Abstract

                                Effect of tillage practices and organics on physical properties at different depths in an Alfisol having sub soil hard pan at shallow depth was studied in the field experiment with sorghum as the test crop. The bulk density of the soil reduced significantly due to chiseling and this effect was more pronounced in 15-30 and 30-45 cm depths, where the bulk density steeply reduced from 1.82 to 1.58 Mg m-1. Application of either farm yard manure or composted coir pith@12.5 t ha-1 appreciably reduced the bulk density over control, and their effects were found to be comparable. A steep increase in hydraulic conductivity was observed due to chiseling in 15 30 cm depth (0.32 to 2.78 cm h-1). No perceptible change was observed in the surface layer due to different tillage practices. The applied organics had a marked favourable effect on the hydraulic conductivity of the surface soil and on the pore size distribution. The pore size distribution of the soil also indicated the positive influence of chiseling in all the depths.

Key words : Tillage, Organics, Bulk density, Hydraulic conductivity. Pore size" distribution, Sorghum