CAJ | 학술논문

为了揭示水稻控制灌溉对稻麦轮作农田N2O排放的调控效应，该文对稻麦轮作农田N2O排放进行原位观测，分析稻麦轮作农田N2O排放对水稻控制灌溉水分调控的动态响应。结果表明，水稻灌溉模式对后茬冬小麦田N2O排放产生了显著的后效性影响，控制灌溉稻季农田N2O排放总量较常规灌溉稻季农田平均增加了136.9%（P<0.05），而稻季采用控制灌溉的麦季农田N2O排放总量较稻季采用常规灌溉的麦季农田平均减少47.1%（P<0.05）；稻季采用控制灌溉的稻麦轮作农田全年N2O排放总量平均为761.50 mg/m2，较稻季采用常规灌溉的轮作农田平均减少了1.0%，差异很小（P>0.05）。稻季采用控制灌溉的稻麦轮作农田N2O-N损失率为1.01%，稻季采用常规灌溉的轮作农田N2O-N损失率为0.98%。麦季N2O排放通量的峰值一般出现在施肥后伴随降雨时，降雨后7～10 d是麦季N2O剧烈排放的关键时期。水稻控制灌溉较常规灌溉没有增加稻麦轮作农田的N2O排放。研究结果为准确估算中国农田N2O排放量及制定N2O减排措施提供参考。
위료게시수도공제관개대도맥륜작농전N2O배방적조공효응，해문대도맥륜작농전N2O배방진행원위관측，분석도맥륜작농전N2O배방대수도공제관개수분조공적동태향응。결과표명，수도관개모식대후치동소맥전N2O배방산생료현저적후효성영향，공제관개도계농전N2O배방총량교상규관개도계농전평균증가료136.9%（P<0.05），이도계채용공제관개적맥계농전N2O배방총량교도계채용상규관개적맥계농전평균감소47.1%（P<0.05）；도계채용공제관개적도맥륜작농전전년N2O배방총량평균위761.50 mg/m2，교도계채용상규관개적륜작농전평균감소료1.0%，차이흔소（P>0.05）。도계채용공제관개적도맥륜작농전N2O-N손실솔위1.01%，도계채용상규관개적륜작농전N2O-N손실솔위0.98%。맥계N2O배방통량적봉치일반출현재시비후반수강우시，강우후7～10 d시맥계N2O극렬배방적관건시기。수도공제관개교상규관개몰유증가도맥륜작농전적N2O배방。연구결과위준학고산중국농전N2O배방량급제정N2O감배조시제공삼고。
Continuous emissions of greenhouse gases (GHGs) will cause further warming and changes of the climate system. Nitrous oxide (N2O) is an important GHG. Irrigation mode is an important factor in regulating N2O emissions from croplands. Controlled irrigation (CI) is one of the major water–saving irrigation practices, and has been widely applied. Compared with traditional irrigation (TI), CI leads to remarkable changes in soil properties and soil biochemical processes, which consequently induces changes in N2O emissions. Whether CI practiced during the rice season has subsequent effects on N2O emission during the following winter wheat season is worthy of further study. Thus, a field experiment was designed to study the effects of CI during the rice season on N2O emissions from the rice–winter wheat rotation systems, with TI as the control. The gas samples were collected by the static chamber technique. The chamber, consisting of 2 separate layers with the same size (0.5 m × 0.5 m × 0.6 m), was made of polyvinyl chloride. Samples were collected by 50 mL syringes, which were connected to chambers and sealed airbags through 3 stopcocks. Irrigation mode during the rice growing season had obvious subsequent effects on N2O emission from the following winter wheat growing season. Compared to TI, CI significantly increased the N2O emission during the rice growing season (P<0.05), but significantly decreased it during the wheat season (P<0.05). During the rice growing season, the mean of N2O emissions from the CI plots was 229.25μg/(m2·h), which was 1.66 times higher than that from the TI plots. During the winter wheat season, N2O emissions from the CI plots were generally lower than those from the TI plots. High N2O emissions from the CI plots were mainly observed after the regreening fertilizer application. Two or three peaks were observed from the CI plots in the middle and late stage of wheat growth, and the peak values were less than those from the TI plots. In the TI plots, N2O emissions were always high in the early stage of wheat growth and after the regreening fertilizer application, and were low during the overwintering period of wheat growth. Four peaks of N2O emissions were observed from the TI plots. During the winter wheat season,N2O emissions were closely related to rainfall. High N2O emissions were observed from 7 to 10 days after rainfall. Compared to TI, CI significantly increased the cumulative N2O emission in rice growing season by 136.9% (P<0.05), but decreased it in wheat growing season by 47.1% (P<0.05). Over the whole annual cycle, the cumulative N2O emission from the plots under the CI was 761.50 mg/m2, 1.0% lower than that under TI (P>0.05). During the 2009-2010 and 2010-2011 wheat growing season, the cumulative N2O emissions from the CI fields were reduced by 46.7% and 47.6% respectively, compared with those from the TI fields. The cumulative N2O emissions from the rotation systems under CI were 6.88 and 8.35 kg/ha in 2009–2010 and 2010–2011, respectively, reduced by 5.7% and increased by 3.2% respectively, compared with those from the TI fields. The N2O–N loss was used to measure the amount of N2O emissions from the croplands. During the rice growing season in 2009 and 2010, the mean N2O–N losses under CI were 0.97% and 1.13%, respectively, while the mean N2O–N losses under TI were 0.40% and 0.49%, respectively. During the 2009–2010 and 2010–2011 wheat season, the mean N2O–N losses in the CI plots were both 0.86%, while N2O–N losses in TI plots were 1.62% and 1.63%, respectively. Over the whole annual cycle, the mean N2O–N losses were 1.01% and 0.98% in CI and TI plots, respectively. These results suggest that controlled irrigation dose not increase the cumulative N2O emission from the rice-winter wheat rotation systems, compared to traditional irrigation.