Abstract:

The Yangtze River Economic Belt is becoming a national strategy and the Yangtze River Economic Belt will become the economic backbone of China. Nanjing metropolitan area is an important member of the Yangtze River Economic Belt. Nanjing metropolitan area is the fringe of the Yangtze River Delta city group and Wanjiang City Belt. The development of Wanjiang City Belt depends on Nanjing metropolitan area to be in line with the Yangtze River Delta city group actively, so the development of Nanjing metropolitan area is of great importance. Nanjing metropolitan area includes eight cities, and they are Nanjing, Yangzhou, Zhenjiang, Huaian, Maanshan, Wuhu, Chaohu and Chuzhou. Taking the Nanjing metropolitan area as an example and choosing four typical years of 1993, 1995, 2005 and 2011, the article uses the Spatial Analyst function of ArcGIS and gravitymodel to calculate the accessibility and economic linkage and the regional economic linkage gradation of Nanjing metropolitan area. Then the article studies the evolution of the regional economic linkage pattern and the maximum economic linkage direction of each city in Nanjing metropolitan area. Results are shown as follows.（1）The accessibility of Nanjing metropolitan area is improved evidently, and the average accessibility of Nanjing metropolitan area is improved obviously, too. But the increase amount of accessibility of each city is different.（2）The economic linkage of Nanjing metropolitan area is strengthening increasingly. The economic linkage pattern of Nanjing metropolitan area is changed from point axis pattern to network pattern and Nanjing is becoming the center city of the regional economic linkage of Nanjing metropolitan area.（3）Studying from the regional economic linkage gradation, Nanjing is the spatial linkage agglomeration center of Nanjing metropolitan area. The economic linkage pattern of Nanjing metropolitan area is around Nanjing. Nanjing is just like the moon and other cities are like the stars