Biotransformation of Biodegradable Solid Wastes into Organic Fertilizers using Composting or/and Vermicomposting

This review discusses the differences between composting and vermicomposting of biodegradable solid waste. Solid waste management is a major challenge worldwide due to the rise in population and industrialization, leading to larger amount of solid wastes being generated. Biological process has been widely recognized in converting solid organic materials into environmental friendly and value added products. Both composting and vermicomposting are regarded as a suitable way to manage organic waste because it not only helps solve the problem of waste disposal but also produces useful bio-amendment agent (organic fertilizer). In general, vermicomposting is a more superior process as compared to composting. This is because vermicomposting has higher organic matter decomposition rate and nutrients contents of final product. Besides, vermicompost produced higher concentration of hormones and enzymes that could stimulate plant growth and discourage plant pathogens. However, recent studies indicated that a successful combination between composting and vermicomposting has been considered as a possible way to obtain a better quality organic fertilizer. The suggestion to combine both systems is based on the premise that composting enables sanitization and elimination of toxic compounds from the solid wastes, while the subsequent or preceded vermicomposting rapidly reduces particle size and increases nutrient availability to the plants.