Temporal And Spatial Differentiation Of Urban And Rural Non-construction Land Conversion And Its Management And Control Countermeasures

High-intensity human activities have profoundly changed the scale,structure and layout of urban and rural non-construction land such as mountains,rivers,forests,fields,lakes,grasses,sand and ice.The scientific utilization,protection and development of nonconstruction land is the core content in implementing the concept of a community of life in mountains,water,forests,fields,lakes,grasses,sand and ice,meeting the needs under ecological civilization era and realizing sustainable development.In the process of rapid urbanization,due to the intensified urban scale expansion and the increasing demand for land development and utilization,urban and rural non-construction land with ecological utility,such as cultivated land and forest land,have been continuously occupied and destroyed,and the number has decreased significantly,with functional alienation.As a result,there is an urgent need to effectively reveal the urban and rural non-construction land conversion process,regular characteristics and influencing factors,and to propose targeted planning and protection strategies,so as to provide scientific basis for the protection and restoration of natural ecosystems including mountains,rivers,forests,fields,lakes,grasses,sand and ice.On the basis of clarifying the connotation and theoretical analysis of the conversion of urban and rural non-construction land,with Suzhou City as the research object,this paper determines the classification system using remote sensing image data in 1995,2000,2005,2010,2015,and 2020,explores the temporal and spatial evolution characteristics and influencing factors of non-construction land conversion,and proposes relevant management and control countermeasures.Firstly,this paper explores the temporal and spatial pattern characteristics of non-construction land in the past 25 years,as well as its variation range and speed by means of land use dynamic degree and other methods;secondly,this paper selects land by means of transfer matrix,center of gravity migration,and geographic information map analysis to analyze the conversion of non-construction land in Suzhou over the past 25 years in terms of quantity,reveal the spatial flow characteristics of nonconstruction land conversion from the city and town levels in terms of space,thus systematically exploring the temporal and spatial differentiation pattern of urban and rural non-construction land conversion in Suzhou from 1995 to 2020;next,this paper selects 9index factors including social and economic factors(transportation,public services,regional GDP,population,urban land proportion,land use degree)and natural environment factors(elevation,slope and terrain relief),and quantitatively explores the influencing factors of Suzhou urban and rural non-construction land conversion with the help of geographic detectors and correlation analysis methods;Finally,this paper proposes targeted management and control measures from the overall and regional levels of Suzhou City.The main conclusions of this paper are as follows:(1)The urban and rural non-construction land with cultivated land as the main body continued to decrease,and the water area increased slightly.In a single dynamic degree,the change rate of cultivated land is the fastest,reaching the maximum value during 2005-2010;in addition,the comprehensive dynamic degree of non-construction land was also the most active from 2005 to 2010,and then decreasing year by year.(2)The conversion of urban and rural non-construction land includes the initial smooth,rapid reduction and stable recovery stages.The direction of non-construction land conversion is slowly transitioning from urban to rural areas,with cultivated land mainly flowing to urban land,while rural residential areas are mostly in the direction of water area and forest land conversion.(3)The overall and various types of non-construction land conversion centers in urban and rural areas migrate to the east,showing a spatial pattern of "one ring,three lines and multiple points".The areas along the Shanghai-Suzhou-Wuxi corridor,the eastern part of Taihu Lake,and the southern bank of the Yangtze River are the hot spots for its conversion.The spatial characteristics of the town area are as follows: non-construction land conversion in the eastern town area is earlier than that in the western area,the conversion of cultivated land and water area is mostly discrete,and the conversion of forest land,grassland and unused land to the southwest is aggregated.(4)According to the detection of influence factors of different types of non-construction land conversion and overall conversion,socioeconomic factors are the main influencing factors to promote the overall conversion of non-construction land,cultivated land,water area,grassland and unused land.Among them,public services have the greatest explanatory power for non-construction land as a whole,cultivated land and water area conversion.The proportion of urban land and the population are the main influencing factors of grassland conversion and unused land conversion,respectively,while forest land conversion is mainly affected by natural environment factors.According to the interaction detection results,the two-factor interaction results are mostly nonlinear enhancement and two-factor enhancement.The interaction between socioeconomic factors and natural environment factors was generally less than the result of common interaction between them.The overall of non-construction land,cultivated land,water area and unused land conversion were strongly influenced by the interaction among socioeconomic factors,while forest land and grassland conversion were strongly influenced by the combined interaction of socioeconomic factors and natural environment factors.(5)In order to realize the sustainable utilization of urban and rural non-construction land in Suzhou,the overall level can be controlled from the following aspects:(1)Strict protection and use of development;(2)Promote the rehabilitation and restoration of cultivated land resources in a positive manner;(3)Build an ecological cyberspace system with blue-green interaction;(4)Promote and implement reverse planning.In terms of partition level:(1)Attention should be paid to strengthen government intervention in key urban control areas,effectively control construction land,and strictly control the delineation of urban growth boundaries;(2)For the northern plains along the Yangtze River,it is necessary to delineate the ecological control line along the Yangtze River,promote the development of high-efficiency agriculture on high-quality farmland,and build restoration demonstration areas on low-quality farmland;(3)In the Western Ecological control zone around Taihu Lake,the population can be guided to moderate concentration in towns to delineate forest land ecological protection boundaries;(4)As for the Southern Taihu water network plain control area,it is necessary to improve the connection network of rivers and lakes,establish an ecological compensation mechanism for cultivated land and water area,thus promoting the high-quality development of the region.