Assessing the potential sustainability benefit of Agricultural residues: Biomass conversion to Biochar and its use for soil and crop improvement

AGRICULTURAL residues represent a significant challenge to proper management. Biochar provides a sustainable way for the management of agricultural residue and other waste biomass. Biochar is a form of carbonized biomass which have received attention due to its wide application. Pyrolysis, torrefaction, gasification, hydrothermal carbonization, and standard carbonization techniques are used for biochar preparation. Properties of biochar depends on the techniques and environment used to produce it. In order to optimise the performance of biochar for particular purposes, physical, chemical and biological modification has been opted by different researchers. Direct application of biochar in the agricultural soil reported to improve the soil pH, water holding capacity, fertility, crop growth and yield. Biochar also act as slow release fertilizers (SRFs), which have a huge potential to increase the soil fertility along with agronomic performance and decrease the amount of greenhouse gases released into the environment from the soil. Overall, use of biochar as sustainable high-value products seems to have a very promising future. This review provides a comprehensive review of the material and methods for biochar preparation, modification techniques, properties of biochar and its performance in agriculture soil.