Potential of Conservation Agricultural Practices on Soil Quality, Carbon Sequestration, Salinity Management and Productivity of Rainfed Areas

Intensive cropping, traditional tillage practices, and crop residue removal are the major factors of soil organic carbon (SOC) depletion. Restoration of SOC levels would improve the soil’s aggregate ability, physical, chemical, and biological properties, low greenhouse gas emission, and environmental sustainability. The importance of rainfed farming in India is increasing continuously with the increasing demand for feed, fodder, and fiber. It is technologically estimated that at any point in time, 50% of cropped area in India will remain under the rainfed system. The major challenges in rainfed areas include water scarcity, climate variability, and the lack of suitable technologies and practices resulting in half of SOC being present in arid soils than in moist environments. That's why the carbon sequestration in these soils requires a wide range of management practices to restore SOC levels. Conservation agriculture (CA) practices such as minimum tillage (MT), reduced tillage (RT), and zero tillage (ZT) may help in carbon sequestration and restoring SOC levels. The results of different studies revealed that ZT, MT and RT recorded higher total organic carbon, microbial biomass carbon, and particulate organic carbon as compared with conventional tillage and these are now established methods for promoting carbon sequestration and reducing greenhouse gas emissions in soils. The continuous tillage practices are a major threat to soil health, productivity, and fertility in dry areas. The tillage technology showed direct and indirect benefits in resource-saving ability and carbon sequestration. Long-term conservation tillage, judicious nutrient, and residue management practices increase the SOC content and enhance soil aggregation, hydraulic conductivity, soil porosity, and moisture retention capacity. Generally, the soil quality index (SQI) is used as a quantitative parameter to measure the effect of crop management practices on soil health. In tropical areas, the changes in different tillage practices, input, and residue management technologies offer a conclusive statement regarding the feasibility and sustainability of CA cropping systems. The SQI indicators are highly location and purpose-specific, as directly correlated with an ecosystem, physical, chemical, and biological processes, crop management variations, and properties of soil. This review aims to highlight the impact of conservation tillage practices that have potential possibilities for carbon sequestration in soils including salt-affected soils of rainfed areas.