Effect of Biochar Application on Soil Chemical Properties, Nutrient Dynamics and Plant Nutrient Uptake

Abstract

Soil degradation, nutrient depletion, and declining nutrient-use efficiency are major constraints to sustainable agricultural production, creating a need for environmentally compatible soil amendments. Biochar, a stable carbon-rich material produced through pyrolysis of biomass under limited oxygen conditions, has emerged as a promising strategy for improving soil fertility, nutrient retention, and long-term carbon storage. The present study evaluated the effects of biochar application on soil chemical properties, nutrient dynamics, and plant nutrient uptake, with particular emphasis on soil pH, electrical conductivity, organic carbon, nutrient availability, and the influence of different biochar feedstocks and production conditions. Biochars derived from agricultural residues, woody biomass, and animal manure were considered, together with the effects of pyrolysis temperature, residence time, and physicochemical characteristics. Biochar application generally increased soil pH and buffering capacity, particularly in acidic soils, owing to the presence of alkaline minerals and basic cations. It also influenced soil electrical conductivity through the release and retention of soluble mineral nutrients. A prominent response was the enrichment and stabilization of soil organic carbon due to the recalcitrant aromatic carbon structure of biochar. Furthermore, its porous structure, large surface area, and reactive functional groups enhanced cation exchange capacity and promoted the retention of ammonium, potassium, calcium, magnesium, and phosphorus within the root zone. These improvements created favorable conditions for nutrient availability, root development, microbial activity, and plant nutrient acquisition. The effectiveness of biochar depended considerably on feedstock type, pyrolysis conditions, soil characteristics, and application rate. Overall, biochar represents a multifunctional and sustainable soil amendment capable of improving soil fertility, nutrient-use efficiency, plant nutrition, and carbon sequestration while reducing nutrient losses from agricultural systems.