中文摘要：

水稻田是温室气体甲烷（CH4）的重要释放源之一，有机质在水稻土中通过厌氧分解途径最终产生CH4和CO2。短链脂肪酸互营氧化是水稻土有机质降解的关键环节，但是由于互营微生物独特的生理生态特性，目前人们对于参与该过程的微生物群落及功能了解甚少。稳定同位素探针（SIP）技术被认为是实现环境中参与物质转化微生物种类与功能相耦合的有力工具。本文首先讨论互营过程的热力学基础和互营微生物的种间相互作用模式，然后简要讨论了互营过程的环境影响因子，最后详细综述稳定同位素探针技术在水稻土短链脂肪酸互营氧化过程中的相关研究。目前的研究表明：参与水稻土脂肪酸互营氧化过程的互营细菌种类丰富、多样性高；除已知互营细菌的作用外，大量未培养、功能未知的细菌类型也可能参与短链脂肪酸的互营氧化：对于互营细菌的伙伴而言，新型产甲烷胞菌属（Methanocella）类型的古菌在不同脂肪酸互营降解过程中均起主要作用。揭示了这类产甲烷古茵在水稻土厌氧产甲烷过程中的重要作用。

英文摘要：

Flooded rice field is one of major biogenic sources of greenhouse gas CH4. Com- plex organic matter is degraded to CH4 and CO2 by the co-operation of anaerobic microorganisms of several metabolic guilds involving the syntrophic oxidation of short-chain fatty acids like propionate, butyrate and acetate. Due to the fastidious nature of cultivation, the diversity and ecology of microorganisms involved in syntrophic oxidation in natural environments like paddy soils remain largely unexplored. Stable isotope probing （SIP）, which links microbial identity and function, is a powerful tool to investigate the syntrophic oxidation of fatty acids in flooded paddy soils. This article reviews the recent research progresses in the thermodynamic principles, the interspecies interactions in the syntrophic oxidation of fatty acids, and paddy soils employing SIP technology. The knowledge acquired suggests that phylogenetically diverse bacterial groups are active in the syntrophic oxidation： except classic syntrophic bacte- ria, organisms belonging to uncultivated phylogenetic groups are also detected, which can serve as candidate syntrophs. Among archaea, Methanocella is the major methanogen partner in syntrophic oxidation of different fatty acids, indicating the importance of this group in CH4 production of paddy field soil.