Jiangsu Co-innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, 210037, Nanjing, PR China.
School of Architecture, Southeast University, 210096, Nanjing, PR China.
NPJ Biofilms Microbiomes. 2023 Sep 23;9(1):69. doi: 10.1038/s41522-023-00438-9.
Artificial lights can cause critical microbial biodeterioration of heritage monuments by promoting the outbreak of phototrophic microbiomes when they are used for touristic viewing. Here, with the ultimate aim of providing innovative solutions for the conservation and visiting of such monuments, we conducted a pioneering two-year in situ manipulative experiment to evaluate the impacts of different artificial light wavelengths (i.e., blue, green and red lights compared to white light) on the phototrophic microbiome of a millennial Chinese imperial mausoleum. Our results show that artificial light can shape the ecophysiological features of the phototrophic bacteriome in this monument and reduce its potential for further biodeterioration. In general, Cyanobacteria dominated (42.0% of the total relative abundance) the phototrophic bacteriome of this cultural relic; however, they were also very sensitive to the choice of artificial light. Compared to white light, monochromatic light, especially green light, reduced Cyanobacteria abundances (18.6%) by decreasing photosynthetic pigment abundances (42.9%); decreased the abundances of heterotrophic species belonging to Proteobacteria (4.5%) and the proportion of genes (6.1%) associated with carbon (i.e., carbon fixation), nitrogen (i.e., denitrification), and sulfur (i.e., dissimilatory sulfate reduction) cycling; and further decreased organic acid (10.1-14.1%) production of the phototrophic bacteriome, which is known to be involved in biodeterioration. Taken together, our findings constitute a major advancement in understanding how light wavelengths influence the phototrophic microbiome in cultural relics, and we found that artificial lights with certain wavelengths (e.g., green light) can help long-term conservation while allowing tourism activities.
人工灯光在用于旅游观赏时，会促进光养微生物组的爆发，从而对文物古迹造成严重的微生物生物降解。在这里，我们进行了一项开创性的为期两年的现场操纵实验，以评估不同人工光波长（即蓝色、绿色和红色光与白光相比）对千年中国皇家陵墓光养微生物组的影响，以期为这些古迹的保护和参观提供创新的解决方案。我们的研究结果表明，人工光可以改变该纪念碑中光养细菌组的生理生态特征，并降低其进一步生物降解的潜力。总的来说，蓝细菌（占总相对丰度的 42.0%）是该文化遗产光养细菌组的优势菌群；然而，它们对人工光的选择也非常敏感。与白光相比，单色光，尤其是绿光，通过降低光合色素的丰度（42.9%），减少了蓝细菌的丰度（18.6%）；减少了属于变形菌门的异养物种的丰度（4.5%）和与碳（即固碳）、氮（即反硝化）和硫（即异化硫酸盐还原）循环相关的基因的比例（分别为 6.1%）；进一步减少了光养细菌组有机酸（10.1-14.1%）的产生，而有机酸已知会参与生物降解。总之，我们的研究结果在理解波长如何影响文物古迹中的光养微生物组方面取得了重大进展，我们发现某些波长的人工光（例如绿光）可以在允许旅游活动的同时，有助于长期保护。
