目的 分析华南一成品油管道内微生物腐蚀（MIC）的主要原因及行为，为成品油管道安全运行提供支撑。方法 利用微生物分析、表面分析和电化学手段，分析成品油管道沉积物中可能引发腐蚀的细菌群落，研究细菌群落协同作用下，X65管线钢的腐蚀状态，并对X65管线钢在成品油管道沉积物稀释液中的MIC行为进行分析。结果 从属水平来看，成品油管道沉积物中相对丰度大于0.1%的29种菌属中有13种可能引发MIC。在实验的1~3天，天然稀释液体系（X65-Bacteria）的OCP持续正移，且正移幅度大于灭菌稀释液体系（X65-Asepsis），第3天的EIS阻抗弧半径最大。在实验的3~7天，天然稀释液（X65-Bacterias）体系的OCP负移，且负移程度明显大于灭菌稀释液（X65-Asepsis）体系。在实验的第7天，天然稀释液（X65-Bacterias）体系的阻抗弧半径小于灭菌稀释液（X65-Asepsis）体系，且自腐蚀电位更负。对生成的生物膜进行成分分析发现，生物膜和腐蚀产物膜主要由有机物和铁的氧化物组成。结论 柠檬酸杆菌属（Citrobacter）和鞘氨醇单胞菌属（Sphingomonas）可能是造成华南一成品油管道沉积物中MIC的主要菌群。在管道沉积物中细菌群落的协同作用下，X65管线钢的腐蚀速度加快。

The work aims to analyze the main causes and behaviors of microbiologically influenced corrosion (MIC) in oil product pipeline in South China to provide support for the safe operation of the oil product pipeline. Microbiological analysis methods, surface analysis technology and electrochemical methods were used to analyze the bacterial communities that might cause corrosion in the sediments of oil product pipeline, and to study the corrosion status of X65 pipeline steel and investigate the MIC behavior of X65 pipeline steel in diluent of product oil pipeline sediment. From the perspective of genus level, 13 of 29 species of genus with relative abundance greater than 0.1% in the oil product pipeline sediments might trigger MIC. During the first 1~3 days of the experiment, the OCP of the X65-Bacterial system continued to move forward with a larger range than that of the X65-Asepsis system, and the EIS had the largest impedance arc radius on the third day. In the 3~7 days of the experiment, the negative shift of OCP in X65-Bacterias system was significantly greater than that of X65-Asepsis system. On the 7th day of the experiment, the impedance arc radius of the X65-Bacterias system was smaller than that of the X65-Asepsis system, and the self-corrosion potential was more negative. Composition analysis was carried out to the generated biofilm and corrosion product film, which were mainly composed of organic matter and iron oxides. Citrobacter and Sphingomonas may be the main bacterial colonies causing MIC in the sediment of a product pipeline in South China. With the synergistic effect of bacterial communities in pipeline sediments, the corrosion rate of X65 pipeline steel is accelerated.