Circular economy of composting in Sri Lanka: Opportunities and challenges for reducing waste related pollution and improving soil health

Inadequate management of organic waste is a key cause of environmental pollution and nutrient loss in developing countries. Composting is a win-win option that allows for not only reducing environmental pollution derived by open dumping of waste but also recovering nutrients essential for crop production, consequently enhancing crop yields and reducing expensive chemical fertilizers usage. Considering these environmental and economic benefits, this study develops an economic optimization model to assess the impact and financial feasibility of compost production and marketing in Sri Lanka. The analysis does not treat compost production as an isolated sector, but traces the combined relationship between compost and chemical fertilizer applications for sustainable crop production. The findings indicate that establishing compost facilities to recycle organic waste in Sri Lanka will decrease total waste management and chemical fertilizer use costs by US$191 million. Facilitating inter-provincial trade in compost will further expand the composting potential in the country, reducing waste management and chemical fertilizer use costs by US$357 million. Successful implementation of wide-scale composting projects will require better accounting and planning in the waste management system, greater public awareness about waste derived environmental pollution, and better working conditions and safety in the sector. Increased use of compost in crop production in Sri Lanka depends on improved mechanisms for monitoring and certifying compost quality, more effective compost subsidy policies and increased knowledge and application of Integrated Nutrition Management measures. (C) 2018 Elsevier Ltd. All rights reserved.