Study On Ecological Environment Capacity From The Perspective Of Life Cycle Theory Of Towns In Sichuan Tibetan Region

This paper is a sub-project under the project of National Natural Science Foundation of China("No.51578454"),which is based on the theory of system complexity and the ecological optimization mechanism of urban spatial structure in Sichuan Tibetan area.Sichuan Tibetan region has always had its unique social culture and development process,and is strongly restricted by the fragile ecological environment.In recent years,large-scale construction has been carried out in this region.However,due to the lack of exploration of its own orderliness and suitable mode,the ecological environment problems have become increasingly prominent.Therefore,excavating the inherent evolution regular of towns in Sichuan Tibetan region from the time dimension,exploring the ecological environment and the development situation in different periods,in order to find out the drawbacks and constraints in the evolution process,and to clarify the incorrect development mode,which is conducive to putting forward the strategies suitable for the region,and avoiding the towns falling into the contradiction between development and ecological protection.Starting from exploring the resources environment condition and retrospecting historical development of Sichuan Tibetan region,this paper sorts out the evolution process of different types of towns and the characteristics of regional overall changes,then sums up the regular of life cycle development.Further,qualitative and quantitative methods are combined to analyze the ecological environment capacity of different towns in different life cycle stages,which is to explore the ecological constraint framework that affects regional development,and to propose specific instructive strategies.The paper is divided into the following sections:The first is background and basic research.The life cycle theory,ecological environment capacity and other related theories and researches are analyzed and summarized.The basic situation,resources and environment,social and economic development,and historical process of Sichuan Tibetan region are preliminarily sorted out to provide basic research data for the following chapters.Secondly,the life cycle of Sichuan Tibetan region is studied.The evolution process of specific towns is selected from different forms and types.The characteristics of different periods are studied from the aspects of quantity,construction land and spatial distribution,then the life cycle stages of the region are summarized.Then is the analysis of ecological environment capacity based on the life cycle.From three aspects of resource carrying change,the evolution process,as well as social and economic development,choosing specific elements and methods from various levels to analyze typical towns,by summarizing and comparing the analysis results,putting forward different development modes and constraints in the process of life cycle.Finally,the development strategies are proposed according to the framework of ecological environment constraints.