Soil Aggregation and Aggregate-associated Carbon affected by Long-term Crop Residues Incorporation in Rice-Wheat Cropping System

Abstract

Crop residue management is one of the options for enhancing soil organic carbon stabilization by improving soil aggregation in semi-tropical soil. We studied the influence of different levels crop residues incorporation on aggregation and carbon stabilization in different soil aggregates after 23 years of continuous rice- wheat cropping system on sandy loam calcareous soil. 100% residue incorporation caused a significant increment of 49.09 % in total water stable aggregates (>0.25 mm) in surface soil. Carbon content in both macro- and microaggregates was increased, but increment was greater in macroaggregates (33.47%) than microaggregates (16.23%). These results show that long-term application of organics in combination with inorganic fertilizers helped in carbon accumulation in macroaggregates, and thereby improving soil carbon status.