Spatio-temporal Evolution And Spatial Restructuring Of Rural Settlements In Mountainous Regions Under The Background Of Rapid Urbanization

Since the reform and opening up,and along with the rapid propelling of urbanization,the mountainous settlements,which are the main carriers of mountainous area residents’ residences and conducting social and economic activities such as production and living,have undergone drastic changes,their numbers,scales,spatial patterns,and spatial structures have undergone significant changes.At the same time,the development of rural settlements which are a basis for administrative divisions and management units(or basic self-government units)in the mountainous areas directly affects the overall situation of accurate poverty alleviation in China and the construction of an overall well-to-do society.It is the success or failure touchstone of building a harmonious socialist society.And it is also a difficult point in the construction of a new socialist countryside and the difficulty in implementing the current strategy for rural revitalization.Therefore,we should understand the temporal and spatial patterns of rural settlements in the mountainous area,grasp the mechanism of the spatial evolution of rural settlements in mountainous areas,grasp the future development direction of rural settlements in the mountainous areas,which will enrich the research content of settlements,and promote the implementation of the mountainous areas poverty alleviation strategy and the rural village rejuvenation strategy,as well as the long-term sustained and good development of the settlements in the mountain area.This has important theoretical and practical significance.This study is conducted under this backround.Taking the most populous and relatively representative county of Songxian in the key mountainous counties of the national poverty alleviation and development work in the concentrated mountainous areas of western Henan as a research case.Based on geography and economics related theories,such as man-land relations theory,location theory,spatial structure theory,path dependence theory,space production theory,life quality theory and public product theory,et al.Taking spatial pattern——evolutionary process——evolutionary mechanism——spatial optimization and reconstruction of county settlements in the mountainous areas as the main line.Using natural fracture point classification and linear regression analysis methods,analyzed the spatial-temporal changes of the relationship between settlement patches and population from the scales of the whole township,different elevations,different subdivisions,and different townships between each divisions in the seven townships;Utilizing the spatial analysis method combines index methods such as topographic relief,topographic index,and fractal dimension,to analyzes the spatial distribution characteristics and evolution of the settlements in general and subarea,as well as the spatial structure evolution of the settlements and the evolution of the settlements central place hierarchy system.Applying the factor analysis and the geo-detector model,multivariate regression analysis methods,spatial econometric models(including spatial lag model SLM,spatial error model SEM,and geographically weighted regression model GWR),analyzed the spatio-temporal changes of the factors affecting the spatial distribution of the Songxian settlements from natural villages,administrative villages and townships;Based on space production theory,life quality theory,niche theory and residential field theory,according to the principle of proximity,using weighted voronoi map and contrasting the size of the “living field” between the settlements,realized the combination of macro and micro perspectives,to obtain the reconstructed direction of the settlement of Songxian county.The study has the following findings:Firstly,in the four periods of 1975,1995,2008 and 2015,the whole relationship between settlement patches and population has a strong correlation.And the correlation between the area of patches and population at different elevations shows that hilly area> low mountain area> mid-mountainous area(except 1975);but with time,the relationship in mid-mountainous area presentation gradually decreases,other hills and low mountains show fluctuations change.The relationship in different subdistricts are both relatively high.Among them,in hilly shallow mountain area and shallow mountain area,the relationship in town is higher than that of the village,while in the shallow deep mountain area the relationship of Checun town is the highest.The study also concludes that the use of settlement patch data instead of population data to analyze the spatial evolution of settlements at or above the county level is still feasible,and some regular problems can be found.But at or under the township level the population data or combining demographic data with settlement patch data for analysis will be more accurate and reliable,and it will have more practical significance.Secondly,the temporal and spatial characteristics of settlement evolution:(1)The number of settlements decreased nearly a quarter while their scale increased more than 1.2 times over the past 40 years,however,the number during the period from 1975 to 1995 reduced more than that of time from 1995 to 2015,while the scale expansion was more significant during the period from 1995 to 2015.(2)Restricted by mountain topography the settlements mainly distributed along the main roads and rivers presenting like ribbons,as well as distributed along the county site and township sites forming massive texture,and their evolution followed strong path dependence;(3)The spatial distribution of settlements tended to locate obviously low land,smaller topography,gentle slope and small relief,or more settlements concentrated in the hilly region,flat and slightly undulating topography,and the areas where the slope degree is less than 6 ° and the terrain niche index that is less than 0.4;In addition,the south slope directivity of settlements’ location and the the south slope,southeast slope and southwest slope directivity of settlement scale’s spatial distribution was gradually strengthened.(4)The spatial distribution of the whole county’s settlements was dendritic or line-network structures and did not change significantly with time,but they changed in local areas.Among them,the line-network structure that appeared partially in 1975 developed into a band-network structure.The block structure develops into a band-like or planar structure,and the band-like structure expands.Scatter-like structures have been reduced or developed into massive structures;and the county has formed a dual-core structure which taking the county as the center and the township as the sub-center.(5)In different periods,the quantitative relationship structure of the center of the settlements in Songxian county basically presented the “pyramid” model,but the quantitative relationship between the spatial structure of the central hierarchy and the hierarchical system of the central location in various periods did not conform to the market,traffic,and administrative principles of the central theory of Christale,but in accordance with the distribution of the law under the combination of several principles,and in different periods this distribution law is different.At the beginning,the river and the terrain played an important role,and later,the terrain and transport played determine roles,then the role of the market is more and more significant,and the principle of separation has been working;the spatial structure of the settlement center mainly presents a mixture of shapes such as linear,triangular,quadrilateral,and other irregular polygons,and the space structure changes from time to time and tends to be complex.Thirdly,the influencing factors and their changes of the spatial distribution of settlements:(1)The location of settlements is mainly affected by the terrain,production conditions,and the radiation of roads,township centers,county centers,and industrial and mining enterprises.However,over time,the influence of terrain is weakening,and the radiation effects of roads and township centers are increasing,among them,The rivers’ impact was only positive in 1975.It was weakened and then strengthened by the negative influence of the distance to the road;the positive influence from the near distance of the township center gradually weakened,and the positive influence from the distance from the center of the county town was strengthened first and weakened later.The positive influence of land production conditions weakened gradually from 1995 to 2015;the radiation impact of industrial and mining enterprises was significant only in 1995 and 2015 but the previous period was negative and the latter was positive.The positive effects of pigs and large livestock have gradually weakened and the positive effects of goat farming have gradually increased.In addition,there are spatial differences in the influence of the terrain,river distance,road distance,distance between town and town center distances,the distance between the center of the county center,the number of labor force,the production conditions,and the proximity of the industrial and mining enterprises.Changes over time and varys from place to place.(2)The spatial distribution of settlement scales is significantly influenced by natural,social,and economic factors,and changes over time.Among them,the influence of topography is relatively large,and the impact of township and county centers in social and economic factors is secondary.With the accelerating process of urbanization,the impact of the county center has gradually increased,while the impact of township centers and terrain has gradually weakened.Among them,the impact of topographic factors and production conditions were only negatively affected in 1995 and 2015,but the former gradually increased while the latter gradually weakened.Affected by rivers only had a significant negative impact during the 1975 period.The positive influence of the labor force increases first and then weakens.In addition,the spatial distribution of the settlements in Songxian county in 1975 and 1995 was influenced by the spatial distance of rivers,roads,the distances of township centers,the distances of county towns centers,industrial and mining enterprises,and family farming.And they have spatial difference which changes over time.But in 2015,the spatial differences affected by the terrain,the number of laborers,and the production conditions are small and can be largely ignored.Fourthly,the reconstruction direction of the settlements in Songxian county can be divided into four categories: urbanization type,key development type,control expansion type,and migration consolidation type:(1)In the process of optimization and reconstruction of urbanization-type rural settlement space,the village planning of rural settlements should be included in the urban planning system,the community type suitable for the peasants is designed,and the residents are guided to focus on the residential quarters.(2)During the process of optimizing and reconstructing of the key development-type settlement space,this type of settlement should be regarded as a central settlement(residential site),focusing on concentrate modernized settlements,and a small,scattered and small-scale rural settlement center should be guided to the center.(3)In the process of optimizing and reconstructing rural settlements for control expansion,the overall layout of villages shall be adopted.Based on the village’s overall planning,relying on the unique advantages of each village and improving the layout,the villagers shall pay attention to the idle land behind the homestead of the villagers’ houses.Increase the renovation of Hollow Village and one-family multi-use land,and at the same time,strictly control the extension of new village construction,and effectively improve the village’s level of intensive land use.In addition,we should also improve the infrastructure construction of this type of settlements with the outside world,strengthen the connection with market town or village center.(4)For the settlements that need to relocate merged,the relocation should be followed by the principle of “relocating from a low residential area to a high-residual-holding area,and facilitating the integration of displaced farmers and displaced farmers”.Adopt the method of whole of local relocation but centralized resettlement,and reasonably arrange the relocation of residents’ houses,arrange the production and living of the immigrants,increase the efficiency of land use,and build and share the infrastructure.