| Along with the deepening advance of the revolution, it has entered into a transitional period of economic and sharply social change in our country. Environment questions caused by the rapid development of economy have become increasingly serious, and public awareness of environmental protection has gradually strengthened. The quantity of malignant mass incidents caused by environmental problems increased rapidly especially in recent years. In this context, this paper study on the environmental risk group events systematically can enhance our understanding of environmental problems, and provide reference for our country to prevent and control such events.There are many environmental risk group events, among them Xiamen PX and Sichuan Shifang not only typical, but influential, and compares the two can better grasp the characteristics of such events. So this paper takes Xiamen PX and Sichuan Shifang as the cases, analyze them on the basis of the theory of social risk, value-added theory and summarize the environmental risk group events can be divided into rational struggle and violent protests according to the different way of fighting. Then induces its uniqueness compared with other mass incidents: risk perception is the biggest incentive in terms of its causes; the number is large and growing in terms of its participants; result in policy of compromise in terms of government disposal.From the above understanding we can divided the environmental risk group events into four stages to further explore their evolution mechanism. The origin stage contains risk perception and triggering event, in this stage people’s awareness of future risks triggered into deep concern. The fermentation stage contains public opinion guide, risk amplification and network consensus, this stage the media played a vital role at the risk spread and the unity of the consensus. Outbreak period includes personnel gathered, improper administrative and fight, and in this period people choose different ways to express their demands. Follow-up period mostly ended in compromise policy.Causes of the environmental risk group events has the following aspects: on the psychological level, avoid effect increases the risk sensitivity, at the same time, people have a herd mentality; On the level of government’s response, on the one hand, the government response lag, on the other hand the emergency disposal has wrongdoing; In the system level, not only lack of the public participation in the EIA process, and lack of interest expression mechanism.In order to achieve the effects of governance and preventive, finally put forward the countermeasures for various reasons. First, we should improve people’s risk cognitive concept and strengthen the risk transmission channel; second, we should optimize the government response mode and promote governance ability of environmental incidents; third, we should strengthen the system construction and promote the open channel of public environmental aspirations. |