Analysis of Microbial Communities and Microbial Preservation of the Qilin Screen Wall and Text Brick Wall in the Jinshanling Great Wall

The Jinshanling Great Wall is an important part of the Ming Great Wall, the most important material cultural heritage of China, and is currently facing a significant threat of microbial degradation due to the widespread biological weathering of open-air masonry buildings. This study focuses on the Qilin Screen Wall and Text Brick Wall of the Jinshanling Great Wall, utilizing scanning electron microscopy (SEM) and metabarcoding analyses to reveal the diverse microbial communities coexisting on the masonry surfaces, including various lichens, molds, and bacteria. Twelve fungal strains were successfully isolated. The antimicrobial experiment results indicated that 0.6% isothiazolinone-based antimicrobial BC01, 50 mg/mL carvacrol and 50 mg/mL thymol exhibited a certain degree of antimicrobial activity against these strains. Overall, this study has laid a solid foundation for microbial control of the masonry Great Wall through in-depth analysis of microbial community structure and screening of highly effective antimicrobials.