Research On Risk Assessment And Management Of Regional Emergent Environmental Events Based On Entropy Weight-set Pair Analysis

The regional environmental risk assessment is characterized by the complexity,cumulative nature,and uncertainty of its risk sources and risk receptors,which leads to the ambiguity of the assessment results,which has become the focus and difficulty of the current environmental risk assessment field.In order to solve the uncertainty problem in the assessment process,this paper constructs a regional emergency environmental risk assessment model based on the entropy weight theory and set pair analysis theory.Based on the set pair analysis theory,it establishes a multiple connection degree to the risk The certainty and uncertainty of the evaluation are handled in a unified manner to provide theoretical guidance and basis for further reducing regional environmental risks.Based on the characteristics of regional environmental emergencies,on the basis of"Recommended Methods for Risk Assessment of Environmental Emergencies in Administrative Areas",through the screening and elimination of indicators,a target layer（1 indicator:regional environmental emergencies risk assessment was constructed）,The criteria layer（3 indicators,namely:environmental risk sources,vulnerability of environmental risk receptors and environmental risk prevention and emergency response capabilities）and the indicator layer（20 indicators）,a total of 24indicators.Analyze the selected qualitative indicators using triangular fuzzy quantization,and divide the environmental risk into four levels according to the principle of risk classification:high risk,high risk,medium risk and low risk.Taking Fuling District in Chongqing as an example,the constructed entropy weight-set is used to evaluate the risk of the analysis model.The comprehensive connection degree of risk assessment of Fuling District in Chongqing is obtained as （?）=0.120+0.0554)₁+0.2244)₂+0.5985).When the confidenceλis y₁+y₂+y₃+y₄=0.120+0.055+0.224+0.598>0.7 and If y₁+y₂+y₃<0.7,the evaluation level is 4,and the evaluation result of this area is a low-risk area.Through the analysis of indicator weights and the analysis of indicator connection components,X1（number of environmental risk companies per unit area）,X3（percentage of environmental risk companies above a larger area）,X9（number of permanent residents per unit area）,X10（The number of environmental risk receptors per unit area）,X15（pollutant interception,dilution and disposal capacity）,X16（environmental emergency plan preparation）and X18（emergency material reserve situation）evaluation index weights are larger;X4（road transportation hazardous chemistry The number of products）,X11（the number of centralized drinking water sources in townships and above）and X12（the number of population serving the centralized drinking water sources in townships and above）are high-risk indicators.Finally,according to the analysis results,the corresponding environmental risk management is proposed for the evaluation indicators of environmental risk sources,environmental risk receptor vulnerabilities,and higher and higher risk levels in environmental risk prevention and control and emergency capabilities,and indicators with larger weight values.