Predicting nitrogen mineralization potential and availability of biochar-based agro-municipal solid waste co-compost using alkaline hydrolysis

•Valorization of agro-municipal solid wastes into value-added nutrient-enriched organic amendments for ameliorating soil fertility constraint is an environmentally friendly and sustainable approach to managing these waste streams.•An alkaline hydrolysis method for predicting nitrogen (N) mineralization potential and availability was validated using the long-term laboratory incubation and plant N uptake in soils amended with biochar-manure-composts (BMCs) of varied C/N ratios.•Increasing biochar content of the BMCs decreased the potentially hydrolyzable (Nmax) and mineralizable (No) N, which were reflected in lower mineralization (km) and hydrolysis (kh) rate constants.•Estimated Nmax, No, and N uptake by maize were significantly correlated, suggesting that the alkaline hydrolysis method offers a time-effective approach for predicting N mineralization in BMC-amended soils.