On the County Economic Differences of the Urban Agglomeration in the Chengdu Plain

County-level economy is the basic unit of the national economy.A full knowledge of the spatial and temporal differences of a county is of vital importance for promoting the healthy development of the county economy.Taking the county as a research unit, a comprehensive economic evaluation index system was constructed based on the economic indicators data of56 counties within the urban agglomeration of the Chengdu Plain, and by means of principal component analysis, a comprehensive examination is made to investigate the main components and the overall scores of the counties’ economic performance of the urban agglomeration in the Chengdu Plain in the years of 2000, 2005, 2011 and 2015 and a ranking is given to each of the 56 counties according to the scores thus obtained.The variation map of county economic development level within the urban agglomeration in the Chengdu Plain was drawn by GIS.The economy of each county was then categorized into four:the developed economy, the relatively developed economy, moderately developed economy, and underdeveloped economy after the cluster analysis, and the map reflecting county economic differences at four different points of time was drawn so as to reveal the laws of spatial and temporal differences variation of county economic development.The findings were intended o provide a reference for the realization of the scientific positioning of each city and the making of the strategy for long-term development of the urban agglomeration in the Chengdu Plain.