Abstract
Fine root traits critically regulate resource acquisition and ecosystem nutrient cycling. Despite their importance as integrated indicators of plant responses to environmental shifts, community-level adaptations of fine root traits to global climate and soil nutrient gradients remain poorly understood. This study synthesizes data from 301 natural communities worldwide to examine the mechanisms driving fine root trait variation across different community types. Our findings demonstrate distinct regulatory pathways: precipitation negatively correlates with root tissue density, reflecting optimized resource capture in humid environments, whereas in arid regions, higher root tissue density enhances resilience by increasing structural stability and prolonging root lifespan to cope with resource scarcity. Additionally, temperature-driven phosphorus limitation reduces root phosphorus content. Soil nutrient enrichment promotes thinner roots and elevated specific root length, indicative of autonomous nutrient acquisition strategies, while nutrient scarcity favors thicker roots and reduced specific root length, signifying increased mycorrhizal dependence. The divergent patterns of root nitrogen content in relation to soil nitrogen between grasslands and forests suggest that grasslands employ an "acquisitive" nutrient acquisition strategy, while forests adopt a more "conservative" approach. Principal component analysis reveals coordinated variation in community-level root traits, challenging the universality of the species-level root economics space. This study emphasizes the integrated responses of community-level root traits, offering new insights into plant resource economics in the context of global environmental change.
Competing Interest Statement
The authors have declared no competing interest.
