Research Article // Integrating the Nexus approach in sludge management: co-composting wastewater sludge and green waste for enhanced forestry
By Khacheba et al. This study shows that integrating the WEF-Nexus approach into sludge management through the co-composting of wastewater sludge and green waste offers a scalable, low-carbon solution that enhances soil restoration, supports afforestation, and advances circular economy objectives in arid regions such as Algeria.
Abstract
Algeria faces pressing challenges in managing approximately 50,000 tons of wastewatersludge per year—classified as special wasteunder the 2006 decree—and around 3 million tons of green waste, most of which are disposed of unsustainably. This paper proposes the co-composting of these waste streams through a Nexus Approach that interlinks water, energy, and food systems. The method balances the nitrogen-rich sludge with carbon-rich green waste to produce high-quality compost for soil restoration. Pilot projects within Algeria’s Green Dam reforestation program have demonstrated 15–20% higher seedling survival rates, improved soil health, and reduced emissions—avoiding an estimated 500,000 tons of CO2 annually from open burning. Although policy gaps remain, Law No. 25–02 (2025) provides a framework for integrating circular economy principles. The economic benefits include cost savings, job creation, and decreased dependence on imported fertilizers. Case studies, such as those conducted in Djelfa, highlight the role of compost in arid-land afforestation. Scaling up co-composting could sequester up to 150,000 tons of CO₂ per year, aligning with the Sustainable Development Goals (SDGs) and national climate objectives. This approach transforms waste into a valuable resource, offering a replicable model for sustainable development in arid regions.
Published
22 December 2025
In
By
International Journal of Environmental Science and Technology