3.3 Contribution of microorganisms to N2O
emission
Compared with the control without biological inhibitors (control
treatment), the treatment with bacterial inhibitors (streptomycin
treatment) and fungal inhibitors (cycloheximide treatment) significantly
reduced soil N2O emission (P < 0.05) (Fig.
3a). The N2O emission after bacterial inhibitor
treatment was significantly higher than that after fungal inhibitor
treatment (P < 0.05), and significantly lower after fungal and
bacterial inhibitor treatment (P < 0.05). The
N2O production was reduced to 30.9% by fungal inhibitor
treatment, 45.4% by bacterial inhibitor treatment, and 23.7% by fungal
and bacterial inhibitor treatment as compared to that in the control
treatment. These results suggeste d that fungi may play a larger role in
N2O production in lawn soil.
Moreover, the contribution rate of fungi to N2O emission
was significantly higher than that of bacteria and other microorganisms
(P < 0.05) (Fig. 3b). Fungi contributed to 45% of total
N2O emission, while bacterial contribution only reached
68% of that of the fungi. This also indicated that the contribution of
fungi to N2O emission was significantly higher than that
of bacteria in lawn soil.