| The concept of "ghost town" entered the public for the first time was proposed by the article "Kambas: An Empty City" in the 2008 American Time Magazine.“Ghost city” mainly refers to the extensive reproduction of urban construction land during the urban development process,which leads to the inability to form a good fit between urban development,population resources and natural environment,resulting in low housing occupancy rate,high vacancy rate and night horror.It is dark and silent,like a ghost town.The phenomenon of "ghost town" is closely related to social and economic development and people's lives,and has aroused widespread concern.Since the reform and opening up,China's urbanization process has been accelerating.From 2000 to 2017,the urban population increased from 459.06 million to 813.47 million,with a growth rate of77.2%.The urban construction land area increased from 22,114 square kilometers to 55,155 square kilometers.The growth rate is 149.4%.The growth rate of urban construction land area is much higher than that of urban population,which has caused the phenomenon of “ghost town” with low housing occupancy rate and high vacancy rate in some urban areas.However,scholars' research on the phenomenon of "ghost city" is mostly judged by social,economic,population and other statistical data.The research level is also concentrated on the comparison of the degree of ghosting between different cities,and less on the internals of a certain city.The distribution of "ghost town" phenomenon.Therefore,with the continuous deepening of the comprehensive application of remote sensing technology,combined with the spatial information needed for remote sensing data,especially multi-temporal remote sensing data extraction,the Chinese “ghost city” phenomenon is studied more accurately,not only for the evolution ofurban spatial pattern and time.The analysis provides an effective method and can also provide decision makers with a reliable reference for future urban planning and environmental management.Based on the rapid development of urbanization in Zhengzhou City,this paper first uses the daytime satellite data(Landsat image)to calculate the landscape pattern index of each administrative region in the study area and analyze the urban expansion and its changing characteristics of each administrative region.The annual average expansion index of Zhengzhou City is calculated based on the1km*1km unit grid.Then combined with the nighttime satellite(DMSP / OLS)data,through the time-matched characteristics of the two sets of satellite data,the correlation analysis of the remote sensing data changes of different time images in Zhengzhou City was carried out,showing Zhengzhou City from2001 to 2007 and 2007 to 2013.In the two time periods,the spatial pattern and time evolution of construction land and nighttime lighting will be used to verify and analyze whether there is a clear “ghost town” phenomenon in Zhengzhou City,especially in Zhengdong New District.The main conclusions of this study are as follows:(1)Using the daytime satellite data,calculating the landscape pattern index and judging the expansion type of each administrative area in combination with the urban expansion measure,the study found that during the period from 2001 to 2013,Jinshui District(including Zhengdong New District)is a typical dual-core expansion model..The results show that: 1 Jinshui District presents a dual-core expansion model with Zhengdong New District as the core of new urban growth,especially during the period from 2007 to 2013.The expansion of Zhengdong New District as a sub-city center is very obvious,with the original Jinshui.The district has formed a clear trend of dual-core development;2 Huiji District presents a restrictive expansion model under natural conditions;3 urban districts present a policy-orientedexpansion model;4 Zhongyuan District presents a policy-oriented(edge)expansion Mode;5 Zhongyuan District presents an economic-led extensional expansion model under the constraints of natural factors.(2)Quantify the urban expansion index and spatial distribution characteristics of different administrative regions on the basis of the unit grid.The study found that during the period from 2001 to2013,the Jinshui District(including Zhengdong New District)expanded rapidly compared with the Huiji District.The high-speed expansion ratio is high.The results of the study show that the degree of expansion of construction land in each administrative district from 2007 to 2013 is much greater than the degree of expansion from 2001 to 2007.During the period from 2007 to 2013,the rapid expansion and rapid expansion of Jinshui District reached 16.81%,9.83%;the Central Plains area was 16.07% and 11.83%,respectively;while the Huiji District has no grid to achieve rapid expansion and rapid expansion is only6.36%;(3)Combining daytime satellite data and nighttime satellite data,the standard ghost ellipse analysis method is used to analyze the phenomenon of “ghost town” in Zhengzhou.The study found that during the period from 2007 to 2013,the elliptical center movement distance of nighttime lights was significantly smaller than that of construction land.The extent of the movement.From the analysis and comparison results,it can be clearly seen that the elliptical center of Zhengzhou construction land has been moving to the southeast,and the construction land has expanded to the southeast in a large extent,especially in the current Zhengdong New District,while the elliptical center of the night light has a significantly smaller moving distance.The extent of construction land movement.(4)Analysis of Pearson correlation analysis and standard deviation ellipse analysis The “ghost city” phenomenon mainly occurred in Zhengdong New District.The study found that there was a clear“ghost city” phenomenon in Zhengdong New District from 2007 to 2013.The results of the pearsoncorrelation analysis fully prove that the “ghost city” phenomenon in the old Jinshui area is mainly concentrated in the Zhengdong New District.Finally,the standard deviation ellipse analysis was used again to confirm that there was a clear "ghost town" phenomenon in Zhengdong New District from 2007 to 2013. |
PDF Full Text Request