Abstract
This literature review explores the importance of organic fertilizers as a strategy for sustainable management of organic waste and promotion of organic agriculture. In particular, it aims to establish the link between the production and conversion of organic by-products into bioresources and their integration into organic agriculture. It reviews the various technical processes of converting organic waste into fertilizer. Among the processes examined, composting remains the most widely used because of its technical simplicity and economic profitability. Other processes examined that may be used to recover the mineral elements contained in organic by-products include anaerobic digestion, vermicomposting, solid and liquid fermentation, biochar production. Thus, the various studies examined on the application of these fertilizers reveal that they contribute to a significant improvement in soil fertility while increasing microbial biomass and enzymatic activity, particularly those of urease, phosphatase and dehydrogenase. In addition, these fertilizers are responsible for the increase of the yield rate that can exceed 50% in comparison with untreated soil and the nutritive value of crops. Despite multiple advantages, the valorization of organic waste for agricultural purposes still requires rigorous management, standardization and reasoned integration.