Analysis of the Three-level Gradient Distribution Characteristics of Tibetan Population in China Based on GIS

In this study, a county-level database of the Tibetan population of China was built using ArcGIS 10.3, by extracting information from the 3rd and 6th Chinese National Population Census. On this basis, the spatial pattern of the Tibetan population in China was analysed using spatial statistical analysis and exploratory analysis methods. The results demonstrate that over 90% of the Tibetan population is distributed west of the ‘Heihe-Tengchong Line’, while less than 10% of the Tibetan population is distributed east of the line. Further, with the ‘Heihe-Tengchong Line’ and the boundary line of TAR and other Tibetan areas as demarcation lines, there is a three-level gradient spatial pattern of the Tibetan population. Southwest of the ‘Heihe-Tengchong Line’ is the first gradient with the vast majority of the Tibetan population. The northwest of the ‘Heihe-Tengchong Line’ is the second gradient with a lower Tibetan population, and east of the ‘Heihe-Tengchong Line’ is the third gradient with an even lower Tibetan population. Historical and cultural factors have played a key role in the formation of this three-level gradient spatial pattern of the Tibetan population.