农业环境科学学报2017，Vol.36Issue(5)：1012-1020,9.DOI:10.11654/jaes.2016-1581
不同灌溉模式和施氮量条件下稻田甲烷排放及其与有机碳组分关系
Soil CH4 emission and its relationship with organic carbon fraction under different irrigation methods and ni-trogen rates
摘要
Abstract
The readily decomposed organic matter in the paddy ecosystem increase soil methane(CH4)emission under anaerobic environ-ment, while methane oxidizing bacteria(MOB)oxidation of methane reduces soil CH4 emission under better aeration environment. Field ex-periments with different irrigation methods and nitrogen(N)rates were carried out to measure the contents of organic carbon(SOC)and eas-ily oxidized organic carbon(LOC), microbial biomass carbon(MBC)and the number of MOB at different growth stages, and CH4 emission fluxes from paddy field during the growth stage, and then the relationships between the CH4 emission flux and the contents of SOC and LOC, MBC and MOB in soils at the sampling days were analyzed, so as to obtain the rational irrigation mode and N rate for CH4 reduction. Two-season field experiments included three irrigation methods, i.e. conventional irrigation(C),"thin-shallow-wet-dry"irrigation(T)and alter-nate drying and wetting irrigation(D), and two N rates(N1120 kg·hm-2 and N2150 kg·hm-2). Results show that D mode had lower SOC content at the booting stage of late rice and tillering stage of early rice under N1, and D mode had the highest SOC content at the four growth stages of early rice and late rice under N2. When planting early rice and late rice, D mode had lower LOC content, and C mode had lower MOB and higher MBC. The contents of SOC, LOC, MBC and MOB in N2 were higher than those of N1. Accumulative CH4 emissions over the whole growth stage of early rice or late rice and the total of both seasons in D mode were significantly lower than those of T and C modes, but these indices in N2 were higher than those of N1. CH4 emission flux was directly influenced by the soil MOB, LOC and MBC and indirectly affected by the SOC. CH4 emission from paddy soil was the lowest under alternate drying and wetting irrigation and N rate of 120 kg·hm-2.关键词
甲烷排放/"薄浅湿晒"灌溉/干湿交替灌溉/施氮量Key words
CH4 emission/"Thin-shallow-wet-dry"irrigation/alternate drying and wetting irrigation/nitrogen rate分类
资源环境引用本文复制引用
王楷,李伏生,方泽涛,董艳芳,刘靖雯,黄忠华,罗维钢..不同灌溉模式和施氮量条件下稻田甲烷排放及其与有机碳组分关系[J].农业环境科学学报,2017,36(5):1012-1020,9.基金项目
国家自然科学基金项目(51469003) （51469003）
The National Natural Science Foundation of China(51469003) The National Natural Science Foundation of China(51469003) （51469003）
