Abstract: Based on the statistical data of Changsha city from 2007 to 2016, 20 indicators were selected to construct the evaluation system of ecological security in Changsha from three aspects, including the pressure of ecological security, the status of urban expansion and economic development, and the social and ecological response. The main factors affecting ecological security were analyzed from the angle of correlation degree and contribution degree. The results showed that, in the last ten years, the ecological safety value of Changsha city fluctuated year by year and showed a trend of improvement as a whole. There were some indexes with high correlation with ecological security, such as per capita GDP, urbanization level, harmless disposal capacity of domestic waste, etc. Although there were differences in the main contribution indexes affecting ecological security in each year, they were mainly concentrated the per capita urban green space area and industrial dust removal, etc. Therefore, some countermeasures and suggestions were put forward, such as attaching importance to green land construction and pollution control, improving resource utilization efficiency, people-oriented, and enhancing the participation of residents in the protection of ecological security.

Key words: ecological security, urban land expansion, grey relational analysis, contribution analysis, Changsha city