Changing of Hinterland on Economic Linkages and Scope of Wuhan Metropolitan Area

In the last 55 years,because of the level of economic development,external economic linkages,spatial competitions with surrounding cities,the impact of external economic linkages of Wuhan City changed constantly.The model on economic linkages revealed several characteristics:the external economic linkages was significantly strengthened;the economic linkages with neighboring cities were increasingly closed and showed strong time inertia;affected by the geographical distance attenuation rule,the spatial distributions take Wuhan City as the center surrounded by three layers.By using breakpoint formula,this article revealed that the economic radiation space of Wuhan City was extruded by surrounding cities,and the hinterland was gradually smaller.According to the principles of the layer structure,zoning integrity,dynamic development and regional balance,and the factors of integrated strength of center cities,the background of regional development,spatial elements and flow,this article defined the area of Wuhan metropolitan area by using the strength model of economic linkages and the empirical algorithm combining with spatial flow.The area was that: the core layer(1+8 cities cycle),the external layer(surrounding provinces and cities,e.g.Hubei,Henan,Hunan,Jiangxi,Anhui).