NITROGEN LOSS FROM ABOVE-GROUND PLANTSBY VOLATILIZATION

Water culture, soil culture and N2-labelled fertilizer were used to study gaseous nitrogen loss from plants by volatilization. The pots either with or without plants were placed into a self-made plastic growth chamber for trapping N2,N2O and NH3 released from plants. The chamber could be firmly sealed and special masures were adopted to avoid the contamination of the gasses for studies from soil and air as much as possible. The results obtained show that the plants did not release N2,but released N2O and NH3. However, the released N2O was little but the released NH3 was relatively high. The nitrogen loss by volatilization occurred at the later stage of plant growth. The results also show that there was great difference between the nitrogen reduction of the above-groung plants and the NH3 trapped from the chamber, the former being much higher than the later. In order to understand the fate of the reduced nitrogen, much more work with attention to different ways of the loss is needed in the future.