基于PSR模型的兰州市土地生态安全时空差异评价

研究了兰州市2006~2013年土地生态安全的时空差异。主要依据PSR模型建立评价指标体系,运用熵权法与综合评价法对不同时期兰州市及各县区土地生态安全状况进行分析。结果表明:(1)兰州市土地生态安全由2006年的"恶劣"状态转变为2013年的"良好"状态;(2)土地生态压力指数从0.176下降为0.145,土地生态状态与土地生态响应指数分别从0.063、0.160提升到0.295、0.290;(3)区域内空间分布差异较为明显,土地生态状态改善与响应增强主要集中在土地生态压力过大的地方。据此可知,兰州市土地生态结构和功能基本完善,已步入良好阶段,但是各县区土地生态空间分布差异较大。

PSR model based evaluation on the spatiotemporal differences of land ecological security of Lanzhou City

The spatiotemporal differences of land ecological security of Lanzhou from 2006 to 2013 were studied through entropy weight method and comprehensive evaluation method with land ecological security eval-uation index system established with PSR model.The results showed that the land ecological security changed from'bad'in 2006 to'good'in 2013.Land ecological security pressure index decreased from 0.176 to 0.145,land ecological state and land ecological response index increased from 0.063 and 0.1 60 to 0.295 and 0.290 respec-tively.The regional spatial differences of land ecological security index were obvious,land ecological state im-provement and enhanced response mainly concentrated in the area under high land ecological stress.According-ly,the structure and functions of land ecological state has entered a good stage.