中文摘要：

合理的风险共担是推动建筑节能改造项目顺利开展的重要保障。既有建筑节能改造项目风险共担具有复杂的系统特性，其风险共担结构会受到项目内外部环境因素的影响而发生动态演化。利用生态学中的生态位理论对风险共担结构演化的主体协同竞争机理、态势影响关系、突变调控机理与稳态适应度机理进行阐述，并系统分析各个机理之间的交互作用机制，为既有建筑节能改造项目实现科学的风险管理提供参考。

英文摘要：

The reasonable risk sharing is an important guarantee for the smooth development of the energyefficiency reconstruction projects of existing buildings. The risk sharing structure, which is characteristic ofcomplex system, is likely to evolve dynamically due to the internal and external environment factors of theprojects. Based on the Niche theory in ecology the paper discusses the evolutionary rationale like the synergeticand competitive mechanism of the project participants, the situational influence relation, the mutation regulationmechanism, the mechanism of steady state fitness and so on. Also, it analyzes the interaction between variousmechanisms in order to provide a reference for the energy efficiency reconstruction projects to achieve scientificrisk management.