|| 要旨トップ | 目次 |
|日本生態学会第59回全国大会 (2012年3月，大津) 講演要旨
一般講演（ポスター発表） P3-279A (Poster presentation)
We conducted field experiment to investigate the effect of lime-nitrogen on nitrification and N2O emission in fertilized soils, and soil incubation experiment was also conducted for further analysis of lime-nitrogen effect. We compared four nitrogen fertilizer treatments: CF (chemical fertilizer), LN100 (application of all N fertilizer as lime-nitrogen), LN50 (application of 50% of N as lime-nitrogen and the remainder as chemical fertilizer), and CFD (chemical fertilizer with DCD) in a field experiment. In a soil incubation experiment, two nitrogen treatments were also studied: CF treatment and lime-nitrogen treatment. Soil nitrification activity was lower in the LN100, LN50, and CFD plots than in the CF plot. We found an apparent decrease in N2O emission rate between 7 and 14 days after fertilization in the LN100, LN50, and CFD plots compared with that in the CF plot. This period of decrease in N2O emission rate paralleled that when DCD was detected in the topsoil layer of the former three plots. Moreover, correlation analysis suggested that the application of lime-nitrogen affects N2O emission through controlling both the first (NH4+ to NO2−) and second (NO2− to NO3−) soil nitrification reactions, whereas DCD blocks only the first nitrification reaction.