| Budget Amount *help |
¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000)
Fiscal Year 2014: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
Fiscal Year 2013: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
Fiscal Year 2012: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
|
|---|
| Outline of Final Research Achievements |
The objective of this study was to clarify the mechanisms how the emission of nitrous oxide (N2O) decreased by the annual applications of farmyard manure (FYM) with appropriate reduction in synthetic fertilizer rate. The denitrification enzyme activity of soil in the grassland receiving FYM plus synthetic fertilizer was greater in comparison with the grassland receiving only synthetic fertilizer, however, the production ratio of N2O/N2+N2O in the process of denitrification was smaller in the former grassland. This reduction was considered to be the primary factor to reduce the N2O emission from grassland. The reduction in the production ratio of N2O/N2+N2O was considered to be due to the higher soil pH derived from the surface application of FYM and reduction in synthetic fertilizer rate. The appropriate reduction in the application rate of synthetic fertilizer also reduced nitrate in the soil and considered to be the secondary factor to reduce the N2O emission from grassland.
|
