Use of biochar as a sustainable agronomic tool, its limitations and impact on environment: a review

Abstract Ensuring global food security under present and futuristic scenario of climate change accompanied by expanding population is of major concern worldwide. Researchers across the world are focusing on sustainable agronomic practices to combat climate change induced issues like desertification, reduction in crop yield, pest outbreaks, and reduction in soil health. Biochar has demonstrated positive effects on plant growth, development, fruit quality, carbon capture and sequestration. Studies indicate that biochar amendments to soil can enhance soil health, plant growth and development as well as help in combating abiotic stressors. Biochar has several properties that make it an attractive soil amendment, including high porosity, surface area, water-holding capacity, and the ability to increase soil microbiota, which in turn can promote nutrient uptake and reduce soil erosion. Environmentally, biochar’s ability to degrade organic pollutant as well as sequester carbon makes it a very attractive addition to sustainable agriculture. Nonetheless, biochar has also been reported to have potential hazardous impacts on human health associated with possible leakage of toxic elements and particulate matter pollution. However, lack of exhaustive studies that detail all the major aspects of biochar application in agroecosystem impedes decision making on its overall usability in agriculture. There exists a need for comprehensive review that cover all the important aspects of biochar supplementation. This review provides a thorough overview of the multifaceted impacts of biochar, encompassing its positive effects on soil, plant growth, development and environment, while also exploring the limitations along with potential toxic effects associated with its application.