The escalating problem of invasive aquatic weeds and harmful algal blooms presents a dual challenge: environmental degradation and the underutilization of biomass resources. Species such as Eichhornia crassipes (water hyacinth) and Lantana camara proliferate rapidly, disrupting aquatic ecosystems, while cyanobacterial and algal blooms deplete oxygen and release toxins into water bodies. Traditionally, such biomass has been discarded or incinerated, contributing little to the economy and further exacerbating environmental concerns. However, these neglected biological resources are rich in lignocellulose, polysaccharides, lipids, proteins, and bioactive compounds, making them potential feedstocks for a range of value-added applications.
This paper proposes an integrated weed–algae valorization system within a circular economy framework, aimed at converting environmental hazards into sustainable wealth. The approach emphasizes a multi-stream biorefinery model in which harvested weed and algal biomass undergoes sequential or parallel processing to generate diverse products: (i) biofuels and biogas via fermentation and anaerobic digestion, (ii) biochar through pyrolysis for soil enhancement and carbon sequestration, (iii) nutrient-rich biofertilizers from algal residues, (iv) natural pigments and phytochemicals for industrial and nutraceutical applications, and (v) activated carbon from residual biomass for water purification. In this integrated scheme, the waste of one process becomes the input for another, ensuring minimal residue and maximum resource efficiency.
The novelty of this system lies in coupling weed and algal valorization into a single, closed-loop framework tailored to the Indian ecological and socio-economic context. By simultaneously addressing invasive species management, renewable energy generation, sustainable agriculture, and environmental remediation, the model demonstrates the potential of transforming ecological nuisances into resources that align with the principles of the circular economy. Prospects include scaling such integrated systems into decentralized rural biorefineries, coupling with wastewater treatment plants, and embedding within policy-driven waste-to-wealth initiatives.
This work highlights how ―from waste to wealth‖ can move beyond rhetoric into tangible practice, showcasing innovation at the intersection of botany, biotechnology, and green chemistry for a sustainable future.