Sustainable Applications of Biochar for Environmental Control and Promotion of the Circular Economy

Biochar has gained global recognition in agriculture for its multifaceted benefits in promoting agro-ecosystem sustainability. It effectively sequesters carbon in the soil, contributing to the mitigation of CO2 emissions, while concurrently enhancing soil fertility, nutrient use efficiency, and crop productivity. In developing countries, traditional methods like pit kilns, ground pit kilns, and clay pot kilns prevail as the primary means of biochar production among smallholder farmers due to limited investment capacities. Consequently, traditional charcoal production serves as the main source of biochar for these farmers in rural areas. Various studies have demonstrated the positive impact of biochar derived from wooden feedstocks on crop yields, such as doubling corn yield in degraded soils and promoting increased yields in infertile and acidic soil for multiple years. The choice of feedstock and pyrolysis temperature significantly influences the nutritional content, nutrient release rate, and agronomic efficiency of biochar. Different feedstocks, pyrolysis temperatures, and application rates have distinct effects on crop performance, including nutrient uptake, yield improvement, and soil properties. Moreover, biochar plays a pivotal role in the circular economy by facilitating organic matter and nutrient recovery. Its utilization spans diverse sectors, including agriculture and municipalities. Several case studies from Kenya, Botswana, Bangladesh, and Ghana showcase the successful application of biochar in different contexts, highlighting its potential for sustainable and environmentally friendly practices.