Effect of crop residue management on carbon sequestration in soil – An Overview

The Paris Agreement calls for limiting global warming below 2°C. The “4 per 1,000 Initiative: Soils for food security and climate” was launched in 2015 to increase soil organic carbon sequestration with three objectives: mitigation of climate change, adaptation to climate change and improved food security (Demenois et al., 2020). Agricultural carbon (C) sequestration may be one of the most cost-effective ways to slow processes of global warming. Carbon sequestration is the long-term storage of carbon dioxide or other forms of carbon in oceans, soils, vegetation (especially forests), and geologic formations to either mitigate or defer global warming. It is a way to reduce the accumulation of greenhouse gases, which are released due to human activities (Nair et al., 2015). One among the ways to achieve soil carbon sequestration is retention of crop residues on the soil. Crop-residues are the plant parts that are left in the field after harvesting of a crop. Large quantities of residues are generated every year in agriculture. They are the potential natural resources that alter the soil environment, which in turn influences the soil microbial activity and subsequent nutrient transformations. Crop residue management (CRM) is a widely used cropland conservation practice. Crop residue provides significant changes in soil physical, chemical, and biological functions. Crop residues act as substrate for soil microbes which promote their growth and activities in rhizosphere. With the retention of crop residues allows detention and raise in organic matter levels and acts as substratum for soil microbial activity and potential capacity of soil to hold the carbon and to supply nutrients and water “on demand” to roots for prolonged period of time (Kassam et al., 2009). They also affect water movement, infiltration, runoff, and water quality. Crop residues on soil surfaces are known to reduce both wind and water erosion either directly by affecting the physical force involved in erosion or indirectly by modifying the soil structure through the addition of soil organic matter (SOM). Residues, aid in maintaining soil fertility by improving soil microbial biomass, soil organic carbon, carbon management index and nitrogen economy.