Differentiation And Correlation Of Spatial Pattern And Multifunction In Rural Settlements Considering Topographic Gradients

As the main gathering place of rural population,the pattern and function of rural settlements reflect the interaction between human activities and geographical environment.In recent years,with the rapid advancement of industrialization and urbanization,the scale and spatial distribution of rural settlements have been changing,and the urban-rural regional structure,rural industrial system,farmers’ life style and natural ecological environment have also undergone great changes.Based on this,the study of the geographical differentiation and pattern evolution of the scale,form,distribution and structure of rural settlements can reveal the footprints of human-land interaction in different regions and stages;and the study of the diversity,complexity and variability of the functions of rural settlements can effectively guide the reconstruction of the countryside and promote the coordinated and sustainable development of the region.This paper takes Tianshui City in Longzhong loess hill region as an example,based on the micro-geomorphic unit division to propose a new method of terrain gradient analysis applicable to mountain and hilly areas,from the grid scale,using the landscape pattern index and GIS spatial analysis methods to reveal the scale,morphology,distribution,structure of rural settlements of different characteristics;build rural settlements multi-functional evaluation system to measure the production,life,ecological functions of rural settlements The multi-functional evaluation system of rural settlements is constructed to measure the production,living and ecological functions of rural settlements,and analyze the intrinsic coordination relationship with the help of coupled coordination model;Spearman’s rank correlation analysis and bivariate spatial autocorrelation analysis are used to explore the trade-offs and synergy relationship between rural settlements "pattern-function" at both overall and local levels;on this basis,a comparative analysis of typical regional rural settlements is conducted,and corresponding optimization solutions are proposed.On the basis of this,a comparative analysis of typical regional rural settlements is conducted and corresponding optimization solutions are proposed.The main findings of the study are as follows.(1)Rural settlements in Tianshui City are mainly small in size,with serious fragmentation and a scattered distribution of "star-shaped" as a whole.From the statistical characteristics of the land scale of rural settlements in 9067 grids,the scale of rural settlements in Tianshui City is generally small,and the overall distribution is skewed.The overall complexity of the settlement form is relatively low,the distribution is relatively scattered,and the degree of spatial fragmentation is generally high.(2)The scale,morphology,distribution and structure of rural settlements in Tianshui City have obvious topographic gradient differentiation characteristics.As the topographic gradient rises,the distribution of TA,NP,AREA＿CV,MPI,PR,SHDI values are generally concentrated from high values to low values,the distribution of LFI values is generally dispersed from low values to high values,and the distribution of AWMSI and AWMPFD values is generally "arching bridge" type.In addition,the spatial distribution of TA,AWMSI,MPI and SHDI also has obvious high value clustering characteristics.(3)The overall level of living functions of rural settlements in Tianshui is low and the numerical variability is small,with concentrated and marginal distributions in geographic space and certain gradient differences;the overall level of production functions is low and the spatial distribution has a strong town orientation and obvious topographic gradient differences.The overall level of ecological functions is low,and the spatial distribution has obvious horizontal zonal differentiation patterns and topographic gradient differences.In addition,there is no good resonance among the three living functions,and the differences among the functions are large,showing an unbalanced development,and the overall is in a serious dysfunctional stage.(4)The scale,distribution and structure of rural settlements in Tianshui City are generally synergistic with production and living functions,while they are generally trade-off with ecological functions.In terms of spatial distribution,there is significant spatial heterogeneity in the trade-off-synergy relationship between rural settlement pattern and function.The spatial distribution of the trade-off-synergistic relationship between living function,production function and scale,distribution and structure is similar,while the trade-off-synergistic relationship between ecological function and scale,distribution and structure is opposite to both.(5)The four case areas with the same area,different gradients,and different topographic combinations under the same scale have completely different "patternfunction" characteristics.Taking into account the actual development of the region,this paper proposes four kinds of "pattern-function" optimization solutions for rural settlements,such as clustering and upgrading,optimization and adjustment,transformation and demolition,and feature-driven rural settlements.