From nuisance to resource: a global review of water hyacinth (Pontederia crassipes (Mart.)) valorisation for sustainable development.

Water hyacinth (WH), one of the world's most invasive aquatic plants, is increasingly being recognised as a valuable biomass resource for energy, agriculture, environmental remediation, and industrial applications. However, existing studies have largely examined these utilisation pathways in isolation, limiting understanding of their combined potential within sustainable development frameworks. This review presents a novel, integrated global synthesis of WH valorisation by simultaneously evaluating technological advances, ecological implications, and socio-economic dimensions. It maps emerging research trends, identifies knowledge gaps, and demonstrates the transition from conventional control approaches towards circular bioeconomy-driven resource recovery strategies. Key valorisation pathways reviewed include bioenergy production (biogas, bio-oil, bioethanol, and hydrogen), organic soil amendments, extraction of high-value biochemicals (e.g., nanocellulose, sterols, and xylitol), and bio-composite manufacturing. Beyond summarising current applications, the review critically assesses the interconnected technical, environmental, economic, institutional, and regulatory barriers that constrain large-scale implementation. A key contribution is the development of an integrated biorefinery framework that links WH harvesting, wastewater treatment, biomass conversion, and value-added product generation, particularly for resource-constrained regions. The review further identifies priority research directions, including life-cycle assessment-based decision-making, process integration, and scalable deployment models. By repositioning WH as a strategic bioresource rather than an ecological burden, this review provides a comprehensive roadmap for transforming invasive biomass management into a driver of sustainable development and circular bioeconomy growth, particularly in low-income regions disproportionately affected by WH proliferation.