Effect of Long Term Manuring and Fertilization on Carbon Mineralization in Soils of Finger Millet – Maize Cropping System in Alfisols

Quantitative information on carbon (C) mineralization of soil under different long term nutrient management is essential for better assessment of easily hydrolyzable C and loss of C from soil.With an aim to evaluate the differences in C mineralization due to long term fertilization and manuring treatments, a laboratory incubation study was conducted with soils (0-15 cm depth), collected from 33 years old finger millet -maize cropping system which involved application of 100% N, 100% NP, 50% NPK, 100% NPK, 150% NPK, 100% NPK + FYM (farmyard manure), 100% NPK + lime, control and uncultivated fallow land.Long-term application of fertilizers and manures significantly (p < 0.05) influenced C mineralization in soil.Long term integrated application of chemical fertilizers and organic manure in soil resulted in higher cumulative carbon mineralization, basal soil respiration (BSR), microbial and mineralization quotients.A judicious FYM application strategy through integration of both organic and inorganic sources is essential for improving and maintaining soil organic C pool.