大气氮沉降研究进展

含氮化合物从大气中移除并降落到地表的过程称为大气氮沉降(N deposition)，它是氮素生物地球化学循环中的重要环节。化石燃料燃烧、氮肥施用、畜禽养殖等人为活动，致使活性氮的排放量增加，这部分氮素最终以干/湿沉降的方式返回到地球表面，以营养源和酸源的形式介入陆地和水生生态系统，改变了氮素的自然循环。中国是全球氮沉降3大热点地区之一。在简要回顾大气氮沉降的研究历史后，综述了近年来国内外大气氮沉降的研究进展，主要包括：不同生态系统对氮沉降的响应、环境氮素损失的评估、氮沉降监测分析方法的改进、有机氮沉降研究与中国氮沉降现状，氮沉降纳入农田养分资源综合管理的前景及氮沉降监测网络的发展等方面。鉴于氮沉降研究的复杂性，建立全国性的监测网络，辅之以模型模拟将是今后关注的重点方向。

Research Progress in Atmospheric Nitrogen Deposition

Atmospheric nitrogen(N) deposition refers to the processes by which N components are removed from atmosphere and then deposited on the earth surface. Nowadays N deposition is well known to be one of key components of global N biogeochemical cycles. Along with the aggravated anthropogenic perturbation (fossil fuel combustion, nitrogen fertilizer application, livestock and poultry production, e.g.), large amount of reactive N (Nr) species are emitted into atmosphere and subsequently deposited back to global, terrestrial and aquatic ecosystems, existing as a source of nutrient and acid, where they have been altering the natural N cycling profoundly. Moreover, excessive anthropogenic Nr deposition may exert the direct or indirect detrimental environmental effects, e.g. soil acidification, water eutrophication, biodiversity degradation, human health issues, etc. Emerging from an agricultural benchmark to increasing industrialization and urbanization, China was identified as one of the three N deposition hotspots. This paper reflected on the research history of N deposition, in addition, several main research progresses were involved in: responses of different ecosystems to N saturated, economic cost assessment on N deposition, improvement on N monitoring and analysis, research progresses on organic N and current situation in China, consideration of N deposition into integrated cropland nutrient management and its perspective, and the last but not the least, the development of monitoring network presently. In view of the complexity of N research, establishing national monitoring network in parallel to modeling works should attract more attention in the future.