Objective The objective of this study was to take a typical county in the main grain-producing area of Northeast China as an example to explore and construct a basic research framework for the layout optimization of rural settlements. This was done to enhance the land-use efficiency of rural settlements, to safeguard food security, and to offer technical support for the formulation and adjustment of village layout plans.

Method Following the framework of “grading-classifying-determining the direction,” the Minimum Cumulative Resistance (MCR) model was employed to assess and grade the layout suitability of rural settlements in Faku County. The rural settlements were classified into different optimization types, and corresponding strategies were put forward. The weighted Voronoi diagram method was selected to identify the influence scope of central villages and determine the relocation directions of rural settlements.

Result Firstly, the areas suitable for the layout of rural settlements in Faku County were extensively distributed, covering 80% of the total area of the county. In these areas, it was essential to control the unregulated expansion of rural settlements. However, 16.5% of the rural settlements were located in unsuitable areas, and thus, it was urgent to optimize and relocate them. Secondly, among the rural settlements, the suburban-integrated type, which accounted for 26.5% of the total area, represented the potential space for urbanization. The key-development type, taking up 29.7%, was the main space for rural industrial development and the primary relocation direction for rural settlements. The controlled-development type had the largest proportion, reaching 33.1%, and its scale expansion should be strictly restricted. The merger-and-relocation type, accounting for 10.7%, should be relocated to the key-development type rural settlements while respecting the preferences of farmers. Thirdly, among the key-development type rural settlements, 118 central villages were identified as the optimal relocation destinations for rural settlements.

Conclusion In the black soil region of the main grain-producing area in Northeast China, cultivated land is widely distributed, and the layout suitability of rural settlements is relatively high. Therefore, optimizing the layout of rural settlements in this area is of great significance for China's food security. It can effectively improve the land-use efficiency of rural areas, which is conducive to the rational allocation of land resources. At the same time, a more scientific layout of rural settlements can also foster the development of rural industries and improve the living environment of rural residents, which will contribute to the overall development of rural areas and the stability of the national food supply.