Enhancing Carbon Sequestration Potential, Productivity and Sustainability of Mustard Under Conservation Agriculture in Semi-arid Regions of India

Abstract

Maintaining and building up of soil organic carbon (SOC) is very critical for sustaining soil health and crop productivity. Declining SOC is a major concern in semi-arid regions and can be addressed by alteration in the establishment method, involving reduced tillage, bed planting and residue management. For standardizing these crop establishment methods, a field experiment was conducted at Directorate of Rapeseed-Mustard Research, Bharatpur, India from 2009–10 to 2012–13. The effect of conventional tillage (CT), reduced tillage, zero tillage (ZT), and permanent furrow irrigated raised beds (FIRB) on carbon sequestration potential (CSP), sustainability and productivity of Indian mustard under five mustard-based cropping systems, viz, fallow-mustard, green manure-mustard, brown manure-mustard, cluster bean-mustard, and pearl millet-mustard was studied. The experiment was conducted in split-plot design with three replications. The variable tillage practices under different cropping systems significantly affected the soil physical properties and organic carbon dynamics, besides improving mustard productivity and sustainability. An increase of 50 and 16.1 %, respectively was recorded in SOC and infiltration rate under ZT over CT. Likewise, 1.4 and 8.4 folds increase was recorded in mass of soil organic carbon and CSP, respectively in ZT over CT. The bulk density was reduced by 37.3 % in ZT over CT. The highest seed yield was obtained under FIRB (2765 kg ha−1, 23.6 % higher over CT), followed by ZT (2533 kg ha−1, 17.5 % higher over CT). The highest growth, yield, sustainability indices and improved bulk density, infiltration rate, SOC and CSP were recorded under green manure-mustard system followed by brown manure-mustard system.