色变是古代壁画劣化的常见现象，严重影响到壁画品质与美学价值。对壁画色变机理的研究主要集中在物理化学方面，尽管有研究表明微生物介导了壁画色变过程，但微生物导致壁画色变机理研究少有报道，壁画色变的微生物学机制尚不清楚。本项目针对丝绸之路甘肃段不同降水梯度下敦煌莫高窟（35mm/年）、武威天梯山石窟（296mm/年）和天水麦积山石窟（960mm/年）典型洞窟壁画的色变程度，运用宏基因组高通量测序技术，研究不同石窟色变壁画中微生物群落结构特征，比较不同降雨条件下壁画色变程度及微生物组成差异；运用典型对应分析及非度量多维尺度分析等方法，解析导致壁画色变的主因子及其贡献率；通过仿真模拟实验研究优势微生物与色变颜料退化进程间耦合关系，揭示微生物介导的壁画色变机理，为色变壁画的科学保护提供技术支撑。研究成果对同类文化遗产的保护具有重要的示范价值，对提升我国文化遗产保护水平的国际化程度具有重要的现实意义。

Color change of ancient wall paintings is a universal phenomenon which has serious effects to the quality and aesthetic value of wall paintings preserved in The Silk Road Grottoes, Gansu. Most of the early study toward to the mechanisms of mural color change mainly focused on the physical and chemical aspects, although a few of studies showed that microorganisms have took part in and mediated the color change process of ancient wall paintings, little of reports referred microbial biodeterioration and biodegradation mechanisms of mural's color change progress. This project aimed at murals preserved in three different grottoes with different extent of color changing and in varied precipitation of The Silk Road grottoes, Mogao Grottoes (35mm/year), Wuwei Tiantishan grottoes (296mm/year) and Tianshui maijishan grottoes (960mm/year), The Metagenomic high-throughput sequencing techniques will be used for the study of microbial community structures in different grottoes, The statistical methods such as Canonical Correspondence Analysis(CCA) and Nonmetric Multi-dimensional Scaling(NMDS) will be used to find out the major factors and their contribution rate in the color change process of wall paintings. After simulated experiments, combined with the study of coupling relationship between dominant microorganisms and mineral pigments deterioration, it is possible to reveal microbial mediated biodeterioration of wall paintings; These results can provide technological support for the conservation of color changed murals. Findings of this project has significant demonstration values for the conservation of the similar cultural relics, and with some important practical significance for the prompt of cultural heritage protection internationalization degree in China.