摘要
为探究氮肥和秸秆还田方式对N2O排放的影响,本研究在关中地区冬小麦-夏玉米轮作模式下,采用双因素裂区设计,主区为常规施氮(G)和减量施氮(70%G);副区为秸秆不还田(N)、秸秆还田(S)和秸秆还田+生物炭(SB),分析对N2O排放和产量的影响及与相关影响因子间的关系.结果表明,小麦季和玉米季各处理在施肥后第5~16d内相继出现N2O排放高峰,在降雨后也出现N2O排放峰值.N2O通量和土壤温度、NH4+-N含量呈显著正相关.在同等施氮水平下,S处理增加了N2O排放量,SB处理可降低N2O排放量,S和SB处理均能显著增加作物产量,且SB增产幅度更大;70%G水平的N2O年排放量较G水平减少了40%~48%,而产量并没有明显减少.综合考虑,在常规施氮基础上减氮30%配合秸秆+生物炭,在保证作物高产的同时,N2O减排效果最好.
In order to explore the impacts of nitrogen fertilizer and straw returning methods on N2O emissions,a two-factor split-zone design was adopted for experimentation under the winter wheat-summer maize rotation model in the Guanzhong area of Shanxi,China.The main areas of interest were conventional nitrogen(G)and reduced nitrogen(70%G);the sub-areas were straw no return(N),straw return(S),and straw return+biochar(SB);we analyzed their impacts on N2O emissions and crop yield,and the relationships with related impact factors.The results showed that the N2O emissions peaks appeared in the wheat season and maize season treatments within 5-16 days after fertilization,and also appeared after rainfall.The N2O flux was significantly and positively correlated with soil temperature and NH4+-N content.Regardless of the wheat season,maize season,or annual total N2O emissions,the 70%GSB treatment was the lowest and the GS treatment was the highest.At the same level of nitrogen application,S treatment increased N2O emissions,SB treatment could reduce N2O emissions,both S and SB treatments could significantly increase crop yields,and SB production increased more;70%G-level annual N2O emissions,when compared with the G level,had been reduced by 40%to 48%,while the yield has not decreased significantly.Through comprehensive consideration,a reduction of nitrogen by 30%was achieved through the combination of straw+biochar on the basis of conventional nitrogen application,while ensuring high crop yields and the best N2O emissions reduction.
作者
许宏伟
李娜
冯永忠
任广鑫
谢呈辉
吕宏菲
马星霞
郝嘉琪
XU Hong-wei;LI Na;FENG Yong-zhong;REN Guang-xin;XIE Cheng-hui;LüHong-fei;MA Xing-xia;HAO Jia-qi(College of Agronomy,Northwest A&F University,Yangling 712100,China;Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province,Yangling 712100,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2020年第12期5668-5676,共9页
Environmental Science
基金
国家自然科学基金项目(31971859)。
关键词
氮肥
秸秆还田
生物炭
N2O排放
产量
nitrogen fertilizer
residues
biochar
N2O emissions
yield
