Response of Conservation Agriculture on System Productivity and Carbon Sequestration in Rice-Based Cropping Systems

Low crop yields due to constant monocropping systems and deteriorating soil health in a smallholder farmers’ field of Indo-Gangetic plains of India have led to a quest for sustainable production practices with greater resource use efficiencies. The aim of the study was to elucidate the short term effects of conservation agricultural systems on productivity, soil health and carbon sequestration rate of soils in three different diversified cropping systems. The treatments consisted of two different tillage systems (conventional and reduced tillage), two mulch levels (no and straw mulch) and two levels of fertility (100 and 75% RDF) were compared in three rice-based cropping systems (rice-wheat; rice-vegetable pea-greengram; and rice-potato-maize sequences) for two years on an experimental field (clay loam) located at Norman E Borlaug Crop Research Center, Pantnagar, India. The resource conservation technologies (RCT) i.e. reduced tillage, mulch, and 100% RDF had recorded 2.5 and 3.0% higher system productivity and relative production efficiency in rice-vegetablepea-greengram and rice-potato-maize sequences, respectively in two consecutive years. Conservation tillage had sequestered three times higher carbon than conventional tillage while mulching acted four times higher than non-mulched condition in agricultural soils. Even though cropping system not significant significantly influenced on carbon sequestration, rice-vegetablepea-greengram sequence had recorded higher carbon sequestration rate and higher soil organic carbon stock noted in surface plough sole layer than any other cropping systems. Therefore, our results suggested that Indo-Gangetic farmers should consider adopting resource conservation practices together in indogangetic area because of benefits to soil health, carbon sequestration and system productivity.