RATE OF CHANGE OF pH IN SOME ACID SOILS DUE TO LIMING

Lime at the rate of 0, 3000, 6000, 12,000 and 24,000 pp2m was applied to four acid soils and allowed to incubate for a period of 140 days. The rate and extent of change in pH was followed.In all four soils the rate of reaction was very rapid and most of the increase in pH was obtained within 3 days after application. At all rates of liming in the four soils there was a general decrease in pH following the peak obtained within the first 30 days.It was also found that the rate of change in pH of a soil that had been limed was greatly influenced by the moisture content. The change in pH was much more rapid and extensive at 25 per cent moisture than at 10 per cent.