Research On Spatial Simulation Of The GDP Distribution In Chengyu Economic Zone Based On DMSP/OLS Nighttime Light Images

Looking over the entire western area in China,the Chengyu economic zone has the best conditions and potential for development.The economic development of Chengyu economic zone has great significance to promote the economic development of the western region and even the whole country.So it is necessary to figure out the level of economic development and dynamic changes of the Chengyu economic zone.As one of the important socio-economic data indicators.Gross Domestic Product(GDP)can measure the level of regional economic development.However,GDP statistics data has difficult to break the limitations of traditional socio-economic statistics,and can not show regional economic differences.With the development of geographic information space technology,“Spatialization of GDP data” provides new research ideas and methods for the Chengyu economic zone research.This paper is using GIS and RS technology,based on the idea of spatialization of GDP by Sub-industrial Division,to stimulate the GDP spatial distribution of Chengyu economic zone during 2000-2012.The Spatialization of GDP data for 13 years and the dynamic space-time were analyzed.The purpose is to understand that level of economic development of the Chengyu economic zone.The main conclusions were as follows:(1)A new set of approaches with higher accuracy to spatial simulation of the distribution of GDP have been established.The paper is managed to work out the spatial simulation results for the distribution of GDP in Chengyu economic zone based on the spatial modeling of GDP for different industries and regions,simulating the output values of the secondary and tertiary industry by virtue of the DMSP/OLS nighttime light images,simulating the output values of primary industry by means of land use data.In the course of spatial simulation,the paper extracts respectively by different approaches the nighttime light images from the spatial simulation of the output values of the secondary and tertiary industry to improve the accuracy of the simulation results.Of the nighttime light images extracted,the paper analyzed the images extracted through the exclusion of depopulated areas,by way of light threshold method and by means of neighborhood statistics analysis(NSA)method.By systematically comparing different ranges of DMSP/OLS nighttime light images extracted from spatial simulation of GDP distribution,it is found that a higher accuracy is embodied in the GDP simulation results,which are thus determined for the further study in this paper,of DMSP/OLS nighttime light images extracted by virtue of neighborhood statistics analysis(NSA)method.The paper eventually obtains the result with higher accuracy out of spatial simulation of GDP distribution in Chengyu economic zone by combining the result out of simulation of the output values of the secondary and tertiary industry and that of the primary industry based on land use data.(2)The temporal and spatial distribution characteristics of GDP in Chengyu economic zone are analyzed.In terms of temporal patterns,the GDP value of a single pixel in the Chengyu economic zones over the period of 2000-2012 shows an increasing trend,especially since 2008,the GDP growth of a single pixel is more obvious.In terms of spatial patterns,the highest GDP value of a single pixel is distributed in Chengdu areas and main urban areas of Chongqing.According to the distribution of individual GDP value,it can be seen that the economic development level of Chengyu economic zone illustrates the hierarchical characteristics that the economic development level in Chengdu areas and the main urban areas of Chongqing is higher than that of other prefecture-level cities and municipal districts,and the economic development level of other prefecture-level cities and municipal districts is higher than that of other districts and counties governed by the prefecture-level cities and municipal districts.(3)The change trend of GDP in Chengdyu economic zone is analyzed.The regions with a rapid change of GDP growth mainly serve as the Chengdu areas and the main urban districts of Chongqing,and the GDP growth of other prefecture-level cities is relatively fast.In terms of the secondary economic zones.Those economic zones whose GDP growth rate is changing from the fast to the slow range successively from “one hour economy circle” of Chongqing,to Chengdu economic zone,to economic zone in the south and northeast of Sichun,and to economic zone in the northeast of Chongqing.(4)The GDP gravity center of Chengyu economic zone is analyzed.The GDP gravity center was located in the northwest of the geometric center.From 2000 to 2012,the GDP gravity center of Chengyu economic zone has been focused on the lining center of Chengdu area and the main urban districts of Chongqing,and moves from northwest to southeast of the economic zone.(5)The economic activity sub-zones in Chengyu economic zone are estimated and ranked by ArcGIS hydrological analysis tools,and by DMSP/OLS nighttime light images and spatial simulation results obtained in 2012 of GDP distribution in Chengyu economic zone.The results manifest that the Chengyu economic zone contains two top-level economic activity areas,one sub-high-level economic activity area,eight medium-sized economic activity areas,27 sub-low economic activity areas and 60 lowest-level economic activity areas.The level of the economic activity area is closely related to the city rank it is contained,and the rank relationship of each economic activity area is associated with the degree of associative and administrative relationship between cities to which the economic activity area is affiliated.