中国农业科学 ›› 2020, Vol. 53 ›› Issue (22): 4634-4645.doi: 10.3864/j.issn.0578-1752.2020.22.010

• 土壤肥料·节水灌溉·农业生态环境 • 上一篇    下一篇

生物炭与无机氮配施对稻田温室气体排放及氮肥利用率的影响

向伟1,王雷1,刘天奇1,李诗豪1,翟中兵3,李成芳1,2,*()   

  1. 1 华中农业大学植物科学技术学院/农业农村部长江中游作物生理生态与耕作重点开放实验室,武汉 430070
    2 长江大学/湖北省主要粮食作物 协同创新中心,湖北荆州 434023
    3 鄂东南现代农业展示中心,湖北武穴 435415
  • 收稿日期:2020-03-21 接受日期:2020-05-28 出版日期:2020-11-16 发布日期:2020-11-28
  • 通讯作者: 李成芳
  • 作者简介:向伟,E-mail: 754771491@qq.com
  • 基金资助:
    “十三五”国家重点研究计划(2017YFD0301403);国家自然科学基金(31671637);湖北省自然科学基金(2018CFB608)

Effects of Biochar Plus Inorganic Nitrogen on the Greenhouse Gas and Nitrogen Use Efficiency from Rice Fields

XIANG Wei1,WANG Lei1,LIU TianQi1,LI ShiHao1,ZHAI ZhongBing3,LI ChengFang1,2,*()   

  1. 1 College of Plant Science and Technology, Huazhong Agricultural University/Key Laboratory of Crop Physiology, Ecology and Cultivation in the Middle Reaches of the Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan 430070
    2 Yangtze University/ Collaborative Innovation Center of Major Grain Crops in Hubei Province, Jingzhou 434023, Hubei
    3 Modern Agriculture Exhibition Center in Southeast Hubei Province, Wuxue 435415, Hubei
  • Received:2020-03-21 Accepted:2020-05-28 Online:2020-11-16 Published:2020-11-28
  • Contact: ChengFang LI

摘要: 【目的】生物炭作为比表面积大、富含有多种营养元素的一种物质已被广泛应用于农业生产。弄清生物炭与化肥氮配合施用对稻田温室气体排放和氮肥利用率的综合影响,为合理使用生物炭提供科学依据。【方法】在武穴市花桥镇进行两年大田试验,设置4个处理,即不施氮肥(CK)、常规施氮(180 kg·hm -2)(IF)、常规施氮+10 t·hm -2生物炭(IF+C)、减氮30%+10 t·hm -2生物炭(RIF+C)。采用静态箱-气相色谱法对2018和2019年水稻生长季节稻田CH4和N2O排放通量进行监测,并测定水稻产量,探讨生物炭配施不同量无机氮对稻田CH4和N2O排放、水稻产量以及氮肥利用率的影响。【结果】(1)稻季CH4和N2O排放呈现明显的季节性变化规律。CH4排放峰值主要出现在分蘖期和齐穗期,N2O排放峰值主要出现在氮肥施用和排水后。2018和2019年稻季各处理CH4排放通量分别为0.01—48.97 mg·m -2·h -1和0.36—18.08 mg·m -2·h -1,N2O排放通量分别为-0.002—0.17 mg·m -2·h -1和0.01—0.28 mg·m -2·h -1。2018年各处理CH4和N2O的平均排放通量分别为6.17—7.16 mg·m -2·h -1和0.02—0.04 mg·m -2·h -1,2019年的分别为5.16—5.83 mg·m -2·h -1和0.05—0.08 mg·m -2·h -1。(2)与CK相比,无机氮肥的施用对CH4排放没有影响,但显著提高了N2O排放,增幅为32.6%—113.0%。与IF处理相比,生物炭与无机氮配施(IF+C、RIF+C)显著降低N2O排放,在2018年降幅为33.4%—43.1%,2019年为37.0%—39.5%,但对CH4排放的影响不显著,因此对全球增温潜势的影响不显著。生物炭与无机氮配施处理IF+C与RIF+C间CH4和N2O排放差异不显著。CH4排放是综合增温潜势(GWP)的主要贡献者,对GWP的贡献达84.4%—95.2%。(3)氮肥施用显著提高水稻产量,增幅达4.0%—6.0%。与IF处理相比,生物炭处理(IF+C、RIF+C)显著增加水稻产量,增幅达9.9%—11.9%。生物炭与无机氮配施处理IF+C与RIF+C间水稻产量差异不显著。与IF处理相比,IF+C、RIF+C处理氮肥利用率显著增加了7.7%—8.1%,且RIF+C的氮肥偏生产力两年分别增加了57.1%、52.3%。【结论】减氮30%配施生物炭能有效地降低稻田N2O排放、增加水稻产量、提高氮肥利用率,是一项可持续的农艺措施。但生物炭对稻田温室气体减排的效应还要进一步研究探讨。

关键词: 生物炭, CH4, N2O, 增温潜势, 氮肥利用率, 水稻产量

Abstract:

【Objective】Biochar has been widely used in agricultural production due to large specific surface area and high concentrations in a variety of nutrients. The aim of this study was to investigate effects of biochar plus Inorganic nitrogen on the greenhouse gas and nitrogen use efficiency from rice fields, so as to provide a scientific basis for the proper use of biochar.【Method】A 2-years field trials in Huanqiao town Wuxue city were set up to investigate the effects of biochar combined with different amounts of inorganic nitrogen on CH4 and N2O emissions, grain yield and nitrogen use efficiency from paddy fields. Four treatments included no nitrogen (CK), conventional inorganic nitrogen (180 kg·hm -2) (IF), conventional inorganic nitrogen+10 t·hm -2 biochar (IF+C), and 30% reduction of inorganic nitrogen+10 t·hm -2 biochar (RIF+C). The CH4 and N2O emission fluxes from paddy soils were determined by static chamber-gas chromatography method, and the grain yield was also determined.【Result】(1) There were obvious seasonal trends in CH4 and N2O emissions during the rice growing seasons of 2018 and 2019. The CH4 fluxes peaked at the tillering and heading panicle stages, and the N2O fluxes peaked just after N fertilization and field drainage. The CH4 fluxes ranged from 0.01 mg·m -2·h -1 to 48.97 mg·m -2·h -1in 2018 and 0.36 mg·m -2·h -1 to 18.08 mg·m -2·h -1in 2019, and the N2O fluxes were -0.002-0.17 mg·m -2·h -1 in 2018, and 0.01-0.28 mg·m -2·h -1in 2019. Average CH4 fluxes were 6.17-7.16 mg·m -2·h -1in 2018 and 5.16-5.83 mg·m -2·h -1in 2019, and average N2O fluxes were 0.02-0.04 mg·m -2·h -1in 2018 and 0.05-0.08 mg·m -2·h -1 in 2019. (2) Compared with CK, the application of inorganic nitrogen fertilizers did not affect CH4 emissions, but increased N2O emissions by 32.6%-113.0%. Compared with IF, biochar treatments (IF+C and RIF+C) did not affect CH4 emissions, but significantly decreased N2O emissions by 33.4%-43.1% in 2018 and by 37.0%-39.5% in 2019. There was no difference in global warming potential (GWP) between IF and biochar treatments. No significant differences in CH4 and N2O emissions were observed between IF+C and RIF+C. CH4 emissions played in a dominant in GWP, accounting for 84.4%-95.2% of the seasonal GWP. (3) Nitrogen fertilization significantly increased rice grain yields by 4.0%-6.0%. Compared with IF treatment, biochar treatments (IF+C and RIF+C) significantly increased rice grain yield by 9.9%-11.9%. There was no significant difference in rice grain yield between IF+C and RIF+C. Compared with IF treatment, IF+C and RIF+C treatment significantly increased nitrogen use efficiency by 7.7%-8.1%. Nitrogen partial productivity under RIF+C was increased by 57.1% and 52.3% in two years, respectively. 【Conclusion】The treatment of biochar + 30% reduction of inorganic nitrogen was a sustainable agronomic measure to effectively reduce N2O emission and to increase rice yield and nitrogen use efficiency in rice fields. However, the mitigating effect of biochar on greenhouse gas emission from rice fields should be further studied.

Key words: biochar, CH4, N2O, global warming potential, nitrogen use efficiency, rice yield