Presenter: Kimura Sonoko Dorothea GHG. Tokyo University of Agriculture and Technology

1. Methane and Nitrous Oxide Emissions from Paddy Rice Fields in Indonesia - Comparison of SRI and surrounding conventional fields - Tokyo University of Agriculture and Technology: Dr. KIMURA Sonoko Dorothea SRI Experiment Plot +Farmers Field Tabo-Tabo Jampue Langunga Penarungan Sungsang

5. Lombok SRI field （ Nippon Koei ） SRI Non-SRI 08/03/20

6. Methane Flux CH 4 Flux (mg C m -2 h -1 ) Error bar stands for standard deviation

7. Nitrous Oxide Flux N 2 O Flux (μg N m -2 h -1 ) Error bar stands for standard deviation

8. CH 4 flux from intermittent irrigation Figure 2. Effect of water management on CH4 emission from a rice paddy field. The arrows indicate period of midseason drainage in the intermittent irrigation plot and the timing of final drainage in both of the plots. ( Yagi et al. 1997 ）

9. Influencing Parameters Days after transplanting Straw number Time of day CH 4 flux (mg C m -2 h -1 ) Jampue

10. Influencing Parameters Days after transplanting Straw number Time of day CH 4 flux (mg C m -2 h -1 ) Jampue Logging

11. Conclusions Problems Conventional Fields? Almost same planting density Intermittent irrigation Main difference: Seedling age Measuring of CH 4 and N 2 O flux Survey: March 20-23 Emission of gas is influenced by: Irrigation timing Time of day Growth stage

12. Conclusion CH 4 Flux Water status at the time of sampling had a greater influence on CH 4 flux than did the difference between SRI and conventional methods. However, since SRI fields tend to be drained, CH 4 flux tended to be higher in conventional fields. Highest CH 4 emission was found during early growing stages with conventional methods. N 2 O Flux High variability. Unexpected negative flux in some fields. SRI fields tended to emit more N 2 O than conventional fields, but the values are in the range found for conventional paddy fields (FM Honmachi 2007; total emission 0-0.2 kg N ha -1 ) .