Spatial Fairness and Changes in Transport Infrastructure in the Qinghai-Tibet Plateau Area from 1976 to 2016

Abstract
The Qinghai-Tibet Plateau area (QTP) is the most unique environmental-population region and an important natural laboratory for the study of human-land relations. The poor transportation conditions have long restricted socio-economic development. The research on the transport infrastructure and spatial effect in the QTP is of significance to the sustainable development of the region. Accordingly, a spatial accessibility model was used to analyze the spatial pattern of accessibility in QTP from 1976–2016, examine the accessibility evolution trend on the township scale and reveal the spatial fairness and changes in accessibility. The main conclusions are as follows: (1) The accessibility to major cities improved and the time-space convergence effect was significant. (2) The spatial autocorrelation analysis results showed that the improvement in transport infrastructure had a significant impact on the agglomeration of the accessibility level. (3) Access time from towns to the nearest major city are much shorter. More Tibetan people have more opportunities to access cities. (4) The accessibility coefficient and relative accessibility revealed distributive effects and spatial fairness of accessibility. (5) The global coefficient of variation value demonstrated an increasing trend, which indicates that spatial unfairness of transport is increasing.