Biochar: the Earth’s black gold – a sustainable agricultural revolution

Abstract Biochar, a carbonaceous by‐product of pyrolytic biomass, is currently attracting worldwide attention with its immense scope to transform sustainable agriculture. This review elaborates on the effect of biochar on soil physicochemical and biological characteristics, crop yields, and tolerance to environmental stresses. Biochar enhances soil porosity, water holding capacity, nutrient supply, and microbial activity and thus enhances plant growth and yields. Its performance is very much a function of feedstock quality, pyrolysis parameters, and application rates, with low‐temperature biochar favoring nutrient supplementation and high‐temperature biochar favoring carbon sequestration over the long term. Biochar also decreases the bioavailability of heavy metals and alleviates plant stress owing to drought, salinity, and pathogen attack. The variability in outcomes for different soils and potential for contaminants require standards‐based production and site‐specific application protocols. This review identifies biochar’s diverse advantages and creates a blueprint for its safe and efficient application as a long‐term amendment in multiple agricultural systems.