Evaluation of Suitability and Spatial Distribution of Rural Settlements in the Karst Mountainous Area of China

Abstract

With the acceleration of urbanization and the implementation of the rural revitalization strategy, the spatial pattern of rural settlements in China has changed significantly. The suitability of rural settlements is a requirement for rural revitalization. The objective of this paper is to quantitatively depict, analyze, and evaluate the suitability of rural settlements in karst mountain areas to eliminate poverty and accelerate the process of new urbanization by constructing rural settlements. Taking 525 rural settlements in Songtao Miao Autonomous County, Guizhou Province, in the karst mountainous area as the research object, the distribution of rural settlements is studied using point mode spatial analysis and neighborhood analysis. The impacts of natural and regional environmental factors are detected using Geodetector. To make the evaluation results more scientific and reasonable, a suitability evaluation model based on Geodetector and AHP was constructed to solve the subjective problem of the weight assignment of the AHP method and reflect the interaction between the influencing factors. The results demonstrate the following. (1) The variation coefficient of the Thiessen polygon area in the Voronoi diagram shows that the spatial distribution of rural settlements is mainly random. The spatial distribution of kernel density in rural settlements presents multiple nuclear centers, with obvious spatial differentiation, with Changping Township being the densest and Waxi Township the sparsest. (2) Rural settlements are mainly distributed below a 15° slope, 800 m above sea level, within 6 km from rivers, 4 km from roads, and 7 km from the township center. Slope and distance from the river are the main driving forces of spatial differentiation. The spatial distribution of rural settlement areas is affected by natural and regional environmental factors, and the interaction between slope and distance from the river is the strongest explanatory power. (3) The results of suitability evaluation show that 87.40% of the rural settlement areas are categorized as “suitable” and “relatively suitable” for living. The “suitable” rural settlement areas are mainly concentrated in the hilly and low mountain areas and river valleys, with relatively gentle terrain in the middle and east, distributed in two north–south trending strips. The “relatively suitable” rural settlements are mainly scattered in the surrounding livable areas. This study could provide a reference for the planning and reconstruction of rural residential areas in karst mountain areas and expand the research means of suitability evaluation of rural residential areas, and it is applicable to other settings.