traits vary among grassland ecosystems differing in climatic conditions and land‐use regime. Location Europe and North America. Taxa Herbaceous vascular plants. Methods We analysed 104 grassland community surveys from 68 locations, comprising 1208 plant species. Species‐level mycorrhizal information was compiled from the FungalRoot and MycoFlor databases. We quantified community AM colonization rate (CAMR), community AM flexibility (CAMF), and interspecific variation in AM colonization rates (VAMR) using community‐weighted approaches. Grassland communities were classified into warm natural, cold natural, subnatural and seminatural grasslands. Results Semi‐natural grasslands exhibited the highest community AM colonization rates and mycorrhizal flexibility, indicating strong reliance on AM symbiosis and high potential for plasticity in mycorrhizal associations. By contrast, cold natural grasslands showed comparatively low community‐level AM reliance but high interspecific variation in AM colonization rates, suggesting weaker environmental filtering of mycorrhizal strategies under cold climatic conditions. Warm natural grasslands showed intermediate patterns. The high mycorrhizal flexibility observed in seminatural grasslands likely reflects adaptation to long‐term environmental heterogeneity associated with grazing, mowing and other forms of anthropogenic disturbance. Main Conclusions Our findings demonstrate systematic variation in community‐level mycorrhizal traits across grassland ecosystems and highlight the joint importance of climatic conditions and land‐use history in shaping plant–fungal interactions. Community‐level mycorrhizal metrics provide a promising framework for understanding the ecological organization of plant communities and their responses to environmental change.