Study On The Spatial Expansion Of Wuhan Urban Development Zone In 2000-2015

After entering new century,China’s urbanization process accelerated,urban land use pattern is undergoing major changes.The expansion of urban construction land as well as the reduction of cultivated land and forest land area are the most obvious characteristics of land cover change.As the core city of central China,with the implementation of the strategy of "the rise of central China" the demand of urban construction land is increasing day by day,and the sustainable development of population,resources and environment becomes an urgent problem to be solved in Wuhan.Therefore,it is very necessary to study the spatial expansion of Wuhan urban development zone and its consistency with urban planning.This paper takes Wuhan City as the research object,which includes both the main city of the 7 areas and the rapid development of urban areas.On the base of 2000,2005,2010 and 2015 four periods of land use data,This paper through the dynamic degree of land use,land use index method the pattern of land development space in the past 15 years.Then this paper uses the different parameters of city construction land expansion,the center of gravity transfer model,azimuth quadrant analysis method and extended mode method from multi angle in-depth study of Wuhan city construction land expansion of the temporal and spatial characteristics.Finally,In order to reveal the guiding role in City planning in spatial expansion,this paper combines the overall planning of Wuhan City 2010-2020 years and takes 2010 as base year and 2015 as the target year,then uses gravity migration consistency,spatial expansion consistency and spatial layout consistency to find the existing problems in the development of the city and proposes some suggestions for the rational development of the city.The conclusions are as follows:(1)In 2000-2005year,The number of land use structure of Wuhan City Development Zone changes significantly.The growth of construction land increased most greatly and its value has reached 55304 hectares.While the cultivated land,forest land,water area and unused land have different degrees of reduction.The largest reduction is cultivated land,up to 49303.8 hectares.This shows that the contradiction between cultivated land and construction land is the main characteristic of urban spatial expansion.In addition,from all over 2000-2015year,the amount of water area changes tended to reduce and the grassland presents a slight increase.This shows that the expansion of urban construction compressed the ecological space and added to the pressure on the ecological background.(2)The spatial expansion of Wuhan shows obvious difference in time and space.In terms of the number of construction land,the growth rate of construction land area in 2005-2010 and 2010-2015 was higher than that in 2000-2005,and the dynamic degree and the expansion intensity increased significantly.From the perspective of each quadrant,2000-2015,SEE and NNW construction land expansion intensity is more prominent.From the point of view of the gravity center,the center of gravity of the construction land is unstable,which migrated to the southwest in 2000-2005,moved to the southeast in 2005-2010 and moved to the southeast in 2010-2015.The migration rate decreased first and then increased.From the urban morphology changes,the construction land compactness index is low all over 2000-2015 year and in a relatively loose state.In time series,it trends to be declining after rising.It shows that the city changes from tight to loose.But the fractal dimension decreased and the stability coefficient appears a slight rebound after significantly decreased in the early.It shows that the overall development of the city is in a more regular and more stable state(3)Pattern evolution characteristics of land expansion of Wuhan City Development Zone:In 2000-2015 years,the sprawl pattern always occupies the dominant position.In early time,the filling type expansion of the main city land tends to saturation and it accelerated the expansion of the enclave.Finally it led to the further development of urban land to the outside space,providing blank for the spread of sprawl.From the difference in spatial distribution of view,the hot spots is in Jiangxia area and Hongshan area;filling type expansion mainly occurred in the main city and tending to move forward to the peripheral;enclave expansion always focused on the urban periphery,especially in Jiangxia area,Dongxihu area and Huangpi area.The spatial pattern of urban development zone of Wuhan is gradually showing the "central city" and"six big satellite cities" state.(4)The consistency research about the expansion of urban construction land and urban planning in Wuhan shows that:2010-2015 years of City Spatial Gravity migration direction accords with the expected direction of city planning,but the migration speed slightly slower.In the direction of urban space development,the direction of NEE is limited due to the limitation of natural conditions and the development of the other is good.Urban space initially showing the central city and six satellite city pattern.In the space layout consistency,the function of land expansion faster than expected and the completion rate is high.But there exists spatial inconsistency.The coincidence rate of commercial land and scientific land is good,and the rate of industrial land is poor.