Abstract Two sets of twelve Portland limestone tablets were attached to carousels outside and under the open, lightweight shelter at Bishop’s Palace (Witney, England) for 18 months to assess the influence of shelters on soiling and microbiological growth on stone. At the start, and at 6-month intervals, tablets were analysed using microscopy (optical and SEM), colour measurement (spectrophotometry), weight change measurement and salt content determination (ion chromatography). Concentrations of NO2 and SO2 were also monitored for a month using diffusion tubes. In addition, results were compared with those obtained by the UK National Materials Exposure Programme (NMEP) on chemical weathering rates. Differences in soiling and biological growth on sheltered and unsheltered samples, and their influence on limestone decay were established. The shelter is likely to reduce biological growth by modifying the micro-environmental conditions. However, it may also exacerbate dust deposition, which might increase decay rates in the long-term.

中文翻译：

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对英格兰威特尼主教宫考古现场开放式住房在减少污染和微生物生长中的作用的评估

摘要在Bishop's Palace（英格兰威特尼）的轻巧开放式庇护所的外部和下方，将两套12片波特兰石灰石片附着在旋转木马上，进行了18个月的评估，以评估庇护所对石块的污染和微生物生长的影响。在开始时和间隔6个月时，使用显微镜（光学和SEM），颜色测量（分光光度法），重量变化测量和盐含量测定（离子色谱法）分析片剂。还使用扩散管监测了一个月的NO2和SO2浓度。此外，将结果与英国国家材料暴露计划（NMEP）获得的化学风化率进行了比较。确定了庇护和非庇护性样品在土壤和生物生长方面的差异，以及它们对石灰石腐烂的影响。庇护所可能会通过修改微环境条件来减少生物生长。但是，它也可能加剧粉尘沉积，从长远来看可能会增加衰减率。