Modeling of urban ecological safety evaluation based on fuzzy matter-element theory

Urban ecological safety evaluation is an important way to coordinate economic development and environmental protection and to promote urban sustainable development. This paper constructed an evaluation indicator system of urban ecological safety. The indicator system was composed of vigor, organization, resilience, maintenance of ecosystem service and human health. Then it discussed evaluation grads and standard values of indicators. Considering the illegibility and uncertainty in ecological safety evaluation, the paper combined fuzzy mathematics and matter-element theory to establish an evaluation model. Finally it developed a case study on Guangzhou city from 1991 to 2007. There is a tendency of gradual improvement in ecological safety of Guangzhou. However, safety conditions during the study period belong to “critically safe” grade, so ecological safety conditions of Guangzhou are unsatisfactory and need to be improved. Fuzzy matter-element theory is scientific, simple, and practical for multi-objective decision-making problems of safety evaluation.