Sustainable Management of Leucaena leucocephala in Wetland and Riparian Ecosystems: A Systematic Review of Ecological Impacts and Control Strategies

Leucaena leucocephala is a nitrogen-fixing legume widely used in agroforestry systems, although its invasive potential poses increasing risks to wetlands and riparian ecosystems. This systematic review synthesizes current knowledge on the ecological mechanisms, environmental stressors, and management strategies associated with the invasion of L. leucocephala in humid tropical environments. Following PRISMA guidelines, 60 studies retrieved from Scopus, Web of Science, and Consensus were qualitatively analyzed. The results indicate that invasion success is strongly associated with environmental disturbances and stress conditions, particularly drought stress, altered hydrological regimes, fire occurrence, and land-use change, which reduce ecosystem resistance and facilitate species establishment. Key invasion mechanisms include high seed production, persistent soil seed banks, rapid growth, allelopathic effects, and strong resprouting capacity, leading to suppression of native vegetation and structural simplification of plant communities. Integrated management strategies combining mechanical and chemical control with active revegetation consistently showed higher effectiveness than isolated approaches. The evidence further suggests that climate-related stressors may intensify invasion dynamics and increase ecosystem vulnerability under future climate scenarios. Despite recent advances, important knowledge gaps remain regarding long-term ecosystem functioning, hydrological feedback, and adaptive management in invaded wetlands.