Charring the Waste Biomass To Precious Biochar: A Resource for Sustainable Agriculture

Abstract

Biochar has emerged as a sustainable tool in advancing the agricultural productivity. Biochar production and its application have drawn attention because of its unique properties, including carbon content, high specific surface area, stable structure, and cation exchange capacity. The papers selected for this review present the latest and appropriate information. Special attention was given to various modification techniques, biochar’s role in soil health, effects on crop productivity and pollutant remediation. Many sources such as Scopus, Elsevier, Springer and other online databases were used for searching the publications. Several previous studies have shown that biochar addition in the soils increased the mean crop productivity up to 10%. Despite the overall gain being slight, it was statistically significant. However, as part of the whole study, outcomes from every analysis ranged from − 28% to 39%. Additionally, biochar application enhances crop yield by 10–14% by altering soil texture and pH. Thus, improved water-holding capacity, crop nutrient availability, and the liming effect of biochar were the key factors for crop productivity. It also reduces the mobility and toxicity of various pollutants from soil and minimizing ecological risk. Moreover, biochar production can aid in the reduction of greenhouse gas emissions (6–90%). Although extend of mitigation largely depends on application rate and other environmental factors. Biochar surface qualities can be modified using physical or chemical techniques to make it better for the intended use. Oxidising agents, metal ions, acid, alkali, steam, and gas purging can be used to alter biochar and accordingly, biochar can be used to address various environmental issues. The preparation, modification, and environmental use of biochar are thoroughly examined and reported in this review. This review will contribute to our understanding of the viability, security, and efficiency of biochar use for sustaining soil fertility and enhancing plants’ resilience to various stresses. © The Author(s) under exclusive licence to Sociedad Chilena de la Ciencia del Suelo 2025.