施用生物炭对寒地水稻生长与稻田温室气体排放的影响及其机理研究

CH4 and N2O are recognized as the two important greenhouse gases that are causing global warming. Paddy field system is an important source of greenhouse gas emissions. Biochar is a new type of organic fertilizer and is focused. Currently the mechanism of the influence of biochar on CH4 and N2O emissions in paddy field is not clear. Meanwhile, the effects of biochar application on CH4 and N2O emissions under the different soil fertilities and cultivars are also not well documented. Especially, the effects and mechanisms of biochar application and nitrogen fertilizer integrated management on emissions of CH4 and N2O in cold region rice in Northeast China are scarcely reported. This research will through macroscopic and microcosmic analysis base on japonica rice in cold region. In this study, the effect of biochar on emissions of CH4 and N2O will be investigated under different soil fertilities and varieties, so as to reveal the effect of biochar on CH4 and N2O emissions. Moreover, the root morphology, physiological and biochemical characteristics, soil carbon and nitrogen cycling characteristics and cell biological properties of Aerenchyma tissue of CH4 and N2O emissions in rice paddy under the biochar application and nitrogen fertilizer integrated management will be examined, so as to reveal the mechanism of the physiological and biochemical and molecular of CH4 and N2O emissions. It may be expected that the regulation technology theory of greenhouse gas emission by biochar application in rice paddy could be understood and the results may also provide scientific reference for comprehensive regulation and international negotiation of paddy field carbon sequestration and increase soil fertility and efficiency.

甲烷和氧化亚氮是引起全球变暖的两种重要的温室气体。稻田系统是重要温室气体排放源。生物炭作为一种新型有机肥备受各界关注，目前有关其对稻田甲烷和氧化亚氮排放的研究较少，不同土壤肥力和品种类型间施用生物炭对甲烷和氧化亚氮排放的研究也非常缺乏，而生物炭和氮肥对稻田甲烷和氧化亚氮排放的互作效应及机理尚鲜见报道，尤其是针对我国东北寒地稻区的研究更是甚少。本项目拟以寒地粳稻为研究对象，通过宏观与微观相结合的手段，研究生物炭在土壤肥力和品种间的影响差异，揭示生物炭对土壤肥力和品种间温室气体排放的作用效果；系统研究生物炭与氮肥管理下，稻田甲烷和氧化亚氮排放的根系形态、生理生化特征、土壤碳氮循环以及通气组织的细胞生物学性状等，揭示生物炭与氮肥配施对甲烷和氧化亚氮排放的生理生化和分子机理。本研究结果可阐明生物炭对稻田温室气体排放的调控理论与技术，为我国稻田固碳减排增肥增效的综合调控和国际谈判提供科学依据。

甲烷和氧化亚氮是引起全球变暖的两种重要的温室气体。稻田系统是重要温室气体排放源。生物炭作为一种新型有机肥备受各界关注，本项目以寒地粳稻为研究对象，通过宏观与微观相结合的手段，研究结果表明，在高肥力下施用1.5t/hm2的生物炭较低肥力下不施生物炭的水稻产量显著提高23.3%，CH4排放降低7.7%，综合温室效应降低6.1%，温室气体排放强度降低22.7%；不同肥力下施用生物炭的土壤有效磷和速效钾含量均显著增加。中等肥力下施用生物炭的土壤全氮含量显著增加17.9%。在中等肥力和高肥力条件下施用生物炭的土壤有机质含量分别显著提高15.5%和15.9%。高秆、耐高氮、大穗型和根系发达品种具有较高的产量，施用生物炭使不同品种的产量显著提高7.7%。高秆、矮秆和根系发达品种的CH4排放、综合温室效应和温室气体排放强度均较低；施用生物炭使各个品种的CH4排放、综合温室效应和温室气体排放强度分别显著降低23.7%、23.5%28.4%。与低氮下不施生物炭相比，常规氮肥下施用1.5t/hm2生物炭产量平均增加21.7%，具有较低的CH4排放、综合温室效应和温室气体排放强度；使土壤可溶性碳含量增加，铵态氮含量降低，硝态氮含量增加；使根系ATP合酶活性显著降低20.8%，过氧化氢酶活性显著增加36.4%，硝酸还原酶活性增2.0%；使茎秆细胞层数增加，细胞形状更加规则，细胞的大小增加，表皮组织和基本组织厚度显著增加，维管束的长度较短。本研究结果阐明了生物炭对稻田温室气体排放的调控理论与技术，为我国稻田固碳减排增肥增效的综合调控和国际谈判提供科学依据。