Objective Rural settlements in mountainous areas encounter challenges that are typically more severe and complex than those in plain areas. The South Taihang Mountain area is an important ecological barrier in central China. It is of great significance to explore the spatial pattern characteristics of settlements in the South Taihang Mountain area and influencing factors thereof for the protection and development of settlements. Nonetheless, little attention has been paid to the macro-scale research on the spatial patterns of settlements in the South Taihang Mountain area. This research seeks to answer three key questions: What typical settlement types exist in this area? How are these settlements distributed? And what are the key factors influencing the formation of these settlement patterns in the South Taihang Mountain area?

Methods Upon extraction of settlement patches, relevant landscape indices and the minimum cumulative resistance (MCR) model are used to quantitatively study the spatial pattern of settlements in the South Taihang Mountain area in Xinxiang, with corresponding statistics being collected. The cluster analysis is carried out on the index data, and the basic types and distribution rules of settlements in the research area are summarized. On this basis, the geographically weighted regression (GWR) model is used to further explore the influencing factors of the spatial pattern characteristics of settlements in this area.

Results  1) The spatial pattern characteristics of settlements in the South Taihang Mountain area in Xinxiang have significant regional differences, and the spatial distribution of such settlements gradually changes with the terrain. Generally speaking, the settlements in the gentle zone have larger scale, higher density and more complex edge morphology, while the settlements in the deep mountain area have smaller scale, lower density and more regular edge morphology. The settlements in the research area are characterized by significant agglomeration and distribution. 2) According to the spatial pattern characteristics of settlements , the settlements in the research area can be divided into six categories in combination with topographic conditions. The number of strip settlements with small scale and medium density is the largest across the area, which is the most common type in mountain settlements; the two types of settlements with large scale, high density and complex shape take the second place, mostly distributed in piedmont plains, hilly areas and basins. 3) Precipitation and temperature are the most critical factors restricting the settlement scale in the South Taihang Mountain area; elevation, population size, slope, accessibility, distance to water system, distance to cultivated land, and cultivated land area also have a certain impact on the settlement scale; slope direction, settlement patch distance and geological disaster loss have little effect on the area of mountainous towns, and there exists obvious spatial heterogeneity. In general, the impact of various factors on settlement scale is typically small in mountainous areas, while more obvious in areas with lower altitude, with precipitation being an exception, which has little impact in plain areas and great impact in mountainous areas. Most of the other influencing factors of landscape pattern index that reflect the characteristics of settlement shape and proximity have unsatisfactory regression results, and the explanatory power of model is weak. 4) At present, the spatial pattern characteristics of settlements in the South Taihang Mountain area are not the result of a single factor, but are determined by the superposition of multiple factors. The terrain determines the hydrothermal conditions. The interactive terrain conditions, land resources, precipitation and other natural environmental factors, as well as the historical and cultural factors such as immigrants from Shanxi, Baixing ancient road, and Baiquan pharmaceutical trading market, jointly shape the overall pattern of the spatial distribution of settlements in the South Taihang Mountain area in Xinxiang.

Conclusion  On the basis of geographical grid, the research breaks the boundaries of traditional administrative divisions, accurately describes the three attribute characteristics of the spatial pattern of settlements in the South Taihang Mountain area based on the geographical grid scale, defines the settlement types in the area, and uses the geographically weighted regression model to analyze the influence degree of each factor in different geographical locations, revealing their specific impact on the spatial pattern of settlements. The spatial pattern of settlements is the basis for the classification and improvement of rural settlements. In order to effectively promote the rural revitalization strategy in the South Taihang Mountain area, it is supposed to focus on the spatial distribution characteristics of rural settlements and the influencing factors behind them, and pay attention to the geographical conditions and cultural background of villages, so as to formulate appropriate and reasonable layout planning according to the actual situation of different regions. When promoting the optimization of rural settlement space, traditional villages should be protected, and factors such as natural environment, social economy and accessibility should be considered. The planning needs to take targeted optimization measures according to the characteristics of different settlements, such as enhancing transportation infrastructure, integrating scattered settlements, and implementing relocation strategies. At the same time, it is necessary to reasonably plan the land for rural settlements, protect the ecological environment, define the production and living spaces, build rural tourism and leisure areas based on the resource advantages of the South Taihang Mountain area, and promote the construction of beautiful villages and tourism development. For settlement lands beyond the environmental carrying capacity, the strategy of orderly vacation should be implemented to ensure sustainable development.