产甲烷微生物-埋地金属管道界面电子传递过程及对零价铁腐蚀的影响机制

埋地金属Fe(0)管道的微生物腐蚀已经严重影响我国石油、天然气资源的优化分配和输送，土壤重要种群产甲烷微生物是导致埋地金属管道腐蚀的关键因子。然而腐蚀过程的核心——产甲烷微生物-金属Fe(0)界面的胞外电子传递过程一直没有得到清晰的阐述。本项目拟构建产甲烷微生物与Fe(0)的反应体系，探究不同营养类型产甲烷微生物-Fe(0)电子传递过程以及直接电子传递的可能性和影响因素；分析产甲烷微生物与不同类型耗氢微生物共培养体系在Fe(0)腐蚀过程中互营或竞争的电子传递关系；弄清土壤埋地金属Fe(0)管道腐蚀表面生物膜表面形态、空间结构、主要活性组分及功能种群分布；明确导电矿物、生物膜中活性组分在产甲烷微生物-Fe(0)界面直接电子传递过程中的介导机制；力求在纯培养、共培养和群落不同层次阐明产甲烷微生物-金属Fe(0)界面的电子传递模式和影响机制，为土壤埋地金属管道的腐蚀防控提供重要科学依据。

The microbiologically influenced corrosion (MIC) of buried metallic Fe (0) pipelines has seriously affected the distribution and transportation of oil and natural gas resources in China. The important population of soil——methanogenic microorganism is the key factor of buried metallic pipeline corrosion. However, the core of corrosion process, the extracellular electron transfer process at the interface of methanogenic microorganism and metallic Fe (0) has not been clearly described. Therefore, this project plans to build a reaction system between methanogenic microorganism and metallic Fe (0). The electron transfer process of different trophic types of methanogenic microorganism with metallic Fe(0) will be explored. More important, the possibility of direct electron transfer and its influencing factors will be elucidated. The syntrophic or competitive interactions of co-cultures between methanogenic microorganism and hydrogenotrophic microorganism (acetic acid producing microorganism, iron/sulfur/sulfate reducing microorganism) in the process of metallic Fe (0) corrosion will be clarified. In addition, the surface morphology, spatial structure, main active components and microbial functional composition of biofilm on the surface of Fe (0) corrosion of buried soil pipeline will be analyzed. The mechanism of direct electron transfer mediated by active components of biofilm and conductive minerals will be explored during the process of Fe (0) corrosion by methanogenic microorganism. Finally, the different electron transfer mode of methanogenic microorganism and metallic Fe (0) will be provided at different levels of pure culture, co-cultures and soil microbial community. The results will offer new insights into the mechanisms of methanogenic microorganism and metallic Fe (0) corrosion and also provide an important scientific basis for the corrosion prevention and control of buried metallic pipelines in soil.