Agroforestry's ecological promise: A global meta-analysis reveals context dependence, temporal decline, and policy implications

Balancing the demand for agricultural production with the maintenance of ecosystem services, climate mitigation and adaptation, and biodiversity conservation will be a major challenge of this century. Crop production in agroforestry systems is being widely practiced with the expectation that it can simultaneously meet all of these goals. This study conducts a global meta-analysis of peer-reviewed literature on agroforestry outcomes. By synthesizing 1328 matched data pairs from 42 studies across 14 countries, using indicators that encompass biodiversity, soil properties, and carbon-related metrics, we find that agroforestry has a positive impact, improving overall environmental performance by 13.0%. After accounting for the influence of the replaced land-use type, agroforestry shows a 44.5% improvement in environmental performance relative to monoculture plantations. However, in contrast to reference native forests, its effect on environmental performance is not significant (RR = −0.02, 95%CIs = −0.12 to 0.09). Furthermore, the likelihood of agroforestry systems delivering simultaneous benefits across the assessed ecological indicators declined with increasing implementation duration. These findings demonstrate that the ecological value of agroforestry is fundamentally context-dependent, underscoring the necessity of incorporating baseline land-use history into policy design and environmental assessment frameworks for sustainable land management.