Spatiotemporal characteristics of cultural sites and their driving forces in the Ili River Valley during historical periods

This study applies ArcGIS to analyze the spatiotemporal distribution of cultural sites in the Ili River Valley in northwestern China. It explores relationships between the sites’ spatiotemporal evolutionary characteristics, human history, and the natural environment. The results indicate that the numbers and proportions of the sites, and the frequency of their occurrence, exhibited an inverted V-shaped change trend during six historical periods. The “high in the east and low in the west” spatial distribution pattern of the first three periods shifted to the one the “high in the west and low in the east” during the latter three periods, demonstrating a change in the spatial center of gravity of human activities. The sites were mainly distributed on slopes of grades 1–5, with their proportions increasing from 75% during the Spring and Autumn Period (770 BC–476 BC)–Qin Dynasty (221 BC–207 BC) to 93.75% during the Qing Dynasty–Modern period. The concentrated distribution of site elevations shifted from grades 4–8 during the Spring and Autumn Period–Qin Dynasty, and the Western Han (206 BC–8)–Southern and Northern Dynasties (420–589), to grades 1–4 during the latter three periods. The number of sites showed a shifting trend from high-elevation mountains and hills to low-elevation plains, and from high slopes to low slopes. In particular, the sites exhibited a special “moist” evolutionary pattern of migration from middle and upstream areas to downstream areas, as opposed to the migration pattern of sites located in typical arid areas. The study also considered factors influencing the distribution and spatiotemporal evolution of cultural sites, notably, human factors and natural factors.