Demarcation Of "three Zones And Three Lines" In County-level Territorial Space Planning Based On "Double Evaluation"

Since the Reform and Opening-up,China has been facing increasingly serious problems such as resource shortage and ecological destruction.To solve this problem,the state has put forward the strategy of land space planning.As the research dives deeper,how to establish a practical "Double Evaluation" system in county-scale and reasonably delimit "Three Zones and Three Lines" to strengthen the control of territorial space has been actively explored by experts and scholars.Taking Fengxin County as an example,this paper analyzes and excavates the existing overlaps and deficiencies of the current Three Control Lines through empirical research.Based on the county scale,with the help of GIS technology,Fengxin county adopts a variety of evaluation methods,combined with local conditions,to construct the Double Evaluation system.Based on the result,principal component analysis was used to establish a four-dimensional "MOLA" model combining qualitative and quantitative analysis to identify the spatial pattern of Three Districts in Fengxin County.based on the whole area perspective,The ecological protection red line,permanent basic farmland protection red line,and urban development boundary of Fengxin County were tentatively adjusted by means of forwarding superposition,reverse deduction,and comprehensive coordination.And put forward Fengxin county territorial space optimization-related strategies.In order to provide scientific reference for policy-making and planning of relevant administrative departments at all levels.The main conclusions are as follows:(1)Among the current three control lines,the range of ecological protection red line,permanent basic farmland,and urban development boundary is 371.60km~2,412.27km~2 and 51.13 km~2 respectively,accounting for 22.54%,25.00%,and 3.10% of the total territory of Fengxin County respectively.Among them,the ecological protection red line includes all the extremely important ecological protection areas in Fengxin County,and the current protection scale of the cultivated land protection red line is too large.There is also a gap between urban development boundaries and current development.The existing three control lines are found to overlap with each other and lack control strength after superimposition;It mainly concentrates on the overlapping between the boundary of urban development and the red line of permanent basic farmland protection,and the current boundary scope of the industrial park in the south of the central city exceeds the current boundary of urban development.(2)Through the county scale Double Evaluation system,it is determined that a large portion of Fengxin county’s ecological protection system is the Most Important Area,and the rest of the land space is better for agricultural cultivation and urban construction.The proportions of the ecological importance of Fengxin county from high to low are 38.57%,24.38%,37.05%;The proportions of suitability grade from high to low are 48.80%,10.37%,and 40.83%,respectively.In the suitability evaluation of urban construction,the proportion of suitability grades from high to low is 45.25%,11.60%,43.16%.Based on the constraints of water and soil resources,it is determined that Fengxin county can carry the maximum cultivated land size of622.79km~2,the maximum urban population of 361,900,and the maximum urban construction land of 50.67km~2.Fengxin county has greater potential in agricultural farming,urban construction.Compared with the results of municipal Double Evaluation,the area of important ecological protection area is more comprehensive,and the scope of suitable agricultural cultivation and the urban construction area is more accurate.It can provide more accurate preliminary judgment for the subsequent demarcation of Three Areas and Three lines.(3)According to the delineation results of Three Zones and Three Lines in Fengxin County,the proportion of ecological,agricultural,and urban space is about45:52:3.The ecological space is concentrated in the Jiuling Mountains which is in the northwest of the county,and the Hualin Mountains in the central and southern parts of the county.Agricultural space is concentrated in the central hills and eastern plains of the county.The urban space is concentrated in the central urban area in the east of the county and the surrounding towns of Shangfu Town.The areas corresponding to the Three Zones are 630.03km~2,282.25km~2,and 42.99 km~2,respectively,accounting for38.24%,17.12%,2.61% of the county’s land area respectively.The Three Zones and Three Lines do not overlap each other and jointly form Fengxin county territorial space.Compared with the existing Three Control Lines,the scope of ecological protection red line is more comprehensive,including most of the Double Evaluation results of the ecological protection of Fengxin County,thus,is very important;The demarcation of arable land in the permanent basic protection red line is more operable to ensure the quality of arable land within the scope.The boundary demarcation of urban development is more reasonable,positioning the development of each township and determining the shape and scale of future development.(4)Fengxin county in the future should establish a consciousness of the bottomline sense and make policy within the Three Lines of Control.In the ecological space,ecological cultural tourism can be properly developed by combining with the surrounding towns of Jing ’an County;As for agricultural space,controlling the total amount of internal permanent basic farmland is highly needed;for urban space,strengthening the control of various construction activities in the space is highly needed.In the process of optimization,the central urban area should use land intensively,improve the efficiency of land use,increase the construction of all kinds of public service gathering,and connect with the surrounding towns to increase the agglomeration advantage of the central urban area.Townships should speed up by accelerating the pace of new-type urbanization development based on ecological background advantages and enhance the spatial aggregation effect of various factors based on the actual situation and development orientation.