摘要:氧化亚氮（N2O）是主要的温室气体之一，对大气环境质量与全球气候变化具有重要的影响。N2O排放不仅增加温室效应，同时也会导致陆地生态系统氮损失与平流层臭氧消耗。长期以来土壤被认为是陆地生态系统N2O的主要排放源，但近年来越来越多的证据表明，植物可能是陆地生态系统N2O排放的另一重要来源。近年来有关植物排放N2O的报道逐年增多，但对植物排放N2O的途径及其调控机制方面还缺乏文献综述。本文首先在总结长期以来人们普遍认为的N2O源与汇的基础上，提出陆地植物可能是另一个尚未被广泛认可的重要的N2O的排放源。植物排放N2O可能有两种潜在途径：1）植物作为土壤中通过微生物产生的N2O的运输通道，2）植物通过自身代谢或内生菌的作用产生N2O并排放到大气中。然后分析了关键因素（养分、光照、温度和植物器官及生长阶段）对植物排放N2O的影响机制。最后指出未来需进一步探明植物体内产生N2O的具体途径及其对全球N2O排放的贡献，重点是探明植物自身的生理生化过程以及与其伴生、共生的微生物在N2O产生中的作用。
关键词:植物/
氧化亚氮/
陆地生态系统/
反硝化/
氮循环
Abstract:Nitrous oxide (N2O) significantly affects atmospheric environment quality and global climate change. N2O emissions intensify greenhouse effects and lead to terrestrial reactive nitrogen loss and stratospheric ozone consumption. Soil is considered the primary source of N2O emissions from terrestrial ecosystems. However, recent studies indicate that plants also contribute to terrestrial ecosystem N2O emissions. Plant N2O emissions have been increasingly studied over the last decade, but a review of the N2O plant emission pathway and regulatory mechanisms is lacking. This paper summarized the traditionally recognized N2O sources and sinks, and proposed that terrestrial plants may be another unrecognized N2O source. Two potential plant N2O emission pathways were analyzed: 1) soil microorganisms produce N2O which is then emitted by plants or 2) plants produce N2O via metabolism or the action of endophytes. Subsequently, key factors were analyzed (e.g., nutrients, light, temperature, plant organs, and growth stage) to determine the effects on and mechanisms of N2O plant emissions. This study suggests that specific plant N2O production pathways and their contributions to global N2O emissions should be explored, with a focus on the physiological and biochemical processes of plants and the role of the symbiotic microorganisms in N2O production.
Key words:Plant/
Nitrous oxide/
Terrestrial ecosystems/
Denitrification/
Nitrogen cycle
PDF全文下载地址:
http://www.ecoagri.ac.cn/article/exportPdf?id=33217d1c-05f3-4864-a5f2-b6bb2ba4f46b
