The ecology of microbiome on cultural relics: The linkage of assembly, composition and biodeterioration

The process of microbial deterioration leads to irreversible damage to cultural relics, weakening their capacity for preserving human civilization. Previous studies have focused primarily on descriptions of the composition, diversity, and metabolisms of microbial communities associated with relics. However, owing to the influence of community assembly on composition and ecological functions and to formulate preservation strategies for relics, it is imperative to understand the assembly of microbial communities and their emergent ecological functions. In this respect, this study uses ecological niche theory and neutral process theory to delineate the interactions among the assembly processes, species composition, and ecological functions of microbial communities within Qinling Mausoleum (one of the two mausoleums of the Southern Tang Dynasty). Our results indicate that deterministic processes reduce the diversity of bacterial communities, thereby enhancing the multifunctionality and metabolic activity related to biodeterioration. The bacterial community in the middle of the mausoleum was dominated by deterministic processes, and amino acid metabolism, carbohydrate metabolism and lipid metabolism were elevated. Thus, the middle community was more likely to produce organic and inorganic acids that eroded the brick. In this context, deterministic processes increase the potential risk of biodeterioration of the brick in the Qinling Mausoleum. This highly interactive cascade underscores the role of microbial community assembly in predicting the intensity of biodeterioration within mausoleum environments.