Effect of Conservation Tillage on Changes in Soil Aggregate-associated Organic Carbon and Biological Pools to Nitrogen and Straw Alters in RWCS in North-Western India: A Review

Abstract

To manage this issue, understanding the mineralization process of crop leftovers is helpful. C and N mineralization kinetics in surface-applied and soil-integrated rice and wheat residues were investigated. Rice and wheat residues bind nitrogen in the soil. The use of the residue increased soil organic carbon by 18% and aggregate stability by 55% compared to the control. This study concludes that instead of simply leaving agricultural wastes on the surface, it is best to work them into the soil, where they will decompose more quickly, the mineral N will be released more quickly, more organic matter will be produced, and the soil structure will be improved. Compost amendment was more effective in decreasing macro-aggregate and silt+clay fraction-specific activities than fertilizer NPK. Tillage and residue levels had a significant impact on soil organic carbon accumulation between 0 and 15 centimeters, but not between 15 and 30 centimeters. The SOC content of plots that used raised beds permanently and retained residue was 19.44 g kg-1, but the SOC content of plots that used zero-tilling was only 18.53 g kg-1. SOC levels in puddled rice grafts and conventionally tilled wheat were both 15.86 g kg-1. When compared to plots where the residue was removed, those where it was left but not tilled sequestered 0.91 g kg-1yr-1 SOC. After receiving NT treatments, the concentration of DOC in three different soil depths (bulk, >0.25 mm aggregate, and 0-5 cm soil) increased by 15.5%, 29.5%, and 14.1%, respectively. Increases in MBC ranged from 11.2% to 11.5% to 20%. The 0-50 cm depth SOC stock increased from 49.89 Mg ha-1 to 53.03 Mg ha-1 when the residue was removed. SOC stock was grown by 50 centimeters by rotational farming, but by just 5.35 percent through no-till farming. Bulk soil SOC was 12.9% higher in S treatments compared to NS treatments that removed crop residue, as were >0.25 mm aggregate (11.3%) and 0.25 mm aggregate (14.1%). While NT treatments increased DOC by 15.5%, 29.5%, and 14.1% in bulk soil, >0.25 mm aggregate, and 0.25 mm aggregate in the 0-5 cm soil layer, respectively, CT treatments increased MBC by 11.2%, 11.2%, and 20%. The 0-5 cm soil layer, bulk soil, and >0.25 mm aggregate all saw increases in DOC content of 23.2%, 25.0%, and 37.5% after receiving S treatments compared to NS treatments, while MBC increased by 29.8%, 30.2%, and 24.1%.