LEAF ABSORPTION OF ATMOSPHERIC AMMONIA EMITTED FROM PIG SLURRY APPLIED BENEATH THE CANOPY OF WINTER-WHEAT

Absorption of volatilized ammonia after application of slurry onto the soil surface (sand) between rows of a wheat crop was studied in two e xperiments. The slurry was labelled with N-15-NH4. During seven days t he accumulated gaseous N loss from the slurry varied from 6.9 to 11.1 g N m-2. In April ammonia losses from slurry applied beneath a 5 cm hi gh wheat crop were equal to losses from slurry applied to a fallow, bu t 2.2% of the lost atmospheric ammonia was taken up by the leaves. In May ammonia loss from slurry applied between the rows of a 43 cm high crop was reduced by 6% compared to the loss from fallow, because of a reduced transfer of ammonia from the slurry to the air. Of the emitted ammonia 3.3% was absorbed by the canopy.