Functional Diversity and Tropical Forest Ecosystem Dynamics and Productivity: A Review

Abstract

Tropical forests are being reshaped by land-use change, climate stress, altered disturbance regimes, and biotic change. However, the ecological consequences of biodiversity loss cannot be fully understood from species richness alone. This narrative review examines how functional diversity—the range, distribution, and relative abundance of organismal traits—influences forest productivity, carbon storage, resource use, stability, resilience, and ecosystem multifunctionality. The review synthesizes a carefully selected body of literature published between 2016 and 2026, excluding duplicate records, retracted publications, studies published before 2016, and research that did not directly address biodiversity–ecosystem functioning relationships in forests. The evidence shows that functional diversity generally enhances biomass production and carbon storage by promoting resource-use complementarity. However, these effects are rarely independent of other factors, including functional identity, stand structure, phylogenetic diversity, soil conditions, climate, and disturbance history. Positive diversity–productivity relationships are most evident where trait differences improve access to limiting resources, although the influence of dominant species and tree-size variation can exceed that of trait diversity in some forest systems. The relationship between functional diversity and resilience is more conditional. Hydraulic and response diversity can improve resistance and recovery following disturbance, yet recent syntheses does not support a universally positive effect of functional diversity on ecosystem recovery. Likewise, mixed-species stands do not necessarily maximize ecosystem multifunctionality because different ecosystem functions respond to distinct biotic and abiotic drivers. The review therefore calls for a multiscale framework that is context dependent and integrates functional effect traits, response traits, vertical structure, belowground interactions, and environmental constraints. This approach could improve tropical forest conservation, restoration and monitoring by shifting management from maximizing species numbers to maintaining complementary strategies, key functional identities, response diversity and spatial heterogeneity.