Aggregate associated phosphorus and zinc affected by long term crop residue incorporation and initial zinc application in calcareous soil

Calcareous soil usually suffer from lack of nutrient especially zinc and phosphorus. We studied the influence of different levels crop residues incorporation on aggregate associated phosphorus and zinc in soil aggregates after 23 years of continuous rice- wheat cropping system on sandy loam calcareous soil. The result shows that concentration of available phosphorus and zinc within water-stable aggregate showed an inverse relationship with aggregate size. It might be due to increase in surface area with decrease in particle size.