Biochar mediated fixation of nitrogen compounds (ammonia and nitrite) in soil: a review.

Biochar (BC) is a carbon-rich material created from biomass pyrolysis. It is an efficient addition for reducing ammonia inhibition due to its large specific surface area, porosity, conductivity, redox characteristics, and functional groups making it favorable for both soil and water remediation. The efficacy of biochar on the N cycle is associated with biochar properties which are mainly affected by feedstock type and pyrolysis condition. The addition of BC to soil affects nitrogen adsorption pathways. Other advantages include improved soil fertility, nutrient immobilization, and slow-release carbon storage. Biochar adsorption of ammonia reduces ammonia (NH) and nitrate (NO) losses during composting after manure applications and provides a method for creating slow-release fertilizers. Depending on the N source and the properties of the biochar, NH loss reductions vary. Besides improving soil dynamics, BC can also be used in wastewater treatment. Engineered or designer biochar is positioned as a promising material for wastewater treatment due to its enhanced properties and versatility.