研究重大突发事件下网络舆情传播中社会群体主题演化图谱构建，对重大突发事件的应急和维护社会稳定具有重要作用。文章基于LDA主题模型构建社会群体主题演化图谱，基于主题时序统计和主题频次统计构建社会群体主题热度演化图谱，基于JS散度和DFS算法构建社会群体主题路径演化图谱，并给出重大突发事件下网络舆情传播中社会群体主题演化图谱构建过程模型。研究发现：利用构建的模型可以对群体主题特征、主题热度影响因素及主题最优传播路径进行分析，发现重大突发事件下舆情演进态势和识别敏感舆情话题，从而进行正向的舆情引导，为重大突发事件下网络舆情治理提供新的参考视角。

Research on the construction of social group theme evolution mapping in network public opinion communication under major emergencies plays an important role in emergency response to major emergencies and maintenance of social stability. The article constructs social group theme evolution mapping based on LDA theme model, constructs social group theme heat evolution mapping based on theme timing statistics and theme frequency statistics, constructs social group theme path evolution mapping based on JS dispersion and DFS algorithms, and gives a model of the process of constructing social group theme evolution mapping in network public opinion communication under major emergencies. It is found that the model constructed in this paper can be used to analyse the characteristics of group themes, the factors affecting theme heat and the optimal communication paths of the themes, to find out the evolution of public opinion under major emergencies and to identify sensitive public opinion topics, so as to guide public opinion in a positive direction, and to provide a new reference perspective for the management of online public opinion under major emergencies.