Microenvironmental Features of Cave 133 in the Maiji Mountain Grottoes, Tianshui

The temperature and humidity changes of the micro-environment in caves are the main factors affecting the preservation of cultural relics in grottoes. Cave 133 is a specific embodiment of the outstanding universal value of Maiji Mountain Grottoes. To better understand the impact of external environment on the micro-environment of caves, this study conducted a comparative analysis of the external environment of Maiji Mountain Grottoes, the characteristics of micro-environmental changes in caves and their correlation. The results show that the temperature of the external atmosphere of Maiji Mountain changes seasonally, and the relative humidity is significantly affected by rainfall. The temperature and humidity changes of Cave 133 are jointly affected by the external environment, the mountain where the grotto is located, and the shape of the cave. The phenomenon of condensation water promotes the weathering of sandstone cultural relics. It is necessary to open the cave door to accelerate air circulation in the cave, especially after summer precipitation. The regular changes of the micro-environment in caves revealed in this study provide a scientific basis for the preventive protection of Cave 133.