ADVANCES AND POTENTIALAPPLICATIONS OF BIOCHAR-BASED ORGANOMINERAL FERTILIZERS TO IMPROVE NITROGEN USE EFFICIENCY
Nitrogen (N) is an essential nutrient for plant growth, but its use efficiency (UNE) is often limited by losses due to leaching, NH volatilization, and denitrification, impacting both productivity and the environment. Factors such as fertilizer type, soil characteristics, climate, and crop directly influence UUE, with sandy tropical soils being particularly susceptible to N losses. Biochar derived from organic waste has proven effective in mitigating these losses, acting as a soil conditioner, increasing pH, moisture retention, porosity, and microbial activity, favoring greater N absorption by plants. This review summarizes recent evidence on the role of biochar in improving ENU, reducing N losses, and enabling innovative fertilizer formulations. Studies indicate that biochar modified or used as a coating for urea, as well as organomineral fertilizers, promotes the gradual release of N, increases macroaggregate stability, reduces leaching and gaseous emissions, and increases productivity. In addition, innovative formulations incorporating lauric acid or Hermetia illucens by-products increase the multifunctionality of biofertilizers and contribute to circular economy practices. These strategies link nutrient management to waste valorization, contributing to more sustainable fertilization approaches.