Environmental vulnerability assessment for mainland China based on entropy method

Evaluation of environmental vulnerability over large areas is a difficult and complex process because it is affected by many variables. Few research on environmental vulnerability assessment is conducted in mainland China comprehensively. In this study, indicators were selected mainly from the function of ecosystem factors and the natural environmental factors associated with the life of the residents. After collinearity diagnostics, 12 indicators remained, covering landform, meteorology, vegetation and irrigation conditions. Entropy method was used to determine the weights for indicators. Results indicate that the vulnerability degree in western China is significant higher than that of eastern China. The spatial distributions of vulnerability gradation are analyzed at national, regional and provincial scales, respectively. On the whole, areas of light vulnerability are main in the northeastern region. Potential, light and medium vulnerability occupy the largest area in the eastern and central region. Percentages of medium, heavy and very heavy vulnerability are the maximum in the western region. The change trend of vulnerability gradation showed that eco-environment has got more vulnerable since 2000. The evaluation results would provide references for the environmental protection and the formulation of related policies.