中国主要旱地农田N_2O背景排放量及排放系数特点  

Characteristics of Background Emissions and Emission Factors of N_2O from Major Upland Fields in China

作　　者：徐玉秀[1,2] 郭李萍[2] 谢立勇[1] 云安萍 李迎春[2] 张璇[1] 赵迅[1] 刁田田 

机构地区：[1]沈阳农业大学农学院,沈阳110161 [2]中国农业科学院农业环境与可持续发展研究所,北京100081

出　　处：《中国农业科学》2016年第9期1729-1743,共15页Scientia Agricultura Sinica

基　　金：国家"十二五"科技支撑计划(2013BAD11B03);国家自然科学基金(31272249;31071865)

摘　　要：【目的】收集中国已发表的旱地农田N_2O排放田间监测文献并建立数据库,以此为基础解析中国主要旱地农田(小麦地、玉米地、蔬菜地)的N_2O背景排放值(不施肥情况下土壤的N_2O排放量)和排放系数(EF)及影响因子,为估算区域温室气体清单和提出相应的减排策略提供数据支持。【方法】利用亚组归类和回归分析等方法对主要类型旱地农田N_2O背景排放量的影响因子(如土壤全氮含量和土壤碳氮比)及影响EF的因子(如氮肥用量及肥料类型——硝化抑制剂和缓控释肥)进行分析。【结果】(1)中国旱地农田N_2O背景排放量为0.70—3.14 kg N_2O-N·hm^(-2);小麦地和夏玉米地的N_2O背景排放量和蔬菜地的N_2O日背景排放量均随土壤全氮含量增加而增加,并随土壤碳氮比的增加而降低,灌溉促进小麦地N_2O背景排放量增加;(2)EF随着无机氮肥用量的增加而增加,不同作物种植类型农田的EF大小依次为蔬菜地(0.61%—1.13%)>夏玉米地(0.50%—0.68%)>春玉米地(0.35%—0.40%)>小麦地(0.22%—0.36%);夏玉米地的EF是小麦地的2倍左右;(3)使用不同种类硝化抑制剂后氮肥的EF均有不同程度的降低,EF降低了34%—60%,EF降低程度依次为:DCD+HQ(58.9%)>NBPT+DCD(52.9%)>DMPP(51.1%)>NBPT(44.1%)>吡啶(39.5%)>DCD(38.9%);硝化抑制剂降低EF的效果在不同旱地农田的表现为:小麦地(60.0%)>蔬菜地(50.6%)>春玉米地(39.6%)>夏玉米地(34.7%);(4)与常规尿素相比,不同类型缓控释肥使得EF降低了15.9%—78.9%,降低次序依次为:长效碳酸氢铵(78.9%)>聚合物包膜尿素(59.8%)>脲甲醛(53.4%)>树脂包膜尿素(44.9%)>硫磺包膜尿素(30.6%)>钙镁磷肥包膜尿素(15.9%);缓控释肥降低EF的效果在不同农田表现为:蔬菜地(78.4%)>春玉米地(58.2%)>小麦地(49.2%)>夏玉米地,控释肥在降低夏玉米地EF的作用较小。【结论】旱地农田N_2O排放主要受土壤养分状况(全氮含量和碳氮比)和管理措施(灌溉和施�【Objective】Published literatures regarding to N2O emissions from upland fields in China were collected to establish a dataset. The established database was used to analyze the N2O background emissions（emission from soil without fertilization）, emission factors（EFs） and associated factors influencing the N2O emissions from major upland fields（for example wheat fields, maize fields and vegetable fields） in China. The results will provide supports for estimating regional N2O emission inventory and provide appropriate mitigation strategies.【Method】Subgrouping analysis and regression analysis were used to analyze the factors which influence N2O background emissions（for example the soil nitrogen content and C﹕N ratio of the soil） and EFs（for example the nitrogen application level and fertilizer types such as nitrification inhibitors and slow release or controlled release fertilizers）.【Result】（1） The N2O background emissions from upland fields ranged between 0.70 and 3.14 kg N2O-N·hm^-2. Either N2O background emissions from wheat and summer maize fields or daily N2O background emissions from vegetable fields increased with increasing soil total N（TN） while decreased with the increasing of soil C﹕N ratio. Irrigation could promote the N2O background emissions from wheat fields.（2） EFs increased with increasing N application rate and its value was ranked in the following order： vegetable fields（0.56%-0.61%） 〉summer maize fields（0.50%-0.68%） 〉spring maize fields（0.35%-0.40%） 〉wheat fields（0.22%-0.36%）. EFs from summer maize fields were two times higher than those from wheat fields.（3） Nitrification inhibitors could decrease N2O EF by 34%-60% ranking in the order： DCD＋HQ（58.9%）〉NBPT＋DCD（52.9%）〉DMPP（51.1%）〉NBPT（44.1%）〉Pyridine（39.5%）〉DCD（38.9%）. The effects of different nitrification inhibitors on EF decline were varied in different fields ranking in the order： wheat fields（60.0%）〉vegetable fields（50.

关 键 词：旱地农田 N2O背景排放 N2O排放系数 氮肥用量 硝化抑制剂 缓控释肥 

分 类 号：S181[农业科学—农业基础科学]