不同灌溉模式和施氮处理下稻田CH_4和N_2O排放  

Emissions of CH_4 and N_2O under different irrigation methods and nitrogen treatments

作　　者：董艳芳[1] 黄景[1] 李伏生[1] 王楷[1] 方泽涛 刘靖雯[1] 黄忠华 罗维钢 

机构地区：[1]广西大学农学院/广西喀斯特地区节水农业新技术院士工作站/广西高校作物栽培学与耕作学重点实验室,南宁530005 [2]南宁市灌溉试验站,南宁530001

出　　处：《植物营养与肥料学报》2017年第3期578-588,共11页Journal of Plant Nutrition and Fertilizers

基　　金：国家自然科学基金(51469003)资助

摘　　要：【目的】研究不同灌溉模式和施氮处理稻田CH_4和N_2O的排放规律、综合增温潜势和综合排放强度,以期获得降低稻田CH_4和N_2O排放的灌溉模式和施氮管理。【方法】2015~2016年在广西南宁市灌溉试验站进行晚稻和早稻大田试验,两次试验均设3种灌溉模式:常规灌溉(CIR)、"薄浅湿晒"灌溉(TIR)和干湿交替灌溉(DIR)。2种尿素-N和猪粪-N比例:100%尿素-N(FM1),50%尿素-N+50%猪粪-N(FM2)。共设CIR-FM1、TIR-FM1、DIR-FM1、CIR-FM2、TIR-FM2和DIR-FM2 6个处理,用静态箱–气相色谱法测定了水稻生育期内稻田CH_4和N_2O排放通量,分析了早晚稻生育期内CH_4和N_2O累积排放量和综合增温潜势,并结合产量分析了CH_4和N_2O综合排放强度。【结果】DIR下FM2处理早稻产量和两季总产量比FM1处理分别提高18.8%和17.7%,FM2下TIR和DIR模式早稻产量分别比CIR模式提高20.9%和37.4%以及DIR模式两季总产量比CIR模式提高21.5%。不同处理早晚稻生育前期CH_4排放通量较高,生育中后期CH_4排放通量较低。水稻生育期内TIR和DIR模式CH_4累积排放量低于CIR模式,FM1处理CH_4累积排放量低于FM2处理。不同处理早晚稻生育前期N_2O的排放通量为负值或者较低,N_2O排放主要集中在晒田完成复水之后及成熟期稻田水分落干时,DIR模式N_2O累积排放量显著高于CIR模式,FM2处理N_2O累积排放量高于FM1处理。不同处理稻田CH_4和N_2O的排放彼此间存在消长关系。CH_4对综合增温潜势的贡献率达99%以上,而N_2O的贡献率不足1%。3种灌溉模式下FM1处理CH_4或N_2O增温潜势、CH_4和N_2O综合增温潜势和排放强度均低于FM2处理,2种施氮处理下TIR和DIR模式CH_4和N_2O综合增温潜势和排放强度低于CIR模式。【结论】与常规灌溉相比,"薄浅湿晒"灌溉水稻产量和N_2O排放有所提高,但是降低CH_4排放量及CH_4和N_2O综合增温潜势和排放强度;干湿交替灌溉增加水稻产量和N_2O排放,但是降低C[ Objectives ] The aim of this study was to investigate the emissions, global warming potential （GWP） and comprehensive emission intensity （CEI） of CH4 and N2O in paddy field under different irrigation methods and nitrogen treatments, so as to obtain irrigation method and nitrogen management for reducing CH4 and N2O emissions from paddy soil. [ Methods ] In 2015 and 2016, the field experiments of early rice and late rice were carried out in Nanning Irrigation Experimental Station. Two experiments had three irrigation methods, i.e.conventional irrigation （CIR）, ＂thin-shallow-wet-dry＂ irrigation （TIR） and alternative drying and wetting irrigation （DIR）, and two ratios ofurea-N to pig manure-N, i.e. 100% urea-N （FM） and 50% urea-N and 50% pig manure-N （FM2）. There were six treatments, i.e. CIR-FM1, TIR-FM1, DIR-FM1, CIR-FM2, TIR-FM2 and DIR- FM2. CH4 and N2O fluxes during the rice-growing seasons were collected using static closed chamber method and determined using a gas chromatography. Accumulative emission and GWP of CH, and N2O were analyzed and CEI of CH4 and N2O was the ratio of GWP of CH4 and N2O to rice yield. [ Results ] Compared to the FM1 treatment, FM2 treatment increases the early rice yield and total yields of late rice and early rice by 18.8% and 17.7% under DIR, respectively. Compared to CIR method, TIR and DIR methods increase the yield of early rice by 20.9% and 37.4%, respectively, and DIR method increases total yield of late rice and early rice by 21.5% under FM2. The CH4 emission fluxes of late and early rice seasons in different treatments are high at the early growth stage and low at the late growth stage. During the rice-growing period, TIR and DIR methods have lower accumulative CH4 emission from paddy field than CIR method, and FM1 treatment has significantly lower accumulative CH4 emission from paddy field than FM2 treatment. The N^O emission flux is negative or low at the early growth stage, and the N2O emission from paddy field is mainly concentrated in th

关 键 词：“薄浅湿晒”灌溉 干湿交替灌溉 猪粪 CH4和N2O综合增温潜势 综合排放强度 

分 类 号：S511[农业科学—作物学]