Effects of tillage depth on infiltration characteristics of two bangladesh soils having ploughpans

Abstract

Ploughpans, caused by puddling of soil for rice cultivation for years, are bound to affect soil water balance and the utilization of the stored soil water by dry-land crops. Loosening of the pan by increasing the plough depth is likely to increase utilization of sub-soil water and recharge of the soil profile. The effects of different tillage regimes on infiltration of two Bangladesh soils with ploughpans were studied. Cumulative infiltration rates were increased in both Sonatala and Modhupur soils owing to increase in depth of tillage. Cumulative infiltration and infiltration rates were much higher in the grey floodplain sandy loam soil compared with the red terrace clay loam soil. The cumulative infiltration of Sonatala soil in no-tillage, 7.5, 15.0 and 22.5 cm tillage depth plots were 18.8 cm in 400 min, 31.0 cm in 400 min, 36.3 cm in 300 min and 43.3 cm in 150 min, respectively. The total amount of water entering into Modhupur soil in 400 min was 14.3, 21.0, 35.5, 46.9 and 50.7 cm in no-tillage, 7.5, 12.5, 17.5 and 22.5 cm tillage depth plots, respectively. Results further revealed that although the initial infiltration was higher and different in different tillage treatments, it decreased with time and tended to be more or less similar for all the tillage depths at the end of the study period. This was true for both the soils.