农田N2O排放时空格局的形成机理和全球评估

准确理解全球农田氧化亚氮(N2O)排放时空格局是制定区域或全球N2O减排战略的科学基础。过去40年,国内外在农田N2O排放时空格局的形成机理和全球评估方面开展了大量研究。结合国内外现有实证研究进展,本文梳理了气候、土壤、农艺管理措施对农田N2O排放的空间格局和时间变化的多尺度影响,介绍了最新的排放因子、陆面过程模型、大气反演、升尺度等多模型方法及其全球评估成果。同时,提出了跨区域/样带观测、极端气候控制试验、陆面过程模型的区域预测能力、模型-数据融合系统等未来研究挑战,为推动全球氮循环的科学评估和气候智能型农业的国家建设提供科技支撑。

Spatiotemporal pattern of cropland nitrous oxide emissions: Driving factors and global assessment

The understanding of the spatiotemporal pattern of global cropland nitrous oxide emissions is critical foundation for designing mitigation strategies. In the past four decades, there were many studies that had focused on the underlying mechanisms and global assessment of global cropland nitrous oxide emissions. Here, the authors summarized previous studies related the scaling effects of climate, soil conditions, and agricultural management practices on the spatiotemporal pattern of global cropland nitrous oxide emissions. The authors introduced the research progress on multi-model ensembles(emission factor, land surface models, atmospheric inversion, and flux upscaling) and their application for global and regional assessment. Finally, the authors identified the research challenges on inter-regional observations, manipulative experiments related to extreme climate events, regional predictability of land surface models, and model-data assimilation. Addressing these challenges will enhance our mechanistic understanding of global nitrogen cycle and provide scientific supports for development of climate-smart agriculture.