Abstract:

The evolution of urban agglomerations is a process of competition and symbiotic interaction.The concept "competition" refers to that cities in urban agglomeration are competing with each other to obtain favorable development status and conditions,and "symbiosis" refers to that cities are interdependent,mutualsupport and under unified planning of the agglomeration development.The connotation and fundamental characteristics of city symbiotic relationship include that the space locations of cities in the agglomeration are approachable,the cooperation time is longterm,individuals are interdependent on each other,and the function relations are mutualsupport and coordinated.Based on the principles of system theory,it was proposed that the relationship of competition and symbiotic interaction can be divided into four stages: weak symbiotic interaction and weak competition stage,strong competition and weak symbiotic interaction stage,strong symbiotic interaction and strong competition stage,weak competition and strong symbiotic interaction stage.The evolution of the relationship between competition and symbiotic interaction exhibited periodic characteristics,which are demonstrated by the actual evolution process of cities and regions.Moreover,competition and symbiosis in urban agglomeration can be divided into four space dimensions: competition and symbiosis inside the urban agglomeration,competition and symbiosis outside the agglomeration,competition outside the agglomeration and symbiosis inside agglomeration,and competition inside the agglomeration and symbiosis outside agglomeration.At last,the paper initially summarized the development model of competition and symbiosis of urban agglomerations.

Key words: competition, symbiosis, urban agglomeration, time division