氮肥减量深施对双季稻产量和氧化亚氮排放的影响  

Effects of reduction and deep placement of nitrogen fertilizer on rice yield and N_2O emissions from double cropping paddy field

作　　者：彭术 张文钊[2,3] 侯海军 王华[1] 陈安磊 魏文学[2,3] PENG Shu;ZHANG Wen-zhao;HOU Hai-jun;WANG Hua;CHEN An-lei;WEI Wen-xue(College of Bioscience and Biotechnology,Hunan Agricultural University,Changsha 410128,China;Key Laboratory of Agro-ecological Processes in Subtropical Region,Institute of Subtropical Agriculture,Chinese Academy of Sciences,Changsha 410125,China;Taoyuan Station of Agro-ecology Research,Institute of Subtropical Agriculture,Changsha 410125,China)

机构地区：[1]湖南农业大学生物科学技术学院,长沙410128 [2]中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,长沙410125 [3]桃源农业生态试验站,长沙410125

出　　处：《生态学杂志》2019年第1期153-160,共8页Chinese Journal of Ecology

基　　金：科技部国家重点研发计划项目(2016YFD0200307和2017YFD0301504);科技部国家科技支撑计划项目(2014BAD14B01)资助

摘　　要：稻田生态系统是重要的N_2O排放源,氮肥施用是促进稻田N_2O排放的主要影响因素之一。研究合理的氮肥管理措施对减少稻田N_2O排放和维持水稻高产具有重要意义。本研究以湖南典型红壤双季稻田系统为对象,以常规施氮(CF,早、晚稻施氮量均为150kg N·hm-2)为对照,在氮肥深施条件下,设置3个减氮水平(分别减氮30%、23%和16%),研究氮肥减量深施对双季稻产量及N_2O排放的影响,连续2年的田间试验。结果表明:通过化肥点状深施到土表下约7 cm,减少30%氮肥用量可以显著提高双季稻有效穗数和实粒数,使双季稻平均增产5%;氮肥减量深施可显著降低双季稻田的N_2O排放;减氮30%处理的早、晚稻季N_2O累积排放量较CF处理降低了57%和72%;氮肥减量深施还影响双季稻田N_2O排放模式; CF处理的N_2O排放峰值出现在分蘖期,而氮肥减量深施处理除在双季稻返青期和成熟期略有N_2O排放,其余生育期间几乎无N_2O排放。通过氮肥深施,适当减少氮肥施用量可以维持双季稻产量稳定和降低双季稻田N_2O排放。Paddy field is an important N2O emission source. Nitrogen fertilization is one of the main influencing factors for N2O emissions from paddy field. Therefore,it is significant to clarify reasonable nitrogen fertilization to maintain high rice yield and reduce N2O emissions. With the conventional fertilization as control( CF,150 kg N · hm^-2in the early and late season rice,respectively),three nitrogen application rates( nitrogen fertilizer reduction 30%,23%,and16%,respectively) were set up with deep placement to examine the effects of reduction and deep placement of nitrogen fertilizer on rice yield and N2O emissions from double cropping paddy field.The results of a two-year field experiment showed that,through applying chemical fertilizers at a depth of 7 cm in soil,nitrogen fertilizer reduction 30% significantly increased the numbers of productive ear and grains and increased grain yield by 5%. Reduction and deep placement of nitrogen fertilizer obviously reduced N2O emissions from double cropping paddy field. Compared with CF treatment,nitrogen fertilizer reduction 30% significantly diminished the accumulative emission of N2O by 57% and 72% in the early and late growing season,respectively. In addition,reduction and deep placement of nitrogen fertilizer changed the N2O emission pattern. The N2O emission peak appeared at the tillering stage in the CF treatment,while there was only low N2O emission at the seeding establishment and ripening stages in the treatments with reduction and deep placement of nitrogen fertilizer. In conclusion,rational nitrogen fertilizer reduction combined with deep placement can maintain grain yield and mitigate N2O emissions from double cropping paddy field.

关 键 词：深施 N2O排放 双季稻田 铵态氮 硝态氮 

分 类 号：S511.42[农业科学—作物学]