基于养分专家系统的农田养分管理技术在小麦玉米农田温室气体减排中的应用效果

Effects of nutrient management strategy of Nutrient Expert on greenhouse gas emission reduction in winter wheat-summer maize cropping system

为了评价基于养分专家系统(Nutrient Expert,简称NE)养分管理模式下的推荐施肥对农田环境效应的影响,对121个田间试验中基于NE养分管理模式和农民习惯管理模式下的农田温室气体排放量进行了分析。结果发现:NE养分管理模式在不降低作物产量的前提下,大幅度提高了农田氮肥偏生产力,显著降低了温室气体排放量。与农民习惯施肥处理相比,NE养分管理模式的N2O排放量在小麦和玉米季分别降低了60.8%和53.7%。而在总的农田温室气体排放当量中,NE养分管理模式的温室气体排放当量较农民习惯施肥处理(FP)在小麦和玉米季分别降低了40.8%和42.3%。农田温室气体排放当量与氮肥偏生产力间有显著的线性+平台关系,即在一定范围内温室气体排放量随着氮肥偏生产力的提高而降低。在本研究中,当排放量分别降低到2 350kg CO2eq/hm2(玉米)和1 888 kg CO2eq/hm2(小麦)时,随着氮肥偏生产力的增加温室气体排放量有趋于不变的趋势。总体来看,基于NE养分管理模式的推荐施肥技术在华北平原减少农田温室气体排放方面有很好的应用前景。

121 wheat and maize field experiments,including NE recommendation（ NE） and farmers＇ practices（ FP） treatments,were used in this research to evaluate the effects of Nutrient Expert（ NE） on grain yield and greenhouse gas（ GHG）emission reduction in wheat and maize production. The results showed that the NE strategies significantly reduced N fertilizer input and greenhouse gas emission in comparison with FP at same yield level. The N2 O emission rate for NE decreased by60. 8% and 53. 7% respectively than FP for wheat and maize. And the total Global Warming Potential（ GWP） for NE treatment was 40. 8% and 42. 3% lower than FP treatments for wheat and maize respectively. Significantly liner ＋ plateau correlations were found between GWP and the nutrient use efficiency of PFP-N in this research. With the increasing of the nutrient use efficiency of PFP-N,the GWP had the trend of decreasing. When the GWP reached 1 888 kg CO2 eq / hm2 and 2 350 kg CO2 eq / hm2 for wheat and maize respectively,the GWP had the trend of keeping at a certain level. This research showed the potential advantage of NE nutrient management strategies in greenhouse gas emission reduction in the North China Plain.