Study On Optimal Allocation Of Urban Land In Linchuan District Based On Ecological Security

With the rapid development of urbanization in China,the scale of cities and towns has expanded significantly,and cultivated land,forest land and other types of land have been occupied by human development activities,the contradiction between people and land has become more prominent.In order to protect the earth's homeland on which human beings depend and realize the healthy development of cities,our country pays more and more attention to the construction of ecological civilization.In the process of making relevant planning,such as urban planning and land use planning,we attach great importance to coordinating the relationship between cities and ecological environment,and restrict the absence of cities and towns by delimiting ecological red line protection zones and permanent basic farmland protection zones.Ordinal expansion.These measures have played a positive role in the protection of ecological environment and the healthy development of cities.However,the existing development model of restricting"planning"by"planning"has obvious disadvantages.It is often difficult to make a choice between environmental protection and urban development,which is not conducive to coordinating the relationship between cities and the environment.Applying the concept of ecological security to the process of urban development can provide a more scientific and just coordination method for the contradiction between urban and ecological environment,and provide a reference for relevant practitioners,so as to promote the sustainable use of land resources and realize the sustainable development of the region.This paper takes Linchuan District of Fuzhou City as an example.Firstly,11evaluation factors are selected from three aspects:engineering geological factors,disaster avoidance factors and natural ecological factors to construct the ecological security evaluation system.Through the integration of the evaluation results of each factor,the ecological security evaluation results of Linchuan District are obtained,and the evaluation results are taken as the basis of urban spatial optimization.Then the land use type data of Linchuan District in 1995,2005 and 2015 were obtained from remote sensing image interpretation,the transfer matrix of land use type was calculated,the suitability atlas was made,and the land use pattern of Linchuan District in 2025 was simulated by CA-Markov simulation method,which served as the basis for optimizing urban spatial layout.Finally,through the coordination of the results of ecological security assessment and land use change simulation,the process of coordination takes into account the direction of urban development and functional zoning,and obtains the results of urban spatial optimization.The main conclusions of this study are as follows:(1)There are obvious regional differences in the results of ecological security assessment in Linchuan District,among which the high-security areas are mainly located in the north and west of Linchuan District;the low-security areas are mainly located in the southern mountains of Linchuan District,the western margin,and there are small areas of low-security areas in the south of towns.(2)From 1995 to 2015,the land use types in Linchuan area changed significantly.The area of woodland and arable land decreased year by year.The woodland was mostly converted to arable land and grassland,and arable land was mostly converted to construction land.The area of urban land expanded rapidly,mainly from arable land and woodland to forestland.The change range of grassland and water area was small.It shows that Linchuan has developed rapidly in the past 20 years,the area of construction land has expanded significantly,and a large number of cultivated land has been exploited as construction land.(3)The results of CA-Markov simulation show that the land use types in Linchuan District have changed significantly in 2025,and the area of construction land will continue to expand from 11373.32 hm~2 in 2015 to 22354.40 hm~2 in 2025.Towns in the west,southeast has a significant extension,in the Northeast there is also a small area of increase.(4)Through the study of urban development direction and functional zoning,it is found that the urban development in Linchuan prefers to expand toward southeast.The urban land in Shangdongdu Town has the conditions of eastward development,the urban land in Zhanping Township can expand northward,and the urban land in Wenchang Street can continue to develop northward and eastward.The urban space in Linchuan District can be divided according to the development characteristics of each part.For the core area,the northern industrial zone,the southern industrial zone and other different types of zones.(5)Firstly,through the integration of the results of ecological security assessment and urban expansion simulation,the urban land area in 2025 was optimized.Then,the urban land space was further optimized based on the analysis results of urban expansion direction and functional zoning,and the final range of urban land in Linchuan District in2025 was obtained.