Spatiotemporal analysis of ecological vulnerability in the Tibet Autonomous Region based on a pressure-state-response-management framework

Abstract The Qinghai-Tibet Plateau is facing a crisis of ecological degradation against a background of global warming and the intensification of human activities. With the aim of evaluating the spatial and temporal distribution of ecological vulnerability, this study established a new comprehensive pressure-state-response-management (PSRM) model based on the differences in the relative importance of indicators in a vulnerability evaluation system in different regions. The factors influencing ecological vulnerability were determined by calculating the correlation coefficient between the ecological vulnerability index (EVI) and the potential impact factors. The results showed that the spatial distribution of EVI in the Tibet Autonomous Region varied significantly, gradually decreasing from southeast to northwest. The regional ecological environment gradually improved from 2000 to 2015 and the EVI score increased. Following the establishment of national nature reserves in 2005, the areas that were extremely vulnerable in 2000 (accounting for 53% of the total area) were transformed into severely vulnerable or moderately vulnerable areas. The proportion of non-vulnerable areas also increased from 3% in 2010 to 6% in 2015 as cities expanded. The correlation analysis among vectors showed that GDP, population density, the proportion of tertiary industry, education level and policy support were strongly correlated with the EVI. Human activity had a greater impact on the EVI in urban areas. Our study provides suggestions for more sustainable development pathways to reduce environmental pressure and protect the fragile ecological environment. The approach used here can provide technical support and references for the ecological assessment and restoration of other high-altitude zones in China or elsewhere in the world.