Probing the impact of biochar combined with organic and inorganic amendments on soil carbon pools of rice (Oryza sativa) - wheat (Triticum aestivum) cropping system

Abstract

Biochar incorporation as a soil amendment has been shown to improve soil quality by sequestering carbon in soil for longer period of time. The two years field experiment was done at Agronomy research fields of Lovely Professional University, Phagwara, Punjab, India during 2018-19 and 2019-20 to probe the impact of biochar combined with organic and inorganic amendments on soil carbon pools of rice-wheat cropping system. The experiment was comprised with nine treatments viz., 100% Recommended Dose of Fertilizer (RDF), 50% RDF + Biochar, 50% RDF +25% FYM + Biochar, 50% RDF + 50% FYM + Biochar, 50% RDF +25% VC + Biochar, 50% RDF + 50% VC + Biochar, 50% RDF + 25% PM + Biochar, 50% RDF + 50% PM + Biochar, control (no fertilizer) and imposed in RBD design with three replications for each treatment. Pusa basmati 1121 and PBW550 varieties of rice and wheat was taken as a test crops. The results revealed that application of 50 % RDF + 50% PM + Biochar in rice and 50% RDF + 50% FYM + Biochar in wheat crop to soil significantly improved the soil carbon fractions i.e., Permanganate oxidizable carbon, Particulate organic carbon and Microbial biomass carbon at harvest of the crops during both years. This study has demonstrated that C pools in the soil can be enhanced by the biochar through stimulating soil microorganisms. Carbon storage in the soil is improved after biochar addition. By adding biochar with fertilizer and manures C sequestration can be enhanced. Based on the findings in this study, conventional fertilizer and manure application to soils could be associated with biochar through which multi-benefits (e.g., soil amendment, environment protection, and C sequestration) could be obtained simultaneously. Thus, converting rice straw to biochar for its application as soil amendment and C sequester decrease straw burning in open field in Northern India.