减氮施肥对春玉米-晚稻生产系统碳足迹的影响
俞祥群1姜振辉2王江怀2林景东2刘益珍2杨京平2*
(1浙江省杭州市农业科学研究院农作物(生态)研究所,杭州 310024;2浙江大学环境与资源学院,杭州310058)
摘 要 随着对气候变化和粮食安全的的日益认识,
低碳农业引起了人们的广泛关注.低碳
农业的研究需要综合考虑作物产量和温室气体排放,
改进氮肥管理可能有助于减缓作物生产
系统的温室气体排放,
同时实现对作物稳产甚至高产的需求.本试验利用生命周期法研究了
不同施氮量(150、225、300 kg N·hm-2)对春玉米-
晚稻轮作系统碳足迹的影响.结果表明:随
着氮肥用量增加,
两季作物生产过程中温室气体和碳足迹增加.在春玉米生产过程中,
氮肥生
产和施用引起的温室气体排放对碳足迹贡献最大,
占36.2% ~ 50.2%;而在晚稻生产中,
甲烷
的排放贡献最大,
占42.8% ~ 48.0%,
并且随氮肥用量增加甲烷排放增加.当氮肥施用量减少
25%(225 kg N·hm-2)和50%(150 kg N·hm-2)时,
春玉米生产的温室气体排放分别下降了
21.9%和44.3%,
碳足迹分别下降了 20.3% 和39.1%;晚稻生产的温室气体排放分别下降了
12.3%和20.4%,
碳足迹分别降低了 13.7%和16.7%.氮肥减量对春玉米产量无显著影响,
而晚
稻产量在 225 kg N·hm-2施肥量下最高.因此,
春玉米氮肥用量降低至 150 kg N·hm-2和晚稻
氮肥用量降低至 225 kg N·hm-2不仅能够保持作物高产,
而且还能大幅度降低作物系统的碳
足迹.
关键词 碳足迹;春玉米-
晚稻轮作;减氮施肥;温室气体排放
本文由杭州市农业科研自主申报项目(20180432B19)和国家重点研发计划项目(2016YFD0300203-4)资助 This work was supported by the Hang-
zhou Agricultural Research Independent Declaration Project (20180432B19 )and National Key Research and Development Program of China
(2016YFD0300203-4).
2018-12-03 Received,2019-03-20 Accepted.
*通讯作者 Corresponding author. E-mail:jpyang@ zju.edu.cn
Effect of reduced nitrogen fertilization on carbon footprint in spring maize-late rice produc-
tion system. YU Xiang-qun1,JIANG Zhen-hui2,WANG Jiang-huai2,LIN Jing-dong2,LIU Yi-
zhen2,YANG Jing-ping2* (1Institute of Crop (Ecology ),Hangzhou Academy of Agricultural
Sciences,Zhejiang Province,Hangzhou 310024,China;2College of Environment and Resource
Science,Zhejiang University,Hangzhou 310058,China).
Abstract:With the growing concerns on global climate change and food security,low carbon agri-
culture in food production attracts more attention. Low carbon agriculture needs to balance higher-
level crop yields and lower greenhouse gas emission in production process. Improving nitrogen mana-
gement may help mitigate greenhouse gas emission and achieve stable or higher crop yields in crop
production systems. In this study,we investigated the effects of nitrogen application rates (150,
225,300 kg N·hm-2)on the carbon footprint of spring maize-late rice rotation system in paddy
field using the life cycle assessment. The results showed that greenhouse gas emission and carbon
footprint increased with the nitrogen fertilizer application rates in both crops. Nitrogen fertilizer was
the most important contributor to carbon footprint of spring maize ecosystem,accounting for 36.2%-
50.2%. Methane emission increased with nitrogen fertilizer input and contributed the most to the
carbon footprint of late rice production,accounting for 42.8%-48.0%. When the nitrogen applica-
tion rate was reduced by 25% (225 kg N·hm-2)and 50% (150 kg N·hm-2),greenhouse gas
emission of maize production decreased by 21.9% and 44.3%,and the carbon footprint decreased
by 20.3% and 39.1%,respectively. Meanwhile,the greenhouse gas emissions of late rice decreased
by 12.3% and 20. 4%,and the carbon footprint of late rice decreased by 13. 7% and 16. 7%,
respectively. The reduction of nitrogen fertilizer rate had no significant effect on maize yield,with
the treatment of 225 kg N·hm-2rate holding the highest yield in late rice ecosystem. The treatment
应用生态学报 2019 年4月 第 30 卷 第 4期http:/ /www.cjae.net
Chinese Journal of Applied Ecology,Apr. 2019,30(4):1397-1403 DOI:10.13287 /j.1001-9332.201904.038