Study on ecological security evaluation of Beijing city

The construction of urban ecological security is much concerned with the continuous urbanization process. This paper established an urban ecological security evaluation system by employing PSR (Pressure-Status-Response)method, on the basis of the previous studies about ecological security evaluation by other researchers. The weight of each index was defined utilizing the AHP(Analytical Hierarchy Process) method, and the situation of ecological security in Beijing during 2000-2004 was evaluated. The result shows that ecological security of Beijing during this period lie in the situation of "relatively not secure", and the main contribution factors are water resources of great pressure and undesirable air quality.