Effect of long-term tillage practices on soil nitrogen, phosphorus and sulfur release under different nitrogen management options

The conservation agriculture (CA), presents a promising alternative for restoring soil health and achieving sustainable crop production. In addition, one cannot follow the same nitrogen management of conventional framing in the CA as the crop residue retained leads to N mineralization/immobilization. Hence, the present research was aimed to determine the effect of CA and nitrogen managements on soil nitrogen, phosphorus and sulfur release and the enzymes involved in their mineralization. The results revealed that the CA practice significantly enhanced the mineral N, Olsen P and CaCl2-S release and the soil enzymes involved in this mineralization cycles compared to CT + R plots. Similarly, all the nitrogen fertilizer receiving subplots also recorded significantly higher mineral N, Olsen P and CaCl2-S release and the enzymes involved compared to the control. Furthermore, throughout the incubation period the Urea super granule + Greenseeker treatment significantly outperformed the RDN plot with respect to NO3-N and CaCl2-S release. Whereas, the Urea + Greenseeker treatment registered significantly higher NO3-N and CaCl2-S over RDN plot from 30 and 45 days after incubation, respectively. The NH4-N and Olsen P release had increasing trend up to 45 days after incubation and thereafter it decreased. In nutshell, the research emphasizes the significance of CA alongside optimum nitrogen management approaches in enhancing the soil enzymatic activities and nutrient mineralization. These outcomes hold significance for both farmers and researchers seeking ecologically sound and productive agricultural methods to enhance crop output and maintain soil quality.