不同氮素管理模式对黄土旱塬春玉米产量及N_(2)O排放的影响  

Effects of Different Nitrogen Application Patterns on Yield and Nitrous Oxide Emission of Spring Maize in Dryland Farming of the Loess Plateau

作　　者：鲁科丹 路远 王蕊 党廷辉[1,5] LU KeDan;LU Yuan;WANG Rui;DANG TingHui(The Research Center of Soil and Water Conservation and Ecological Environment,Chinese Academy of Sciences and Ministry of Education,Yangling 712100,Shaanxi;Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources,Yangling 712100,Shaanxi;University of Chinese Academy of Sciences,Beijing 100049;College of Natural Resources and Environment,Northwest A&F University,Yangling 712100,Shaanxi;Institute of Soil and Water Conservation,Northwest A&F University,Yangling 712100,Shaanxi)

机构地区：[1]中国科学院教育部水土保持与生态环境研究中心,陕西杨凌712100 [2]中国科学院水利部水土保持研究所,陕西杨凌712100 [3]中国科学院大学,北京100049 [4]西北农林科技大学资源环境学院,陕西杨凌712100 [5]西北农林科技大学水土保持研究所,陕西杨凌712100

出　　处：《中国农业科学》2024年第18期3642-3653,共12页Scientia Agricultura Sinica

基　　金：国家自然科学基金重点项目(41830751)。

摘　　要：【目的】探讨不同氮素管理模式对玉米产量、N_(2)O排放的影响,为黄土旱塬区合理施用氮肥和减缓温室气体排放提供理论依据。【方法】依托中国科学院长武黄土高原农业生态试验站,以春玉米先玉335为研究对象,开展为期2年的田间定位试验。试验共设置5种不同氮素管理模式:不施氮(no fertilizer)、传统施氮(Con,250 kg N·hm^(-2))、减量施氮(Opt,200 kg N·hm^(-2))、减量施氮+缓控释肥(Opt+SR,200 kg N·hm^(-2))、减量施氮+硝化抑制剂(Opt+DCD,200 kg N·hm^(-2))。用静态箱-气相色谱法监测N_(2)O排放通量,并计算全球增温潜势和N_(2)O气体排放强度,分析不同氮素管理模式对春玉米产量和N_(2)O排放的影响。【结果】(1)氮肥施用后N_(2)O排放迅速升高,在施肥后2 d左右达到峰值,维持10 d后快速下降。减量施氮模式显著降低N_(2)O排放量(P<0.05)。与Con处理相比,Opt、Opt+DCD和Opt+SR处理N_(2)O排放量降低幅度分别为21.4%、27.6%和26.0%。Con、Opt、Opt+DCD和Opt+SR处理的N_(2)O增温潜势依次为425.01、334.01、307.83、314.57 kg CO_(2)-eq·hm^(-2)。与Con处理相比,Opt+DCD显著降低了N_(2)O排放强度,降幅为30.1%(P<0.05)。(2)N_(2)O排放量与表层土壤NH4+-N含量呈极显著正相关(P<0.01),而与土壤水分、温度无明显相关性。(3)与Con处理相比,Opt、Opt+DCD和Opt+SR处理能显著提高氮肥农学效率(增幅依次为25.5%、25.7%、22.2%)及氮肥偏生产力(增幅依次为29.9%、28.7%、25.4%)(P<0.05),但对春玉米的产量无显著影响。【结论】在黄土旱塬地区,适当减量施氮、缓控释肥及添加硝化抑制剂均能取得N_(2)O减排和玉米增产的效果,其中减氮20%并添加硝化抑制剂在保证玉米产量的同时,N_(2)O减排效果最好。【Objective】Investigating the impacts of different N application regimes on crop(spring maize)yield and nitrous oxide(N_(2)O)emission provided the basis for reasonable N(Nitrogen)application and GHG(Greenhouse Gas)emission mitigation in dryland farming of the Loess Plateau.【Method】In this study,the impacts of five N application regimes on spring maize(Xianyu 335)yield and N_(2)O emission were investigated in a short-term(2 years)experiment in Changwu Agro-Ecological Experimental Station,and the treatments included:no fertilizer;conventional N fertilization(Con,250 kg N⋅hm^(-2));optimized N fertilization(Opt,200 kg N⋅hm^(-2));optimized N fertilization with slow-release fertilizer(Opt+SR,200 kg N⋅hm^(-2));optimized N fertilization with dicyandiamide(Opt+DCD,200 kg N⋅hm^(-2)).The N_(2)O emission fluxes were monitored using sealed static chambers,and the gas chromatograph and the global warming potential(GWP)was calculated.【Result】(1)N_(2)O emissions increased rapidly after N application,reaching a peak on the second day,and rapidly decreased after 10 days of maintenance.Optimized N fertilization significantly decreased N_(2)O emissions(P<0.05).Compared with Con,the reductions in N_(2)O emissions under Opt,Opt+DCD,and Opt+SR were 21.4%,27.6%,and 26.0%,respectively.The GWP of N_(2)O emissions under Con,Opt,Opt+DCD,and Opt+SR were 425.01,334.01,307.83,and 314.57 kgCO_(2)-eq⋅hm^(-2),respectively.Opt+DCD significantly reduced N_(2)O emission intensity by 27.8%than that under Con(P<0.05).(2)N_(2)O emissions were highly correlated with surface soil NH4+-N content(P<0.01),but showed no significant correlation with soil moisture and temperature.(3)Compared with Con,Opt,Opt+DCD,and Opt+SR significantly improved N fertilizer agronomic efficiency(with increases of 25.5%,25.7%,and 22.2%,respectively)and nitrogen fertilizer partial factor productivity(with increases of 29.9%,28.7%,and 25.4%,respectively)(P<0.05),whereas they had no significant impact on spring maize yield.【Conclusion】In dryland farming of

关 键 词：减量施氮 缓控释肥 硝化抑制剂 春玉米 产量 N_(2)O排放 黄土旱塬 

分 类 号：S513[农业科学—作物学]