Field validation of DNDC model for methane and nitrous oxide emissions from rice-based production systems of india
Field validation of DNDC model for methane and nitrous oxide emissions from rice-based production systems of india
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DOI：
10.1007/s10705-005-6111-5
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发表时间：
2006-02-01
影响因子：
3.1
通讯作者：
Adhya, T. K.
中科院分区：
文献类型：
--
作者：
Babu, Y. Jagadeesh;Li, C.;Adhya, T. K.
DNDC（反硝化和分解）模型进行了测试，对实验数据的甲烷和N2 O排放量在印度不同的地理位置的稻田。CH 4和N2 O排放模拟值与实测值吻合较好。所有地点观测到的甲烷排放量与模拟的甲烷排放量之间的差异在-11.6至62.5千克C/公顷（-1）季节（-1）之间。模拟和观测的季节性通量之间的差异大多小于20%的季节性通量的实地估计。N2 O累积排放量的观测值与模拟值之间的相对偏差为-237.8%至28.6%。然而，观测和模拟的CH 4和N2 O排放量的季节模式之间存在一些差异。该模型模拟了连续淹水稻田的零N2 O排放，而对阿拉哈巴德站点的CH 4排放模拟较差。在其他模拟情况下，模式均能较好地模拟不同土地管理方式下稻田温室气体排放的季节变化。该模型还模拟了所有站点的C和N平衡，包括其他气体通量，即CO2，NO，NO2，N-2和NH3的排放。CH 4敏感性试验表明，土壤质地和pH值显着影响CH 4排放。有机碳含量的变化对这些站点的CH 4排放有中等程度的影响。引入季中排水显著减少了CH 4排放。与DNDC一样，基于过程的生物地球化学建模可以帮助确定优化资源利用、提高生产力、缩小产量差距和减少不利环境影响的战略。
The DNDC (DeNitrification and DeComposition) model was tested against experimental data on CH4 and N2O emissions from rice fields at different geographical locations in India. There was a good agreement between the simulated and observed values of CH4 and N2O emissions. The difference between observed and simulated CH4 emissions in all sites ranged from -11.6 to 62.5 kg C ha(-1) season(-1). Most discrepancies between simulated and observed seasonal fluxes were less than 20% of the field estimate of the seasonal flux. The relative deviation between observed and simulated cumulative N2O emissions ranged from -237.8 to 28.6%. However, some discrepancies existed between observed and simulated seasonal patterns of CH4 and N2O emissions. The model simulated zero N2O emissions from continuously flooded rice fields and poorly simulated CH4 emissions from Allahabad site. For all other simulated cases, the model satisfactorily simulated the seasonal variations in greenhouse gas emission from paddy fields with different land management. The model also simulated the C and N balances in all the sites, including other gas fluxes, viz. CO2, NO, NO2, N-2 and NH3 emissions. Sensitivity tests for CH4 indicate that soil texture and pH significantly influenced the CH4 emission. Changes in organic C content had a moderate influence on CH4 emission on these sites. Introducing the mid-season drainage reduced CH4 emissions significantly. Process-based biogeochemical modeling, as with DNDC, can help in identifying strategies for optimizing resource use, increasing productivity, closing yield gaps and reducing adverse environmental impacts.