Study On Site Selection Of Pre-Qin Settlements In The Upper And Middle Reaches Of Yangtze River From The Perspective Of Flood Control

The security of cities has continued to exist with the development of human beings and the progress of civilization.In the process of site selection and construction for thousands of years,people always pay attention to and face the important aspect of flood control of cities.The pre-Qin period was the stage of the origin and formation of ancient Cities in China,in which a large number of city sites were born.The development of cities in different regions was independent of each other and kept in contact with each other.In the process of cultural integration,relatively unified idea and technical system of site selection was gradually formed.In this paper,the site selection and construction of major cities in the pre-Qin period in the middle and upper reaches of the Yangtze River are briefly summarized by the time-axis discussion of cultural period and case analysis of city sites,aiming to explore the internal relationship between the site selection of cities and flood control.The flood control of the pre-Qin city sites in the Yangtze River Basin has been promoted by generations of ancestors through continuous practice and trial and error.The wisdom of the ancients is condensed in the technology and theory of building the city,and the value of the ancient city is embodied in the practical experience and historical lessons.The flood control techniques,ideas and measures of pre-Qin city sites are explored from the perspective of cultural context and site selection,so as to make up for the lack of traditional understanding of pre-Qin city sites in the middle and upper reaches of the Yangtze River,and provide ancient wisdom of pre-Qin city sites for modern city flood control and planning.In the pre-Qin period,the settlements in the middle and upper reaches of the Yangtze River were in different geographical environment characteristics and cultural development stages,so the settlement selection and flood control inevitably produced different technical characteristics and philosophical thoughts.Through the site on-the-spot investigation method and case method and other methods,mainly on comprehensive research to comb,the results showed that the upper Yangtze river region in the cities of the pre-qin fortification technology to innovation,pass the middle region and two regional cities siting and flood control experience from the development course of "passive" to "active",namely "passive location preferences" to "fortify active in the water.The paper puts forward that the technology system of city site flood control has been formed initially in this period,which consists of three aspects: "the technique of controlling water according to local conditions","the technique of benefiting both the city and the city" and "the technique of revitalizing the city through planning and management".The flood control system of pre-Qin cities in the middle and upper reaches of the Yangtze River can be divided into three parts: dredging system outside the city site,water barrier system inside the city site,and drainage system inside the city site.It is concluded that the site selection of pre-Qin cities in the middle and upper reaches has the characteristics of stage and region,and the flood control of city sites has the characteristics of adjusting measures to local conditions,regional regulation and practical rationality.In the middle and upper reaches of the region,the wisdom of the location of the camp is different.The cities in the upper reaches of the region show the morphological characteristics of the cities following the landscape as a whole,while the cities in the middle reaches have the human settlement mode of "city and water depend on each other".The location of the two cities has the philosophy and value of "harmony between man and earth",and the flood control of the city site has the philosophy and value of "harmony between man and earth".This paper summarizes the flood control considerations of city site selection,construction technology and planning and management,which reflects the practical characteristics of pre-Qin city site planning and construction in the middle and upper reaches of the region.This paper reflects and prospects the technical methods,research theories,research perspectives and regional shortcomings of the study on the location of cities and flood control,in order to conduct a deeper study on the flood control of pre-Qin cities in the middle and upper reaches of the Yangtze River,and provide ideas for the current flood control of cities in the Yangtze River basin and even other regions.