基于PSR-TOPSIS模型的郑州市土地生态安全评价及障碍因子诊断

Evaluation and obstacle factor diagnosis of land ecological security in Zhengzhou based on PSR-TOPSIS model

利用PSR模型、TOPSIS模型及障碍度模型等研究方法,对郑州市2003—2017年土地生态安全进行动态评价并定量化分析识别主要障碍因子。结果表明:(1)郑州市土地生态安全状况改善明显,2003—2007年表现为小幅度降低,2007—2011年转化为缓慢上升,2011—2017年呈现为快速上升阶段,生态安全水平从Ⅳ级上升到Ⅱ级;(2)生态环境各子系统间的演变存在差异,状态和响应子系统提升显著,安全水平从Ⅴ级提升到Ⅱ级,但是压力子系统提升缓慢,仍然处于第Ⅲ级水平;(3)土地生态压力子系统障碍度逐年升高,成为主要限制因素,主要障碍因子为农业机械化水平、当年造林面积、人口密度等。总体来看,郑州市土地生态安全发展状况良好,处于良性发展状态,但应采取措施消除主要障碍因子的不利影响。

Using the PSR model, TOPSIS model and obstacle degree model and other research methods, the dynamic evaluation of land ecological security in Zhengzhou from 2003 to 2017 was carried out, and the main obstacle factors were quantitatively identified and analyzed. The results show that:(1)the land ecological security situation of Zhengzhou City had improved obviously, which had been reduced in a small extent from 2003 to 2007, transformed into a slow rise from 2007 to 2011, and presented a rapid rise from 2011 to 2017, with the ecological security level rising from level Ⅳ to level Ⅱ;(2)there are differences in the evolution of each subsystem of the ecological environment. The state and response subsystems are significantly improved. The security level has been upgraded from level Ⅴ to level Ⅱ,while the pressure subsystem has been slowly improved and is still at level Ⅲ;(3)the obstacle degree of land ecological pressure subsystem,having become the main limiting factor,is increasing year by year, which was the main limiting factor, and the main obstacle factors include agricultural mechanization level, afforestation area and population density, etc. In general, the land ecological security development in Zhengzhou is good and in a benign state, but measures should be taken to eliminate the adverse effects of major obstacle factors. The research method can provide reference for the diagnosis and evaluation of ecological security in rapid urbanization areas.