Influence Scope of Yangtze River Belt Based on the Urban Spatial Structure
TU Jianjun;ZHU Yue;LI Qi;LIU Li;XIANG Wen;School of Geographical Sciences,Southwest University;Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment,Ministry of Education;
Based on the 129 cities in the Yangtze River Economic Belt, the comprehensive strength index model is used to measure its comprehensive strength and divide the strength grade. The economic radiation field strength model and the linear average direction model are used to measure the size and direction of urban influence, to reveal the urban cyberspace structure characteristics, and finally use the weighted voronoi diagram model to divide the urban economic impact zone. The results of the study show that:(1)The strength level of the Yangtze River Economic Belt was "pyramid" type, and the core, sub core, the node cities are banded and dotted gathers along the Yangtze River or the tributaries of the Yangtze River. The marginal cities are clustered in the upper and middle reaches. Taking Shanghai as the "locomotive",with Chongqing, Chengdu, Suzhou, and Wuhan as the "Bullet Trains" section of the city network spatial pattern was formed.(2)The Yangtze River Economic Belt formed the complex network space structure of "3 +1+ n", including three core regions, one main axis and N auxiliary axis. In space, the radiation force and force of 129 prefecture level cities show the characteristics of "high connection, agglomeration, low linkage and decentralization". There are "Matthew effect", but still strong radiation city around the city "under the light" phenomenon.(3) City Radiation direction and force of the direction are related to the flow direction of the Yangtze River. East-west direction is consistent with the Yangtze River extension.The direction of city influence flows through the Yangtze river.(4) The Yangtze River Economic Belt is divided into "4 + 5". The nine major economic impact areas include the core area of the Yangtze River Delta city agglomeration, the core area of the urban agglomeration of the middle reaches of the Yangtze River, and the five core areas. The scope of provincial boundaries have been broken up, the spatial pattern of the basin economy across administrative boundaries was formed.