我国农田氧化亚氮排放的时空特征及减排途径  

Spatiotemporal Characteristics and Reduction Approaches of Farmland N_(2)O Emission in China

作　　者：严圣吉 尚子吟 邓艾兴[1] 张卫建[1,2] Yan Shengji;Shang Ziyin;Deng Aixing;Zhang Weijian(Institute of Crop Sciences,Chinese Academy of Agricultural Sciences,Beijing 100081,China;Center for Carbon Neutrality in Agriculture and Rural Region,Chinese Academy of Agricultural Sciences,Beijing 100081,China)

机构地区：[1]中国农业科学院作物科学研究所,北京100081 [2]中国农业科学院农业农村碳达峰碳中和研究中心,北京100081

出　　处：《作物杂志》2022年第3期1-8,共8页Crops

基　　金：现代农业产业技术体系建设专项(绿肥,CARS-22);中国科学院学部咨询评议重点项目(2021-SM01-B-008);中国农业科学院科技创新工程(Y2021YJ02,CAAS-XTCX2016008)。

摘　　要：氧化亚氮(N_(2)O)是全球第三大温室气体,农田生态系统是人为N_(2)O排放的重要来源,约占全球人为排放的30%。明确我国农田N_(2)O的排放特征、关键过程与影响因子,有助于因地制宜制定减排技术途径及行动方案。氮肥施用是农田N_(2)O排放的关键因子,国家统计数据发现,我国农田氮肥用量在2001-2007年呈上升趋势,之后趋于稳定,2014年开始下降,其中华东地区用量最高;农田N_(2)O排放总量也于2015年达到最高点,之后出现下降态势,总体呈现南高北低的特征。文献综合表明,农田N_(2)O排放主要由土壤反硝化过程主导,人为氮素添加是决定排放高低的首要影响因子。基于上述结果,在选用氮高效作物品种降低土壤N_(2)O排放的前提下,华东等施肥量高的地区可采取优化施肥比例、增施缓控释肥等途径,实现氮肥增效减量减排;在设施农地和果园等田间设施条件较好的农田,可采用水肥一体化滴灌等增效减排措施;在作物多熟种植地区,除了氮肥减量减排外,还可增加豆科作物布局,采用禾豆轮作等减排措施。最后,对农田N_(2)O减排的科技创新和政策创设等方面提出了一些建议,包括完善农田N_(2)O减排理论、创新智慧农业及高效施肥技术、健全碳监测评价体系以及碳减排激励政策与机制等,助力尽早实现我国碳达峰与碳中和目标。Nitrous oxide(N_(2)O)is the world's third-most-polluting greenhouse gas,and the farming ecosystem is a major source of anthropogenic N_(2)O emissions,accounting for roughly 30%of global anthropogenic N_(2)O emissions.Clarifying the N_(2)O emission characteristics of Chinese farms,as well as describing the key processes and main influencing factors,will aid in the exploration of technical emission reduction options and the development of an action plan.The main source of N_(2)O emissions from cropland is nitrogen fertilizer application.According to national statistics,the amount of nitrogen fertiliser used in China grew from 2001 to 2007,then remained consistent until 2014,when it began to fall,with the highest application rate in East China.Cropland N_(2)O emission in China peaked in 2015,and then gradually declined,the highest emission exiting in South and the lowest in North China.According to the literature analysis,this study further clarified that farmland N_(2)O emissions were mainly dominated by soil denitrification process,and anthropogenic nitrogen addition was the first prominent factor to farmland N_(2)O emissions.Based on the above findings,on the premise of selecting crop cultivars with nitrogen high efficiency and low soil N_(2)O emission,this study put forward some targeted emission reduction approaches.In areas with high N application rate,for example,in East China the proportion of fertilizer could be adjusted and controlled releasing fertilizers could be applied.In areas with good facility in irrigation and fertilization,such as facility farmland and orchard,fertigation technique with drip irrigation could be adopted.In areas with multiple cropping,crop rotation with legume or green manure crops could be used to reduce N_(2)O emission.Finally,some suggestions of scientific and technological innovations and policy making for N_(2)O emission reduction were provided in this study,including innovations of N_(2)O mitigation theory,smart technology of fertilization,carbon monitoring and evaluation sys

关 键 词：作物生产 气候变化 氧化亚氮 关键过程 影响因素 减排途径 

分 类 号：X71[环境科学与工程—环境工程]