Urban And Rural Spatial Optimization Strategy Based On Ecological Security Pattern

As an important spatial planning pattern for maintaining regional ecological stability,ecological security pattern is one of the important bases for coordinating regional ecology and economic development,optimizing ecology and constructing environmental development framework under the current background of land planning implementation.Therefore,this paper takes Garze Prefecture of Sichuan Province as an example,and based on the land use data of Garze Prefecture in 1998,2008 and 2018,constructs the ecological security evaluation system of Garze Prefecture,evaluates the ecological security of four types of landscape land in each city and county,and obtains the regional comprehensive ecological security level and changes.The current ecological security pattern was constructed through the selection of sources,the construction of resistance surfaces and the extraction of ecological corridors.Based on ecological security pattern selecting and driving factors of land use change,development and ecological protection set inertia under two scenarios,based on two kinds of situations at the same time,the scope of suitability for the influence elements,using the CA-Markov model for suitability atlas(i.e.,the impact factor constraints)model 2028 t of sex of land conversion.Finally,the paper puts forward optimization strategies for ecological space and urban and rural development through analyzing the changes of ecological environment in Garze Prefecture under different simulated scenarios and the existing ecological problems in the region.The main research methods and conclusions are as follows:(1)Based on the land use data of Garze Prefecture in 1998,2008 and 2018,the land use change status and land use status in the region were analyzed through GIS.Based on the research on ecological security evaluation at home and abroad and the current situation of land use pattern in Garze Prefecture,the ecological security evaluation system and evaluation model of Garze Prefecture were constructed by selecting the landscape indicators in the landscape ecological security evaluation system for the ecologically sensitive areas in the alpine cold region.At the same time,the entropy weight method was used to determine the weight of the evaluation factors.The land use data of Garze Prefecture in 1998,2008 and2018 were selected to evaluate and study the four ecological landscape lands of cultivated land,woodland,grassland and water area,and the comprehensive ecological security level of each city and county in Garze Prefecture from 1998 to 2018 was obtained through superposition analysis.The results show that the overall ecological security in Garze Prefecture presents a downward trend,and the overall ecological security in Garze Prefecture has an obvious decline from 2008 to 2018 due to urban construction and further development of ecological resources.(2)Mathematical statistics are used to analyze the land conversion trend of Garze Prefecture in the past 30 years.Specifically,the area of construction land in Garze Prefecture doubled during the research period,and the main growth points of urban space were distributed in the river valley and along the important spatial corridors.Through nearly 30 years of land conversion regularity,to explore the driving factors of land use change,t,the results show that t he land ecological landscape mainly by topography,traffic,rivers,and the influence of the existing construction land distribution location,based on the urban-rural spatial development,t he made the ecological constraints and suitability.(3)Land use conversion of Garze Prefecture in 2028 under the "inertia development" scenario and the "ecological protection" development scenario was simulated by CA-Markov model.The evaluation results show that under the "inertia development" scenario,the fragmentation degree of each land use type is high,the connectivity between ecological landscapes is poor,and urban construction has a large degree of interference to the ecological environment.Under the "ecological protection" scenario,the ecological landscape has a high degree of connectivity and aggregation.On the premise of ensuring important ecological resources,the development demand of construction land can be satisfied to the maximum extent.Therefore,this scenario can better coordinate the relationship between regional economic development and ecological protection.(4)According to the ecological security evaluation and simulation of land use change situation,is proposed for the spatial pattern of urban and rural areas,t to "source,corridor,development group,strategic nodes" as the core of a multi-level ecological space pattern,and from the function zoning,corridor layout and urban construction of three aspects put forward concrete ganzizhou urban-rural spatial optimization strategy.