Description:
Using a static system of ammonia sorbers, the extent of ammonia loss from surface-applied urea materials of different pellet sizes was studied under field conditions. Observations made at two different sites revealed that during the initial stage of exposure the gaseous ammonia loss was significantly retarded by increasing the pellet size. On extending the period of exposure to 20 and 30 days, respectively, this difference in the cumulative ammonia loss levelled out or even became negative.