中文摘要：

基于PSR（压力—状态—响应）模型,构建兰州市生态安全评价指标体系,利用变异系数法确定指标权重,加权求出兰州市2007—2012年的生态安全指数值,并分析其生态安全发展趋势。兰州市生态安全动态评判结果为：2007年为恶化的不安全系统,2008年、2009年、2011年为可改善的不安全系统,2010年为不安全系统,2012年为安全系统,表明兰州市整体环境在逐步改善,但由于生态基础薄弱、人口对资源压力较大,兰州市整体生态安全状况不容乐观。针对兰州市生态环境现状问题提出了改善措施。

英文摘要：

On the basis of the PSR model,each security index of Lanzhou City from 2007 to 2012 and its weight in urban ecosystem were calculated,and evaluated the urban ecological security trend of Lanzhou City. The result showed that the eco-security dynamic assessment of Lanzhou City was very insecurity in 2007,improved insecurity in 2008,2009 and 2011,insecurity in 2010,security in 2012,which indicated the ecological environment of Lanzhou City was improved. Due to weak ecological foundation of Lanzhou City and the great pressure on resources of population,the whole ecological security of Lanzhou City was not optimistic. At last,this paper put forward the improvement measures according to the current eco-security condition of Lanzhou City.