Spatial-temporal distribution characteristics and influencing factors of the grottoes in Gansu Province

The research on spatial and temporal distribution is a necessary prerequisite and important basis for the spatial integration and protection of historical and cultural heritage. Taking 166 grottoes in Gansu Province as an example, the spatial and temporal distribution characteristics and influencing factors of grottoes were analyzed by GIS spatial analysis technology. The results show that: ① The open niche statues in grottoes show an evolutionary trend of increasing first and then decreasing and then increasing, with the peak periods of open niche statues in Wei, Jin, Southern and Northern Dynasties, Sui, Tang and Five dynasties. ② A belt-shaped high-density area with Tianshui and Pingliang as the core has been formed in eastern Gansu. From the Wei, Jin, Southern and Northern Dynasties to the Ming and Qing Dynasties, the high density area of new grottoes was Tianshui, Jiuquan and Zhangye. ③ The spatial distribution of grottoes shifted significantly in different periods, and the distribution center of grottoes shifted from the southeast to the northwest and then continued to the southeast. ④ The spatial and temporal distribution of grottoes is mainly affected by topography, river system, stratum lithology, political economy, buddhism development, road traffic and other factors. This has important reference significance for the integrated protection, value inheritance and sustainable utilization of the grottoes in Gansu Province.